Sample records for a1 iga1 cleaved

  1. Lack of cleavage of immunoglobulin A (IgA) from rhesus monkeys by bacterial IgA1 proteases.

    PubMed Central

    Reinholdt, J; Kilian, M

    1991-01-01

    Bacterial immunoglobulin A1 (IgA1) proteases cleaving IgA1 and secretory IgA1 molecules in the hinge region are believed to be important virulence factors. Previous studies have indicated that IgA of humans, gorillas, and chimpanzees are the exclusive substrates of these enzymes. In a recent study, IgA from the rhesus monkey was found to be susceptible to the IgA1 protease activity of Streptococcus pneumoniae. In an attempt to reproduce this observation, we found that neither five isolates of S. pneumoniae nor other IgA1 protease-producing bacteria representing different cleavage specificities caused cleavage of rhesus monkey IgA. Hence, the rhesus monkey does not appear to be a suitable animal model for studies of IgA1 proteases as virulence factors. Images PMID:2037384

  2. Immunoglobulins in Nasal Secretions of Healthy Humans: Structural Integrity of Secretory Immunoglobulin A1 (IgA1) and Occurrence of Neutralizing Antibodies to IgA1 Proteases of Nasal Bacteria

    PubMed Central

    Kirkeby, Line; Rasmussen, Trine Tang; Reinholdt, Jesper; Kilian, Mogens

    2000-01-01

    Certain bacteria, including overt pathogens as well as commensals, produce immunoglobulin A1 (IgA1) proteases. By cleaving IgA1, including secretory IgA1, in the hinge region, these enzymes may interfere with the barrier functions of mucosal IgA antibodies, as indicated by experiments in vitro. Previous studies have suggested that cleavage of IgA1 in nasal secretions may be associated with the development and perpetuation of atopic disease. To clarify the potential effect of IgA1 protease-producing bacteria in the nasal cavity, we have analyzed immunoglobulin isotypes in nasal secretions of 11 healthy humans, with a focus on IgA, and at the same time have characterized and quantified IgA1 protease-producing bacteria in the nasal flora of the subjects. Samples in the form of nasal wash were collected by using a washing liquid that contained lithium as an internal reference. Dilution factors and, subsequently, concentrations in undiluted secretions could thereby be calculated. IgA, mainly in the secretory form, was found by enzyme-linked immunosorbent assay to be the dominant isotype in all subjects, and the vast majority of IgA (median, 91%) was of the A1 subclass, corroborating results of previous analyses at the level of immunoglobulin-producing cells. Levels of serum-type immunoglobulins were low, except for four subjects in whom levels of IgG corresponded to 20 to 66% of total IgA. Cumulative levels of IgA, IgG, and IgM in undiluted secretions ranged from 260 to 2,494 (median, 777) μg ml−1. IgA1 protease-producing bacteria (Haemophilus influenzae, Streptococcus pneumoniae, or Streptococcus mitis biovar 1) were isolated from the nasal cavities of seven subjects at 2.1 × 103 to 7.2 × 106 CFU per ml of undiluted secretion, corresponding to 0.2 to 99.6% of the flora. Nevertheless, α-chain fragments characteristic of IgA1 protease activity were not detected in secretions from any subject by immunoblotting. Neutralizing antibodies to IgA1 proteases of autologous

  3. A comparison of the binding of secretory component to immunoglobulin A (IgA) in human colostral S-IgA1 and S-IgA2

    PubMed Central

    Almogren, Adel; Senior, Bernard W; Kerr, Michael A

    2007-01-01

    A detailed investigation of the binding of secretory component to immunoglobulin A (IgA) in human secretory IgA2 (S-IgA2) was made possible by the development of a new method of purifying S-IgA1, S-IgA2 and free secretory component from human colostrum using thiophilic gel chromatography and chromatography on Jacalin-agarose. Sodium dodecyl sulphate–polyacrylamide gel electrophoresis of unreduced pure S-IgA2 revealed that, unlike in S-IgA1, a significant proportion of the secretory component was bound non-covalently in S-IgA2. When S-IgA1 was incubated with a protease purified from Proteus mirabilis the secretory component, but not the α-chain, was cleaved. This is in contrast to serum IgA1, in which the α-chain was cleaved under the same conditions – direct evidence that secretory component does protect the α-chain from proteolytic cleavage in S-IgA. Comparisons between the products of cleavage with P. mirabilis protease of free secretory component and bound secretory component in S-IgA1 and S-IgA2 also indicated that, contrary to the general assumption, the binding of secretory component to IgA is different in S-IgA2 from that in S-IgA1. PMID:17156102

  4. β1,4-galactosyltransferase 1 is a novel receptor for IgA in human mesangial cells.

    PubMed

    Molyneux, Karen; Wimbury, David; Pawluczyk, Izabella; Muto, Masahiro; Bhachu, Jasraj; Mertens, Peter R; Feehally, John; Barratt, Jonathan

    2017-12-01

    IgA nephropathy is characterized by mesangial deposition of IgA, mesangial cell proliferation, and extracellular matrix production. Mesangial cells bind IgA, but the identity of all potential receptors involved remains incomplete. The transferrin receptor (CD71) acts as a mesangial cell IgA receptor and its expression is upregulated in many forms of glomerulonephritis, including IgA nephropathy. CD71 is not expressed in healthy glomeruli and blocking CD71 does not completely abrogate mesangial cell IgA binding. Previously we showed that mesangial cells express a receptor that binds the Fc portion of IgA and now report that this receptor is an isoform of β-1,4-galactosyltransferase. A human mesangial cell cDNA library was screened for IgA binding proteins and β-1,4-galactosyltransferase identified. Cell surface expression of the long isoform of β-1,4-galactosyltransferase was shown by flow cytometry and confocal microscopy and confirmed by immunoblotting. Glomerular β-1,4-galactosyltransferase expression was increased in IgA nephropathy. IgA binding and IgA-induced mesangial cell phosphorylation of spleen tyrosine kinase and IL-6 synthesis were inhibited by a panel of β-1,4-galactosyltransferase-specific antibodies, suggesting IgA binds to the catalytic domain of β-1,4-galactosyltransferase. Thus, β-1,4-galactosyltransferase is a constitutively expressed mesangial cell IgA receptor with an important role in both mesangial IgA clearance and the initial response to IgA deposition. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  5. Galactosylation of IgA1 Is Associated with Common Variation in C1GALT1.

    PubMed

    Gale, Daniel P; Molyneux, Karen; Wimbury, David; Higgins, Patricia; Levine, Adam P; Caplin, Ben; Ferlin, Anna; Yin, Peiran; Nelson, Christopher P; Stanescu, Horia; Samani, Nilesh J; Kleta, Robert; Yu, Xueqing; Barratt, Jonathan

    2017-07-01

    IgA nephropathy (IgAN), an important cause of kidney failure, is characterized by glomerular IgA deposition and is associated with changes in O -glycosylation of the IgA1 molecule. Here, we sought to identify genetic factors contributing to levels of galactose-deficient IgA1 (Gd-IgA1) in white and Chinese populations. Gd-IgA1 levels were elevated in IgAN patients compared with ethnically matched healthy subjects and correlated with evidence of disease progression. White patients with IgAN exhibited significantly higher Gd-IgA1 levels than did Chinese patients. Among individuals without IgAN, Gd-IgA1 levels did not correlate with kidney function. Gd-IgA1 level heritability (h 2 ), estimated by comparing midparental and offspring Gd-IgA1 levels, was 0.39. Genome-wide association analysis by linear regression identified alleles at a single locus spanning the C1GALT1 gene that strongly associated with Gd-IgA1 level ( β =0.26; P =2.35×10 -9 ). This association was replicated in a genome-wide association study of separate cohorts comprising 308 patients with membranous GN from the UK ( P <1.00×10 -6 ) and 622 controls with normal kidney function from the UK ( P <1.00×10 -10 ), and in a candidate gene study of 704 Chinese patients with IgAN ( P <1.00×10 -5 ). The same extended haplotype associated with elevated Gd-IgA1 levels in all cohorts studied. C1GALT1 encodes a galactosyltransferase enzyme that is important in O -galactosylation of glycoproteins. These findings demonstrate that common variation at C1GALT1 influences Gd-IgA1 level in the population, which independently associates with risk of progressive IgAN, and that the pathogenic importance of changes in IgA1 O -glycosylation may vary between white and Chinese patients with IgAN. Copyright © 2017 by the American Society of Nephrology.

  6. RNA-cleaving properties of human apurinic/apyrimidinic endonuclease 1 (APE1)

    PubMed Central

    Kim, Wan-Cheol; King, Dustin; Lee, Chow H.

    2010-01-01

    We have recently identified apurinic/apyrimidinic endonuclease 1 (APE1) as an endoribonuclease that cleaves c-myc mRNA in vitro and regulates c-myc mRNA levels and half-life in cells. This study was undertaken to further unravel the RNA-cleaving properties of APE1. Here, we show that APE1 cleaves RNA in the absence of divalent metal ions and, at 2 mM, Zn2+, Ni2+, Cu2+, or Co2+ inhibited the endoribonuclease activity of APE1. APE1 is able to cleave CD44 mRNA, microRNAs (miR-21, miR-10b), and three RNA components of SARS-corona virus (orf1b, orf3, spike) suggesting that, when challenged, it can cleave any RNAs in vitro. APE1 does not cleave strong doublestranded regions of RNA and it has a strong preference for 3’ of pyrimidine, especially towards UA, CA, and UG sites at single-stranded or weakly paired regions. It also cleaves RNA weakly at UC, CU, AC, and AU sites in single-stranded or weakly paired regions. Finally, we found that APE1 can reduce the ability of the Dicer enzyme to process premiRNAs in vitro. Overall, this study has revealed some previously unknown biochemical properties of APE1 which has implications for its role in vivo. PMID:21968700

  7. Serum under-O-glycosylated IgA1 level is not correlated with glomerular IgA deposition based upon heterogeneity in the composition of immune complexes in IgA nephropathy.

    PubMed

    Satake, Kenji; Shimizu, Yoshio; Sasaki, Yohei; Yanagawa, Hiroyuki; Suzuki, Hitoshi; Suzuki, Yusuke; Horikoshi, Satoshi; Honda, Shinichiro; Shibuya, Kazuko; Shibuya, Akira; Tomino, Yasuhiko

    2014-06-13

    Although serum under-O-glycosylated IgA1 in IgA nephropathy (IgAN) patients may deposit more preferentially in glomeruli than heavily-O-glycosylated IgA1, the relationship between the glomerular IgA deposition level and the O-glycan profiles of serum IgA1 remains obscure. Serum total under-O-glycosylated IgA1 levels were quantified in 32 IgAN patients by an enzyme-linked immunosorbent assay (ELISA) with Helix aspersa (HAA) lectin. Serum under-O-glycosylated polymeric IgA1 (pIgA1) was selectively measured by an original method using mouse Fcα/μ receptor (mFcα/μR) transfectant and flow cytometry (pIgA1 trap). The percentage area of IgA deposition in the whole glomeruli (Area-IgA) was quantified by image analysis on the immunofluorescence of biopsy specimens. Correlations were assessed between the Area-IgA and data from HAA-ELISA or pIgA1 trap. The relationships between clinical parameters and data from HAA-ELISA or pIgA1 trap were analyzed by data mining approach. While the under-O-glycosylated IgA1 levels in IgAN patients were significantly higher than those in healthy controls when measured (p<0.05), there was no significant difference in under-O-glycosylated pIgA1. There was neither a correlation observed between the data from HAA-ELISA and pIgA1 trap (r2=0.09) in the IgAN patients (r2=0.005) nor was there a linear correlation between Area-IgA and data from HAA-ELISA or the pIgA1 trap (r2=0.005, 0.03, respectively). Contour plots of clinical parameters versus data from HAA-ELISA and the pIgA1 trap revealed that patients with a high score in each clinical parameter concentrated in specific areas, showing that patients with specific O-glycan profiles of IgA1 have similar clinical parameters. A decision tree analysis suggested that dominant immune complexes in glomeruli were consisted of: 1) IgA1-IgG and complements, 2) pIgA1 and complements, and 3) monomeric IgA1-IgA or aggregated monomeric IgA1. Serum under-O-glycosylated IgA1 levels are not correlated with

  8. Naturally Occurring Structural Isomers in Serum IgA1 O-Glycosylation

    PubMed Central

    Takahashi, Kazuo; Smith, Archer D.; Poulsen, Knud; Kilian, Mogens; Julian, Bruce A.; Mestecky, Jiri; Novak, Jan; Renfrow, Matthew B.

    2013-01-01

    IgA is the most abundantly produced antibody and plays an important role in the mucosal immune system. Human IgA is represented by two isotypes, IgA1 and IgA2. The major structural difference between these two subclasses is the presence of nine potential sites of O-glycosylation in the hinge region between the first and second constant region domains of the heavy chain. Thr225, Thr228, Ser230, Ser232 and Thr236 have been identified as the predominant sites of O-glycan attachment. The range and distribution of O-glycan chains at each site within the context of adjacent sites in this clustered region create a complex heterogeneity of surface epitopes that is incompletely defined. We previously described the analysis of IgA1 O-glycan heterogeneity by use of high resolution LC/MS and electron capture dissociation tandem MS to unambiguously localize all amino acid attachment sites in IgA1 (Ale) myeloma protein. Here, we report the identification and elucidation of IgA1 O-glycopeptide structural isomers that occur based on amino acid position of the attached glycans (positional isomers) and the structure of the O-glycan chains at individual sites (glycan isomers). These isomers are present in a model IgA1 (Mce1) myeloma protein and occur naturally in normal human serum IgA1. Variable O-glycan chains attached to Ser230, Thr233 or Thr236 produce the predominant positional isomers, including O-glycans composed of a single GalNAc residue. These findings represent the first definitive identification of structural isomeric IgA1 O-glycoforms, define the single-site heterogeneity for all O-glycan sites in a single sample, and have implications for defining epitopes based on clustered O-glycan variability. PMID:22067045

  9. HIV-1-Specific IgA Monoclonal Antibodies from an HIV-1 Vaccinee Mediate Galactosylceramide Blocking and Phagocytosis

    PubMed Central

    2018-01-01

    ABSTRACT Vaccine-elicited humoral immune responses comprise an array of antibody forms and specificities, with only a fraction contributing to protective host immunity. Elucidation of antibody effector functions responsible for protective immunity against human immunodeficiency virus type 1 (HIV-1) acquisition is a major goal for the HIV-1 vaccine field. Immunoglobulin A (IgA) is an important part of the host defense against pathogens; however, little is known about the role of vaccine-elicited IgA and its capacity to mediate antiviral functions. To identify the antiviral functions of HIV-1-specific IgA elicited by vaccination, we cloned HIV-1 envelope-specific IgA monoclonal antibodies (MAbs) by memory B cell cultures from peripheral blood mononuclear cells from an RV144 vaccinee and produced two IgA clonal cell lines (HG129 and HG130) producing native, nonrecombinant IgA MAbs. The HG129 and HG130 MAbs mediated phagocytosis by monocytes, and HG129 blocked HIV-1 Env glycoprotein binding to galactosylceramide, an alternative HIV-1 receptor. These findings elucidate potential antiviral functions of vaccine-elicited HIV-1 envelope-specific IgA that may act to block HIV-1 acquisition at the portal of entry by preventing HIV-1 binding to galactosylceramide and mediating antibody Fc receptor-mediated virion phagocytosis. Furthermore, these findings highlight the complex and diverse interactions of vaccine-elicited IgA with pathogens that depend on IgA fine specificity and form (e.g., multimeric or monomeric) in the systemic circulation and mucosal compartments. IMPORTANCE Host-pathogen interactions in vivo involve numerous immune mechanisms that can lead to pathogen clearance. Understanding the nature of antiviral immune mechanisms can inform the design of efficacious HIV-1 vaccine strategies. Evidence suggests that both neutralizing and nonneutralizing antibodies can mediate some protection against HIV in animal models. Although numerous studies have characterized the

  10. Cloning and structural analysis of two highly divergent IgA isotypes, IgA1 and IgA2 from the duck billed platypus, Ornithorhynchus anatinus.

    PubMed

    Vernersson, M; Belov, K; Aveskogh, M; Hellman, L

    2010-01-01

    To trace the emergence of modern IgA isotypes during vertebrate evolution we have studied the immunoglobulin repertoire of a model monotreme, the platypus. Two highly divergent IgA-like isotypes (IgA1 and IgA2) were identified and their primary structures were determined from full-length cDNAs. A comparative analysis of the amino acid sequences for IgA from various animal species showed that the two platypus IgA isotypes form a branch clearly separated from their eutherian (placental) counterparts. However, they still conform to the general structure of eutherian IgA, with a hinge region and three constant domains. This indicates that the deletion of the second domain and the formation of a hinge region in IgA did occur very early during mammalian evolution, more than 166 million years ago. The two IgA isotypes in platypus differ in primary structure and appear to have arisen from a very early gene duplication, possibly preceding the metatherian eutherian split. Interestingly, one of these isotypes, IgA1, appears to be expressed in only the platypus, but is present in the echidna based on Southern blot analysis. The platypus may require a more effective mucosal immunity, with two highly divergent IgA forms, than the terrestrial echidna, due to its lifestyle, where it is exposed to pathogens both on land and in the water. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. Novel lectin-independent approach to detect galactose-deficient IgA1 in IgA nephropathy.

    PubMed

    Yasutake, Junichi; Suzuki, Yusuke; Suzuki, Hitoshi; Hiura, Naoko; Yanagawa, Hiroyuki; Makita, Yuko; Kaneko, Etsuji; Tomino, Yasuhiko

    2015-08-01

    Galactose-deficient IgA1 (Gd-IgA1) is a critical effector molecule in the pathogenesis of IgA nephropathy (IgAN). Although many researchers have measured serum levels of Gd-IgA1 using snail helix aspersa agglutinin (HAA) lectin-based assay, the lectin-dependent assay has some serious problems in robustness. In this study, we aimed to establish a more robust and stable enzyme-linked immunosorbent assay (ELISA) method that uses a specific monoclonal antibody to recognize a hinge region in human Gd-IgA1 (Gd-IgA1 ELISA). Rats were immunized with human Gd-IgA1 hinge region peptide to obtain Gd-IgA1-specific monoclonal antibody KM55. Gd-IgA1 ELISA for specifically detecting serum Gd-IgA1 was consequently constructed. Serum Gd-IgA1 concentrations in human subjects were measured using KM55 ELISA assay. To further confirm specificity of the Gd-IgA1-specific antibody, KM55 was also applied for immunofluorescence staining of glomerular Gd-IgA1 in paraffin-embedded sections of renal biopsy specimens. Measurement of serum levels of Gd-IgA1 in human subjects by Gd-IgA1 ELISA revealed increased serum Gd-IgA1 level in patients with IgAN compared with patients with other renal diseases or non-renal diseases. Importantly, the results obtained from Gd-IgA1 ELISA positively correlated with those from the HAA lectin-based assay (R = 0.75). Immunofluorescence staining of renal biopsy specimens with KM55 detected glomerular co-localization of Gd-IgA1 and IgA. This novel lectin-independent method with KM55 for measuring serum levels of Gd-IgA1 can pave the way for more convincing diagnosis and activity assessment of IgAN, and can expedite clinical research to better understand this difficult disease. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA.

  12. Novel lectin-independent approach to detect galactose-deficient IgA1 in IgA nephropathy

    PubMed Central

    Yasutake, Junichi; Suzuki, Yusuke; Suzuki, Hitoshi; Hiura, Naoko; Yanagawa, Hiroyuki; Makita, Yuko; Kaneko, Etsuji; Tomino, Yasuhiko

    2015-01-01

    Background Galactose-deficient IgA1 (Gd-IgA1) is a critical effector molecule in the pathogenesis of IgA nephropathy (IgAN). Although many researchers have measured serum levels of Gd-IgA1 using snail helix aspersa agglutinin (HAA) lectin-based assay, the lectin-dependent assay has some serious problems in robustness. In this study, we aimed to establish a more robust and stable enzyme-linked immunosorbent assay (ELISA) method that uses a specific monoclonal antibody to recognize a hinge region in human Gd-IgA1 (Gd-IgA1 ELISA). Methods Rats were immunized with human Gd-IgA1 hinge region peptide to obtain Gd-IgA1-specific monoclonal antibody KM55. Gd-IgA1 ELISA for specifically detecting serum Gd-IgA1 was consequently constructed. Serum Gd-IgA1 concentrations in human subjects were measured using KM55 ELISA assay. To further confirm specificity of the Gd-IgA1-specific antibody, KM55 was also applied for immunofluorescence staining of glomerular Gd-IgA1 in paraffin-embedded sections of renal biopsy specimens. Results Measurement of serum levels of Gd-IgA1 in human subjects by Gd-IgA1 ELISA revealed increased serum Gd-IgA1 level in patients with IgAN compared with patients with other renal diseases or non-renal diseases. Importantly, the results obtained from Gd-IgA1 ELISA positively correlated with those from the HAA lectin-based assay (R = 0.75). Immunofluorescence staining of renal biopsy specimens with KM55 detected glomerular co-localization of Gd-IgA1 and IgA. Conclusion This novel lectin-independent method with KM55 for measuring serum levels of Gd-IgA1 can pave the way for more convincing diagnosis and activity assessment of IgAN, and can expedite clinical research to better understand this difficult disease. PMID:26109484

  13. Serological Analysis of Immunogenic Properties of Recombinant Meningococcus IgA1 Protease-Based Proteins.

    PubMed

    Kotelnikova, O V; Zinchenko, A A; Vikhrov, A A; Alliluev, A P; Serova, O V; Gordeeva, E A; Zhigis, L S; Zueva, V S; Razgulyaeva, O A; Melikhova, T D; Nokel, E A; Drozhzhina, E Yu; Rumsh, L D

    2016-07-01

    Using the genome sequence of IgA1 protease of N. meningitidis of serogroup B, four recombinant proteins of different structure and molecular weight were constructed. These proteins were equal in inducing the formation of specific antibodies to IgA1 protease and had protective properties against meningococci. In the sera of immunized mice, anti-IgA1 protease antibodies were detected by whole-cell ELISA, which indicated the presence of IgA1 protease on the surface of these bacteria. We hypothesized that the protective properties of IgA1 protease-based antigens and IgA1 protease analogs could be realized not only via impairment of bacterium adhesion to the mucosa, but also via suppression of this pathogen in the organism. The presented findings seem promising for using these proteins as the basis for anti-meningococcus vaccine.

  14. Impaired selection of IgA and intestinal dysbiosis associated with PD-1-deficiency

    PubMed Central

    Maruya, Mikako; Kawamoto, Shimpei; Kato, Lucia M.; Fagarasan, Sidonia

    2013-01-01

    A major function of immunoglobulin A (IgA) is to maintain balanced bacterial communities in the gut. We have previously shown that diversification of IgA upon somatic hypermutation (SHM) is critical for IgA function yet the principles governing the selection of IgA in the gut have remained elusive. Here we discuss recent progress in understanding this process as revealed by our studies in mice that lack the inhibitory co-receptor programmed cell death–1 (PD-1). We found that PD-1 affects the dynamics of germinal center (GC) B cells by controlling the number and the nature of T helper cells in the Peyer’s patches (PPs). Deregulation of the T cell compartment impacts the selection of IgA plasma cells leading to gut dysbiosis. When the PD-1-dependent checkpoint is missing, gut bacteria go beyond the mucosal barrier and induce systemic GCs that can generate antibodies with auto-reactive properties. PMID:23333864

  15. In vivo cleavage of immunoglobulin A1 by immunoglobulin A1 proteases from Prevotella and Capnocytophaga species.

    PubMed

    Frandsen, E V; Reinholdt, J; Kjeldsen, M; Kilian, M

    1995-10-01

    Immunoglobulin A1 (IgA1) proteases secreted by oral Prevotella and Capnocytophaga species specifically cleave IgA1 at the same peptide bond in the hinge region, leaving intact monomeric Fab and Fc fragments. Assuming that Prevotella- and Capnocytophaga-induced Fab fragments of IgA1 expose a specific immunogenic neoepitope at the cleavage site, we established an enzyme-linked immunosorbent assay to measure human serum antibodies to this neoepitope as indirect evidence of in vivo activity of Prevotella and Capnocytophaga IgA1 proteases. The assay used a monoclonal antibody with specificity for the neoepitope, and the ability to block binding of the monoclonal antibody to the neoepitope was investigated. Absorption of sera with Prevotella melaninogenica-induced Fab fragments of IgA1 resulted in removal of antibodies blocking binding of the monoclonal antibody, whereas absorption with Fab fragments induced by bacterial IgA1 proteases of other cleavage specificities did not remove blocking antibodies. Consequently, we assume that the antibodies detected had been induced by a neoepitope an the Fab fragment of IgA1 exposed exclusively after cleavage with IgA1 proteases from Prevotella and Capnocytophaga, indicating in vivo activity of these IgA1 proteases. Evidence, though indirect, of in vivo activity of Prevotella and Capnocytophaga IgA1 proteases was present in 42 of 92 sera examined and in a significantly higher proportion of sera from adults with periodontal disease compared with control individuals. No correlation with disease was observed for the juvenile periodontitis groups.

  16. [Isolation and characteristics of IgA1 and its use for detecting bacterial IgA1 proteases].

    PubMed

    Amelina, I P; Zakharova, N A

    1984-12-01

    Sufficiently purified IgA, subclass I, has been isolated from the defibrinated plasma of a myeloma patient by chromatography on columns packed with DEAE-Sephadex A-50 or Sephadex G-200, and rabbit antiserum to this immunoglobulin has been obtained. These preparations have been used for detecting specific protease in Bordetella pertussis. The tested B. pertussis strains have been shown to induce, as revealed by immunoelectrophoretic methods, the proteolysis of human IgA, subclass I.

  17. TBK1 controls IgA class switching by negatively regulating noncanonical NF-κB signaling

    PubMed Central

    Jin, Jin; Xiao, Yichuan; Chang, Jae-Hoon; Yu, Jiayi; Hu, Hongbo; Starr, Robyn; Brittain, George C.; Chang, Mikyoung; Cheng, Xuhong; Sun, Shao-Cong

    2012-01-01

    Immunoglobulin (Ig) class switching is crucial for generating antibody diversity in humoral immunity and, if deregulated, also has severe pathological consequences. How the magnitude of Ig isotype switching is controlled is still poorly understood. Here we identify TANK-binding kinase 1 (TBK1) as a pivotal negative regulator of IgA class switching. B cell-specific TBK1 ablation in mice resulted in uncontrolled production of IgA and development of nephropathy-like disease symptoms. TBK1 negatively regulated IgA class switching by attenuating noncanonical NF-κB signaling, an action that involved TBK1-mediated phosphorylation and subsequent degradation of the NF-κB-inducing kinase. These findings establish TBK1 as a pivotal negative regulator of the noncanonical NF-κB pathway and highlight a unique mechanism that controls IgA production. PMID:23023393

  18. GWAS for serum galactose-deficient IgA1 implicates critical genes of the O-glycosylation pathway

    PubMed Central

    Kiryluk, Krzysztof; Moldoveanu, Zina; Suzuki, Hitoshi; Reily, Colin; Hou, Ping; Xie, Jingyuan; Mladkova, Nikol; Prakash, Sindhuri; Fischman, Clara; Shapiro, Samantha; Bradbury, Drew; Ionita-Laza, Iuliana; Eitner, Frank; Rauen, Thomas; Maillard, Nicolas; Floege, Jürgen; Chen, Nan; Zhang, Hong; Scolari, Francesco; Wyatt, Robert J.; Julian, Bruce A.; Gharavi, Ali G.; Novak, Jan

    2017-01-01

    Aberrant O-glycosylation of serum immunoglobulin A1 (IgA1) represents a heritable pathogenic defect in IgA nephropathy, the most common form of glomerulonephritis worldwide, but specific genetic factors involved in its determination are not known. We performed a quantitative GWAS for serum levels of galactose-deficient IgA1 (Gd-IgA1) in 2,633 subjects of European and East Asian ancestry and discovered two genome-wide significant loci, in C1GALT1 (rs13226913, P = 3.2 x 10−11) and C1GALT1C1 (rs5910940, P = 2.7 x 10−8). These genes encode molecular partners essential for enzymatic O-glycosylation of IgA1. We demonstrated that these two loci explain approximately 7% of variability in circulating Gd-IgA1 in Europeans, but only 2% in East Asians. Notably, the Gd-IgA1-increasing allele of rs13226913 is common in Europeans, but rare in East Asians. Moreover, rs13226913 represents a strong cis-eQTL for C1GALT1 that encodes the key enzyme responsible for the transfer of galactose to O-linked glycans on IgA1. By in vitro siRNA knock-down studies, we confirmed that mRNA levels of both C1GALT1 and C1GALT1C1 determine the rate of secretion of Gd-IgA1 in IgA1-producing cells. Our findings provide novel insights into the genetic regulation of O-glycosylation and are relevant not only to IgA nephropathy, but also to other complex traits associated with O-glycosylation defects, including inflammatory bowel disease, hematologic disease, and cancer. PMID:28187132

  19. Photoinduced release of Zn2+ with ZinCleav-1: a nitrobenzyl-based caged complex.

    PubMed

    Bandara, H M Dhammika; Kennedy, Daniel P; Akin, Elif; Incarvito, Christopher D; Burdette, Shawn C

    2009-09-07

    Caged complexes are metal ion chelators that release analytes when exposed to light of a specific wavelength. The synthesis and properties of ZinCleav-1, a cage for Zn(2+) that fragments upon photolysis, is reported. The general uncaging strategy involves integrating a nitrobenzyl group on the backbone of the ligand so that a carbon-heteroatom bond is cleaved by the photoreaction. The caged complex was obtained using a new synthetic strategy involving a Strecker synthesis to prepare a key aldehyde intermediate. ZinCleav-1 has a K(d) of 0.23 pM for Zn(2+) as measured by competitive titration with [Zn(PAR)(2)] (PAR = 4-(2-pyridyl-2-azo) resorcinol). The quantum yield for ZinCleav-1 is 2.4% and 0.55% for the apo and Zn(2+) complex, respectively. The ability of ZinCleav-1 to increase free [Zn(2+)] is calculated theoretically using the binding constants for the uncaged photoproducts, and demonstrated practically by using a fluorescent sensor to image the liberated Zn(2+). Free Zn(2+) may function as a neurotransmitter and have a role in the pathology of several neurological diseases. Studying these physiological functions remains challenging because Zn(2+) is silent to most common spectroscopic techniques. We expect ZinCleav-1 to be the first in a class of caged complexes that will facilitate biological investigations.

  20. Structure and mechanism of NOV1, a resveratrol-cleaving dioxygenase

    DOE PAGES

    McAndrew, Ryan P.; Sathitsuksanoh, Noppadon; Mbughuni, Michael M.; ...

    2016-11-30

    Stilbenes are diphenyl ethene compounds produced naturally in a wide variety of plant species and some bacteria. Stilbenes are also derived from lignin during kraft pulping. Stilbene cleavage oxygenases (SCOs) cleave the central double bond of stilbenes, forming two phenolic aldehydes. Here in this paper, we report the structure of an SCO. The X-ray structure of NOV1 from Novosphingobium aromaticivorans was determined in complex with its substrate resveratrol (1.89 Å), its product vanillin (1.75 Å), and without any bound ligand (1.61 Å). The enzyme is a seven-bladed β-propeller with an iron cofactor coordinated by four histidines. In all three structures,more » dioxygen is observed bound to the iron in a side-on fashion. These structures, along with EPR analysis, allow us to propose a mechanism in which a ferric-superoxide reactswith substrate activated by deprotonation of a phenol group at position 4 of the substrate, which allows movement of electron density toward the central double bond and thus facilitates reaction with the ferric superoxide electrophile. Correspondingly, NOV1 cleaves a wide range of other stilbene-like compounds with a 4'-OH group, offering potential in processing some solubilized fragments of lignin into monomer aromatic compounds.« less

  1. CagA, a major virulence factor of Helicobacter pylori, promotes the production and underglycosylation of IgA1 in DAKIKI cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Man; Li, Fu-gang; Xie, Xi-sheng

    Highlights: • CagA stimulated cell proliferation and the production of IgA1 in DAKIKI cells. • CagA promoted the underglycosylation of IgA1 in DAKIKI cells. • CagA decreased the expression of C1GALT1 and its chaperone Cosmc in DAKIKI cells. • Helicobacter pylori infection may participate in the pathogenesis of IgAN via CagA. - Abstract: While Helicobacter pylori (Hp) infection is closely associated with IgA nephropathy (IgAN), the underlying molecular mechanisms remain to be elucidated. This study was to investigate the effect of cytotoxin associated gene A protein (CagA), a major virulence factor of Hp, on the production and underglycosylation of IgA1more » in the B cell line DAKIKI cells. Cells were cultured and treated with recombinant CagA protein. We found that CagA stimulated cell proliferation and the production of IgA1 in a dose-dependent and time-dependent manner. Moreover, CagA promoted the underglycosylation of IgA1, which at least partly attributed to the downregulation of β1,3-galactosyltransferase (C1GALT1) and its chaperone Cosmc. In conclusion, we demonstrated that Hp infection, at least via CagA, may participate in the pathogenesis of IgAN by influencing the production and glycosylation of IgA1 in B cells.« less

  2. Plasmin-Cleaved β-2-Glycoprotein 1 Is an Inhibitor of Angiogenesis

    PubMed Central

    Sakai, Taro; Balasubramanian, Krishnakumar; Maiti, Sourindra; Halder, Jyotsna B.; Schroit, Alan J.

    2007-01-01

    β-2-Glycoprotein 1, an abundant plasma glycoprotein, binds anionic cell surfaces and functions as a regulator of thrombosis. Here, we show that cleavage of the kringle domain at Lys317/Thr318 switches its function to a regulator of angiogenesis. In vitro, the cleaved protein specifically inhibited the proliferation and migration of endothelial cells. The protein was without effect on preformed endothelial cell tubes. In vivo, the cleaved protein inhibited neovascularization into subcutaneously implanted Matrigel and Gelfoam sponge implants and the growth of orthotopically injected tumors. Collectively, these data indicate that plasmin-cleaved β-2-glycoprotein 1 is a potent antiangiogenic and antitumor molecule of potential therapeutic significance. PMID:17872974

  3. Insulin-like growth factor binding protein-1 levels are increased in patients with IgA nephropathy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tokunaga, Koki; Uto, Hirofumi, E-mail: hirouto@m2.kufm.kagoshima-u.ac.jp; Takami, Yoichiro

    2010-08-20

    Research highlights: {yields} IGFBP-1 mRNA over express in kidneys obtained from mice model of IgA nephropathy. {yields} Serum IGFBP-1 levels are high in patients with IgA nephropathy. {yields} Serum IGFBP-1 levels correlate with renal function and the severity of renal injury. -- Abstract: The mechanisms underlying the pathogenesis of immunoglobulin A (IgA) nephropathy (IgAN) are not well understood. In this study, we examined gene expression profiles in kidneys obtained from mice with high serum IgA levels (HIGA mice), which exhibit features of human IgAN. Female inbred HIGA, established from the ddY line, were used in these experiments. Serum IgA levels,more » renal IgA deposition, mesangial proliferation, and glomerulosclerosis were increased in 32-week-old HIGA mice in comparison to ddY animals. By microarray analysis, five genes were observed to be increased by more than 2.5-fold in 32-week-old HIGA in comparison to 16-week-old HIGA; these same five genes were decreased more than 2.5-fold in 32-week-old ddY in comparison to 16-week-old ddY mice. Of these five genes, insulin-like growth factor (IGF) binding protein (IGFBP)-1 exhibited differential expression between these mouse lines, as confirmed by quantitative RT-PCR. In addition, serum IGFBP-1 levels were significantly higher in patients with IgAN than in healthy controls. In patients with IgAN, these levels correlated with measures of renal function, such as estimated glomerular filtration rate (eGFR), but not with sex, age, serum IgA, C3 levels, or IGF-1 levels. Pathologically, serum IGFBP-1 levels were significantly associated with the severity of renal injury, as assessed by mesangial cell proliferation and interstitial fibrosis. These results suggest that increased IGFBP-1 levels are associated with the severity of renal pathology in patients with IgAN.« less

  4. IgA Enhances IGF-1 Mitogenic Activity Via Receptor Modulation in Glomerular Mesangial Cells: Implications for IgA-Induced Nephropathy.

    PubMed

    Al-Eisa, Amal; Dhaunsi, Gursev S

    2017-01-01

    Glomerulonephritis due to mesangial proliferation is responsible for renal dysfunction in IgA nephropathy (IgAN), however molecular mechanisms of pathogenesis are not well known. We examined the effect of IgA on Insulin-like Growth Factor-1 (IGF-1) activity, a potent mitogen with vital role in growth and development of children, and IGF-1 receptor (IGF-1R) in cultures of glomerular mesangial cells (GMC). GMC were isolated from rat kidneys using sieving and enzymatic digestion of tissue homogenates, and cultured in RPMI 1640 medium. GMC cultures were treated with IgA (0-10 µg/ml) in the presence or absence of IGF-1 and fetal bovine serum (FBS), and BrdU incorporation was measured. IGF-1 levels were assayed along with real-time PCR quantification of IGF-1R mRNA. Treatment of GMC with IgA (5 -10 µg/ml) significantly (p < 0.01) increased the BrdU incorporation in the presence or absence of FBS or IGF-1. IgA-mediated effects were more pronounced in IGF-1 treated cells that were significantly (p < 0.01) blocked by pretreatment of cells with IGF-1 receptor antibody or genistein. IgA significantly increased the levels of IGF-1 in culture supernatants and GMC homogenates. IGF-1R mRNA was significantly (p < 0.01) increased in IgA treated cells particularly by co-treatment with IGF-1. These findings show that IgA enhances the IGF-1 activity in GMC via stimulation of IGF-1R gene transcription and suggest a role for IGF-1 in pathogenesis of IgAN. © 2017 The Author(s). Published by S. Karger AG, Basel.

  5. Association of IgG co-deposition with serum levels of galactose-deficient IgA1 in pediatric IgA nephropathy

    PubMed Central

    Eison, T. Matthew; Hastings, M. Colleen; Moldoveanu, Zina; Sanders, John T.; Gaber, Lillian; Walker, Patrick D.; Lau, Keith K; Julian, Bruce A.; Novak, Jan; Wyatt, Robert J.

    2012-01-01

    Objective: To determine whether the absence of mesangial IgG deposits is associated with the absence of elevated blood levels of galactose-deficient IgA1 (Gd-IgA1) in pediatric patients with IgA nephropathy (IgAN). Design and methods: Serum Gd-IgA1 levels were determined by ELISA using an N-acetylgalactosamine-specific lectin from Helix aspersa. Levels of Gd-IgA1 above the 90th percentile for healthy pediatric controls were considered to be elevated. Renal biopsy samples were examined by immunofluorescence for presence and intensity of staining for IgA, IgG, IgM, C3 and C1q and by light microscopy for histological changes. Findings were graded by a single pathologist (L. Gaber) at UTHSC until 2007 and by NephropathTM (Little Rock, AR, USA) thereafter. Staining for the mesangial deposits was considered negative when intensity was trace or less, and positive at greater intensity. Fisher’s exact-test was used to determine significance of 2 × 2 tables. Results: Serum samples were obtained from 30 patients with IgAN diagnosed before age 18 years. Male : female ratio was 2.3 : 1. Twenty were Caucasian and 10 were African-American. Blood was obtained within 3 months of biopsy (incident cases) for 12, while 18 provided blood > 3 months after biopsy (prevalent cases). Serum Gd-IgA1 level was elevated in 23 (77%) of cases and 20 (67%) had a biopsy positive for IgG. Of those 20 patients, 18 (90%) had an elevated serum Gd-IgA1 level, whereas 5 (50%) of patients with biopsies without IgG had a normal serum Gd-IgA1 level (p = 0.026). Summary: In this small study we found a weak association between the absence of IgG in the biopsy and normal serum Gd-IgA1 level. PMID:23006340

  6. Induction of mucosal IgA by a novel jet delivery technique for HIV-1 DNA.

    PubMed

    Lundholm, P; Asakura, Y; Hinkula, J; Lucht, E; Wahren, B

    1999-04-09

    Novel ways of delivering plasmid DNA to elicit humoral IgA, IgG and cell-mediated immune responses in mice were investigated. Intraoral administration of DNA in the cheek, using a jet immunization technique, elicited the highest IgA mucosal responses. Intranasal immunization gave strong mucosal IgA responses and persistent systemic IgG. Immunoglobulin isotype analysis revealed an IgG1 profile for intramuscular tongue and gene gun immunizations and an IgG2a profile following oral jet injection and intranasal application. The route of delivery was of importance for the characteristics and quality of the mucosal immune response following DNA immunization. For DNA vaccine delivery, the intraoral jet injection technique has the advantages of being a simple and rapid way of administering the DNA in solution and of provoking specific mucosal IgA when administered in the mucosal associated lymphoid tissue.

  7. Separation of Two Distinct O-Glycoforms of Human IgA1 by Serial Lectin Chromatography Followed by Mass Spectrometry O-Glycan Analysis.

    PubMed

    Lehoux, S; Ju, T

    2017-01-01

    Human immunoglobulin A1 (IgA1), which carries four to six mucin-type O-glycans (O-glycans) on its hinge region (HR), is the most abundant O-glycoprotein in plasma or serum. While normal O-glycans from hematopoietic-originated cells are core 1-based complex structures, many reports showed that the IgA1 from patients with IgA nephropathy (IgAN) carries undergalactosylated or truncated O-glycans such as the Tn antigen and its sialylated version the SialylTn (STn) antigen on the HR. Yet, there is still a debate whether Tn/STn on the HR of IgA1 is specific to the IgA1 from patients with IgAN since these antigens have also been seen in serum IgA1 of healthy individuals. An additional question is whether the O-glycans at all sites on the two HRs of one IgA1 molecule are homogeneous (either all normal or all Tn/STn) or heterogeneous (both normal and Tn/STn O-glycans). To address these questions, we conducted a systematic study on the O-glycans of plasma IgA1 from both IgAN patients and healthy controls using serial HPA and PNA lectin chromatography followed by western blotting and further analysis of O-glycans from HPA-bound and PNA-bound IgA1 fractions by mass spectrometry. Unexpectedly, we found that a variable minor fraction of IgA1 from both IgAN patients and healthy controls had Tn/STn antigens, and that the O-glycoprotein IgA1 molecules from most samples had only two distinct O-glycoforms: one major glycoform with homogeneous normal core 1-based O-glycans and one minor glycoform with homogeneous Tn/STn antigens. These results raised a serious question about the role of Tn/STn antigens on IgA1 in pathogenesis of IgAN, and there is a demand for a practical methodology that any laboratory can utilize to analyze the O-glycans of IgA1. Herein, we describe the methodology we developed in more detail. The method could also be applied to the analysis of any other O-glycosylated proteins. © 2017 Elsevier Inc. All rights reserved.

  8. Inhibition of Prevotella and Capnocytophaga immunoglobulin A1 proteases by human serum.

    PubMed

    Frandsen, E V; Kjeldsen, M; Kilian, M

    1997-07-01

    Oral Prevotella and Capnocytophaga species, regularly isolated from periodontal pockets and associated with extraoral infections, secret specific immunoglobulin A1 (IgA1) proteases cleaving human IgA1 in the hinge region into intact Fab and Fc fragments. To investigate whether these enzymes are subject to inhibition in vivo in humans, we tested 34 sera from periodontally diseased and healthy individuals in an enzyme-linked immunosorbent assay for the presence and titers of inhibition of seven Prevotella and Capnocytophaga proteases. All or nearly all of the sera inhibited the IgA1 protease activity of Prevotella buccae, Prevotella oris, and Prevotella loescheii. A minor proportion of the sera inhibited Prevotella buccalis, Prevotella denticola, and Prevotella melaninogenica IgA1 proteases, while no sera inhibited Capnocytophaga ochracea IgA1 protease. All inhibition titers were low, ranging from 5 to 55, with titer being defined as the reciprocal of the dilution of serum causing 50% inhibition of one defined unit of protease activity. No correlation between periodontal disease status and the presence, absence, or titer of inhibition was observed. The nature of the low titers of inhibition in all sera of the IgA1 proteases of P. buccae, P. oris, and P. loescheii was further examined. In size exclusion chromatography, inhibitory activity corresponded to the peak volume of IgA. Additional inhibition of the P. oris IgA1 protease was found in fractions containing both IgA and IgG. Purification of the IgG fractions of five sera by passage of the sera on a protein G column resulted in recovery of inhibitory IgG antibodies against all three IgA1 proteases, with the highest titer being for the P. oris enzyme. These finding indicate that inhibitory activity is associated with enzyme-neutralizing antibodies.

  9. Inhibition of Prevotella and Capnocytophaga immunoglobulin A1 proteases by human serum.

    PubMed Central

    Frandsen, E V; Kjeldsen, M; Kilian, M

    1997-01-01

    Oral Prevotella and Capnocytophaga species, regularly isolated from periodontal pockets and associated with extraoral infections, secret specific immunoglobulin A1 (IgA1) proteases cleaving human IgA1 in the hinge region into intact Fab and Fc fragments. To investigate whether these enzymes are subject to inhibition in vivo in humans, we tested 34 sera from periodontally diseased and healthy individuals in an enzyme-linked immunosorbent assay for the presence and titers of inhibition of seven Prevotella and Capnocytophaga proteases. All or nearly all of the sera inhibited the IgA1 protease activity of Prevotella buccae, Prevotella oris, and Prevotella loescheii. A minor proportion of the sera inhibited Prevotella buccalis, Prevotella denticola, and Prevotella melaninogenica IgA1 proteases, while no sera inhibited Capnocytophaga ochracea IgA1 protease. All inhibition titers were low, ranging from 5 to 55, with titer being defined as the reciprocal of the dilution of serum causing 50% inhibition of one defined unit of protease activity. No correlation between periodontal disease status and the presence, absence, or titer of inhibition was observed. The nature of the low titers of inhibition in all sera of the IgA1 proteases of P. buccae, P. oris, and P. loescheii was further examined. In size exclusion chromatography, inhibitory activity corresponded to the peak volume of IgA. Additional inhibition of the P. oris IgA1 protease was found in fractions containing both IgA and IgG. Purification of the IgG fractions of five sera by passage of the sera on a protein G column resulted in recovery of inhibitory IgG antibodies against all three IgA1 proteases, with the highest titer being for the P. oris enzyme. These finding indicate that inhibitory activity is associated with enzyme-neutralizing antibodies. PMID:9220164

  10. Label Free QCM Immunobiosensor for AFB1 Detection Using Monoclonal IgA Antibody as Recognition Element.

    PubMed

    Ertekin, Özlem; Öztürk, Selma; Öztürk, Zafer Ziya

    2016-08-11

    This study introduces the use of an IgA isotype aflatoxin (AF) specific monoclonal antibody for the development of a highly sensitive Quartz Crystal Microbalance (QCM) immunobiosensor for the detection of AF in inhibitory immunoassay format. The higher molecular weight of IgA antibodies proved an advantage over commonly used IgG antibodies in label free immunobiosensor measurements. IgA and IgG antibodies with similar affinity for AF were used in the comparative studies. Sensor surface was prepared by covalent immobilization of AFB1, using self assembled monolayer (SAM) formed on gold coated Quartz Crystal, with 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxy succinimide (EDC/NHS) method using a diamine linker. Nonspecific binding to the surface was decreased by minimizing the duration of EDC/NHS activation. Sensor surface was chemically blocked after AF immobilization without any need for protein blocking. This protein free sensor chip endured harsh solutions with strong ionic detergent at high pH, which is required for the regeneration of the high affinity antibody-antigen interaction. According to the obtained results, the detection range with IgA antibodies was higher than IgG antibodies in QCM immunosensor developed for AFB1.

  11. Label Free QCM Immunobiosensor for AFB1 Detection Using Monoclonal IgA Antibody as Recognition Element

    PubMed Central

    Ertekin, Özlem; Öztürk, Selma; Öztürk, Zafer Ziya

    2016-01-01

    This study introduces the use of an IgA isotype aflatoxin (AF) specific monoclonal antibody for the development of a highly sensitive Quartz Crystal Microbalance (QCM) immunobiosensor for the detection of AF in inhibitory immunoassay format. The higher molecular weight of IgA antibodies proved an advantage over commonly used IgG antibodies in label free immunobiosensor measurements. IgA and IgG antibodies with similar affinity for AF were used in the comparative studies. Sensor surface was prepared by covalent immobilization of AFB1, using self assembled monolayer (SAM) formed on gold coated Quartz Crystal, with 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxy succinimide (EDC/NHS) method using a diamine linker. Nonspecific binding to the surface was decreased by minimizing the duration of EDC/NHS activation. Sensor surface was chemically blocked after AF immobilization without any need for protein blocking. This protein free sensor chip endured harsh solutions with strong ionic detergent at high pH, which is required for the regeneration of the high affinity antibody-antigen interaction. According to the obtained results, the detection range with IgA antibodies was higher than IgG antibodies in QCM immunosensor developed for AFB1. PMID:27529243

  12. Lack of galectin-3 up-regulates IgA expression by peritoneal B1 lymphocytes during B cell differentiation.

    PubMed

    Oliveira, Felipe L; Bernardes, Emerson S; Brand, Camila; dos Santos, Sofia N; Cabanel, Mariana P; Arcanjo, Kátia D; Brito, José M; Borojevic, Radovan; Chammas, Roger; El-Cheikh, Márcia C

    2016-02-01

    Galectin-3 is a β-galactoside-binding protein with an inhibitory role in B cell differentiation into plasma cells in distinct lymphoid tissues. We use a model of chronic schistosomiasis, a well-characterized experimental disease hallmarked by polyclonal B cell activation, in order to investigate the role of galectin-3 in controlling IgA production through peritoneal B1 cells. Chronically infected, galectin-3-deficient mice (Lgals3(-/-)) display peritoneal fluid hypercellularity, increased numbers of atypical peritoneal IgM(+)/IgA(+) B1a and B1b lymphocytes and histological disturbances in plasma cell niches when compared with Lgals3(+/+) mice. Similar to our infection model, peritoneal B1 cells from uninfected Lgals3(-/-) mice show enhanced switching to IgA after in vitro treatment with interleukin-5 plus transforming growth factor-β (IL-5 + TGF-β1). A higher number of IgA(+) B1a lymphocytes was found in the peritoneal cavity of Lgals3(-/-)-uninfected mice at 1 week after i.p. injection of IL-5 + TGF-β1; this correlates with the increased levels of secreted IgA detected in the peritoneal fluid of these mice after cytokine treatment. Interestingly, a higher number of degranulated mast cells is present in the peritoneal cavity of uninfected and Schistosoma mansoni-infected Lgals3(-/-) mice, indicating that, at least in part, mast cells account for the enhanced differentiation of B1 into IgA-producing B cells found in the absence of galectin-3. Thus, a novel role is revealed for galectin-3 in controlling the expression of surface IgA by peritoneal B1 lymphocytes; this might have important implications for manipulating the mucosal immune response.

  13. Serum anti-phenolic glycolipid-1 IgA correlates to IgM isotype in leprosy patients: a possible candidate for seroepidemiological surveys?

    PubMed

    de Macedo, Alexandre C; Guimarães, Juliana A; Rodrigues, Raphael O; Araújo, Thiago D V; Tavares, Clodis M; Cabral, Paula B; de Moraes-Pinto, Maria Isabel; Nagao-Dias, Aparecida T

    2018-03-01

    The aim of this study was to compare serum anti-phenolic glycolipid-1 IgA, IgG, and IgM levels in leprosy patients and controls. Analysis of anti-PGL-1 IgA, IgG, or IgM in serum samples from multibacillary (MB, n=32) and paucibacillary (PB, n=22) leprosy patients, and in non-endemic controls (n=17), using an indirect enzyme-linked immunosorbent assay. A strong correlation between serum IgM and IgA isotypes was found (r=.745, P<.0001) in MB patients. A moderate correlation was found in all analyses in PB patients. A moderate agreement was found between anti-PGL1 IgA and IgM tests. Based on the ROC curves, the cut-off values were selected and the parameters of validation were calculated. Considering the clinical forms altogether, the diagnostic sensitivities were 50.0% for IgA, 22.2% for IgG, and 74.1% for IgM. The positive (VPP) and negative (VPN) predictive values were estimated for each isotype. For IgA, the VPP and VPN were, respectively, 100.0% (87.0%-100.0%; 95% confidence interval) and 38.7% (24.4%-54.5%); for IgG, 100% (87.0%-100.0%) and 28.8% (17.8%-42.1%), respectively; and for IgM, 95.2% (83.8%-99.4%) and 51.7% (32.5%-70.6%), respectively. Despite the limiting factors, anti-PGL1 IgA correlates to IgM levels and it could be considered as a possible laboratorial tool to be also used, for instance, in serological follow-up studies. © 2017 Wiley Periodicals, Inc.

  14. Vaccine-Induced Plasma IgA Specific for the C1 Region of the HIV-1 Envelope Blocks Binding and Effector Function of IgG

    DTIC Science & Technology

    2013-05-28

    uninfected vaccine recipients in RV144. Moreover, Env-specific IgA antibodies from RV144 vaccinees blocked the binding of ADCC-mediating mAb to HIV-1 Env... vaccine re- cipients in the case control study. There was a significantly greater number of infected vaccinees with IgA/IgG ratio >1e-02 (A1 Congp140 Env... vaccine efficacy. Second, we demonstrated that IgA mAbs isolated from RV144 vaccinees can both inhibit Env binding and block ADCC function of vaccine

  15. Oral Administration of β-1,3/1,6-Glucan to Dogs Temporally Changes Total and Antigen-Specific IgA and IgM▿

    PubMed Central

    Stuyven, E.; Verdonck, F.; Van Hoek, I.; Daminet, S.; Duchateau, L.; Remon, J. P.; Goddeeris, B. M.; Cox, E.

    2010-01-01

    The effect of oral administration of β-1,3/1,6-glucans from Saccharomyces cerevisiae on humoral immunity in domestic dogs is not known. In this study, 15 beagle dogs were orally given MacroGard tablets, which contain 150 mg of this β-glucan, daily for 4 weeks. At the end of this period, the total serum immunoglobulin A (IgA) level decreased significantly in the group treated with the glucan compared to that in the control group as well as compared to the concentrations before supplementation. In contrast, the total serum IgM level rose significantly, whereas no effect on the IgG level occurred. Similar changes were seen in Bordetella-specific IgA and IgM titers following vaccination during the supplementation period. The IgA concentration also became significantly lower in the saliva and tears of the glucan group than in the placebo group. The effects disappeared 1 week after the cessation of the supplementation. In conclusion, the results showed a temporary change in the isotype profile during glucan supplementation. PMID:20032218

  16. Neutralization Takes Precedence Over IgG or IgA Isotype-related Functions in Mucosal HIV-1 Antibody-mediated Protection.

    PubMed

    Astronomo, Rena D; Santra, Sampa; Ballweber-Fleming, Lamar; Westerberg, Katharine G; Mach, Linh; Hensley-McBain, Tiffany; Sutherland, Laura; Mildenberg, Benjamin; Morton, Georgeanna; Yates, Nicole L; Mize, Gregory J; Pollara, Justin; Hladik, Florian; Ochsenbauer, Christina; Denny, Thomas N; Warrier, Ranjit; Rerks-Ngarm, Supachai; Pitisuttithum, Punnee; Nitayapan, Sorachai; Kaewkungwal, Jaranit; Ferrari, Guido; Shaw, George M; Xia, Shi-Mao; Liao, Hua-Xin; Montefiori, David C; Tomaras, Georgia D; Haynes, Barton F; McElrath, Juliana M

    2016-12-01

    HIV-1 infection occurs primarily through mucosal transmission. Application of biologically relevant mucosal models can advance understanding of the functional properties of antibodies that mediate HIV protection, thereby guiding antibody-based vaccine development. Here, we employed a human ex vivo vaginal HIV-1 infection model and a rhesus macaque in vivo intrarectal SHIV challenge model to probe the protective capacity of monoclonal broadly-neutralizing (bnAb) and non-neutralizing Abs (nnAbs) that were functionally modified by isotype switching. For human vaginal explants, we developed a replication-competent, secreted NanoLuc reporter virus system and showed that CD4 binding site bnAbs b12 IgG1 and CH31 IgG1 and IgA2 isoforms potently blocked HIV-1 JR-CSF and HIV-1 Bal26 infection. However, IgG1 and IgA nnAbs, either alone or together, did not inhibit infection despite the presence of FcR-expressing effector cells in the tissue. In macaques, the CH31 IgG1 and IgA2 isoforms infused before high-dose SHIV challenge were completely to partially protective, respectively, while nnAbs (CH54 IgG1 and CH38 mIgA2) were non-protective. Importantly, in both mucosal models IgG1 isotype bnAbs were more protective than the IgA2 isotypes, attributable in part to greater neutralization activity of the IgG1 variants. These findings underscore the importance of potent bnAb induction as a primary goal of HIV-1 vaccine development. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. IgE, IgG4 and IgA specific to Bet v 1-related food allergens do not predict oral allergy syndrome.

    PubMed

    Guhsl, E E; Hofstetter, G; Lengger, N; Hemmer, W; Ebner, C; Fröschl, R; Bublin, M; Lupinek, C; Breiteneder, H; Radauer, C

    2015-01-01

    Birch pollen-associated plant food allergy is caused by Bet v 1-specific IgE, but presence of cross-reactive IgE to related allergens does not predict food allergy. The role of other immunoglobulin isotypes in the birch pollen-plant food syndrome has not been investigated in detail. Bet v 1-sensitized birch pollen-allergic patients (n = 35) were diagnosed for food allergy by standardized interviews, skin prick tests, prick-to-prick tests and ImmunoCAP. Concentrations of allergen-specific IgE, IgG1, IgG4 and IgA to seven Bet v 1-related food allergens were determined by ELISA. Bet v 1, Cor a 1, Mal d 1 and Pru p 1 bound IgE from all and IgG4 and IgA from the majority of sera. Immunoglobulins to Gly m 4, Vig r 1 and Api g 1.01 were detected in <65% of the sera. No significant correlation was observed between plant food allergy and increased or reduced levels of IgE, IgG1, IgG4 or IgA specific to most Bet v 1-related allergens. Api g 1-specific IgE was significantly (P = 0.01) elevated in celeriac-allergic compared with celeriac-tolerant patients. Likewise, frequencies of IgE (71% vs 15%; P = 0.01) and IgA (86% vs 38%; P = 0.04) binding to Api g 1.01 were increased. Measurements of allergen-specific immunoglobulins are not suitable for diagnosing Bet v 1-mediated plant food allergy to hazelnut and Rosaceae fruits. In contrast, IgE and IgA to the distantly related allergen Api g 1 correlate with allergy to celeriac. © 2014 The Authors. Allergy Published by John Wiley & Sons Ltd.

  18. New insights into the pathogenesis of IgA nephropathy.

    PubMed

    Yeo, See Cheng; Cheung, Chee Kay; Barratt, Jonathan

    2018-05-01

    IgA nephropathy is the most common form of glomerulonephritis in many parts of the world and remains an important cause of end-stage renal disease. Current evidence suggests that IgA nephropathy is not due to a single pathogenic insult, but rather the result of multiple sequential pathogenic "hits". An abnormally increased level of circulating poorly O-galactosylated IgA1 and the production of O-glycan-specific antibodies leads to the formation of IgA1-containing immune complexes, and their subsequent mesangial deposition results in inflammation and glomerular injury. While this general framework has formed the foundation of our current understanding of the pathogenesis of IgA nephropathy, much work is ongoing to try to precisely define the genetic, epigenetic, immunological, and molecular basis of IgA nephropathy. In particular, the precise origin of poorly O-galactosylated IgA1 and the inciting factors for the production of O-glycan-specific antibodies continue to be intensely evaluated. The mechanisms responsible for mesangial IgA1 deposition and subsequent renal injury also remain incompletely understood. In this review, we summarize the current understanding of the key steps involved in the pathogenesis of IgA nephropathy. It is hoped that further advances in our understanding of this common glomerulonephritis will lead to novel diagnostic and prognostic biomarkers, and targeted therapies to ameliorate disease progression.

  19. γ-secretase composed of PS1/Pen2/Aph1a can cleave Notch and APP in the absence of Nicastrin

    PubMed Central

    Zhao, Guojun; Liu, Zhenyi; Ilagan, Ma. Xenia G.; Kopan, Raphael

    2010-01-01

    γ-secretase is a multiprotein intramembrane-cleaving protease with a growing list of protein substrates including the Notch receptors and the amyloid precursor protein. The four components of γ-secretase complex - presenilin (PS), nicastrin (NCT), Pen2, and Aph1 - are all thought to be essential for activity. The catalytic domain resides within PS proteins; NCT has been suggested to be critical for substrate recognition; the contributions of Pen2 and Aph1 remain unclear. The role of NCT has been challenged recently by the observation that a critical residue (E332) in NCT, thought to be essential for γ-secretase activity, is instead involved in complex maturation. Here we report that NCT is dispensable for γ-secretase activity. NCT-independent γ-secretase activity can be detected in two independent NCT-deficient MEF lines, and blocked by the γ-secretase inhibitors DAPT and L-685,458. This catalytic activity requires prior ectodomain shedding of the substrate, and can cleave ligand-activated endogenous Notch receptors, indicating presence at the plasma membrane. siRNA knockdown experiments demonstrated that NCT-independent γ-secretase activity requires the presence of PS1, Pen2 and Aph1a but can tolerate knockdown of PS2 or Aph1b. We conclude that a PS1/Pen2/Aph1a trimeric complex is an active enzyme, displaying similar biochemical properties to those of γ-secretase and roughly 50% of its activity when normalized to PS1 NTF levels. This PS1/Pen2/Aph1a complex, however, is highly unstable. Thus, NCT acts to stabilize γ-secretase, but is not required for substrate recognition. PMID:20130175

  20. Comparison of Antiviral Activity between IgA and IgG Specific to Influenza Virus Hemagglutinin: Increased Potential of IgA for Heterosubtypic Immunity

    PubMed Central

    Yokoyama, Ayaka; Miyamoto, Hiroko; Kajihara, Masahiro; Maruyama, Junki; Nao, Naganori; Manzoor, Rashid; Takada, Ayato

    2014-01-01

    Both IgA and IgG antibodies are known to play important roles in protection against influenza virus infection. While IgG is the major isotype induced systemically, IgA is predominant in mucosal tissues, including the upper respiratory tract. Although IgA antibodies are believed to have unique advantages in mucosal immunity, information on direct comparisons of the in vitro antiviral activities of IgA and IgG antibodies recognizing the same epitope is limited. In this study, we demonstrate differences in antiviral activities between these isotypes using monoclonal IgA and IgG antibodies obtained from hybridomas of the same origin. Polymeric IgA-producing hybridoma cells were successfully subcloned from those originally producing monoclonal antibody S139/1, a hemaggulutinin (HA)-specific IgG that was generated against an influenza A virus strain of the H3 subtype but had cross-neutralizing activities against the H1, H2, H13, and H16 subtypes. These monoclonal S139/1 IgA and IgG antibodies were assumed to recognize the same epitope and thus used to compare their antiviral activities. We found that both S139/1 IgA and IgG antibodies strongly bound to the homologous H3 virus in an enzyme-linked immunosorbent assay, and there were no significant differences in their hemagglutination-inhibiting and neutralizing activities against the H3 virus. In contrast, S139/1 IgA showed remarkably higher cross-binding to and antiviral activities against H1, H2, and H13 viruses than S139/1 IgG. It was also noted that S139/1 IgA, but not IgG, drastically suppressed the extracellular release of the viruses from infected cells. Electron microscopy revealed that S139/1 IgA deposited newly produced viral particles on the cell surface, most likely by tethering the particles. These results suggest that anti-HA IgA has greater potential to prevent influenza A virus infection than IgG antibodies, likely due to increased avidity conferred by its multivalency, and that this advantage may be

  1. [A case of IgA2-lambda type M-protein that IgA concentration differs from the values of M-protein by serum protein electrophoresis].

    PubMed

    Fukushima, M; Sugano, M; Ichikawa, T; Honda, T; Totsuka, M; Katsuyama, T; Fujita, K

    2001-07-01

    We report an IgA-lambda type M-protein in which the IgA concentration differed from the values of M-protein by serum protein electrophoresis found in a 53-year-old man with multiple myeloma. The M-protein value as determined by serum protein electrophoresis was 6,170 mg/dl. However, the serum IgA concentration was 3,052 mg/dl by turbidimetric immunoassay. Immuno-fixation electrophoresis using IgA subclass antisera revealed that this M-protein was the IgA2-lambda type. Western blotting analysis showed that the IgA2 molecules were composed of two approximately 68 kDa alpha 2 chains and two 28 kDa lambda chains. In addition the free lambda chain band was detected at the position of 28 kDa without 2-mercaptoethanol(2-ME) even though the patient IgA was purified. Since it is known that IgA2m(1) allotype easily release light chains from the IgA molecules in SDS-PAGE without 2-ME, we speculated that in this patient the IgA was the IgA2m(1) allotype. After peripheral blood stem cell transplantation(PBSCT), immunofixation electrophoresis of the patient serum revealed not only the bands of IgA2-lambda type M-protein, but also three bands of IgG1-kappa type M-protein in the gamma region.

  2. IgA and IgG1 reactivities assessed by flow cytometry mirror clinical aspects of infants with ocular congenital toxoplasmosis.

    PubMed

    de Jesus, Laura Néspoli Nassar Pansini; Tonini, Aline de Castro Zacche; Barros, Geisa Baptista; Coelho-dos-Reis, Jordana Grazziela A; Béla, Samantha Ribeiro; Antonelli, Lis Ribeiro do Valle; Machado, Anderson Silva; Carneiro, Ana Carolina Aguiar Vasconcelos; Andrade, Gláucia Manzan Queiroz; Vasconcelos-Santos, Daniel Vitor; Januário, José Nélio; Teixeira-Carvalho, Andréa; Vitor, Ricardo Wagner Almeida; Ferro, Eloísa A V; Mineo, José Roberto; Bahia-Oliveira, Lilian Maria Garcia; Martins-Filho, Olindo Assis; Lemos, Elenice Moreira

    2016-01-01

    This study intended to apply the flow cytometric analysis of IgA and IgG reactivity and intracytoplasmic cytokine analysis to understand and decode the clinical aspects of infants with ocular congenital toxoplasmosis. The Toxoplasma gondii-infected infants (TOXO) were subdivided according to their clinical aspects based on the absence (NRL), presence of active (ARL), active/cicatricial (ACRL) or cicatricial retinochoroidal lesions (CRL) and compared to non-infected controls (NI). The reactivity of anti-T. gondii IgG subclasses resembles the clinical aspects of ocular lesions. IgG and IgG1 discriminate infants with cicatricial lesions (ACRL and CRL) from both ARL and NLR. IgG2 and IgG3 are particularly higher in ACRL and CRL as compared to NLR. No differences were observed when IgG4 reactivity was evaluated. Thus, the results indicated that the reactivity patterns of IgA, IgG and IgG subclasses are able to discriminate ARL, ACRL and CRL from NLR or NI. IgA and IgG subclasses are relevant serological biomarkers with diagnostic and prognostic applicability, respectively. Moreover, IgA and IgG1 were closely related to cytokine production by innate/adaptive immunity cells. IgA reactivity was directly associated to TNF-α-derived from neutrophils, monocytes and CD8(+) T-cells, while IgG1 was inversely correlated with IFN-γ-producing CD4(+) and CD8(+) T-cells but positively correlated with IL-10(+) B-cells. These findings provide insights on the relationship between the cytokine production by innate/adaptive immunity and the antibody pattern of infants with ocular congenital toxoplasmosis. In addition, the present study supports the use of flow cytometric serology as a potential tool for the diagnosis and monitoring of ocular lesions in T. gondii-infected infants in the clinical setting. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Detection of IgA antibodies and quantification of IgA antibody-producing cells specific for ovalbumin or Trichinella spiralis in the rat.

    PubMed

    Van Loveren, H; Osterhaus, A D; Nagel, J; Schuurman, H J; Vos, J G

    1988-09-01

    This report describes procedures to quantify IgA responses in the rat sensitized to ovalbumin or infected with the parasite Trichinella spiralis: an ELISPOT detecting specific IgA antibody-producing cells in lymph nodes, and an ELISA demonstrating IgA antibody in serum and gut mucosal scrapings. For this purpose a mouse monoclonal anti-rat IgA antibody was produced. This IgG1-kappa 1 antibody recognized rat IgA but not rat IgM, IgG, or IgE. It proved very suitable in both assays. Using this reagent we could demonstrate large numbers of IgA anti-ovalbumin-producing cells in the mesenteric lymph nodes 15 days after sensitization to ovalbumin via the Peyer's patches. At 28 days after sensitization the numbers were much lower. IgA antibody titres to ovalbumin in serum were maximal between days 14 and 21 after immunization. Maximal numbers of IgA anti-T. spiralis-producing cells were found in the mesenteric lymph nodes 12 days after infection with muscle larvae, followed by a sharp decrease at 15 days. Maximal IgA anti-T. spiralis antibody titres in serum and mucus scrapings of small intestines were found on days 10 and 12 after oral infection with the parasite.

  4. Gluten exacerbates IgA nephropathy in humanized mice through gliadin-CD89 interaction.

    PubMed

    Papista, Christina; Lechner, Sebastian; Ben Mkaddem, Sanae; LeStang, Marie-Bénédicte; Abbad, Lilia; Bex-Coudrat, Julie; Pillebout, Evangéline; Chemouny, Jonathan M; Jablonski, Mathieu; Flamant, Martin; Daugas, Eric; Vrtovsnik, François; Yiangou, Minas; Berthelot, Laureline; Monteiro, Renato C

    2015-08-01

    IgA1 complexes containing deglycosylated IgA1, IgG autoantibodies, and a soluble form of the IgA receptor (sCD89), are hallmarks of IgA nephropathy (IgAN). Food antigens, notably gluten, are associated with increased mucosal response and IgAN onset, but their implication in the pathology remains unknown. Here, an IgAN mouse model expressing human IgA1 and CD89 was used to examine the role of gluten in IgAN. Mice were given a gluten-free diet for three generations to produce gluten sensitivity, and then challenged for 30 days with a gluten diet. A gluten-free diet resulted in a decrease of mesangial IgA1 deposits, transferrin 1 receptor, and transglutaminase 2 expression, as well as hematuria. Mice on a gluten-free diet lacked IgA1-sCD89 complexes in serum and kidney eluates. Disease severity depended on gluten and CD89, as shown by reappearance of IgAN features in mice on a gluten diet and by direct binding of the gluten-subcomponent gliadin to sCD89. A gluten diet exacerbated intestinal IgA1 secretion, inflammation, and villous atrophy, and increased serum IgA1 anti-gliadin antibodies, which correlated with proteinuria in mice and patients. Moreover, early treatment of humanized mice with a gluten-free diet prevented mesangial IgA1 deposits and hematuria. Thus, gliadin-CD89 interaction may aggravate IgAN development through induction of IgA1-sCD89 complex formation and a mucosal immune response. Hence, early-stage treatment with a gluten-free diet could be beneficial to prevent disease.

  5. Monoclonal IgA Antibodies for Aflatoxin Immunoassays

    PubMed Central

    Ertekin, Özlem; Pirinçci, Şerife Şeyda; Öztürk, Selma

    2016-01-01

    Antibody based techniques are widely used for the detection of aflatoxins which are potent toxins with a high rate of occurrence in many crops. We developed a murine monoclonal antibody of immunoglobulin A (IgA) isotype with a strong binding affinity to aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2) and aflatoxin M1 (AFM1). The antibody was effectively used in immunoaffinity column (IAC) and ELISA kit development. The performance of the IACs was compatible with AOAC performance standards for affinity columns (Test Method: AOAC 991.31). The total binding capacity of the IACs containing our antibody was 111 ng, 70 ng, 114 ng and 73 ng for AFB1, AFB2, and AFG1 andAFG2, respectively. Furthermore, the recovery rates of 5 ng of each AF derivative loaded to the IACs were determined as 104.9%, 82.4%, 85.5% and 70.7% for AFB1, AFB2, AFG1 and AFG2, respectively. As for the ELISA kit developed using non-oriented, purified IgA antibody, we observed a detection range of 2–50 µg/L with 40 min total test time. The monoclonal antibody developed in this research is hitherto the first presentation of quadruple antigen binding IgA monoclonal antibodies in mycotoxin analysis and also the first study of their utilization in ELISA and IACs. IgA antibodies are valuable alternatives for immunoassay development, in terms of both sensitivity and ease of preparation, since they do not require any orientation effort. PMID:27187470

  6. Lower serum IgA is associated with COPD exacerbation risk in SPIROMICS

    PubMed Central

    Paul, Gabriel G.; Azar, Antoine; Wise, Robert A.; O’Neal, Wanda K.; Dransfield, Mark T.; Woodruff, Prescott G.; Curtis, Jeffrey L.; Comellas, Alejandro P.; Drummond, M. Bradley; Lambert, Allison A.; Paulin, Laura M.; Fawzy, Ashraf; Kanner, Richard E.; Paine, Robert; Han, MeiLan K.; Martinez, Fernando J.; Bowler, Russell P.; Barr, R. Graham; Hansel, Nadia N.

    2018-01-01

    Background Decreased but measurable serum IgA levels (≤70 mg/dL) have been associated with risk for infections in some populations, but are unstudied in COPD. This study tested the hypothesis that subnormal serum IgA levels would be associated with exacerbation risk in COPD. Methods Data were analyzed from 1,049 COPD participants from the observational cohort study SPIROMICS (535 (51%) women; mean age 66.1 (SD 7.8), 338 (32%) current smokers) who had baseline serum IgA measured using the Myriad RBM biomarker discovery platform. Exacerbation data was collected prospectively (mean 944.3 (SD 281.3) days), and adjusted linear, logistic and zero-inflated negative binomial regressions were performed. Results Mean IgA was 269.1 mg/dL (SD 150.9). One individual had deficient levels of serum IgA (<7 mg/dL) and 25 (2.4%) had IgA level ≤70 mg/dL. Participants with IgA ≤70 mg/dL were younger (62 vs. 66 years, p = 0.01) but otherwise similar to those with higher IgA. In adjusted models, IgA ≤70 mg/dL was associated with higher exacerbation incidence rates (IRR 1.71, 95% CI 1.01–2.87, p = 0.044) and greater risk for any severe exacerbation (OR 2.99, 95% CI 1.30–6.94, p = 0.010). In adjusted models among those in the lowest decile (<120 mg/dL), each 10 mg/dL decrement in IgA (analyzed continuously) was associated with more exacerbations during follow-up (β 0.24, 95% CI 0.017–0.46, p = 0.035). Conclusions Subnormal serum IgA levels were associated with increased risk for acute exacerbations, supporting mildly impaired IgA levels as a contributing factor in COPD morbidity. Additionally, a dose-response relationship between lower serum IgA and number of exacerbations was found among individuals with serum IgA in the lowest decile, further supporting the link between serum IgA and exacerbation risk. Future COPD studies should more comprehensively characterize immune status to define the clinical relevance of these findings and their potential for therapeutic correction

  7. Plasma Gelsolin Induced Glomerular Fibrosis via the TGF-β1/Smads Signal Transduction Pathway in IgA Nephropathy

    PubMed Central

    Zhang, Lei; Han, Changsong; Ye, Fei; He, Yan; Jin, Yinji; Wang, Tianzhen; Wu, Yiqi; Jiang, Yang; Zhang, Fengmin; Jin, Xiaoming

    2017-01-01

    Glomerular fibrosis has been shown to be closely related to the progression and prognosis of IgA nephropathy (IgAN). However, mechanism underlying IgAN glomerular fibrosis remains unclear. Recently, our study showed that plasma gelsolin (pGSN) was decreased in the serum of an IgAN mouse model and that pGSN deposition was found in the glomeruli. Another cytokine, TGF-β1, which is closely related to glomerular fibrosis, was also found to be highly expressed in the glomeruli. In the present study, we report that pGSN induces glomerular fibrosis through the TGF-β1/Smads signal transduction pathway. This is supported by the following findings: human mesangial cells (HMCs) show remarkable morphological changes and proliferation in response to co-stimulation with pGSN and polymeric IgA1 (pIgA1) from IgAN patients compared to other controls. Moreover, ELISA assays showed that more TGF-β1 secretion was found in HMCs supernatants in the co-stimulation group. Further experiments showed increased TGF-β1, Smad3, p-Smad2/3, Smad4, and collagen 1 and decreased Smad7 expression in the co-stimulation group. Our present study implied that the synergistic effect of pGSN and pIgA induced glomerular fibrosis via the TGF-β1/Smads signal transduction pathway. This might be a potential mechanism for the glomerular fibrosis observed in IgAN patients. PMID:28208683

  8. Anti-apoptotic Role of Caspase-cleaved GAB1 Adaptor Protein in Hepatocyte Growth Factor/Scatter Factor-MET Receptor Protein Signaling*

    PubMed Central

    Le Goff, Arnaud; Ji, Zongling; Leclercq, Bérénice; Bourette, Roland P.; Mougel, Alexandra; Guerardel, Cateline; de Launoit, Yvan; Vicogne, Jérôme; Goormachtigh, Gautier; Fafeur, Véronique

    2012-01-01

    The GRB2-associated binder 1 (GAB1) docking/scaffold protein is a key mediator of the MET-tyrosine kinase receptor activated by hepatocyte growth factor/scatter factor (HGF/SF). Activated MET promotes recruitment and tyrosine phosphorylation of GAB1, which in turn recruits multiple proteins and mediates MET signaling leading to cell survival, motility, and morphogenesis. We previously reported that, without its ligand, MET is a functional caspase target during apoptosis, allowing the generation of a p40-MET fragment that amplifies apoptosis. In this study we established that GAB1 is also a functional caspase target by evidencing a caspase-cleaved p35-GAB1 fragment that contains the MET binding domain. GAB1 is cleaved by caspases before MET, and the resulting p35-GAB1 fragment is phosphorylated by MET upon HGF/SF binding and can interact with a subset of GAB1 partners, PI3K, and GRB2 but not with SHP2. This p35-GAB1 fragment favors cell survival by maintaining HGF/SF-induced MET activation of AKT and by hindering p40-MET pro-apoptotic function. These data demonstrate an anti-apoptotic role of caspase-cleaved GAB1 in HGF/SF-MET signaling. PMID:22915589

  9. Rapamycin ameliorates IgA nephropathy via cell cycle-dependent mechanisms

    PubMed Central

    Tian, Jihua; Wang, Yanhong; Liu, Xinyan; Zhou, Xiaoshuang

    2014-01-01

    IgA nephropathy is the most frequent type of glomerulonephritis worldwide. The role of cell cycle regulation in the pathogenesis of IgA nephropathy has been studied. The present study was designed to explore whether rapamycin ameliorates IgA nephropathy via cell cycle-dependent mechanisms. After establishing an IgA nephropathy model, rats were randomly divided into four groups. Coomassie Brilliant Blue was used to measure the 24-h urinary protein levels. Renal function was determined using an autoanalyzer. Proliferation was assayed via Proliferating Cell Nuclear Antigen (PCNA) immunohistochemistry. Rat mesangial cells were cultured and divided into the six groups. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) and flow cytometry were used to detect cell proliferation and the cell cycle phase. Western blotting was performed to determine cyclin E, cyclin-dependent kinase 2, p27Kip1, p70S6K/p-p70S6K, and extracellular signal-regulated kinase 1/2/p- extracellular signal-regulated kinase 1/2 protein expression. A low dose of the mammalian target of rapamycin (mTOR) inhibitor rapamycin prevented an additional increase in proteinuria, protected kidney function, and reduced IgA deposition in a model of IgA nephropathy. Rapamycin inhibited mesangial cell proliferation and arrested the cell cycle in the G1 phase. Rapamycin did not affect the expression of cyclin E and cyclin-dependent kinase 2. However, rapamycin upregulated p27Kip1 at least in part via AKT (also known as protein kinase B)/mTOR. In conclusion, rapamycin can affect cell cycle regulation to inhibit mesangial cell proliferation, thereby reduce IgA deposition, and slow the progression of IgAN. PMID:25349217

  10. Demonstration by Mass Spectrometry that Purified Native Treponema pallidum Rare Outer Membrane Protein 1 (Tromp1) Has a Cleaved Signal Peptide

    PubMed Central

    Blanco, David R.; Whitelegge, Julian P.; Miller, James N.; Lovett, Michael A.

    1999-01-01

    Purified native Tromp1 was subjected to mass spectrometric analysis in order to determine conclusively whether this protein possesses a cleaved or uncleaved signal peptide. The molecular masses of Tromp1, three Treponema pallidum lipoproteins, and a bovine serum albumin (BSA) control were determined by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. The molecular masses of all of the T. pallidum lipoproteins and BSA were within 0.7% of their respective calculated masses. The molecular mass of Tromp1 was 31,510 Da, which is consistent with a signal-less form of Tromp1, given a calculated mass of unprocessed Tromp1 of 33,571 Da, a difference of 2,061 Da (a 6.5% difference). Purified native Tromp1 was also subjected to MALDI-TOF analysis in comparison to recombinant Tromp1 following cyanogen bromide cleavage, which further confirmed the identity of Tromp1 and showed that native Tromp1 was not degraded at the carboxy terminus. These studies confirm that Tromp1 is processed and does not contain an uncleaved signal peptide as previously reported. PMID:10438785

  11. Spontaneous remission of IgA nephropathy associated with resolution of hepatitis A.

    PubMed

    Han, Seung Hyeok; Kang, Ea Wha; Kie, Jeong Hae; Yoo, Tae Hyun; Choi, Kyu Hun; Han, Dae-Suk; Kang, Shin-Wook

    2010-12-01

    Although most cases of immunoglobulin A (IgA) nephropathy are idiopathic, several diseases are associated with IgA nephropathy. Of these, chronic liver disease resulting from hepatitis B or C virus infection has been reported as a secondary cause of IgA nephropathy. Recently, hepatitis A virus (HAV)-associated kidney disease has received attention because acute kidney injury can occur as a complication of HAV infection, generally caused by acute tubular necrosis or interstitial nephritis. However, unlike IgA nephropathy related to hepatitis B or C, HAV-associated IgA nephropathy is extremely rare and long-term outcomes have not been reported yet. We describe a case of spontaneous remission of IgA nephropathy associated with serologically documented HAV infection. The patient presented with microhematuria and moderate proteinuria, but acute kidney injury did not occur during active hepatic injury. Kidney biopsy specimens clearly showed mesangial IgA deposits with intact tubules and interstitium. Serum liver enzyme levels returned to reference values 1 month after the onset of acute hepatitis, but urinary protein excretion remained increased. Approximately 1 year later, urinary abnormalities were resolved and a second biopsy showed no mesangial IgA deposits. These findings suggest that IgA nephropathy can transiently accompany HAV infection, but may not progress to chronic glomerulonephritis after recovery from HAV. Copyright © 2010 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  12. Enhancement of intestinal IgA production by Ajoene in mice.

    PubMed

    Washiya, Yuki; Nishikawa, Tomoaki; Fujino, Tsuchiyoshi

    2013-01-01

    We investigated the effects of ajoene on intestinal IgA production. Ajoene (1.35, 4.5, and 13.5 µg/kg/d) was administered to mice for 4 weeks. The fecal IgA level in the 13.5 µg/kg/d group increased after 3 weeks. The intestinal IgA level also increased in a dose-dependent manner upon ajoene administration. An oil-macerated garlic extract, with 1500 µg/g of ajoene, enhanced the intestinal IgA production.

  13. Rapamycin ameliorates IgA nephropathy via cell cycle-dependent mechanisms.

    PubMed

    Tian, Jihua; Wang, Yanhong; Liu, Xinyan; Zhou, Xiaoshuang; Li, Rongshan

    2015-07-01

    IgA nephropathy is the most frequent type of glomerulonephritis worldwide. The role of cell cycle regulation in the pathogenesis of IgA nephropathy has been studied. The present study was designed to explore whether rapamycin ameliorates IgA nephropathy via cell cycle-dependent mechanisms. After establishing an IgA nephropathy model, rats were randomly divided into four groups. Coomassie Brilliant Blue was used to measure the 24-h urinary protein levels. Renal function was determined using an autoanalyzer. Proliferation was assayed via Proliferating Cell Nuclear Antigen (PCNA) immunohistochemistry. Rat mesangial cells were cultured and divided into the six groups. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) and flow cytometry were used to detect cell proliferation and the cell cycle phase. Western blotting was performed to determine cyclin E, cyclin-dependent kinase 2, p27(Kip1), p70S6K/p-p70S6K, and extracellular signal-regulated kinase 1/2/p- extracellular signal-regulated kinase 1/2 protein expression. A low dose of the mammalian target of rapamycin (mTOR) inhibitor rapamycin prevented an additional increase in proteinuria, protected kidney function, and reduced IgA deposition in a model of IgA nephropathy. Rapamycin inhibited mesangial cell proliferation and arrested the cell cycle in the G1 phase. Rapamycin did not affect the expression of cyclin E and cyclin-dependent kinase 2. However, rapamycin upregulated p27(Kip1) at least in part via AKT (also known as protein kinase B)/mTOR. In conclusion, rapamycin can affect cell cycle regulation to inhibit mesangial cell proliferation, thereby reduce IgA deposition, and slow the progression of IgAN. © 2014 by the Society for Experimental Biology and Medicine.

  14. Breast milk IgA to foods has different epitope specificity than serum IgA-Evidence for entero-mammary link for food-specific IgA?

    PubMed

    Seppo, A E; Savilahti, E M; Berin, M C; Sampson, H A; Järvinen, K M

    2017-10-01

    We have previously shown that maternal cow's milk (CM) elimination results in downregulation of CM-specific IgA antibody levels in BM, but not in serum, suggesting that an entero-mammary link may exist for food-specific antibody-secreting cells. We sought to investigate whether food-specific IgA epitope profiles differ intra-individually between mother's serum and BM. We also examined how infants' food epitope-specific IgA develops in early infancy and the relationship of IgA epitope recognition with development of cow's milk allergy (CMA). We measured specific IgA to a series of overlapping peptides in major CM allergens (α s1 -, α s2 -, β- and κ-caseins and β-lactoglobulin) in paired maternal and infant serum as well as BM samples in 31 mother-infant dyads within the first 15 post-partum months utilizing peptide microarray. There was significant discordance in epitope specificity between BM and maternal sera ranging from only 13% of sample pairs sharing at least one epitope in α s1 -casein to 73% in κ-casein. Epitope-specific IgA was detectable in infants' sera starting at less than 3 months of age. Sera of mothers with a CMA infant had increased binding of epitope-specific IgA to CM proteins compared to those with a non-CMA infant. These findings support the concept that mother's milk has a distinct antifood antibody repertoire when compared to the antibody repertoire of the peripheral blood. Increased binding of serum epitope-specific IgA to CM in mothers of infants with CMA may reflect inherited systemic immunogenicity of CM proteins in these families, although specific IgA in breast milk was not proportionally up-regulated. © 2017 John Wiley & Sons Ltd.

  15. IgA Fc receptors.

    PubMed

    Monteiro, Renato C; Van De Winkel, Jan G J

    2003-01-01

    The IgA receptor family comprises a number of surface receptors including the polymeric Ig receptor involved in epithelial transport of IgA/IgM, the myeloid specific IgA Fc receptor (FcalphaRI or CD89), the Fcalpha/muR, and at least two alternative IgA receptors. These are the asialoglycoprotein receptor and the transferrin receptor, which have been implicated in IgA catabolism, and tissue IgA deposition. In this review we focus on the biology of FcalphaRI (CD89). FcalphaRI is expressed on neutrophils, eosinophils, monocytes/macrophages, dendritic cells, and Kupffer cells. This receptor represents a heterogeneously glycosylated transmembrane protein that binds both IgA subclasses with low affinity. A single gene encoding FcalphaRI has been isolated, which is located within the leukocyte receptor cluster on chromosome 19. The FcalphaRI alpha chain lacks canonical signal transduction domains but can associate with the FcR gamma-chain that bears an activation motif (ITAM) in the cytoplasmic domain, allowing activatory functions. FcalphaRI expressed alone mediates endocytosis and recyling of IgA. No FcalphaRI homologue has been defined in the mouse, and progress in defining the in vivo role of FcalphaRI has been made using human FcalphaRI transgenic (Tg) mice. FcalphaRI-Tg mice demonstrated FcalphaRI expression on Kupffer cells and so defined a key role for the receptor in mucosal defense. The receptor functions as a second line of antibacterial defense involving serum IgA rather than secretory IgA. Studies in FcalphaRI-Tg mice, furthermore, defined an essential role for soluble FcalphaRI in the development of IgA nephropathy by formation of circulating IgA-FcalphaRI complexes. Finally, recent work points out a role for human IgA in treatment of infectious and neoplastic diseases.

  16. A Randomized, Controlled Trial of Rituximab in IgA Nephropathy with Proteinuria and Renal Dysfunction

    PubMed Central

    Lafayette, Richard A.; Canetta, Pietro A.; Rovin, Brad H.; Appel, Gerald B.; Novak, Jan; Nath, Karl A.; Sethi, Sanjeev; Tumlin, James A.; Mehta, Kshama; Hogan, Marie; Erickson, Stephen; Julian, Bruce A.; Leung, Nelson; Enders, Felicity T.; Brown, Rhubell; Knoppova, Barbora; Hall, Stacy

    2017-01-01

    IgA nephropathy frequently leads to progressive CKD. Although interest surrounds use of immunosuppressive agents added to standard therapy, several recent studies have questioned efficacy of these agents. Depleting antibody–producing B cells potentially offers a new therapy. In this open label, multicenter study conducted over 1-year follow-up, we randomized 34 adult patients with biopsy–proven IgA nephropathy and proteinuria >1 g/d, maintained on angiotensin–converting enzyme inhibitors or angiotensin receptor blockers with well controlled BP and eGFR<90 ml/min per 1.73 m2, to receive standard therapy or rituximab with standard therapy. Primary outcome measures included change in proteinuria and change in eGFR. Median baseline serum creatinine level (range) was 1.4 (0.8–2.4) mg/dl, and proteinuria was 2.1 (0.6–5.3) g/d. Treatment with rituximab depleted B cells and was well tolerated. eGFR did not change in either group. Rituximab did not alter the level of proteinuria compared with that at baseline or in the control group; three patients in each group had ≥50% reduction in level of proteinuria. Serum levels of galactose-deficient IgA1 or antibodies against galactose-deficient IgA1 did not change. In this trial, rituximab therapy did not significantly improve renal function or proteinuria assessed over 1 year. Although rituximab effectively depleted B cells, it failed to reduce serum levels of galactose-deficient IgA1 and antigalactose–deficient IgA1 antibodies. Lack of efficacy of rituximab, at least at this stage and severity of IgA nephropathy, may reflect a failure of rituximab to reduce levels of specific antibodies assigned salient pathogenetic roles in IgA nephropathy. PMID:27821627

  17. A Randomized, Controlled Trial of Rituximab in IgA Nephropathy with Proteinuria and Renal Dysfunction.

    PubMed

    Lafayette, Richard A; Canetta, Pietro A; Rovin, Brad H; Appel, Gerald B; Novak, Jan; Nath, Karl A; Sethi, Sanjeev; Tumlin, James A; Mehta, Kshama; Hogan, Marie; Erickson, Stephen; Julian, Bruce A; Leung, Nelson; Enders, Felicity T; Brown, Rhubell; Knoppova, Barbora; Hall, Stacy; Fervenza, Fernando C

    2017-04-01

    IgA nephropathy frequently leads to progressive CKD. Although interest surrounds use of immunosuppressive agents added to standard therapy, several recent studies have questioned efficacy of these agents. Depleting antibody-producing B cells potentially offers a new therapy. In this open label, multicenter study conducted over 1-year follow-up, we randomized 34 adult patients with biopsy-proven IgA nephropathy and proteinuria >1 g/d, maintained on angiotensin-converting enzyme inhibitors or angiotensin receptor blockers with well controlled BP and eGFR<90 ml/min per 1.73 m 2 , to receive standard therapy or rituximab with standard therapy. Primary outcome measures included change in proteinuria and change in eGFR. Median baseline serum creatinine level (range) was 1.4 (0.8-2.4) mg/dl, and proteinuria was 2.1 (0.6-5.3) g/d. Treatment with rituximab depleted B cells and was well tolerated. eGFR did not change in either group. Rituximab did not alter the level of proteinuria compared with that at baseline or in the control group; three patients in each group had ≥50% reduction in level of proteinuria. Serum levels of galactose-deficient IgA1 or antibodies against galactose-deficient IgA1 did not change. In this trial, rituximab therapy did not significantly improve renal function or proteinuria assessed over 1 year. Although rituximab effectively depleted B cells, it failed to reduce serum levels of galactose-deficient IgA1 and antigalactose-deficient IgA1 antibodies. Lack of efficacy of rituximab, at least at this stage and severity of IgA nephropathy, may reflect a failure of rituximab to reduce levels of specific antibodies assigned salient pathogenetic roles in IgA nephropathy. Copyright © 2017 by the American Society of Nephrology.

  18. Biomarkers of IgA vasculitis nephritis in children

    PubMed Central

    Pillebout, Evangeline; Jamin, Agnès; Ayari, Hamza; Housset, Pierre; Pierre, Melissa; Sauvaget, Virginia; Viglietti, Denis; Deschenes, Georges

    2017-01-01

    Henoch–Schönlein purpura is a systemic vasculitis characterized by IgA deposits, which target the skin, joints, and kidneys, among other organs. In children, prognosis is often good but little is known about biomarkers of pediatric nephritis. We hypothesized that biological markers, including cytokines, immunoglobulins, IgA-immune complexes, IgA glycosylation and neutrophil gelatinase-associated lipocalin (NGAL), may discriminate IgA vasculitis (IgAV) pediatric patients with renal involvement from those without renal involvement. Fifty children at the time of IgAV rash between 2010 and 2015 were prospectively enrolled and compared to 21 controls. All patients were assessed for clinical and biological parameters at the time of diagnosis, including the levels of cytokines, immunoglobulins, immune complexes, IgA glycosylation and NGAL in serum and urine. Among IgAV patients, 33 patients exhibited nephritis (IgAV-N) and 17 children were without nephritis (IgAV-woN). The serum level of galactose-deficient (Gd)-IgA1 (p<0.01) and the urinary concentrations of IgA, IgG, IgM, IL-6, IL-8, IL-10, IgA-IgG complexes and IgA-sCD89 complexes (p<0.001 for all) were higher in the IgAV-N patients than in the IgAV-woN patients. Among those markers, urinary IgA and IgM had the highest AUC (0.86 and 0.87 respectively, p<0.0001). This prospective cohort study furthers our understanding of the pathophysiology of IgAV. We identified biomarkers that are able to distinguish patients initially with or without nephritis. To conclude, serum Gd-IgA1 and urinary IgA, IgG, IgM, IL-6, IL-8, IL-10, and IgA-IgG and IgA-sCD89 complexes could identify IgAV pediatric patients with renal involvement at the time of diagnosis. PMID:29190714

  19. Discovery of the 3-Imino-1,2,4-thiadiazinane 1,1-Dioxide Derivative Verubecestat (MK-8931)–A β-Site Amyloid Precursor Protein Cleaving Enzyme 1 Inhibitor for the Treatment of Alzheimer’s Disease

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, Jack D.; Li, Sarah W.; Brunskill, Andrew P. J.

    Verubecestat 3 (MK-8931), a diaryl amide-substituted 3-imino-1,2,4-thiadiazinane 1,1-dioxide derivative, is a high-affinity β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitor currently undergoing Phase 3 clinical evaluation for the treatment of mild to moderate and prodromal Alzheimer’s disease. Although not selective over the closely related aspartyl protease BACE2, verubecestat has high selectivity for BACE1 over other key aspartyl proteases, notably cathepsin D, and profoundly lowers CSF and brain Aβ levels in rats and nonhuman primates and CSF Aβ levels in humans. In this annotation, we describe the discovery of 3, including design, validation, and selected SAR around the novel iminothiadiazinanemore » dioxide core as well as aspects of its preclinical and Phase 1 clinical characterization.« less

  20. The cleaved FAS ligand activates the Na(+)/H(+) exchanger NHE1 through Akt/ROCK1 to stimulate cell motility.

    PubMed

    Monet, Michael; Poët, Mallorie; Tauzin, Sébastien; Fouqué, Amélie; Cophignon, Auréa; Lagadic-Gossmann, Dominique; Vacher, Pierre; Legembre, Patrick; Counillon, Laurent

    2016-06-15

    Transmembrane CD95L (Fas ligand) can be cleaved to release a promigratory soluble ligand, cl-CD95L, which can contribute to chronic inflammation and cancer cell dissemination. The motility signaling pathway elicited by cl-CD95L remains poorly defined. Here, we show that in the presence of cl-CD95L, CD95 activates the Akt and RhoA signaling pathways, which together orchestrate an allosteric activation of the Na(+)/H(+) exchanger NHE1. Pharmacologic inhibition of Akt or ROCK1 independently blocks the cl-CD95L-induced migration. Confirming these pharmacologic data, disruption of the Akt and ROCK1 phosphorylation sites on NHE1 decreases cell migration in cells exposed to cl-CD95L. Together, these findings demonstrate that NHE1 is a novel molecular actor in the CD95 signaling pathway that drives the cl-CD95L-induced cell migration through both the Akt and RhoA signaling pathways.

  1. The cleaved FAS ligand activates the Na+/H+ exchanger NHE1 through Akt/ROCK1 to stimulate cell motility

    PubMed Central

    Monet, Michael; Poët, Mallorie; Tauzin, Sébastien; Fouqué, Amélie; Cophignon, Auréa; Lagadic-Gossmann, Dominique; Vacher, Pierre; Legembre, Patrick; Counillon, Laurent

    2016-01-01

    Transmembrane CD95L (Fas ligand) can be cleaved to release a promigratory soluble ligand, cl-CD95L, which can contribute to chronic inflammation and cancer cell dissemination. The motility signaling pathway elicited by cl-CD95L remains poorly defined. Here, we show that in the presence of cl-CD95L, CD95 activates the Akt and RhoA signaling pathways, which together orchestrate an allosteric activation of the Na+/H+ exchanger NHE1. Pharmacologic inhibition of Akt or ROCK1 independently blocks the cl-CD95L-induced migration. Confirming these pharmacologic data, disruption of the Akt and ROCK1 phosphorylation sites on NHE1 decreases cell migration in cells exposed to cl-CD95L. Together, these findings demonstrate that NHE1 is a novel molecular actor in the CD95 signaling pathway that drives the cl-CD95L-induced cell migration through both the Akt and RhoA signaling pathways. PMID:27302366

  2. Kid cleaves specific mRNAs at UUACU sites to rescue the copy number of plasmid R1

    PubMed Central

    Pimentel, Belén; Madine, Mark A; de la Cueva-Méndez, Guillermo

    2005-01-01

    Stability and copy number of extra-chromosomal elements are tightly regulated in prokaryotes and eukaryotes. Toxin Kid and antitoxin Kis are the components of the parD stability system of prokaryotic plasmid R1 and they can also function in eukaryotes. In bacteria, Kid was thought to become active only in cells that lose plasmid R1 and to cleave exclusively host mRNAs at UA(A/C/U) trinucleotide sites to eliminate plasmid-free cells. Instead, we demonstrate here that Kid becomes active in plasmid-containing cells when plasmid copy number decreases, cleaving not only host- but also a specific plasmid-encoded mRNA at the longer and more specific target sequence UUACU. This specific cleavage by Kid inhibits bacterial growth and, at the same time, helps to restore the plasmid copy number. Kid targets a plasmid RNA that encodes a repressor of the synthesis of an R1 replication protein, resulting in increased plasmid DNA replication. This mechanism resembles that employed by some human herpesviruses to regulate viral amplification during infection. PMID:16163387

  3. The paracaspase MALT1 cleaves HOIL1 reducing linear ubiquitination by LUBAC to dampen lymphocyte NF-κB signalling

    PubMed Central

    Klein, Theo; Fung, Shan-Yu; Renner, Florian; Blank, Michael A.; Dufour, Antoine; Kang, Sohyeong; Bolger-Munro, Madison; Scurll, Joshua M.; Priatel, John J.; Schweigler, Patrick; Melkko, Samu; Gold, Michael R.; Viner, Rosa I.; Régnier, Catherine H.; Turvey, Stuart E.; Overall, Christopher M.

    2015-01-01

    Antigen receptor signalling activates the canonical NF-κB pathway via the CARD11/BCL10/MALT1 (CBM) signalosome involving key, yet ill-defined roles for linear ubiquitination. The paracaspase MALT1 cleaves and removes negative checkpoint proteins, amplifying lymphocyte responses in NF-κB activation and in B-cell lymphoma subtypes. To identify new human MALT1 substrates, we compare B cells from the only known living MALT1mut/mut patient with healthy MALT1+/mut family members using 10-plex Tandem Mass Tag TAILS N-terminal peptide proteomics. We identify HOIL1 of the linear ubiquitin chain assembly complex as a novel MALT1 substrate. We show linear ubiquitination at B-cell receptor microclusters and signalosomes. Late in the NF-κB activation cycle HOIL1 cleavage transiently reduces linear ubiquitination, including of NEMO and RIP1, dampening NF-κB activation and preventing reactivation. By regulating linear ubiquitination, MALT1 is both a positive and negative pleiotropic regulator of the human canonical NF-κB pathway—first promoting activation via the CBM—then triggering HOIL1-dependent negative-feedback termination, preventing reactivation. PMID:26525107

  4. Human milk IgA concentrations during the first year of lactation

    PubMed Central

    Weaver, L.; Arthur, H.; Bunn, J.; Thomas, J.

    1998-01-01

    AIMS—To measure the concentrations of total IgA in the milk secreted by both breasts, throughout the first year of lactation, in a cohort of Gambian mothers of infants at high risk of infection.
SUBJECTS AND METHODS—Sixty five women and their infants were studied monthly from the 4th to 52nd postpartum week. Samples of milk were obtained from each breast by manual expression immediately before the infant was suckled. Milk intakes were measured by test weighing the infants before and after feeds over 12 hour periods; IgA concentrations were determined by enzyme linked immunosorbent assay.
RESULTS—A total of 1590 milk samples was measured. The median (interquartile range) concentration of IgA for all samples was 0.708(0.422-1.105) g/l; that in milk obtained from the left breast was 0.785 (0.458-1.247) g/l, and that in milk obtained from the right breast was 0.645 (0.388-1.011) g/l (p < 0.0001). There was no significant change in milk or IgA intakes with advancing infant age, but there was a close concordance of IgA concentrations between the two breasts, with "tracking" of the output of the left and right breasts. There was a significant (p < 0.01) negative correlation between maternal age and parity, and weight of milk ingested by infants. During the dry season (December to May) the median (interquartile range) IgA concentration was significantly higher at 0.853 (0.571-1.254) g/l than during the rainy season (June to November), when it was 0.518 (0.311-0.909) g/l (p < 0.0001).
CONCLUSIONS—Sustained IgA secretion is likely to protect suckling infants from microbial infection.

 PMID:9613353

  5. IgA deficiency in wolves.

    PubMed

    Frankowiack, Marcel; Hellman, Lars; Zhao, Yaofeng; Arnemo, Jon M; Lin, Miaoli; Tengvall, Katarina; Møller, Torsten; Lindblad-Toh, Kerstin; Hammarström, Lennart

    2013-06-01

    Low mean concentrations of serum immunoglobulin A (IgA) and an increased frequency of overt IgA deficiency (IgAD) in certain dog breeds raises the question whether it is a breeding-enriched phenomenon or a legacy from the dog's ancestor, the gray wolf (Canis lupus). The IgA concentration in 99 serum samples from 58 free-ranging and 13 captive Scandinavian wolves, was therefore measured by capture ELISA. The concentrations were markedly lower in the wolf serum samples than in the dog controls. Potential differences in the IgA molecule between dogs and wolves were addressed by sequencing the wolf IgA heavy chain constant region encoding gene (IGHA). Complete amino acid sequence homology was found. Detection of wolf and dog IgA was ascertained by showing identity using double immunodiffusion. We suggest that the vast majority of wolves, the ancestor of the dog, are IgA deficient. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. The role of the carbohydrate chains in complement (C3) fixation by solid-phase-bound human IgA.

    PubMed Central

    Nikolova, E B; Tomana, M; Russell, M W

    1994-01-01

    In contrast to antigen-antibody complexes containing native human IgA, solid-phase-deposited IgA activates the alternative complement pathway and binds C3b. To investigate the role of carbohydrate chains in this, various human IgA preparations were treated with neuraminidase alone or together with N-glycanase or O-glycanase, or with mixed glycosidases from the oral bacterium, Streptococcus mitis. Depletion of oligosaccharides was determined by carbohydrate analysis. Removal of sialic acid and N-linked glycan chains greatly increased the C3b-fixing properties of normal serum IgA1 and IgA2. Myeloma IgA1 and IgA2 proteins and secretory IgA had higher C3b-binding activity than normal serum IgA, and this was further increased by removal of sialic acid and N-linked glycans. Fc alpha and Fc alpha-SC fragments of myeloma and secretory IgA1, respectively, but not Fab alpha fragments, obtained by cleavage with bacterial IgA1 proteases and also free secretory component, fixed C3b by the alternative pathway. Images Figure 4 PMID:7927504

  7. Low pretransplant IgA level is associated with early post-lung transplant seromucous infection.

    PubMed

    Murthy, Sudish C; Avery, Robin K; Budev, Marie; Gupta, Sandeep; Pettersson, Gösta B; Nowicki, Edward R; Mehta, Atul; Chapman, Jeffrey T; Rajeswaran, Jeevanantham; Blackstone, Eugene H

    2018-04-13

    Infection is an important cause of morbidity and mortality after lung transplantation. Immunoglobulins are part of both seromucous (IgA) and serum (IgG) infection defense mechanisms. We therefore hypothesized that lower pretransplant IgA levels would be associated with more early post-lung transplant seromucous infections and greater mortality independent of IgG. From January 2000 to July 2010, 538 patients undergoing primary lung transplantation had pretransplant IgA (n = 429) and IgG (n = 488) measured as a clinical routine. Median IgA was 200 mg·dL -1 (2% < 70 mg·dL -1 , lower limit of normal); median IgG was 970 mg·dL -1 (5% < 600 mg·dL -1 ). Intensive microbiology review was used to categorize infections and their causative organisms within the first posttransplant year. In total, 397 seromucous infections were observed in 247 patients, most bacterial. Although IgA and IgG were moderately correlated (r = 0.5, P < .0001), low pretransplant IgA was a strong risk factor (P = .01) for seromucous infections, but pretransplant IgG was not (P ≥ .6). As pretransplant IgA levels fell below 200 mg·dL -1 , the risk of these posttransplant infections rose nearly linearly. Lower pretransplant levels of IgA were associated with greater posttransplant mortality to end of follow-up (P = .004), but pretransplant IgG was not (P ≥ .3). Low levels of preoperative IgA, an important immunoglobulin involved in mucosal immunologic defense, but not IgG, are associated with seromucous infections in the year after lung transplantation and increased follow-up mortality. It would appear prudent to identify patients with relative IgA deficiency at listing and to increase vigilance of monitoring for, and prophylaxis against, seromucous infection in this high-risk population. Copyright © 2018. Published by Elsevier Inc.

  8. Do we need to measure total serum IgA to exclude IgA deficiency in coeliac disease?

    PubMed Central

    Sinclair, D; Saas, M; Turk, A; Goble, M; Kerr, D

    2006-01-01

    Background Screening for IgA deficiency in patients with coeliac disease is essential because of the increased incidence of IgA deficiency associated with the disease, which usually relies on the estimation of IgA levels in each case. Aim To devise a method of excluding IgA deficiency without measuring total serum IgA in each case. Materials and methods The optical density readings on enzyme‐linked immunosorbent assay (ELISA) of 608 routine samples received for tissue transglutaminase (TTG) antibody testing for coeliac disease were compared with their total IgA concentrations. Dilution experiments were also carried out to ensure linear relationships between optical density on ELISA and IgA concentrations and to compare the sensitivities for TTG and endomysium antibodies in TTG‐positive samples. Results and discussion A clear relationship was shown between total IgA concentration and TTG optical density readings by ELISA. To ensure a positive TTG result if antibodies are present, it was possible to recommend an optical density level above which all samples have sufficient IgA. Samples with optical density <0.05 should be investigated further by estimating total IgA and, if low, samples should be subjected to immunofluorescence microscopy testing for IgA and IgG endomysium antibodies. Conclusions An easier, more cost‐effective and practical way of excluding IgA deficiency in the investigation on coeliac disease is reported. PMID:16489174

  9. HIV-1 evades virus-specific IgG2 and IgA class switching by targeting systemic and intestinal B cells via long-range intercellular conduits

    PubMed Central

    Xu, Weifeng; Santini, Paul A.; Sullivan, John S.; He, Bing; Shan, Meimei; Ball, Susan C.; Dyer, Wayne B.; Ketas, Thomas J.; Chadburn, Amy; Cohen-Gould, Leona; Knowles, Daniel M.; Chiu, April; Sanders, Rogier W.; Chen, Kang; Cerutti, Andrea

    2009-01-01

    Contact-dependent communication between immune cells generates protection, but also facilitates viral spread. We found that macrophages formed long-range actin-propelled conduits in response to negative factor (Nef), a human immunodeficiency virus type-1 (HIV-1) protein with immunosuppressive functions. Conduits attenuated immunoglobulin G2 (IgG2) and IgA class switching in systemic and intestinal lymphoid follicles by shuttling Nef from infected macrophages to B cells through a guanine exchange factor-dependent pathway involving the amino-terminal anchor, central core and carboxy-terminal flexible loop of Nef. By showing stronger virus-specific IgG2 and IgA responses in patients harboring Nef-deficient virions, our data suggest that HIV-1 exploits intercellular highways as a “Trojan horse” to deliver Nef to B cells and evade humoral immunity systemically and at mucosal sites of entry. PMID:19648924

  10. T cell cytokine polarity as a determinant of immunoglobulin A (IgA) glycosylation and the severity of experimental IgA nephropathy.

    PubMed

    Chintalacharuvu, S R; Yamashita, M; Bagheri, N; Blanchard, T G; Nedrud, J G; Lamm, M E; Tomino, Y; Emancipator, S N

    2008-09-01

    Immunoglobulin A (IgA) glycosylation, recognized as an important pathogenic factor in IgA nephropathy (IgAN), is apparently controlled by the polarity of T helper (Th) cytokine responses. To examine the role of cytokine polarity in IgAN, inbred mice were immunized by intraperitoneal priming with inactivated Sendai virus (SeV) emulsified in either complete Freund's adjuvant (CFA) or incomplete Freund's adjuvant (IFA), which promote Th1- or Th2-immune response, respectively, and then boosted identically twice orally with aqueous suspensions of inactivated virus. Next, some mice were challenged intranasally with infectious SeV. Mice primed with CFA or IFA had equal reductions in nasal viral titre relative to non-immune controls, and equally increased serum levels of SeV-specific IgA antibody. Mice primed with CFA showed higher SeV-specific IgG than those with IFA. Splenocytes from mice primed with IFA produced copious amounts of interleukin (IL)-4 and IL-5, but little interferon-gamma and IL-2; those primed with CFA had reciprocal cytokine recall responses. Total serum IgA and especially SeV-specific IgA from mice primed with IFA showed a selective defect in sialylation and galactosylation. Although the frequency and intensity of glomerular deposits and haematuria did not differ, glomerulonephritis in mice primed with IFA and challenged with infectious virus was more severe than in those given CFA, as judged by serum creatinine level. We conclude that the polarity of T cell cytokines controls the pattern of IgA glycosylation and exerts direct or indirect effects on functional glomerular responses to immune complex deposition.

  11. [Progress in understanding the pathogenesis of IgA nephropathy: new perspectives for the near future?].

    PubMed

    Segarra, A

    2010-01-01

    Progress in understanding the pathogenesis of IgA nephropathy has shown that probably there is no a single IgA nephropathy with the same pathogenic mechanism, clinical course and response to therapy. The evidence currently available suggests the existence of at least two possible mechanisms of IgA deposition in the renal mesangium. In a small percentage of patients, mesangial deposition of IgA1 colocalizes with secretory component, indicating that the deposited IgA1 in glomeruli originates completely or partly in the mucose-associated lymphoid tissue. This deposition pattern has been associated with activation of complement by the lectin pathway and has been associated with a worse prognosis, although this last statement needs to be confirmed in long-term studies. The mechanisms responsible for secretory IgA deposition are not known. In the majority of patients with IgA nephropathy secretory component is not detectable in the mesangium. In these cases, the presence of elevated circulating levels of galactose-deficient IgA, produced by bone marrow plasma cells would be a predisposing factor but not sufficient to induce nephropathy. To produce kidney disease, galactose-deficient IgA1 must be deposited in the renal mesangium, and once there, either by interaction with specific receptors (CD71?), by direct activation of complement or by being the target of an IgG autoimmune response anti-IgA, induce activation, proliferation and increased mesangial matrix synthesis and eventually cell injury. In parallel, galactose-deficient IgA, through interaction with the RR Fc alpha/gamma, may activate circulating lymphocytes and monocytes and enhance their response to chemoattractants produced by the mesangial cell, causing, thus, the inflammatory infiltrate to initiate and maintain the interstitial injury. In the next few years, advances recently added to the knowledge of the pathogenesis of nephropathy IgA1 could provide new variables that allow walking in the direction of

  12. Immunocytochemical localization of the ovine immunoglobulins IgA, IgG1, IgG1A and IgG2: effect of gastro-intestinal parasitism in the sheep

    PubMed Central

    Curtain, C. C.; Anderson, N.

    1971-01-01

    A study has been made of the immunocytochemical localization of IgG1, IgG2, IgG1A and IgA in the alimentary tract and associated lymph nodes of parasitized and parasite-free sheep. No immunoglobulin-containing cells were found in the abomasal mucosa of the parasite-free sheep. On the other hand, large numbers of IgG1 and IgG1A-containing cells were found in the lamina propria and at the base of the villi of the abomasum of the parasitized sheep. IgG1, IgG1A, and IgA-containing cells were found in mucosal sections from the jejunum and ileum of both parasitized and parasite-free sheep, the number of IgG1A-containing cells being sifnificantly greater in the former than in the latter. This increase was considered to be of some importance since the IgG1A subclass appears to be involved in the allergic response of the sheep to intestinal parasites. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5FIG. 6FIG. 7 PMID:4924939

  13. Selective IgA Deficiency

    MedlinePlus

    ... immunoglobulins. Videos: Choosing Wisely » Selective IgA Deficiency Treatment & Management The underlying cause for Selective IgA Deficiency is ... the Evidence » Practice Parameter for the Diagnosis and Management of Primary Immunodefiency » 2017 Non-CME Recordings » Vaccination ...

  14. A systematic review of anti-rotavirus serum IgA antibody titer as a potential correlate of rotavirus vaccine efficacy.

    PubMed

    Patel, Manish; Glass, Roger I; Jiang, Baoming; Santosham, Mathuram; Lopman, Ben; Parashar, Umesh

    2013-07-15

    Identifying an immunological correlate of protection for rotavirus vaccines (Rotarix [RV1] and RotaTeq [RV5]) would substantially facilitate testing of interventions for improving efficacy in developing countries and evaluating additional candidate rotavirus vaccines. We accessed PubMed and ClinicalTrials.gov to identify immunogenicity and efficacy trials for RV1 and RV5 to correlate anti-rotavirus serum immunoglobulin A (IgA) antibody titers vs efficacy in regions stratified by all-cause under-5 mortality rates (u5MR). We established a cutoff point for IgA geometric mean concentration or titer (GMC) that predicted lower efficacy and calculated pooled vaccine efficacy among countries with high vs low IgA titers. We observed an inverse correlation between u5MR and IgA titers for RV1 (r(2) = 0.72; P < .001 and RV5 (r(2) = 0.66; P < .001) and between efficacy and IgA titers for both vaccines (r(2) = 0.56; P = .005). Postimmunization anti-rotavirus IgA GMC <90 were associated with decline in vaccine efficacy. Efficacy during first 2 years of life was significantly lower among countries with IgA GMC < 90 (44%; 95% confidence interval [CI], 30-55) compared to countries with GMC > 90 (85%; 95% CI, 82-88). We observed a significant correlation between IgA titers and rotavirus vaccine efficacy and hypothesize that a critical level of IgA antibody titer is associated with a sufficient level of sustained protection after rotavirus vaccination.

  15. Cytokine, chemokine and secretory IgA levels in human milk in relation to atopic disease and IgA production in infants.

    PubMed

    Böttcher, Malin F; Jenmalm, Maria C; Björkstén, Bengt

    2003-02-01

    The relationship between breast-feeding, IgA production and development of atopic disease in children is a matter of controversy. Some of this controversy might be due to individual differences in the composition of breast milk. The aim of this study was to relate the levels of cytokines, chemokines and secretory (S)-IgA antibodies in breast milk to the development of atopic manifestation and salivary IgA production in infants. Cytokine, chemokine and SIgA levels, as measured with enzyme-linked immunosorbent assay (ELISA), in colostrum and mature milk were analyzed in relation to the development of positive skin-prick tests (SPT), allergic symptoms and salivary IgA antibody production during the first 2 years of life in 53 infants. There was no association between levels of IL-4, -5, -6, -8, -10, -13, -16, IFN-gamma, TGF-beta1, -beta2, RANTES, eotaxin or SIgA levels in the breast milk with either SPT-positivity, development of allergic symptoms or salivary IgA levels during the first 2 years of life in the infants. Thus, differences in the composition of cytokines, chemokines and SIgA in breast milk did not, to any major degree, affect the development of a positive SPT, atopic symptoms, nor salivary IgA antibody production during the first 2 years of life.

  16. Glomerular diseases: emerging tests and therapies for IgA nephropathy.

    PubMed

    Canetta, Pietro A; Kiryluk, Krzysztof; Appel, Gerald B

    2014-03-01

    The last decade has seen major progress in understanding the pathogenesis as well as the prognosis and treatment of patients with IgA nephropathy (IgAN). Although the diagnostic criterion of a kidney biopsy demonstrating dominant or codominant IgA deposition remains unchanged, much more is known about the genetic and environmental factors predisposing to disease development and progression. These advances have led to the identification of novel diagnostic and prognostic markers. Among the most promising clinically are genetic profiling, quantification of galactose-deficient IgA1 levels, and measurement of anti-IgA1 immunoglobulins. While targeted treatment for IgAN remains elusive, there is mounting evidence for therapeutic interventions that alter the disease course. The appropriate validation and integration of these discoveries into clinical care represent a major challenge, but one that holds tremendous promise for refining prognostication, guiding therapy, and improving the lives of patients with IgAN.

  17. Decreased IgA+ B cells population and IgA, IgG, IgM contents of the cecal tonsil induced by dietary high fluorine in broilers.

    PubMed

    Liu, Juan; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Wang, Hesong; Wu, Bangyuan; Deng, Yuanxin; Wang, Kangping

    2013-05-02

    Fluoride is an environmental and industrial pollutant that affects various organs in humans and animals. The cecal tonsil is an important component of the mucosal immune system and performs important and unique immune functions. In the present study, we investigated the effects of dietary high fluorine on the quantities of IgA+ B cells in the cecal tonsil by immunohistochemistry, and the immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM) contents in the cecal tonsil by ELISA. A total of 280 one-day-old avian broilers were divided into four groups and fed on a corn-soybean basal diet as control diet (fluorine 22.6 mg/kg) or the same diet supplemented with 400, 800 and 1,200 mg/kg fluorine (high fluorine groups I, II and III) in the form of sodium fluoride, respectively, throughout a 42-day experimental period. The results showed that the quantities of IgA+ B cells were lower (p < 0.05 or p < 0.01) and the IgA, IgG, and IgM contents were decreased (p < 0.05 or p < 0.01) in high fluorine groups II and III in comparison with those of control group. It was concluded that dietary fluorine, in the 800-1,200 mg/kg range, could reduce the numbers of the IgA+ B cells and immunoglobulin contents in the cecal tonsil, implying the local mucosal immune function was ultimately impacted in broilers.

  18. Decreased IgA+ B Cells Population and IgA, IgG, IgM Contents of the Cecal Tonsil Induced by Dietary High Fluorine in Broilers

    PubMed Central

    Liu, Juan; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Wang, Hesong; Wu, Bangyuan; Deng, Yuanxin; Wang, Kangping

    2013-01-01

    Fluoride is an environmental and industrial pollutant that affects various organs in humans and animals. The cecal tonsil is an important component of the mucosal immune system and performs important and unique immune functions. In the present study, we investigated the effects of dietary high fluorine on the quantities of IgA+ B cells in the cecal tonsil by immunohistochemistry, and the immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM) contents in the cecal tonsil by ELISA. A total of 280 one-day-old avian broilers were divided into four groups and fed on a corn-soybean basal diet as control diet (fluorine 22.6 mg/kg) or the same diet supplemented with 400, 800 and 1,200 mg/kg fluorine (high fluorine groups I, II and III) in the form of sodium fluoride, respectively, throughout a 42-day experimental period. The results showed that the quantities of IgA+ B cells were lower (p < 0.05 or p < 0.01) and the IgA, IgG, and IgM contents were decreased (p < 0.05 or p < 0.01) in high fluorine groups II and III in comparison with those of control group. It was concluded that dietary fluorine, in the 800–1,200 mg/kg range, could reduce the numbers of the IgA+ B cells and immunoglobulin contents in the cecal tonsil, implying the local mucosal immune function was ultimately impacted in broilers. PMID:23644827

  19. Relationship between frequency of pilocarpine administration and salivary IgA level.

    PubMed

    Smith, D J; Taubman, M A; Ebersole, J L; King, W

    1982-12-01

    The effect of repetitive administration of pilocarpine nitrate on the salivary volume and salivary IgA concentration was studied in the NIH white hamster. One and one-half to three-fold increases in salivary volume, coupled with decreases of 1/3 to 2/3 in IgA concentration, occurred as the frequency of administration of pilocarpine increased.

  20. Glomerular Diseases: Emerging Tests and Therapies for IgA Nephropathy

    PubMed Central

    Kiryluk, Krzysztof; Appel, Gerald B.

    2014-01-01

    Summary The last decade has seen major progress in understanding the pathogenesis as well as the prognosis and treatment of patients with IgA nephropathy (IgAN). Although the diagnostic criterion of a kidney biopsy demonstrating dominant or codominant IgA deposition remains unchanged, much more is known about the genetic and environmental factors predisposing to disease development and progression. These advances have led to the identification of novel diagnostic and prognostic markers. Among the most promising clinically are genetic profiling, quantification of galactose-deficient IgA1 levels, and measurement of anti-IgA1 immunoglobulins. While targeted treatment for IgAN remains elusive, there is mounting evidence for therapeutic interventions that alter the disease course. The appropriate validation and integration of these discoveries into clinical care represent a major challenge, but one that holds tremendous promise for refining prognostication, guiding therapy, and improving the lives of patients with IgAN. PMID:24071652

  1. Effects of yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 on the IgA flow rate of saliva in elderly persons residing in a nursing home: A before-after non-randomised intervention study.

    PubMed

    Yamamoto, Yuko; Fujino, Kazuhiro; Saruta, Juri; Takahashi, Toru; To, Masahiro; Fuchida, Shinya; Shimizu, Tomoko; Kamata, Yohei; Misawa, Kyoko; Tsukinoki, Keiichi

    2017-12-01

    The aim of this study was to investigate the alterations in the salivary IgA levels of elderly persons administered yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) OLL1073R-1, which has been reported to reduce the risk of colds. Salivary immunoglobulin (Ig)A plays an important role in the defence of the oral cavity mucous membrane against foreign antigens and pathogens. Accordingly, low levels of salivary IgA are associated with an increased risk of upper respiratory tract infection. Furthermore, salivary IgA secretion has been reported to decrease with age. Recently, several studies have reported that certain strains of Lactobacillus and their products can modulate the immune response, but there are currently few studies on the effects of on the IgA level in human saliva. This was a before-after non-randomised intervention study. Thirty-seven elderly persons (mean age, 82.7 years) residing in a single nursing home ingested 112 g of the yogurt every morning for 12 weeks. The participants' saliva was collected before and after 4, 8 and 12 weeks of yogurt intake. Our results showed that yogurt intake affected the concentration of IgA in the saliva (P < .0001). Additionally, yogurt intake and the body weight of the participants affected the IgA flow rate of saliva (P = .0003 and .03, respectively). Continuous intake of yogurt fermented with L. bulgaricus OLL1073R-1 may help improve the mucosal immune function in elderly people with weakened immune systems. © 2017 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  2. Comparison of the Specificities of IgG, IgG-Subclass, IgA and IgM Reactivities in African and European HIV-Infected Individuals with an HIV-1 Clade C Proteome-Based Array

    PubMed Central

    Gallerano, Daniela; Ndlovu, Portia; Makupe, Ian; Focke-Tejkl, Margarete; Fauland, Kerstin; Wollmann, Eva; Puchhammer-Stöckl, Elisabeth; Keller, Walter; Sibanda, Elopy; Valenta, Rudolf

    2015-01-01

    A comprehensive set of recombinant proteins and peptides of the proteome of HIV-1 clade C was prepared and purified and used to measure IgG, IgG-subclass, IgA and IgM responses in HIV-infected patients from Sub-Saharan Africa, where clade C is predominant. As a comparison group, HIV-infected patients from Europe were tested. African and European patients showed an almost identical antibody reactivity profile in terms of epitope specificity and involvement of IgG, IgG subclass, IgA and IgM responses. A V3-peptide of gp120 was identified as major epitope recognized by IgG1>IgG2 = IgG4>IgG3, IgA>IgM antibodies and a C-terminal peptide represented another major peptide epitope for the four IgG subclasses. By contrast, gp41-derived-peptides were mainly recognized by IgG1 but not by the other IgG subclasses, IgA or IgM. Among the non-surface proteins, protease, reverse transcriptase+RNAseH, integrase, as well as the capsid and matrix proteins were the most frequently and strongly recognized antigens which showed broad IgG subclass and IgA reactivity. Specificities and magnitudes of antibody responses in African patients were stable during disease and antiretroviral treatment, and persisted despite severe T cell loss. Using a comprehensive panel of gp120, gp41 peptides and recombinant non-surface proteins of HIV-1 clade C we found an almost identical antibody recognition profile in African and European patients regarding epitopes and involved IgG-sublass, IgA- and IgM-responses. Immune recognition of gp120 peptides and non-surface proteins involved all four IgG subclasses and was indicative of a mixed Th1/Th2 immune response. The HIV-1 clade C proteome-based test allowed diagnosis and monitoring of antibody responses in the course of HIV-infections and assessment of isotype and subclass responses. PMID:25658330

  3. Does low IgA in human milk predispose the infant to development of cow's milk allergy?

    PubMed

    Järvinen, K M; Laine, S T; Järvenpää, A L; Suomalainen, H K

    2000-10-01

    We sought a relationship between total and cow's milk-specific IgA levels in colostrum and human milk and subsequent development of cow's milk allergy (CMA) in the breast-fed infant. The study included 87 nursing mothers and their infants (age, 2 d to 7 mo), followed prospectively up to 1 y. At 1 y, 48 mothers (69% with an atopic constitution) had an infant with CMA, verified by clinical cow's milk challenge, eight (38% with an atopic constitution) had a baby who had had protracted infantile colic but no CMA (disease control group), and 31 (23% with an atopic constitution) had a healthy infant. Total breast-milk IgA was measured by radial immunodiffusion, and IgA antibodies to cow's milk were measured by ELISA during the breast-feeding period. The levels of total and cow's milk-specific IgA antibodies in colostrum and human milk were significantly lower in the mothers whose baby later developed CMA [estimated third day value, 0.38 g/L (95% confidence interval, 0. 24-0.82)] than in the ones whose infant remained healthy or had had infantile colic but not CMA [0.82 g/L (95% confidence interval, 0. 99-1.51); p < 0.05]. The infants developed CMA significantly more often if the concentration of total IgA antibodies in milk was <0.25 g/L, when measured between 6 d and 4 wk postpartum [sensitivity, 0. 55; specificity, 0.92; odds ratio, 14.7 (95% confidence interval, 3. 1-70.2); p < 0.001]. The levels of cow's milk-specific IgA positively correlated with the levels of total IgA but not with the development of CMA in the infant. The levels of total or cow's milk-specific IgA did not correlate with maternal atopy. IgA antibodies in colostrum and human milk may prevent antigen entry at the intestinal surface of the breast-fed infant. A low IgA content in human milk may lead to defective exclusion of food antigens and thus predispose an offspring to develop food allergies.

  4. Nasal IgA Provides Protection against Human Influenza Challenge in Volunteers with Low Serum Influenza Antibody Titre.

    PubMed

    Gould, Victoria M W; Francis, James N; Anderson, Katie J; Georges, Bertrand; Cope, Alethea V; Tregoning, John S

    2017-01-01

    In spite of there being a number of vaccines, influenza remains a significant global cause of morbidity and mortality. Understanding more about natural and vaccine induced immune protection against influenza infection would help to develop better vaccines. Virus specific IgG is a known correlate of protection, but other factors may help to reduce viral load or disease severity, for example IgA. In the current study we measured influenza specific responses in a controlled human infection model using influenza A/California/2009 (H1N1) as the challenge agent. Volunteers were pre-selected with low haemagglutination inhibition (HAI) titres in order to ensure a higher proportion of infection; this allowed us to explore the role of other immune correlates. In spite of HAI being uniformly low, there were variable levels of H1N1 specific IgG and IgA prior to infection. There was also a range of disease severity in volunteers allowing us to compare whether differences in systemic and local H1N1 specific IgG and IgA prior to infection affected disease outcome. H1N1 specific IgG level before challenge did not correlate with protection, probably due to the pre-screening for individuals with low HAI. However, the length of time infectious virus was recovered from the nose was reduced in patients with higher pre-existing H1N1 influenza specific nasal IgA or serum IgA. Therefore, IgA contributes to protection against influenza and should be targeted in vaccines.

  5. Purification and functional characterization of mucosal IgA from vaccinated and SIV-infected rhesus macaques.

    PubMed

    Musich, Thomas; Demberg, Thorsten; Morgan, Ian L; Estes, Jacob D; Franchini, Genoveffa; Robert-Guroff, Marjorie

    2015-06-01

    Vaccine-induced mucosal antibodies are often evaluated using small volumes of secretory fluids. However, fecal matter containing mucosal IgA is abundant. We purified fecal IgA from five SIV-vaccinated and five SIV-infected rhesus macaques by sequential affinity chromatography. The purified IgA was dimeric by native PAGE, contained secretory component, and was analogous to IgA in colostrum and vaginal fluid by western blot. IgA from one infected and four vaccinated animals neutralized H9-derived SIV(mac)251 with IC(50)s as low as 1 μg/mL. Purified IgAs inhibited transcytosis and exhibited phagocytic activity, the latter significantly correlated with SIV(mac)251 Env-specific IgA in the purified samples. Among different affinity resins, peptide M was optimal compared to jacalin, anti-monkey IgA and SSL7 for IgA purification, as confirmed using tandem peptide M/anti-monkey IgA columns. Fecal IgA provided material sufficient for several assays relevant to protective efficacy, and was shown to be multifunctional. Our approach is potentially applicable to human clinical studies. Published by Elsevier Inc.

  6. Thymopentin treatment of selective IgA deficiency.

    PubMed

    Fiorilli, M; Quinti, I; Russi, G; Seminara, R; Ensoli, B; Aiuti, F

    1985-01-01

    Thymic hormones have been shown to modulate immunoglobulin production in a number of experiments and it is generally agreed that this action is mediated by modulation of helper and/or suppressor T cell activities. The possibility of upregulating the immunoglobulins is of particular relevance in patients with hypogammaglobulinemias and this paper reports on the results of thymopentin treatment in 9 patients with selective IgA deficiency. Two out of 4 patients responded positively in an open-label trial; in one the serum IgA values remained stable up to 8 weeks after discontinuation of treatment whereas there was a rapid fall in the other. Both responders had consistently normal T4/T8 ratios during the treatment, whereas the nonresponders revealed high ratios with large fluctuations of the T4/T8 ratio. In a subsequent (still ongoing) double-blind trial in 5 patients (3 thymopentin, 2 placebo) no significant change of serum or secretory IgA levels has been observed. Taken together, the data suggest that the tested dose regimen of thymopentin (i.e. daily i.m. injections of 1 mg/kg for 2 weeks, then same dose 3 time weekly for 10 weeks) may only work in a subset of patients with selective IgA deficiency. In the present study we did not attempt to distinguish to which of the three known subgroups the 9 patients belonged, nor did we try alternative dose regimens of thymopentin.

  7. Selective deficiency of IgA

    MedlinePlus

    ... Complications Autoimmune disorders such as rheumatoid arthritis , systemic lupus erythematosus , and celiac sprue may develop. People with IgA deficiency may develop antibodies to IgA. As a result, they can have severe, even life-threatening reactions ...

  8. Laser fiber cleaving techniques: effects on tip morphology and power output.

    PubMed

    Vassantachart, Janna M; Lightfoot, Michelle; Yeo, Alexander; Maldonado, Jonathan; Li, Roger; Alsyouf, Muhannad; Martin, Jacob; Lee, Michael; Olgin, Gaudencio; Baldwin, D Duane

    2015-01-01

    Proper cleaving of reusable laser fibers is needed to maintain optimal functionality. This study quantifies the effect of different cleaving tools on power output of the holmium laser fiber and demonstrates morphologic changes using microscopy. The uncleaved tips of new 272 μm reusable laser fibers were used to obtain baseline power transmission values at 3 W (0.6 J, 5 Hz). Power output for each of four cleaving techniques-11-blade scalpel, scribe pen cleaving tool, diamond cleaving wheel, and suture scissors-was measured in a single-blinded fashion. Dispersion of light from the fibers was compared with manufacturer specifications and rated as "ideal," "acceptable," or "unacceptable" by blinded reviewers. The fiber tips were also imaged using confocal and scanning electron microscopy. Independent samples Kruskal-Wallis test and chi square were used for statistical analysis (α<0.05). New uncleaved fiber tips transmitted 3.04 W of power and were used as a reference (100%). The scribe pen cleaving tool produced the next highest output (97.1%), followed by the scalpel (83.4%), diamond cleaving wheel (77.1%), and suture scissors (61.7%), a trend that was highly significant (P<0.001). On pairwise comparison, no difference in power output was seen between the uncleaved fiber tips and those cleaved with the scribe pen (P=1.0). The rating of the light dispersion patterns from the different cleaving methods followed the same trend as the power output results (P<0.001). Microscopy showed that the scribe pen produced small defects along the fiber cladding but maintained a smooth, flat core surface. The other cleaving techniques produced defects on both the core and cladding. Cleaving techniques produce a significant effect on the initial power transmitted by reusable laser fibers. The scribe pen cleaving tool produced the most consistent and highest average power output.

  9. Variants in Complement Factor H and Complement Factor H-Related Protein Genes, CFHR3 and CFHR1, Affect Complement Activation in IgA Nephropathy.

    PubMed

    Zhu, Li; Zhai, Ya-Ling; Wang, Feng-Mei; Hou, Ping; Lv, Ji-Cheng; Xu, Da-Min; Shi, Su-Fang; Liu, Li-Jun; Yu, Feng; Zhao, Ming-Hui; Novak, Jan; Gharavi, Ali G; Zhang, Hong

    2015-05-01

    Complement activation is common in patients with IgA nephropathy (IgAN) and associated with disease severity. Our recent genome-wide association study of IgAN identified susceptibility loci on 1q32 containing the complement regulatory protein-encoding genes CFH and CFHR1-5, with rs6677604 in CFH as the top single-nucleotide polymorphism and CFHR3-1 deletion (CFHR3-1∆) as the top signal for copy number variation. In this study, to explore the clinical effects of variation in CFH, CFHR3, and CFHR1 on IgAN susceptibility and progression, we enrolled two populations. Group 1 included 1178 subjects with IgAN and available genome-wide association study data. Group 2 included 365 subjects with IgAN and available clinical follow-up data. In group 1, rs6677604 was associated with mesangial C3 deposition by genotype-phenotype correlation analysis. In group 2, we detected a linkage between the rs6677604-A allele and CFHR3-1∆ and found that the rs6677604-A allele was associated with higher serum levels of CFH and lower levels of the complement activation split product C3a. Furthermore, CFH levels were positively associated with circulating C3 levels and negatively associated with mesangial C3 deposition. Moreover, serum levels of the pathogenic galactose-deficient glycoform of IgA1 were also associated with the degree of mesangial C3 deposition in patients with IgAN. Our findings suggest that genetic variants in CFH, CFHR3, and CFHR1 affect complement activation and thereby, predispose patients to develop IgAN. Copyright © 2015 by the American Society of Nephrology.

  10. Distribution of IgA subclass response to Coxiella burnetii in patients with acute and chronic Q fever.

    PubMed

    Camacho, M T; Outschoorn, I; Echevarría, C; Kovácová, E; Yebra, M; Maté, I; Auffray, P; Téllez, A

    1998-07-01

    The progression of Coxiella burnetii infection to acute or chronic Q fever has been attributed to biological characteristics of the bacterium and to the host immune response. We measured whether serum levels of total and specific subclasses IgA1 and IgA2 could be correlated with the course of disease in acute and chronic Q fever infections, and with the occurrence of endocarditis. In patients with chronic infection, total IgA2 levels were significantly increased. Q-fever-specific IgA1 antibodies were detectable in both acute and chronic infections, but only patients with endocarditis had IgA2 antibodies to C. burnetii phase II antigens. These findings indicate that the measurement of IgA subclasses may be a useful aid in the serological diagnosis of Q fever. Our results reinforce the idea that immunologically mediated host factors are important in the pathogenesis of Q fever and in the disease outcome of this infection. Copyright 1998 Academic Press.

  11. Serological testing for coeliac disease in Type 1 diabetes mellitus: is immunoglobulin A level measurement necessary?

    PubMed

    Kurien, M; Leeds, J S; Hopper, A D; Wild, G; Egner, W; Tesfaye, S; Hadjivassiliou, M; Sanders, D S

    2013-07-01

    Immunoglobulin A (IgA) measurement is advocated when case finding for coeliac disease in patients with Type 1 diabetes mellitus. Currently, there is a paucity of contemporary studies assessing IgA deficiency in Type 1 diabetes. This study evaluates the prevalence of IgA deficiency in individuals with Type 1 diabetes, compared with patients with coeliac disease and control subjects. In addition, we evaluate whether routine IgA measurement is justifiable when case finding for coeliac disease in patients with Type 1 diabetes. All patients were assessed using IgA endomysial antibodies, IgA anti-tissue transglutaminase antibodies and total IgA levels. Altogether, 2434 individuals were tested: 1000 patients with Type 1 diabetes, 234 patients with coeliac disease and 1200 population control subjects. Definitive IgA deficiency was defined as total IgA levels < 0.07 g/l. The prevalence of IgA deficiency was significantly more common in patients with Type 1 diabetes (0.9%, n = 9/1000; P = 0.036) and coeliac disease (1.29%, n = 3/234; P = 0.041) when compared with population control subjects (prevalence of 0.17%, 2/1200). No statistical difference between Type 1 diabetes and coeliac disease for IgA deficiency was identified (P = 0.87). Of patients in the group with Type 1 diabetes, 3.3% (33/1000) had coeliac disease, and of those only one patient had IgA deficiency leading to an antibody-negative presentation. Both IgA-deficient individuals within the population control subjects had normal duodenal biopsies and no relevant symptoms. IgA deficiency is more common in Type 1 diabetes compared with population control subjects. Despite this, very few individuals with Type 1 diabetes and IgA deficiency appear to have villous atrophy on biopsy. These outcomes question the practice of routine IgA measurement when case finding for coeliac disease in patients with Type 1 diabetes. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK.

  12. Cutting Edge: Active TGF-β1 Released from GARP/TGF-β1 Complexes on the Surface of Stimulated Human B Lymphocytes Increases Class-Switch Recombination and Production of IgA.

    PubMed

    Dedobbeleer, Olivier; Stockis, Julie; van der Woning, Bas; Coulie, Pierre G; Lucas, Sophie

    2017-07-15

    Production of active TGF-β is regulated at a posttranslational level and implies release of the mature cytokine dimer from the inactive, latent TGF-β precursor. There are several cell-type specific mechanisms of TGF-β activation. We identified a new mechanism operating on the surface of human regulatory T cells and involving membrane protein GARP, which binds latent TGF-β1. The paracrine activity of regulatory T cell-derived TGF-β1 contributes to immunosuppression and can be inhibited with anti-GARP Abs. Whether other immune cell types use surface GARP to activate latent TGF-β1 was not known. We show in this study that stimulated, human B lymphocytes produce active TGF-β1 from surface GARP/latent TGF-β1 complexes with isotype switching to IgA production. Copyright © 2017 by The American Association of Immunologists, Inc.

  13. Cytokine profile of NALT during acute stress and its possible effect on IgA secretion.

    PubMed

    Gutiérrez-Meza, Juan Manuel; Jarillo-Luna, Rosa Adriana; Rivera-Aguilar, Victor; Miliar-García, Angel; Campos-Rodríguez, Rafael

    2017-08-01

    Stress stimuli affect the immune system responses that occur at mucosal membranes, particularly IgA secretion. It has been suggested that acute stress increases the levels of IgA and that sympathetic innervation plays an important role in this process. We herein explore in a murine model how acute stress affects the Th1/Th2/Treg cytokine balance in NALT, and the possible role of glucocorticoids in this effect. Nine-week-old male CD1 mice were divided into three groups: unstressed (control), stressed (subjected to 4h of immobilization), and stressed after pretreatment with a single dose of the corticosterone receptor antagonist RU-486. The parameters evaluated included plasma corticosterone and epinephrine, IgA levels in nasal fluid (by ELISA), the percentage of CD19 + B220 + IgA + lymphocytes and CD138 + IgA + plasma cells, and the mRNA expression of heavy α chain, J chain and pIgR. Moreover, the gene and protein expression of Th1 cytokines (TNFα, IL-2 and INF-γ), Th2 cytokines (IL-4 and IL-5) and Treg cytokines (IL-10 and TGFβ) were determined in nasal mucosa. The results show that acute stress generated a shift towards the dominance of an anti-inflammatory immune response (Th2 and Treg cytokines), evidenced by a significant rise in the amount of T cells that produce IL4, IL-5 and IL-10. This immune environment may favor IgA biosynthesis by CD138 + IgA + plasma cells, a process mediated mostly by glucocorticoids. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  14. The dog as a genetic model for immunoglobulin A (IgA) deficiency: identification of several breeds with low serum IgA concentrations.

    PubMed

    Olsson, Mia; Frankowiack, Marcel; Tengvall, Katarina; Roosje, Petra; Fall, Tove; Ivansson, Emma; Bergvall, Kerstin; Hansson-Hamlin, Helene; Sundberg, Katarina; Hedhammar, Ake; Lindblad-Toh, Kerstin; Hammarström, Lennart

    2014-08-15

    Immunoglobulin A (IgA) serves as the basis of the secretory immune system by protecting the lining of mucosal sites from pathogens. In both humans and dogs, IgA deficiency (IgAD) is associated with recurrent infections of mucosal sites and immune-mediated diseases. Low concentrations of serum IgA have previously been reported to occur in a number of dog breeds but no generally accepted cut-off value has been established for canine IgAD. The current study represents the largest screening to date of IgA in dogs in terms of both number of dogs (n=1267) and number of breeds studied (n=22). Serum IgA concentrations were quantified by using capture ELISA and were found to vary widely between breeds. We also found IgA to be positively correlated with age (p<0.0001). Apart from the two breeds previously reported as predisposed to low IgA (Shar-Pei and German shepherd), we identified six additional breeds in which ≥ 10% of all tested dogs had very low (<0.07 g/l) IgA concentrations (Hovawart, Norwegian elkhound, Nova Scotia duck tolling retriever, Bullterrier, Golden retriever and Labrador retriever). In addition, we discovered low IgA concentrations to be significantly associated with canine atopic dermatitis (CAD, p<0.0001) and pancreatic acinar atrophy (PAA, p=0.04) in German shepherds. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. A Mutation in UL15 of Herpes Simplex Virus 1 That Reduces Packaging of Cleaved Genomes▿

    PubMed Central

    Yang, Kui; Wills, Elizabeth G.; Baines, Joel D.

    2011-01-01

    Herpesvirus genomic DNA is cleaved from concatemers that accumulate in infected cell nuclei. Genomic DNA is inserted into preassembled capsids through a unique portal vertex. Extensive analyses of viral mutants have indicated that intact capsids, the portal vertex, and all components of a tripartite terminase enzyme are required to both cleave and package viral DNA, suggesting that DNA cleavage and packaging are inextricably linked. Because the processes have not been functionally separable, it has been difficult to parse the roles of individual proteins in the DNA cleavage/packaging reaction. In the present study, a virus bearing the deletion of codons 400 to 420 of UL15, encoding a terminase component, was analyzed. This virus, designated vJB27, failed to replicate on noncomplementing cells but cleaved concatemeric DNA to ca. 35 to 98% of wild-type levels. No DNA cleavage was detected in cells infected with a UL15-null virus or a virus lacking UL15 codons 383 to 385, comprising a motif proposed to couple ATP hydrolysis to DNA translocation. The amount of vJB27 DNA protected from DNase I digestion was reduced compared to the wild-type virus by 6.5- to 200-fold, depending on the DNA fragment analyzed, thus indicating a profound defect in DNA packaging. Capsids containing viral DNA were not detected in vJB27-infected cells, as determined by electron microscopy. These data suggest that pUL15 plays an essential role in DNA translocation into the capsid and indicate that this function is separable from its role in DNA cleavage. PMID:21880766

  16. Disruption of Smad4 Expression in T Cells Leads to IgA Nephropathy-Like Manifestations

    PubMed Central

    Yamashita, Michifumi; Choi, Sung Hee; Tomino, Yasuhiko; Letterio, John J.; Emancipator, Steven N.

    2013-01-01

    The link between glomerular IgA nephropathy (IgAN) and T helper 2 (Th2) response has been implicated, however, the mechanisms are poorly defined because of the lack of an appropriate model. Here we report a novel murine model characterized by lineage-restricted deletion of the gene encoding MAD homologue 4 (Smad4) in T cells (Smad4co/co;Lck-cre). Loss of Smad4 expression in T cells results in overproduction of Th2 cytokines and high serum IgA levels. We found that Smad4co/co;Lck-cre mice exhibited massive glomerular IgA deposition, increased albumin creatinine ratio, aberrant glycosylated IgA, IgA complexed with IgG1 and IgG2a, and polymeric IgA, all known features of IgAN in humans. Furthermore, we examined the β1, 4-galactosyltransferases (β4GalT) enzyme which is involved in the synthesis of glycosylated murine IgA, and we found reduced β4GalT2 and β4GalT4 mRNA levels in B cells. These findings indicate that Smad4co/co;Lck-cre mice could be a useful model for studying the mechanisms between IgAN and Th2 response, and further, disruption of Smad4-dependent signaling in T cells may play an important role in the pathogenesis of human IgAN and contributing to a Th2 T cell phenotype. PMID:24223846

  17. Disrupted-in-Schizophrenia-1 Attenuates Amyloid-β Generation and Cognitive Deficits in APP/PS1 Transgenic Mice by Reduction of β-Site APP-Cleaving Enzyme 1 Levels

    PubMed Central

    Deng, Qing-Shan; Dong, Xing-Yu; Wu, Hao; Wang, Wang; Wang, Zhao-Tao; Zhu, Jian-Wei; Liu, Chun-Feng; Jia, Wei-Qiang; Zhang, Yan; Schachner, Melitta; Ma, Quan-Hong; Xu, Ru-Xiang

    2016-01-01

    Disrupted-in-Schizophrenia-1 (DISC1) is a genetic risk factor for a wide range of major mental disorders, including schizophrenia, major depression, and bipolar disorders. Recent reports suggest a potential role of DISC1 in the pathogenesis of Alzheimer's disease (AD), by referring to an interaction between DISC1 and amyloid precursor protein (APP), and to an association of a single-nucleotide polymorphism in a DISC1 intron and late onset of AD. However, the function of DISC1 in AD remains unknown. In this study, decreased levels of DISC1 were observed in the cortex and hippocampus of 8-month-old APP/PS1 transgenic mice, an animal model of AD. Overexpression of DISC1 reduced, whereas knockdown of DISC1 increased protein levels, but not mRNA levels of β-site APP-Cleaving Enzyme 1 (BACE1), a key enzyme in amyloid-β (Aβ) generation. Reduction of BACE1 protein levels by overexpression of DISC1 was accompanied by an accelerating decline rate of BACE1, and was blocked by the lysosomal inhibitor chloroquine, rather than proteasome inhibitor MG-132. Moreover, overexpression of DISC1 in the hippocampus with an adeno-associated virus reduced the levels of BACE1, soluble Aβ40/42, amyloid plaque density, and rescued cognitive deficits of APP/PS1 transgenic mice. These results indicate that DISC1 attenuates Aβ generation and cognitive deficits of APP/PS1 transgenic mice through promoting lysosomal degradation of BACE1. Our findings provide new insights into the role of DISC1 in AD pathogenesis and link a potential function of DISC1 to the psychiatric symptoms of AD. PMID:26062786

  18. Clinical and pathological analysis of IgA nephropathy with chronic renal failure.

    PubMed

    Liu, Yuyuan; Hu, Qinfeng; Shen, Ping; Tang, Li; Yuan, Gang; Zhou, Yongmei; Chai, Huaqi

    2016-10-01

    To investigative clinical and pathological characteristics of IgA nephropathy with chronic renal failure. Clinical and pathological findings from 65 cases of IgA nephropathy with chronic renal failure were reviewed. Pathological characteristics of all the cases were analyzed according to WHO definition and Oxford Classification. Evaluating the severity of pathological lesions by the Katafuchi R semiquantitative scoring system, and analyzing their relationship with clinical indexes of renal function. Of all 65 cases the male and female ratio was 1.4, and the mean age was 37 ± 13 years old. Levels of systolic pressure, mean arterial pressure (MAP), blood urea nitrogen (BUN), serum creatinine (Scr), uric acid (UA), album (Alb), serum IgG and 24 h urinary protein were related with eGRF level (p < 0.05, respectively). The most common pathological type was proliferative sclerosis glomerulonephritis (PSGN) and M1S1E0T0 according to WHO definition and Oxford Classification, respectively, and most of the 65 cases had glomerulosclerosis. Simple IgA deposition was the most common immunopathologic type. Of all the cases, 44.6% accompanied with C3 while 4.6% with C1q. Further analysis revealed there were no relationships between severity of pathological lesion and levels of clinical indexes (Scr and eGRF) (p > 0.05). IgA nephropathy with chronic renal failure usually occurred in young adults, and it had severe clinical condition and pathological changes, while there was no significant relationship between them.

  19. Comparison of interferon and bovine herpesvirus-1-specific IgA levels in nasal secretions of dairy cattle administered an intranasal modified live viral vaccine prior to calving or on the day of calving.

    PubMed

    Cortese, Victor S; Woolums, Amelia; Hurley, David J; Berghaus, Roy; Bernard, John K; Short, Thomas H

    2017-05-01

    Thirty-two Holstein cows were allocated to receive intranasal vaccination with modified live bovine herpesvirus-1 (BHV-1), bovine respiratory syncytial virus (BRSV) and parainfluenza type 3 virus (PI3V) vaccine either two weeks prior to their projected calving date, or within 24h after calving. Nasal secretions were collected twice at a 12-h interval on the day prior to vaccination (day 0) and at 2, 4, 7, 10 and 14days post vaccination to measure interferon (IFN) alpha, IFN-beta, IFN-gamma, and BHV-1-specific IgA by ELISA. Serum neutralizing antibody titers to BHV-1 and BRSV were measured on days 0, 7, and 14. There was a significant treatment effect (p<0.0004) and interaction (p<0.05) on nasal BHV-1 IgA levels, with higher IgA levels in cows vaccinated within 24h after calving. There was a significant treatment effect on nasal IFN-gamma concentration (p<0.05) and on nasal total IFN concentration (p<0.05), with higher IFN-gamma and total IFN concentrations seen in cows vaccinated within 24h after calving. There was no significant treatment or interaction effect on nasal IFN-alpha or IFN-beta concentrations, or on serum neutralizing titers to BRSV. In spite of prior viral vaccination during the previous lactation, cows vaccinated on the day of calving responded to an intranasal viral vaccination with increased concentrations of IFN-gamma and increased titers of IgA following vaccination which was significantly higher than cows vaccinated precalving. This study is the first to examine respiratory mucosal responses in immunologically mature dairy cattle vaccinated intranasally before and after calving. Copyright © 2017. Published by Elsevier B.V.

  20. Saliva secretory IgA antibodies against molds and mycotoxins in patients exposed to toxigenic fungi.

    PubMed

    Vojdani, Aristo; Kashanian, Albert; Vojdani, Elroy; Campbell, Andrew W

    2003-11-01

    Upper respiratory exposure to different environmental antigens results first in the activation of mucosal immunity and production of IgA antibodies in different secretions including saliva. Despite this there is no study, which addresses secretory antibodies against molds and mycotoxins. The purpose of this study was to evaluate mold-specific salivary IgA in individuals exposed to molds and mycotoxins in a water-damaged building environment. Saliva IgA antibody levels against seven different molds and two mycotoxins were studied in 40 patients exposed to molds and in 40 control subjects. Mold-exposed patients showed significantly higher levels of salivary IgA antibodies against one or more mold species. A majority of patients with high IgA antibodies against molds exhibited elevation in salivary IgA against mycotoxins, as well. These IgA antibodies against molds and mycotoxins are specific, since using molds and mycotoxins in immune absorption could reduce antibody levels, significantly. Detection of high counts of molds in water-damaged buildings, strongly suggests the existence of a reservoir of mold spores in the environment. This viable microbial activity with specific mold and mycotoxin IgA in saliva may assist in the diagnosis of mold exposure. Whether mold and mycotoxin specific IgA antibodies detected in saliva are indicative of the role of IgA antibodies in the late phase of type-1 hypersensitivity reaction or in type-2 and type-3 delayed sensitivities is a matter that warrants further investigation.

  1. Ripple formation on atomically flat cleaved Si surface with roughness of 0.038 nm rms by low-energy Ar{sup 1+} ion bombardment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pahlovy, Shahjada A.; Mahmud, S. F.; Yanagimoto, K.

    The authors have conducted research regarding ripple formation on an atomically flat cleaved Si surface by low-energy Ar{sup +} ion bombardment. The cleaved atomically flat and smooth plane of a Si wafer was obtained by cutting vertically against the orientation of a Si (100) wafer. Next, the cleaved surface was sputtered by a 1 keV Ar{sup +} ion beam at ion-incidence angles of 0 deg., 60 deg., 70 deg., and 80 deg. The results confirm the successful ripple formation at ion-incidence angles of 60 deg. - 80 deg. and that the wavelength of the ripples increases with the increase ofmore » the ion-incidence angle, as well as the inverse of ion doses. The direction of the ripple also changes from perpendicular to parallel to the projection of the ion-beam direction along the surface with the increasing ion-incidence angle. The authors have also observed the dose effects on surface roughness of cleaved Si surface at the ion-incidence angle of 60 deg., where the surface roughness increases with the increased ion dose. Finally, to understand the roughening mechanism, the authors studied the scaling behavior, measured the roughness exponent {alpha}, and compared the evolution of scaling regimes with Cuerno's one-dimensional simulation results.« less

  2. The higher frequency of IgA deficiency among Swedish twins is not explained by HLA haplotypes.

    PubMed

    Frankowiack, M; Kovanen, R-M; Repasky, G A; Lim, C K; Song, C; Pedersen, N L; Hammarström, L

    2015-01-01

    Serum immunoglobulin A (IgA) concentrations were determined in 12 600 adult Swedish twins, applying a high-throughput reverse-phase protein microarray technique. The prevalence of IgA deficiency (IgAD) was found to be 1:241 in monozygotic (MZ) twins and 1:198 in dizygotic (DZ) twins. Hence, the prevalence in twins is markedly elevated as compared with the normal Swedish adult population (1:600). The twins did not show a difference in the frequency of HLA haplotypes in comparison with almost 40 000 healthy Swedish controls. As expected, the risk-conveying HLA alleles A*01, B*08 and DRB1*01 were overrepresented among the IgAD twins and were also associated with significantly lower mean serum IgA concentrations in the twin cohort. In contrast, significantly higher mean IgA concentrations were found among individuals carrying the protective HLA alleles B*07 and DRB1*15. Exome sequencing data from two MZ twin pairs discordant for the deficiency showed no differences between the siblings. Model fitting analyses derived a heritability of 35% and indicate that genetic influences are modestly important for IgAD. The probandwise concordance rates for IgAD were found to be 31% for MZ and 13% for DZ twins.

  3. Vertically transmitted fecal IgA levels distinguish extra-chromosomal phenotypic variation

    PubMed Central

    Wallace, Meghan A.; D, Carey-Ann; Burnham; Virgin, Herbert W.; Stappenbeck, Thaddeus S.

    2014-01-01

    Summary The proliferation of genetically modified mouse models has exposed phenotypic variation between investigators and institutions that has been challenging to control1-5. In many cases, the microbiota is the presumed culprit of the variation. Current solutions to account for phenotypic variability include littermate and maternal controls or defined microbial consortia in gnotobiotic mice6,7. In conventionally raised mice, the microbiome is transmitted from the dam2,8,9. Here we show that microbially–driven dichotomous fecal IgA levels in WT mice within the same facility mimic the effects of chromosomal mutations. We observed in multiple facilities that vertically-transmissible bacteria in IgA-Low mice dominantly lowered fecal IgA levels in IgA-High mice after cohousing or fecal transplantation. In response to injury, IgA-Low mice showed increased damage that was transferable by fecal transplantation and driven by fecal IgA differences. We found that bacteria from IgA-Low mice degraded the secretory component (SC) of SIgA as well as IgA itself. These data indicate that phenotypic comparisons between mice must take into account the non-chromosomal hereditary variation between different breeders. We propose fecal IgA as one marker of microbial variability and conclude that cohousing and/or fecal transplantation enables analysis of progeny from different dams. PMID:25686606

  4. Inflammation-induced IgA+ cells dismantle anti-liver cancer immunity

    PubMed Central

    Shalapour, Shabnam; Lin, Xue-Jia; Bastian, Ingmar N.; Brain, John; Burt, Alastair D.; Aksenov, Alexander A.; Vrbanac, Alison F.; Li, Weihua; Perkins, Andres; Matsutani, Takaji; Zhong, Zhenyu; Dhar, Debanjan; Navas-Molina, Jose A.; Xu, Jun; Loomba, Rohit; Downes, Michael; Yu, Ruth T.; Evans, Ronald M.; Dorrestein, Pieter C.; Knight, Rob; Benner, Christopher; Anstee, Quentin M.; Karin, Michael

    2018-01-01

    The role of adaptive immunity in early cancer development is controversial. Here we show that chronic inflammation and fibrosis in humans and mice with non-alcoholic fatty liver disease is accompanied by accumulation of liver-resident immunoglobulin-A-producing (IgA+) cells. These cells also express programmed death ligand 1 (PD-L1) and interleukin-10, and directly suppress liver cytotoxic CD8+ T lymphocytes, which prevent emergence of hepatocellular carcinoma and express a limited repertoire of T-cell receptors against tumour-associated antigens. Whereas CD8+ T-cell ablation accelerates hepatocellular carcinoma, genetic or pharmacological interference with IgA+ cell generation attenuates liver carcinogenesis and induces cytotoxic T-lymphocyte-mediated regression of established hepatocellular carcinoma. These findings establish the importance of inflammation-induced suppression of cytotoxic CD8+ T-lymphocyte activation as a tumour-promoting mechanism. PMID:29144460

  5. Borrelia burgdorferi-specific IgA in Lyme Disease.

    PubMed

    D'Arco, Christina; Dattwyler, Raymond J; Arnaboldi, Paul M

    2017-05-01

    The laboratory diagnosis of Lyme disease is currently dependent on the detection of IgM and IgG antibodies against Borrelia burgdorferi, the causative agent of the disease. The significance of serum IgA against B. burgdorferi remains unclear. The production of intrathecal IgA has been noted in patients with the late Lyme disease manifestation, neuroborreliosis, but production of antigen-specific IgA during early disease has not been evaluated. In the current study, we assessed serum IgA binding to the B. burgdorferi peptide antigens, C6, the target of the FDA-cleared C6 EIA, and FlaB(211-223)-modVlsE(275-291), a peptide containing a Borrelia flagellin epitope linked to a modified VlsE sequence, in patients with early and late Lyme disease. Specific IgA was detected in 59 of 152 serum samples (38.8%) from early Lyme disease patients. Approximately 50% of early Lyme disease patients who were seropositive for peptide-specific IgM and/or IgG were also seropositive for peptide-specific IgA. In a subpopulation of patients, high peptide-specific IgA could be correlated with disseminated disease, defined as multiple erythema migrans lesions, and neurological disease complications. These results suggest that there may be an association between elevated levels of antigen-specific IgA and particular disease manifestations in some patients with early Lyme disease. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Biomarkers for IgA nephropathy on the basis of multi-hit pathogenesis.

    PubMed

    Suzuki, Hitoshi

    2018-05-08

    IgA nephropathy (IgAN) is the most prevalent glomerular disease worldwide and is associated with a poor prognosis. Development of curative treatment strategies and approaches for early diagnosis is necessary. Renal biopsy is the gold standard for the diagnosis and assessment of disease activity. However, reliable biomarkers are needed for the noninvasive diagnosis of this disease and to more fully delineate the risk of progression. With regard to the pathogenesis of IgAN, the multi-hit hypothesis, including production of galactose-deficient IgA1 (Gd-IgA1; Hit 1), IgG or IgA autoantibodies that recognize Gd-IgA1 (Hit 2), and their subsequent immune complexes formation (Hit 3) and glomerular deposition (Hit 4), has been widely supported by many studies. Although the prognostic values of several biomarkers have been discussed, we recently developed a highly sensitive and specific diagnostic method by measuring serum levels of Gd-IgA1 and Gd-IgA1-containing immune complexes. In addition, urinary Gd-IgA1 may represent a disease-specific biomarker for IgAN. We also confirmed that there is a significant correlation between serum levels of these effector molecules and disease activity, suggesting that each can be considered a practical surrogate marker of therapeutic response. Thus, these disease-oriented specific serum and urine biomarkers may be useful for screening of potential IgAN with isolated hematuria, earlier diagnosis, disease activity, and eventually, response to treatment. In this review, we discuss these concepts, with a focus on potential clinical applications of these biomarkers.

  7. IgA Function in Relation to the Intestinal Microbiota.

    PubMed

    Macpherson, Andrew J; Yilmaz, Bahtiyar; Limenitakis, Julien P; Ganal-Vonarburg, Stephanie C

    2018-04-26

    IgA is the dominant immunoglobulin isotype produced in mammals, largely secreted across the intestinal mucosal surface. Although induction of IgA has been a hallmark feature of microbiota colonization following colonization in germ-free animals, until recently appreciation of the function of IgA in host-microbial mutualism has depended mainly on indirect evidence of alterations in microbiota composition or penetration of microbes in the absence of somatic mutations in IgA (or compensatory IgM). Highly parallel sequencing techniques that enable high-resolution analysis of either microbial consortia or IgA sequence diversity are now giving us new perspectives on selective targeting of microbial taxa and the trajectory of IgA diversification according to induction mechanisms, between different individuals and over time. The prospects are to link the range of diversified IgA clonotypes to specific antigenic functions in modulating the microbiota composition, position and metabolism to ensure host mutualism.

  8. Nationwide epidemiological survey of childhood IgA vasculitis associated hospitalization in the USA.

    PubMed

    Okubo, Yusuke; Nochioka, Kotaro; Sakakibara, Hiroshi; Hataya, Hiroshi; Terakawa, Toshiro; Testa, Marcia; Sundel, Robert P

    2016-11-01

    At the national level, IgA vasculitis-related hospitalizations among children in the USA are scarce. Furthermore, nationwide epidemiology and hospital course of children with IgA vasculitis have not been fully described in the USA, and disparities by race/ethnicity remain unknown. Hospital discharge records of patients aged 19 years or younger were obtained from the 2003, 2006, 2009, and 2012 Kids' Inpatient Database, and they were weighted to estimate the annual hospitalization rates with respect to age, gender, and race/ethnicity in the USA. Annual hospitalization rates were calculated using weighted case estimates and US census data. Negative binomial regression was used to ascertain the factors associated with length of hospital stay. Total annual hospitalization rates showed a significant decreasing trend, ranging from 2.45 per 100,000 children in 2003 to 1.89 per 100,000 children in 2012 (p < 0.001). The peak ages of the hospitalized children with IgA vasculitis were 2 and 7 years, and male-to-female ratios were 1.38-1.44. Factors associated with length of hospital stay were patients' ages (10-14 and 15-19 years), race/ethnicity (Hispanic, Asian, and Pacific Islander), comorbid electrolyte abnormality, GI hemorrhage, intussusception, renal symptoms, and GI symptoms. The annual hospitalization rates for IgA vasculitis are declining in the USA across multiple age groups. GI and renal manifestations are associated with increased length of hospital stay.

  9. Occurrence and Evolution of the Paralogous Zinc Metalloproteases IgA1 Protease, ZmpB, ZmpC, and ZmpD in Streptococcus pneumoniae and Related Commensal Species

    PubMed Central

    Bek-Thomsen, Malene; Poulsen, Knud; Kilian, Mogens

    2012-01-01

    ABSTRACT The distribution, genome location, and evolution of the four paralogous zinc metalloproteases, IgA1 protease, ZmpB, ZmpC, and ZmpD, in Streptococcus pneumoniae and related commensal species were studied by in silico analysis of whole genomes and by activity screening of 154 representatives of 20 species. ZmpB was ubiquitous in the Mitis and Salivarius groups of the genus Streptococcus and in the genera Gemella and Granulicatella, with the exception of a fragmented gene in Streptococcus thermophilus, the only species with a nonhuman habitat. IgA1 protease activity was observed in all members of S. pneumoniae, S. pseudopneumoniae, S. oralis, S. sanguinis, and Gemella haemolysans, was variably present in S. mitis and S. infantis, and absent in S. gordonii, S. parasanguinis, S. cristatus, S. oligofermentans, S. australis, S. peroris, and S. suis. Phylogenetic analysis of 297 zmp sequences and representative housekeeping genes provided evidence for an unprecedented selection for genetic diversification of the iga, zmpB, and zmpD genes in S. pneumoniae and evidence of very frequent intraspecies transfer of entire genes and combination of genes. Presumably due to their adaptation to a commensal lifestyle, largely unaffected by adaptive mucosal immune factors, the corresponding genes in commensal streptococci have remained conserved. The widespread distribution and significant sequence diversity indicate an ancient origin of the zinc metalloproteases predating the emergence of the humanoid species. zmpB, which appears to be the ancestral gene, subsequently duplicated and successfully diversified into distinct functions, is likely to serve an important but yet unknown housekeeping function associated with the human host. PMID:23033471

  10. Self perceived work related stress and the relation with salivary IgA and lysozyme among emergency department nurses

    PubMed Central

    Yang, Y; Koh, D; Ng, V; Lee, C; Chan, G; Dong, F; Goh, S; Anantharaman, V; Chia, S

    2002-01-01

    Aims: To assess and compare the self perceived work related stress among emergency department (ED) and general ward (GW) nurses, and to investigate its relation with salivary IgA and lysozyme. Methods: One hundred and thirty two of 208 (63.5%) registered female ED and GW nurses participated in the study. A modified mental health professional stress scale (PSS) was used to measure self perceived stress. ELISA methods were used to determine the salivary IgA and lysozyme levels. Results: On PSS, ED nurses had higher scores (mean 1.51) than GW nurses (1.30). The scores of PSS subscales such as organisational structure and processes (OS), lack of resources (RES), and conflict with other professionals (COF) were higher in ED than in GW nurses. ED nurses had lower secretion rates of IgA (geometric mean (GM) 49.1 µg/min) and lysozyme (GM 20.0 µg/min) than GW nurses (68.2 µg/min, 30.5 µg/min). Significant correlations were observed between PSS and log IgA and lysozyme secretion rates. OS, RES, and COF were correlated with log IgA and lysozyme levels. Conclusion: ED nurses, who reported a higher level of professional stress, showed significantly lower secretion rates of salivary IgA and lysozyme compared to GW nurses. Salivary IgA and lysozyme were inversely correlated with self perceived work related stress. As these salivary biomarkers are reflective of the mucosal immunity, results support the inverse relation between stress and mucosal immunity. PMID:12468751

  11. The HIV-1 gp41 ectodomain is cleaved by matriptase to produce a chemotactic peptide that acts through FPR2

    PubMed Central

    Wood, Matthew P; Cole, Amy L; Eade, Colleen R; Chen, Li-Mei; Chai, Karl X; Cole, Alexander M

    2014-01-01

    Several aspects of HIV-1 virulence and pathogenesis are mediated by the envelope protein gp41. Additionally, peptides derived from the gp41 ectodomain have been shown to induce chemotaxis in monocytes and neutrophils. Whereas this chemotactic activity has been reported, it is not known how these peptides could be produced under biological conditions. The heptad repeat 1 (HR1) region of gp41 is exposed to the extracellular environment and could therefore be susceptible to proteolytic processing into smaller peptides. Matriptase is a serine protease expressed at the surface of most epithelia, including the prostate and mucosal surfaces. Here, we present evidence that matriptase efficiently cleaves the HR1 portion of gp41 into a 22-residue chemotactic peptide MAT-1, the sequence of which is highly conserved across HIV-1 clades. We found that MAT-1 induced migration of primary neutrophils and monocytes, the latter of which act as a cellular reservoir of HIV during early stage infection. We then used formyl peptide receptor 1 (FPR1) and FPR2 inhibitors, along with HEK 293 cells, to demonstrate that MAT-1 can induce chemotaxis specifically using FPR2, a receptor found on the surface of monocytes, macrophages and neutrophils. These findings are the first to identify a proteolytic cleavage product of gp41 with chemotactic activity and highlight a potential role for matriptase in HIV-1 transmission and infection at epithelial surfaces and within tissue reservoirs of HIV-1. PMID:24617769

  12. Complement factor H-related proteins in IgA nephropathy-sometimes a gentle nudge does the trick.

    PubMed

    Thurman, Joshua M; Laskowski, Jennifer

    2017-10-01

    Complement activation probably contributes to glomerular inflammation and damage in IgA nephropathy. In this issue, 2 groups report that levels of factor H-related protein 1 are elevated in patients with IgA nephropathy and correlate with disease progression. These studies provide new evidence that the complement cascade is important to the pathogenesis of this disease. These results also suggest that factor H-related protein 1 levels may be useful for identifying those patients at high risk of disease progression. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  13. Microbial ecology perturbation in human IgA deficiency.

    PubMed

    Fadlallah, Jehane; El Kafsi, Hela; Sterlin, Delphine; Juste, Catherine; Parizot, Christophe; Dorgham, Karim; Autaa, Gaëlle; Gouas, Doriane; Almeida, Mathieu; Lepage, Patricia; Pons, Nicolas; Le Chatelier, Emmanuelle; Levenez, Florence; Kennedy, Sean; Galleron, Nathalie; de Barros, Jean-Paul Pais; Malphettes, Marion; Galicier, Lionel; Boutboul, David; Mathian, Alexis; Miyara, Makoto; Oksenhendler, Eric; Amoura, Zahir; Doré, Joel; Fieschi, Claire; Ehrlich, S Dusko; Larsen, Martin; Gorochov, Guy

    2018-05-02

    Paradoxically, loss of immunoglobulin A (IgA), one of the most abundant antibodies, does not irrevocably lead to severe infections in humans but rather is associated with relatively mild respiratory infections, atopy, and autoimmunity. IgA might therefore also play covert roles, not uniquely associated with control of pathogens. We show that human IgA deficiency is not associated with massive quantitative perturbations of gut microbial ecology. Metagenomic analysis highlights an expected pathobiont expansion but a less expected depletion in some typically beneficial symbionts. Gut colonization by species usually present in the oropharynx is also reminiscent of spatial microbiota disorganization. IgM only partially rescues IgA deficiency because not all typical IgA targets are efficiently bound by IgM in the intestinal lumen. Together, IgA appears to play a nonredundant role at the forefront of the immune/microbial interface, away from the intestinal barrier, ranging from pathobiont control and regulation of systemic inflammation to preservation of commensal diversity and community networks. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  14. IgA and neutralizing antibodies to influenza a virus in human milk: a randomized trial of antenatal influenza immunization.

    PubMed

    Schlaudecker, Elizabeth P; Steinhoff, Mark C; Omer, Saad B; McNeal, Monica M; Roy, Eliza; Arifeen, Shams E; Dodd, Caitlin N; Raqib, Rubhana; Breiman, Robert F; Zaman, K

    2013-01-01

    Antenatal immunization of mothers with influenza vaccine increases serum antibodies and reduces the rates of influenza illness in mothers and their infants. We report the effect of antenatal immunization on the levels of specific anti-influenza IgA levels in human breast milk. (ClinicalTrials.gov identifier NCT00142389; http://clinicaltrials.gov/ct2/show/NCT00142389). The Mother's Gift study was a prospective, blinded, randomized controlled trial that assigned 340 pregnant Bangladeshi mothers to receive either trivalent inactivated influenza vaccine, or 23-valent pneumococcal polysaccharide vaccine during the third trimester. We evaluated breast milk at birth, 6 weeks, 6 months, and 12 months, and serum at 10 weeks and 12 months. Milk and serum specimens from 57 subjects were assayed for specific IgA antibody to influenza A/New Caledonia (H1N1) using an enzyme-linked immunosorbent assay (ELISA) and a virus neutralization assay, and for total IgA using ELISA. Influenza-specific IgA levels in breast milk were significantly higher in influenza vaccinees than in pneumococcal controls for at least 6 months postpartum (p = 0.04). Geometric mean concentrations ranged from 8.0 to 91.1 ELISA units/ml in vaccinees, versus 2.3 to 13.7 ELISA units/mL in controls. Virus neutralization titers in milk were 1.2 to 3 fold greater in vaccinees, and correlated with influenza-specific IgA levels (r = 0.86). Greater exclusivity of breastfeeding in the first 6 months of life significantly decreased the expected number of respiratory illness with fever episodes in infants of influenza-vaccinated mothers (p = 0.0042) but not in infants of pneumococcal-vaccinated mothers (p = 0.4154). The sustained high levels of actively produced anti-influenza IgA in breast milk and the decreased infant episodes of respiratory illness with fever suggest that breastfeeding may provide local mucosal protection for the infant for at least 6 months. Studies are needed to determine the

  15. Natural polyreactive IgA antibodies coat the intestinal microbiota

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bunker, Jeffrey J.; Erickson, Steven A.; Flynn, Theodore M.

    Large quantities of immunoglobulin A (IgA) are constitutively secreted by intestinal plasma cells to coat and contain the commensal microbiota, yet the specificity of these antibodies remains elusive. In this paper, we profiled the reactivities of single murine IgA plasma cells by cloning and characterizing large numbers of monoclonal antibodies. IgAs were not specific to individual bacterial taxa but rather polyreactive, with broad reactivity to a diverse, but defined, subset of microbiota. These antibodies arose at low frequencies among naïve B cells and were selected into the IgA repertoire upon recirculation in Peyer’s patches. This selection process occurred independent ofmore » microbiota or dietary antigens. Furthermore, although some IgAs acquired somatic mutations, these did not substantially influence their reactivity. In conclusion, these findings reveal an endogenous mechanism driving homeostatic production of polyreactive IgAs with innate specificity to microbiota.« less

  16. Natural polyreactive IgA antibodies coat the intestinal microbiota

    DOE PAGES

    Bunker, Jeffrey J.; Erickson, Steven A.; Flynn, Theodore M.; ...

    2017-09-28

    Large quantities of immunoglobulin A (IgA) are constitutively secreted by intestinal plasma cells to coat and contain the commensal microbiota, yet the specificity of these antibodies remains elusive. In this paper, we profiled the reactivities of single murine IgA plasma cells by cloning and characterizing large numbers of monoclonal antibodies. IgAs were not specific to individual bacterial taxa but rather polyreactive, with broad reactivity to a diverse, but defined, subset of microbiota. These antibodies arose at low frequencies among naïve B cells and were selected into the IgA repertoire upon recirculation in Peyer’s patches. This selection process occurred independent ofmore » microbiota or dietary antigens. Furthermore, although some IgAs acquired somatic mutations, these did not substantially influence their reactivity. In conclusion, these findings reveal an endogenous mechanism driving homeostatic production of polyreactive IgAs with innate specificity to microbiota.« less

  17. Fine Mapping Implicates a Deletion of CFHR1 and CFHR3 in Protection from IgA Nephropathy in Han Chinese

    PubMed Central

    Xie, Jingyuan; Kiryluk, Krzysztof; Li, Yifu; Mladkova, Nikol; Zhu, Li; Hou, Ping; Ren, Hong; Wang, Weiming; Zhang, Hong; Chen, Nan

    2016-01-01

    An intronic variant at the complement factor H (CFH) gene on chromosome 1q32 (rs6677604) associates with risk of IgA nephropathy (IgAN), but the association signal has not been uniformly replicated in Han Chinese populations. We investigated whether the causal sequence variant resides in the CFH gene or the neighboring complement factor H–related 1 (CFHR1) gene and CFHR3, which harbor an 84-kb combined deletion (CFHR3,1Δ) in linkage disequilibrium with rs6677604. Imputation of 1000 Genomes Project data did not suggest new causal single–nucleotide variants within the CFH cluster. We next performed copy number analysis across the CFH locus in two independent Han Chinese case-control cohorts (combined n=3581). The CFHR3,1Δ and rs6677604-A alleles were rare (4.4% in patients and 7.1% in controls) and in strong linkage disequilibrium with each other (r2=0.95); of these alleles, CFHR3,1Δ associated more significantly with decreased risk of IgAN (odds ratio [OR], 0.56; 95% confidence interval [95% CI], 0.46 to 0.70; P=8.5 × 10−8 versus OR, 0.61; 95% CI, 0.50 to 0.75; P=1.6 × 10−6 for rs6677604-A). Moreover, CFHR3,1Δ explained all of the association signal at rs6677604 and remained significant after conditioning on rs6677604 genotype (P=0.01). Exploratory analyses of clinical and histopathologic parameters using the Oxford classification criteria revealed a suggestive association of CFHR3,1Δ with reduced tubulointerstitial injury (OR, 0.46; 95% CI, 0.25 to 0.79). These data indicate that dysregulated activity of the alternative complement pathway contributes to IgAN pathogenesis in both Asians and Europeans and implicate CFHR3,1Δ as the functional allele at this locus. PMID:26940089

  18. Evaluation of salivary glucose, IgA and flow rate in diabetic patients: a case-control study.

    PubMed

    Bakianian Vaziri, P; Vahedi, M; Mortazavi, H; Abdollahzadeh, Sh; Hajilooi, M

    2010-01-01

    An association between diabetes mellitus and alterations in the oral cavity has been noted. In this study, we evaluated differences between salivary IgA, glucose and flow rate in diabetic patients compared with healthy controls. Forty patients with type 1 diabetes, 40 patients with type 2 diabetes and 40 healthy controls were selected. Whole unstimulated saliva samples were collected by the standard method and the salivary flow rate was determined. Nephelometric and Pars method were used to measure salivary IgA and salivary glucose concentrations, respectively. Statistical analysis was performed by Chi-square and t test. There were no significant differences in salivary IgA and glucose concentrations between type 1 and type 2 diabetic patients and their matched control subjects (P>0.05). Salivary flow rate was significantly lower in diabetic patients (P<0.05). In addition, DMFT was higher in diabetic patients than the controls. Determination of salivary constituents may be useful in the description and management of oral findings in diabetic patients.

  19. IgA antibodies against endomysium and transglutaminase: a comparison of methods.

    PubMed

    Jaskowski, T D; Schroder, C; Martins, T B; Litwin, C M; Hill, H R

    2001-01-01

    Recently, the endomysial antigen has been identified as the protein cross-linking enzyme known as tissue transglutaminase (tTG). Our objective was to compare a novel enzyme immunoassay (EIA) that detects IgA antibody against tTG to two standard IFA methods utilizing thin tissue sections of rat kidney/rat stomach (KS) and distal primate esophagus (PE) as substrates to detect IgA antibody against endomysium (EMA). Sera from 100 patients suspected of having gluten-sensitive enteropathy (GSE) and 23 sera possessing various antibodies used for EIA cross-reactivity studies were included. Additional tests, performed routinely in our laboratory, were utilized to further assess sera from patients suspected having GSE. These tests include anti-gliadin IgA antibody (AGA) and anti-reticulin IgA antibody (ARA) and are part of the European Society for Pediatric Gastroenterology and Nutrition (ESPGAN) revised criteria for diagnosing GSE. When compared to IFA using KS, the tTG EIA had a sensitivity of 87.5%, was 97.1% specific, and had an overall agreement of 94.0%. When compared to IFA using PE, the tTG EIA had a sensitivity of 92.6%, was 93.2% specific, and had an overall agreement of 93.0%. When the KS IFA was compared to the PE IFA for EMA, the KS IFA had a sensitivity of 96.3%, was 91.8% specific, and had an overall agreement of 93.0%. The majority of sera that were positive for tTG but were negative by IFA (KS, n = 2/PE, n = 5) possessed IgA antibodies against gliadin and/or reticulin. Five of six sera with negative results by PE IFA were positive by the KS IFA and possessed one or more antibodies to tTG and/or gliadin and/or reticulin. We conclude that the tTG EIA compares well to both KS and PE IFAs when detecting IgA antibody against endomysium. We do not recommend the use of PE to detect EMA primarily because of the inconsistencies (i.e., tissue selection, quality, and preparation) and limited availability of commercially prepared PE tissue.

  20. Anti-actin IgA antibodies in severe coeliac disease

    PubMed Central

    Granito, A; Muratori, P; Cassani, F; Pappas, G; Muratori, L; Agostinelli, D; Veronesi, L; Bortolotti, R; Petrolini, N; Bianchi, F B; Volta, U

    2004-01-01

    Anti-actin IgA antibodies have been found in sera of coeliacs. Our aim was to define the prevalence and clinical significance of anti-actin IgA in coeliacs before and after gluten withdrawal. One hundred and two biopsy-proven coeliacs, 95 disease controls and 50 blood donors were studied. Anti-actin IgA were evaluated by different methods: (a) antimicrofilament positivity on HEp-2 cells and on cultured fibroblasts by immunofluorescence; (b) anti-actin positivity by enzyme-linked immuosorbent assay (ELISA); and (c) presence of the tubular/glomerular pattern of anti-smooth muscle antibodies on rat kidney sections by immunofluorescence. Antimicrofilament IgA were present in 27% of coeliacs and in none of the controls. Antimicrofilament antibodies were found in 25 of 54 (46%) coeliacs with severe villous atrophy and in three of 48 (6%) with mild damage (P < 0·0001). In the 20 patients tested, antimicrofilaments IgA disappeared after gluten withdrawal in accordance with histological recovery. Our study shows a significant correlation between antimicrofilament IgA and the severity of intestinal damage in untreated coeliacs. The disappearance of antimicrofilament IgA after gluten withdrawal predicts the normalization of intestinal mucosa and could be considered a useful tool in the follow-up of severe coeliac disease. PMID:15270857

  1. Scarcity of autoreactive human blood IgA+ memory B cells

    PubMed Central

    Prigent, Julie; Lorin, Valérie; Kök, Ayrin; Hieu, Thierry; Bourgeau, Salomé

    2016-01-01

    Class‐switched memory B cells are key components of the “reactive” humoral immunity, which ensures a fast and massive secretion of high‐affinity antigen‐specific antibodies upon antigenic challenge. In humans, IgA class‐switched (IgA+) memory B cells and IgA antibodies are abundant in the blood. Although circulating IgA+ memory B cells and their corresponding secreted immunoglobulins likely possess major protective and/or regulatory immune roles, little is known about their specificity and function. Here, we show that IgA+ and IgG+ memory B‐cell antibodies cloned from the same healthy humans share common immunoglobulin gene features. IgA and IgG memory antibodies have comparable lack of reactivity to vaccines, common mucosa‐tropic viruses and commensal bacteria. However, the IgA+ memory B‐cell compartment contains fewer polyreactive clones and importantly, only rare self‐reactive clones compared to IgG+ memory B cells. Self‐reactivity of IgAs is acquired following B‐cell affinity maturation but not antibody class switching. Together, our data suggest the existence of different regulatory mechanisms for removing autoreactive clones from the IgG+ and IgA+ memory B‐cell repertoires, and/or different maturation pathways potentially reflecting the distinct nature and localization of the cognate antigens recognized by individual B‐cell populations. PMID:27469325

  2. A Comprehensive Genetic Study of Streptococcal Immunoglobulin A1 Proteases: Evidence for Recombination within and between Species

    PubMed Central

    Poulsen, Knud; Reinholdt, Jesper; Jespersgaard, Christina; Boye, Kit; Brown, Thomas A.; Hauge, Majbritt; Kilian, Mogens

    1998-01-01

    An analysis of 13 immunoglobulin A1 (IgA1) protease genes (iga) of strains of Streptococcus pneumoniae, Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguis was carried out to obtain information on the structure, polymorphism, and phylogeny of this specific protease, which enables bacteria to evade functions of the predominant Ig isotype on mucosal surfaces. The analysis included cloning and sequencing of iga genes from S. oralis and S. mitis biovar 1, sequencing of an additional seven iga genes from S. sanguis biovars 1 through 4, and restriction fragment length polymorphism (RFLP) analyses of iga genes of another 10 strains of S. mitis biovar 1 and 6 strains of S. oralis. All 13 genes sequenced had the potential of encoding proteins with molecular masses of approximately 200 kDa containing the sequence motif HEMTH and an E residue 20 amino acids downstream, which are characteristic of Zn metalloproteinases. In addition, all had a typical gram-positive cell wall anchor motif, LPNTG, which, in contrast to such motifs in other known streptococcal and staphylococcal proteins, was located in their N-terminal parts. Repeat structures showing variation in number and sequence were present in all strains and may be of relevance to the immunogenicities of the enzymes. Protease activities in cultures of the streptococcal strains were associated with species of different molecular masses ranging from 130 to 200 kDa, suggesting posttranslational processing possibly as a result of autoproteolysis at post-proline peptide bonds in the N-terminal parts of the molecules. Comparison of deduced amino acid sequences revealed a 94% similarity between S. oralis and S. mitis IgA1 proteases and a 75 to 79% similarity between IgA1 proteases of these species and those of S. pneumoniae and S. sanguis, respectively. Combined with the results of RFLP analyses using different iga gene fragments as probes, the results of nucleotide sequence comparisons provide evidence of

  3. Assessment of the value of detecting specific IgA antibodies for the diagnosis of a recently acquired primary Toxoplasma infection.

    PubMed

    Nascimento, Fernanda Santos; Suzuki, Lisandra Akemi; Rossi, Cláudio Lúcio

    2008-08-01

    To assess the value of detecting IgA antibodies for the diagnosis of a recently acquired primary Toxoplasma infection. IgA antibodies were screened in sera from 87 women with different serological profiles of Toxoplasma gondii IgM and IgG antibodies and Toxoplasma-specific IgG avidity. The IgM and IgG antibodies and the IgG avidity were measured with an automated Vitek Immuno Diagnostic Assay System (VIDAS). Anti-T.gondii IgA was measured with Platelia Toxo IgA TMB kits. All 12 sera obtained from women with clinical and/or serological evidence of a recently acquired Toxoplasma infection were positive for IgA. In 42 serum samples obtained more than 6 months after T. gondii infection from women with no clinical evidence of infection, but who had a positive IgM test and a high IgG avidity index, the IgA-enzyme linked immunosorbent assay (ELISA) test results were positive, negative, and doubtful in 16 (38.1%), 23 (54.8%), and 3 (7.1%) sera, respectively. In eight women, IgA was detected in sera collected more than 9 months after the onset of infection. The IgA test result was also positive in 11 of 12 sera (91.7%) obtained from women with no clinical evidence of toxoplasmosis, but who had a positive IgM test and a borderline IgG avidity index. The IgA-ELISA was negative in 21 sera obtained more than 2 years after the onset of T. gondii infection from women with no clinical evidence of toxoplasmosis, but who had a negative IgM test and a positive IgG test. These results show that IgA is not a dependable marker for a recently acquired primary Toxoplasma infection. Copyright (c) 2008 John Wiley & Sons, Ltd.

  4. Linear IgA bullous dermatosis in a neonate.

    PubMed

    Hruza, L L; Mallory, S B; Fitzgibbons, J; Mallory, G B

    1993-06-01

    A newborn black boy had two facial blisters at birth that progressed to bullous lesions over the trunk, genitals, extremities, and oral and tracheal mucosa. A biopsy specimen demonstrated a subepidermal bulla with mixed eosinophilic and neutrophilic, inflammatory infiltrate. Direct immunofluorescence showed linear IgA, IgG, and C3 depositions along the basement membrane zone, consistent with a diagnosis of childhood linear IgA bullous dermatosis (chronic bullous dermatosis of childhood). The skin disease was controlled with combined prednisone and dapsone. This is the youngest reported patient with the disease. Linear IgA bullous dermatosis should be considered in the differential diagnosis of blistering diseases of the newborn, and immunofluorescence should be performed on a skin biopsy specimen.

  5. Predominate HIV1-specific IgG activity in various mucosal compartments of HIV1-infected individuals.

    PubMed

    Lü, F X

    2000-10-01

    Evaluating mucosal humoral immunity is important for understanding local immunity induced by HIV infection or vaccination and designing prophylactic strategies. To characterize the mucosal humoral immunity following HIV infection, the levels of immunoglobulins (Igs), antibodies (Abs), and HIV1-specific Ab activity were evaluated in cervicovaginal secretions (CVS), saliva, breast milk, and sera of HIV-infected individuals. HIV1-specific IgG activity was significantly higher than that of IgA in CVS, saliva, and breast milk. The highest HIV1-specific IgG activity was found in breast milk. The data suggest that anti-HIV1 Abs in CVS were most likely serum derived. However, HIV1-specific Abs in saliva and breast milk were mainly locally produced. The prevalence of HIV1-specific Abs in seropositive subjects was 97% for IgG and 95% for IgA in CVS, 100% for IgG and 80% for IgA in saliva, and 59% for IgG and 94% for IgA in breast milk. These data provide evidence for both a better understanding of the nature of humoral mucosal responses after HIV1 infection and the development of strategies to induce desirable functional mucosal immunity for preventing HIV transmission. Copyright 2000 Academic Press.

  6. A rare case of Addison's disease, hepatitis, thyreoiditis, positive IgG anti-tissue transglutaminase antibodies and partial IgA deficiency.

    PubMed

    Baleva, Marta P; Mihaylova, Snejina; Yankova, Petja; Atanasova, Iliana; Nikolova-Vlahova, Milena; Naumova, Elissaveta

    2016-01-01

    Selective IgA deficiency (IgAD) is the most prevalent type of primary immune deficiencies, but partial IgA deficiency is even more common. Addison's disease is a rare condition associated with primary adrenal insufficiency due to infection or autoimmune destruction of the adrenals. The association between IgA deficiency and Addison's disease is very rare. We observed a 22-year-old male patient with marked darkening of the skin, especially on the palms and areolae, jaundice on the skin and sclera, astheno-adynamia, hypotension (80/50 mm Hg), and pain in the right hypochondrium. The laboratory investigations revealed increased serum levels of total and indirect bilirubin, AST, ALT, GGT and LDH, negative HBsAg, anti-HBc IgM, anti-HCV and anti-HAV IgM, very low serum IgA levels (0.16 g/l) with normal IgG and IgM, negative ANA, ANCA, AMA, LKM-1, anti-GAD-60, anti-IA-2, anti-thyroglobulin antibodies, a mild increase in anti-TPO antibodies titer, a marked increase in IgG anti-tissue transglutaminase antibodies, with no typical changes in cellular immunity, negative T-SPOT-TB test, HLA - A*01; B*08; DRB1*03; DQB1*02, karyotype - 46, XY. We present a rare case of partial IgA deficiency with Addison's disease, hepatitis, thyroiditis and positive anti-tissue transglutaminase antibodies. IgAD and some autoimmune disorders share several predisposing HLA genes, thus explaining the increased prevalence of IgAD in certain patient groups.

  7. Detection of IgA-class circulating immune complexes (CIC) in sera from patients with IgA nephropathy using a solid-phase anti-C3 Facb enzyme immunoassay (EIA).

    PubMed Central

    Yagame, M; Tomino, Y; Miura, M; Tanigaki, T; Suga, T; Nomoto, Y; Sakai, H

    1987-01-01

    The detection of circulating immune complexes (CIC) in sera from patients with IgA nephropathy is described. A solid-phase anti-C3 Facb enzyme immunoassay (EIA) was employed for detection of IgA-, IgG- and IgM-CIC in sera. The C1q-binding enzyme assay was also used for the detection of CIC in sera from these patients and healthy adults. Twenty-two patients with IgA nephropathy, 14 patients with other glomerular diseases and 19 healthy adults were examined by anti-C3 Facb EIA. The levels of IgA-CIC in sera from patients with IgA nephropathy were significantly higher than those in sera from patients with other glomerular diseases and healthy adults. CIC measured by the C1q-binding enzyme assay was detected in some patients with IgA nephropathy. The levels of serum IgA in patients with IgA nephropathy were significantly higher than those in patients with other glomerular diseases and healthy adults. However, there was no significant correlation between the levels of IgA-CIC in sera and those of serum IgA in patients with IgA nephropathy. There was also no significant correlation between the levels of IgA-CIC in sera and the degree of histopathological injuries in the patients. It is concluded that the solid-phase anti-C3 Facb EIA is useful for the detection of IgA-CIC in sera from patients with IgA nephropathy. PMID:3301093

  8. A new fluorogenic small molecule labeling tool for surface diffusion analysis and advanced fluorescence imaging of β-site amyloid precursor protein (APP)-cleaving enzyme 1 based on silicone rhodamine: SiR-BACE1.

    PubMed

    Karch, Sandra; Broichhagen, Johannes; Schneider, Julia; Böning, Daniel; Hartmann, Stephanie; Schmid, Benjamin; Tripal, Philipp; Palmisano, Ralf; Alzheimer, Christian; Johnsson, Kai; Huth, Tobias

    2018-06-25

    β-site APP-cleaving enzyme 1 (BACE1) is a major player in the pathogenesis of Alzheimer's disease. Structural and functional fluorescence microscopy offers a powerful approach to learn about the physiology and pathophysiology of this protease. Up to now, however, common labeling techniques either require genetic manipulation, use large antibodies, or are not compatible with live cell imaging. Fluorescent small molecules that specifically bind to the protein of interest can overcome these limitations. Herein, we introduce SiR-BACE1, a conjugate of the BACE1 inhibitor S-39 and SiR647, as a novel fluorogenic, tag-free, and antibody-free label for BACE1. We present its chemical development, characterize its photo-physical and pharmacologic properties, and evaluate its behavior in solution, in over-expression systems, and in native brain tissue. We demonstrate its applicability in confocal, stimulated emission depletion (STED), and dynamic single molecule microscopy. First functional studies with SiR-BACE1 on the surface mobility of BACE1 revealed a markedly confined diffusion pattern.

  9. IgA antibasement membrane nephritis with pulmonary hemorrhage.

    PubMed

    Border, W A; Baehler, R W; Bhathena, D; Glassock, R J

    1979-07-01

    Goodpasture's syndrome has characteristically been described as being mediated by IgG antibodies. We have recently seen a 55-year-old man who developed renal failure and hemoptysis; a renal biopsy showed linear deposits of IgA and C3 involving glomerular and tubular basement membrane. Serologic tests for detecting (IgG) antiglomerular basement membrane antibodies were negative. Elution studies of kidney and lung showed the presence of an IgA antibasement membrane antibody only. The patient's serum contained IgA, but not IgG, antibodies reactive with glomerular and tubular basement membrane of normal human kidney and alveolar basement membrane of normal human lung. Attempts to transfer disease with the patient's IgA antibody to a monkey and to Lewis and Brown-Norway rats were unsuccessful. Immunoglobulin A antibasement membrane antibody must be considered in the design of immunoserologic procedures for the diagnosis of Goodpasture's syndrome.

  10. PetIGA: A framework for high-performance isogeometric analysis

    DOE PAGES

    Dalcin, Lisandro; Collier, Nathaniel; Vignal, Philippe; ...

    2016-05-25

    We present PetIGA, a code framework to approximate the solution of partial differential equations using isogeometric analysis. PetIGA can be used to assemble matrices and vectors which come from a Galerkin weak form, discretized with Non-Uniform Rational B-spline basis functions. We base our framework on PETSc, a high-performance library for the scalable solution of partial differential equations, which simplifies the development of large-scale scientific codes, provides a rich environment for prototyping, and separates parallelism from algorithm choice. We describe the implementation of PetIGA, and exemplify its use by solving a model nonlinear problem. To illustrate the robustness and flexibility ofmore » PetIGA, we solve some challenging nonlinear partial differential equations that include problems in both solid and fluid mechanics. Lastly, we show strong scaling results on up to 4096 cores, which confirm the suitability of PetIGA for large scale simulations.« less

  11. Human dipeptidyl peptidase III acts as a post-proline-cleaving enzyme on endomorphins.

    PubMed

    Barsun, Marina; Jajcanin, Nina; Vukelić, Bojana; Spoljarić, Jasminka; Abramić, Marija

    2007-03-01

    Dipeptidyl peptidase III (DPP III) is a zinc exopeptidase with an implied role in the mammalian pain-modulatory system owing to its high affinity for enkephalins and localisation in the superficial laminae of the spinal cord dorsal horn. Our study revealed that this human enzyme hydrolyses opioid peptides belonging to three new groups, endomorphins, hemorphins and exorphins. The enzymatic hydrolysis products of endomorphin-1 were separated and quantified by capillary electrophoresis and the kinetic parameters were determined for human DPP III and rat DPP IV. Both peptidases cleave endomorphin-1 at comparable rates, with liberation of the N-terminal Tyr-Pro. This is the first evidence of DPP III acting as an endomorphin-cleaving enzyme.

  12. Acquisition of resistance toward HYD1 correlates with a reduction in cleaved α4 integrin expression and a compromised CAM-DR phenotype.

    PubMed

    Emmons, Michael F; Gebhard, Anthony W; Nair, Rajesh R; Baz, Rachid; McLaughlin, Mark L; Cress, Anne E; Hazlehurst, Lori A

    2011-12-01

    We recently reported that the β1 integrin antagonist, referred to as HYD1, induces necrotic cell death in myeloma cell lines as a single agent using in vitro and in vivo models. In this article, we sought to delineate the determinants of sensitivity and resistance toward HYD1-induced cell death. To this end, we developed an HYD1 isogenic resistant myeloma cell line by chronically exposing H929 myeloma cells to increasing concentrations of HYD1. Our data indicate that the acquisition of resistance toward HYD1 correlates with reduced levels of the cleaved α4 integrin subunit. Consistent with reduced VLA-4 (α4β1) expression, the resistant variant showed ablated functional binding to fibronectin, VCAM-1, and the bone marrow stroma cell line HS-5. The reduction in binding of the resistant cell line to HS-5 cells translated to a compromised cell adhesion-mediated drug resistant phenotype as shown by increased sensitivity to melphalan- and bortezomib-induced cell death in the bone marrow stroma coculture model of drug resistance. Importantly, we show that HYD1 is more potent in relapsed myeloma specimens than newly diagnosed patients, a finding that correlated with α4 integrin expression. Collectively, these data indicate that this novel d-amino acid peptide may represent a good candidate for pursuing clinical trials in relapsed myeloma and in particular patients with high levels of α4 integrin. Moreover, our data provide further rationale for continued preclinical development of HYD1 and analogues of HYD1 for the treatment of multiple myeloma and potentially other tumors that home and/or metastasize to the bone.

  13. Nucleotide cleaving agents and method

    DOEpatents

    Que, Jr., Lawrence; Hanson, Richard S.; Schnaith, Leah M. T.

    2000-01-01

    The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.

  14. Distribution of immunoglobulin G (IgG) and A (IgA) subclasses following Q fever vaccination with soluble phase I Coxiella burnetii extract.

    PubMed

    Camacho, M T; Outschoorn, I; Kovácová, E; Téllez, A

    2000-03-06

    High levels of IgG1, IgG3 and IgA2 antibodies have been observed in patients with Q fever following Coxiella burnetii infection. This IgG subclass distribution is more typical of viral and autoimmune diseases than of bacterial infections. It seemed, therefore, of interest to carry out a prospective study of the distribution of immunoglobulin subclasses after vaccination with phase I C. burnetii tricloroacetic soluble extracts to detect possible differences with respect to natural infection. The antibody response found in vaccinees was mainly restricted to the IgG1, IgG2 and IgA1 subclasses. These findings confirm differences in isotype distribution when compared to those of patients with acute or chronic Coxiella infections and opens an area of interest with respect to the role of IgA subclasses.

  15. Serum IgG and IgA levels in polio and non-polio acute flaccid paralysis cases in western Uttar Pradesh, India.

    PubMed

    Mohanty, Madhu C; Nalavade, Uma P; Deshpande, Jagadish M

    2015-03-08

    IgG and IgA immunocompetence of children with wild poliovirus poliomyelitis and non-polio acute flaccid paralysis. 932 cases of acute flaccid paralysis, reported in 2008-2009, were tested for presence of polio and non-polio enteroviruses according to the WHO standards. Serum IgA and IgG levels were determined by sandwich ELISA. Mean (SD) IgA levels [0.87 (0.62)g/L; n=28] of virologically confirmed poliomyelitis cases were lower than those of virus negative [1.21 (0.83)g/L; n=612] and non-polio Enterovirus positive [1.22 (0.79)g/L; n=240] cases of acute flaccid paralysis. No significant difference was observed in the concentration of IgG among these groups. IgA plays an important role in protection against poliomyelitis.

  16. A Novel Cryptic Binding Motif, LRSKSRSFQVSDEQY, in the C-Terminal Fragment of MMP-3/7-Cleaved Osteopontin as a Novel Ligand for α9β1 Integrin Is Involved in the Anti-Type II Collagen Antibody-Induced Arthritis

    PubMed Central

    Kon, Shigeyuki; Nakayama, Yosuke; Matsumoto, Naoki; Ito, Koyu; Kanayama, Masashi; Kimura, Chiemi; Kouro, Hitomi; Ashitomi, Dai; Matsuda, Tadashi; Uede, Toshimitsu

    2014-01-01

    Osteopontin (OPN) is a multifunctional protein that has been linked to various intractable inflammatory diseases. One way by which OPN induces inflammation is the production of various functional fragments by enzyme cleavage. It has been well appreciated that OPN is cleaved by thrombin, and/or matrix metalloproteinase-3 and -7 (MMP-3/7). Although the function of thrombin-cleaved OPN is well characterized, little is known about the function of MMP-3/7-cleaved OPN. In this study, we found a novel motif, LRSKSRSFQVSDEQY, in the C-terminal fragment of MMP-3/7-cleaved mouse OPN binds to α9β1 integrin. Importantly, this novel motif is involved in the development of anti-type II collagen antibody-induced arthritis (CAIA). This study provides the first in vitro and in vivo evidence that OPN cleavage by MMP-3/7 is an important regulatory mechanism for CAIA. PMID:25545242

  17. Development of the gut microbiota and mucosal IgA responses in twins and gnotobiotic mice

    PubMed Central

    Planer, Joseph D.; Peng, Yangqing; Kau, Andrew L.; Blanton, Laura V.; Ndao, I. Malick; Tarr, Phillip I.; Warner, Barbara B.; Gordon, Jeffrey I.

    2016-01-01

    Immunoglobulin A (IgA), the major class of antibody secreted by the gut mucosa, is an important contributor to gut barrier function1–3. The repertoire of IgA bound to gut bacteria reflects both T cell-dependent and -independent pathways4,5, plus glycans present on the antibody’s secretory component6. Human gut bacterial taxa targeted by IgA in the setting of intestinal barrier dysfunction are capable of producing intestinal pathology when isolated and transferred to gnotobiotic mice7,8. A complex reorientation of gut immunity occurs as infants transition from passively acquired IgA present in breast milk to host-derived IgA9–11. How IgA responses co-develop with assembly of the microbiota during this period remains poorly understood. Here, we (i) identify a set of age-discriminatory bacterial taxa whose representations define a program of microbiota assembly/maturation during the first 2 postnatal years that is shared across 40 healthy USA twin pairs; (ii) describe a pattern of progression of gut mucosal IgA responses to bacterial members of the microbiota that is highly distinctive for family members (twin pairs) during the first several postnatal months then generalizes across pairs in the second year; and (iii) assess the effects of zygosity, birth mode and breast feeding. Age-associated differences in these IgA responses can be recapitulated in young germ-free mice, colonized with fecal microbiota obtained from two twin pairs at 6 and 18 months of age, and fed a sequence of human diets that simulate the transition from milk feeding to complementary foods. The majority of these responses were robust to diet suggesting that ‘intrinsic’ properties of community members play a dominant role in dictating IgA responses. The approach described can be used to define gut mucosal immune development in health and disease states and help discover ways for repairing or preventing perturbations in this facet of host immunity. PMID:27279225

  18. Development of the gut microbiota and mucosal IgA responses in twins and gnotobiotic mice.

    PubMed

    Planer, Joseph D; Peng, Yangqing; Kau, Andrew L; Blanton, Laura V; Ndao, I Malick; Tarr, Phillip I; Warner, Barbara B; Gordon, Jeffrey I

    2016-06-09

    Immunoglobulin A (IgA), the major class of antibody secreted by the gut mucosa, is an important contributor to gut barrier function. The repertoire of IgA bound to gut bacteria reflects both T-cell-dependent and -independent pathways, plus glycans present on the antibody's secretory component. Human gut bacterial taxa targeted by IgA in the setting of barrier dysfunction are capable of producing intestinal pathology when isolated and transferred to gnotobiotic mice. A complex reorientation of gut immunity occurs as infants transition from passively acquired IgA present in breast milk to host-derived IgA. How IgA responses co-develop with assembly of the microbiota during this period remains poorly understood. Here, we (1) identify a set of age-discriminatory bacterial taxa whose representations define a program of microbiota assembly and maturation during the first 2 postnatal years that is shared across 40 healthy twin pairs in the USA; (2) describe a pattern of progression of gut mucosal IgA responses to bacterial members of the microbiota that is highly distinctive for family members (twin pairs) during the first several postnatal months then generalizes across pairs in the second year; and (3) assess the effects of zygosity, birth mode, and breast feeding. Age-associated differences in these IgA responses can be recapitulated in young germ-free mice, colonized with faecal microbiota obtained from two twin pairs at 6 and 18 months of age, and fed a sequence of human diets that simulate the transition from milk feeding to complementary foods. Most of these responses were robust to diet, suggesting that 'intrinsic' properties of community members play a dominant role in dictating IgA responses. The approach described can be used to define gut mucosal immune development in health and disease states and to help discover ways of repairing or preventing perturbations in this facet of host immunity.

  19. A complex structure in the mRNA of Tf1 is recognized and cleaved to generate the primer of reverse transcription.

    PubMed

    Lin, J H; Levin, H L

    1997-01-15

    All retroviruses and LTR-containing retrotransposons are thought to require specific tRNA molecules to serve as primers of reverse transcription. An exception is the LTR-containing retrotransposon Tf1, isolated from Schizosaccharomyces pombe. Instead of requiring a tRNA, the reverse transcriptase of Tf1 uses the first 11 bases of the Tf1 transcript as the primer for reverse transcription. The primer is generated by a cleavage that occurs between bases 11 and 12 of the Tf1 mRNA. Sequence analysis of the 5' untranslated region of the Tf1 mRNA resulted in the identification of a region with the potential to form an RNA structure of 89 bases that included the primer binding site and the first 11 bases of the Tf1 mRNA. Systematic mutagenesis of this region revealed 34 single-point mutants in the structure that resulted in reduced transposition activity. The defects in transposition correlated with reduced level of Tf1 reverse transcripts as determined by DNA blot analysis. Evidence that the RNA structure did form in vivo included the result that strains with second site mutations that restored complementarity resulted in increased levels of reverse transcripts and Tf1 transposition. The majority of the mutants defective for reverse transcription were unable to cleave the Tf1 mRNA between bases 11 and 12. These data indicate that formation of an extensive RNA structure was required for the cleavage reaction that generated the primer for Tf1 reverse transcription.

  20. Evaluation of seven assays detecting serum immunoglobulin classes and subclasses and salivary and faecal secretory IgA against Fasciola excretory/secretory (ES) antigens in diagnosing fascioliasis.

    PubMed

    Noureldin, Mohamed S; el-Ganaini, Goman A; Abou El-Enin, Ahmed M; el-Nemr, Hosam-Eldin I; Hussin, Eman M; Sultan, Doaa M

    2004-08-01

    Seven assays detecting serum IgM, IgG, IgG1, IgG4, IgA and salivary and fecal excretory IgA against Fasciola excretory/secretory (ES) antigens were evaluated in diagnosing fascioliasis, for cross reactivity with Schistosoma mansoni sera and for evaluation of cure of Fasciola infection after treatment. Assays detecting sera IgM, IgG1, IgG4 and IgA against Fasciola ES antigens showed 100% specificity and sensitivity. Assays detecting IgM and IgG showed 98% and 96% sensitivity and 100% and 94.6% specificity respectively. Assays detecting salivary and faecal IgA showed 92% & 96% sensitivity and 100% & 100% specificity respectively. Assays detecting IgM and IgG4 were the best in evaluation of cure and assays detecting IgG4 & IgA showed the lowest cross-reactivity with sera from S. mansoni infected patients. So, assays detecting serum IgA, IgG1 & IgG4 against Fasciola ES antigens were highly sensitive and specific for diagnosis of fascioliasis and assays detecting salivary and faecal IgA were promising and of great help in diagnosis of fascioliasis especially in epidemiologic studies.

  1. Gluten sensitivity in patients with IgA nephropathy.

    PubMed

    Smerud, Hilde Kloster; Fellström, Bengt; Hällgren, Roger; Osagie, Sonia; Venge, Per; Kristjánsson, Gudjón

    2009-08-01

    Coeliac disease is more frequent in IgA nephropathy (IgAN) patients compared to the healthy population. Several hypotheses postulate that food antigens like gluten may be involved in the onset of IgAN. In this study, we used a recently developed mucosal patch technique to evaluate the rectal mucosal inflammatory reaction to gluten in patients with IgAN (n = 27) compared to healthy subjects (n = 18). The rectal mucosal production of nitric oxide (NO) and release of myeloperoxidase (MPO) and eosinophil cationic protein (ECP) were measured. Serum samples were analysed for IgA and IgG antigliadin antibodies (AGA), IgA antibodies against tissue transglutaminase and IgA endomysium antibodies. Gluten reactivity, defined as increase in MPO and/or NO after gluten exposure, was observed in 8 of 27 IgAN patients. The prevalence of HLA-DQ2 and DQ8 was not increased among gluten-sensitive patients, and the total prevalence among IgAN patients was the same as for the normal population. An elevated serum IgA AGA response was seen in 9 of 27 IgAN patients. The increase in IgA AGA did not correlate with the gluten sensitivity as measured by NO and/or MPO. A specific serum IgG AGA response was seen in one patient only. Antibodies against tissue transglutaminase and endomysium were not observed. It is concluded that approximately one-third of our IgAN patients have a rectal mucosal sensitivity to gluten, but without signs of coeliac disease, and we hypothesize that such sub-clinical inflammation to gluten might be involved in the pathogenesis of IgAN in a subgroup of patients.

  2. Frequency of anti- Toxoplasma gondii IgA, IgM, and IgG antibodies in high-risk pregnancies, in Brazil.

    PubMed

    Murata, Fernando Henrique Antunes; Ferreira, Marina Neves; Camargo, Natália Sahyoun; Santos, Gabriela Soria; Spegiorin, Lígia Cosentino Junqueira Franco; Silveira-Carvalho, Aparecida Perpétuo; Pereira-Chioccola, Vera Lucia; Mattos, Luiz Carlos de; Mattos, Cinara Cássia Brandão de

    2016-01-01

    Toxoplasmosis during pregnancy can be severe; thus, it is essential to diagnose the disease via serological tests. An enzyme-linked immunosorbent assay (ELISA) was used to investigate anti-Toxoplasma gondii immunoglobulin A (IgA), M (IgM) and G (IgG) antibodies in 62 high-risk pregnant women. Forty-three (69.4%) women were positive for IgA, 31 (50%) for IgG, and 57 (91.9%) for IgM; 4 (6,5%) were positive for IgA but negative for IgM; 10 (16.1%) were negative for IgA and IgM but positive for IgG. Testing for these antibodies can help diagnose infection in pregnant women, thereby contributing to clinical management.

  3. Pre- and Posttransplant IgA Anti-Fab Antibodies to Predict Long-term Kidney Graft Survival.

    PubMed

    Amirzargar, M A; Amirzargar, A; Basiri, A; Hajilooi, M; Roshanaei, G; Rajabi, G; Solgi, G

    2015-05-01

    Immunologic factors are reliable markers for allograft monitoring, because of their seminal role in rejection process. One of these factors is the immunoglobulin (Ig)A anti-Fab of the IgG antibody. This study aimed to evaluate the predictive value of pre- and posttransplant levels of this marker for kidney allograft function and survival. Sera samples of 59 living unrelated donor kidney recipients were collected before and after transplantation (days 7, 14, and 30) and investigated for IgA anti-Fab of IgG antibody levels using enzyme-linked immunosorbent assay in relation with allograft outcome. Among 59 patients, 15 cases (25%) including 10 with acute rejection and 5 with chronic rejection episodes showed graft failure during a mean of 5 years of follow-up. High posttransplant levels of IgA anti-Fab antibodies were observed more frequently in patients with stable graft function (SGF) compared with patients with graft failure (P = 2 × 10(-6)). None of patients with acute or chronic rejection episodes had high levels of IgA anti-Fab antibodies at day 30 posttransplant compared with the SGF group (P = 10(-6) and P = .01, respectively). In addition, high levels of IgA anti-Fab antibody correlated with lesser concentration of serum creatinine at 1 month posttransplantation (P = .01). Five-year graft survival was associated with high levels of pre- and posttransplant IgA anti-Fab antibodies (P = .02 and P = .003, respectively). Our findings indicate the protective effect of higher levels of IgA anti-Fab antibodies regarding to kidney allograft outcomes and long-term graft survival. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Specific IgA and IgG antibodies in paired serum and breast milk samples in human strongyloidiasis.

    PubMed

    Mota-Ferreira, Daniela M L; Gonçalves-Pires, Maria do Rosário F; Júnior, Alvaro Ferreira; Sopelete, Mônica C; Abdallah, Vânia O S; Costa-Cruz, Julia M

    2009-02-01

    Strongyloidiasis, caused by the nematode Strongyloides stercoralis, is one of the major worldwide parasitic infections in humans. Breastfeeding may offer a potential protection against this infection. Feces, serum and milk samples were obtained from 90 lactating women from Clinical Hospital of Universidade Federal de Uberlândia, Brazil. The fecal samples were collected for parasitological diagnosis and the serum and milk samples were examined for specific S. stercoralis IgA and IgG antibodies using the indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA). Fecal examination showed that the rate of prevalence of S. stercoralis infection in the lactating women was 4.4%. IFAT manifested a 16.7% positivity rate for specific IgA antibody in serum and a 28.9% rate in milk samples; specific IgG was 41.1% in serum and 25.5% in milk samples. According to ELISA the positivity rate for specific IgA antibody was 21.1% in serum and 42.2% in milk samples; specific IgG was 40% in serum and 18.9% in milk samples. In serum samples, these immunological tests showed a concurrence of 91.1% and 94.4%, respectively, in detecting specific IgA and IgG antibodies. In milk samples, they showed a concurrence of 70% and 78.9%, respectively, in detecting specific IgA and IgG antibodies. There was a statistically significant difference between concordant and discordant results of immunological tests (P<0.0001). IFAT and ELISA highly concurred in their detection of specific S. stercoralis IgA and IgG antibodies in serum and in milk samples reconfirming prior studies that the serological method is a complement to the direct diagnosis of the parasite, and suggesting that immunological methods using milk samples can also be helpful. Furthermore, in endemic areas, infants may acquire antibodies to S. stercoralis from breast milk, possibly, contributing to the enhancement of specific mucosal immunity against this parasite.

  5. Breastfeeding linked to the reduction of both rotavirus shedding and IgA levels after Rotarix® immunization in Mexican infants.

    PubMed

    Bautista-Marquez, Aurora; Velasquez, Daniel E; Esparza-Aguilar, Marcelino; Luna-Cruz, Maria; Ruiz-Moran, Tatiana; Sugata, Ken; Jiang, Baoming; Parashar, Umesh; Patel, Manish; Richardson, Vesta

    2016-10-17

    We examined potential risk factors on vaccine virus shedding and antibody seroresponse to human rotavirus vaccine (Rotarix) in Mexican infants. Two doses of Rotarix were administered to infants during the first two visits for their routine childhood immunization (∼8 and 15weeks of age) in Mexico City. Infant's characteristics and socioeconomic indicators were obtained, including history of long-term feeding practices (exclusively/predominantly breastfed and exclusively/predominantly non-breastfed). Two serum specimens were collected, one during the second rotavirus vaccine visit and one 7weeks later. Stool specimens were collected between days 4-7 after each of the two rotavirus vaccine doses. Rotavirus IgA and IgG titers in serum were determined by enzyme immunoassays (EIA) and rotavirus shedding in stool was assessed by EIA and confirmed by RT-PCR. The overall rotavirus IgA geometric mean titers (GMT) increased significantly post dose 2 from post dose 1 [176 (95%CI: 113-273) to 335 (238-471); p=0.020). Infants who were exclusively/predominantly breastfed were less likely to shed vaccine virus in stool than those who were formula-fed (22% vs. 43%, p=0.016). Infants who were breastfed had lower rotavirus IgA titers than those who were formula-fed after dose 1 [GMT: 145 (84-250) vs. 267 (126-566) p=0.188] and dose 2 [236 (147-378) vs.578 (367-910), p=0.007]. Infants who shed vaccine virus post dose 1 had significantly higher serum IgA GMT than those who did not shed [425 (188-965) vs. 150 (84-266), p=0.038]. Breastfeeding was linked with the reduction of both stool vaccine shedding, and IgA seroresponse. The reduced rotavirus replication in the gut and shedding after dose 1 may explain in part the lower IgA response in serum. Published by Elsevier Ltd.

  6. Reformatting palivizumab and motavizumab from IgG to human IgA impairs their efficacy against RSV infection in vitro and in vivo.

    PubMed

    Jacobino, Shamir R; Nederend, Maaike; Reijneveld, J Frederiek; Augustijn, Daan; Jansen, J H Marco; Meeldijk, Jan; Reiding, Karli R; Wuhrer, Manfred; Coenjaerts, Frank E J; Hack, C Erik; Bont, Louis J; Leusen, Jeanette H W

    2018-04-01

    Respiratory syncytial virus (RSV) infection is a leading cause of hospitalization and mortality in young children. Protective therapy options are limited. Currently, palivizumab, a monoclonal IgG1 antibody, is the only licensed drug for RSV prophylaxis, although other IgG antibody candidates are being evaluated. However, at the respiratory mucosa, IgA antibodies are most abundant and act as the first line of defense against invading pathogens. Therefore, it would be logical to explore the potential of recombinant human IgA antibodies to protect against viral respiratory infection, but very little research on the topic has been published. Moreover, it is unknown whether human antibodies of the IgA isotype are better suited than those of the IgG isotype as antiviral drugs to combat respiratory infections. To address this, we generated various human IgA antibody formats of palivizumab and motavizumab, two well-characterized human IgG1 anti-RSV antibodies. We evaluated their efficacy to prevent RSV infection in vitro and in vivo and found similar, but somewhat decreased efficacy for different IgA subclasses and formats. Thus, reformatting palivizumab or motavizumab into IgA reduces the antiviral potency of either antibody. Moreover, our results indicate that the efficacy of intranasal IgA prophylaxis against RSV infection in human FcαRI transgenic mice is independent of Fc receptor expression.

  7. Evaluation of the Oxford Classification of IgA nephropathy: a systematic review and meta-analysis.

    PubMed

    Lv, Jicheng; Shi, Sufang; Xu, Damin; Zhang, Hong; Troyanov, Stéphan; Cattran, Daniel C; Wang, Haiyan

    2013-11-01

    The Oxford Classification of the pathology of immunoglobulin A (IgA) nephropathy, developed in 2009, is highly predictive of renal prognosis. It has been validated in different populations, but the results remain inconsistent. Systematic review and meta-analysis. Patients with biopsy-proven primary IgA nephropathy. Studies assessing the Oxford Classification of IgA nephropathy published between January 2009 and December 2012 were included following systematic searching of the MEDLINE and EMBASE databases. 4 pathologic lesions of the Oxford Classification: mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T). Kidney failure defined as doubled serum creatinine level, 50% decline in estimated glomerular filtration rate, or end-stage kidney disease. 16 retrospective cohort studies with 3,893 patients and 570 kidney failure events were included. In a multivariate model, HRs for kidney failure were 0.6 (95% CI, 0.5-0.8; P < 0.001), 1.8 (95% CI, 1.4-2.4; P < 0.001), and 3.2 (95% CI, 1.8-5.6; P < 0.001) for scores of M0 (mesangial hypercellularity score ≤0.5), S1 (presence of segmental glomerulosclerosis), and T1/2 (>25% tubular atrophy/interstitial fibrosis), respectively, without evidence of heterogeneity. Pooled results showed that E lesions were not associated with kidney failure (HR, 1.4; 95% CI, 0.9-2.0; P = 0.1), with evidence of heterogeneity (I(2) = 54.1%; P = 0.01). Crescent (C) lesions were associated with kidney failure (HR, 2.3; 95% CI, 1.6-3.4; P < 0.001), with no evidence of heterogeneity (I(2) = 14.7%; P = 0.3). All studies were retrospective. This was not an individual-patient-data meta-analysis. This study suggests that M, S, T, and C lesions, but not E lesions, are associated strongly with progression to kidney failure and thus should be included in the Oxford Classification system. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc

  8. Intermittent fasting promotes bacterial clearance and intestinal IgA production in Salmonella typhimurium-infected mice.

    PubMed

    Godínez-Victoria, M; Campos-Rodriguez, R; Rivera-Aguilar, V; Lara-Padilla, E; Pacheco-Yepez, J; Jarillo-Luna, R A; Drago-Serrano, M E

    2014-05-01

    The impact of intermittent fasting versus ad libitum feeding during Salmonella typhimurium infection was evaluated in terms of duodenum IgA levels, bacterial clearance and intestinal and extra-intestinal infection susceptibility. Mice that were intermittently fasted for 12 weeks or fed ad libitum were infected with S. typhimurium and assessed at 7 and 14 days post-infection. Next, we evaluated bacterial load in the faeces, Peyer's patches, spleen and liver by plate counting, as well as total and specific intestinal IgA and plasmatic corticosterone levels (by immunoenzymatic assay) and lamina propria IgA levels in plasma cells (by cytofluorometry). Polymeric immunoglobulin receptor, α- and J-chains, Pax-5 factor, pro-inflammatory cytokine (tumour necrosis factor-α and interferon-γ) and anti-inflammatory cytokine (transforming growth factor-β) mRNA levels were assessed in mucosal and liver samples (by real-time PCR). Compared with the infected ad libitum mice, the intermittently fasted infected animals had (1) lower intestinal and systemic bacterial loads; (2) higher SIgA and IgA plasma cell levels; (3) higher mRNA expression of most intestinal parameters; and (4) increased or decreased corticosterone levels on day 7 and 14 post-infection, respectively. No contribution of liver IgA was observed at the intestinal level. Apparently, the changes following metabolic stress induced by intermittent fasting during food deprivation days increased the resistance to S. typhimurium infection by triggering intestinal IgA production and presumably, pathogen elimination by phagocytic inflammatory cells. © 2014 John Wiley & Sons Ltd.

  9. Proposal and validation of prognostic scoring systems for IgG and IgA monoclonal gammopathies of undetermined significance.

    PubMed

    Rossi, Francesca; Petrucci, Maria Teresa; Guffanti, Andrea; Marcheselli, Luigi; Rossi, Davide; Callea, Vincenzo; Vincenzo, Federico; De Muro, Marianna; Baraldi, Alessandra; Villani, Oreste; Musto, Pellegrino; Bacigalupo, Andrea; Gaidano, Gianluca; Avvisati, Giuseppe; Goldaniga, Maria; Depaoli, Lorenzo; Baldini, Luca

    2009-07-01

    The presenting clinico-hematologic features of 1,283 patients with IgG and IgA monoclonal gammopathies of undetermined significance (MGUS) were correlated with the frequency of evolution into multiple myeloma (MM). Two IgG MGUS populations were evaluated: a training sample (553 patients) and a test sample (378 patients); the IgA MGUS population consisted of 352 patients. Forty-seven of the 553 training group patients and 22 of 378 test group IgG patients developed MM after a median follow-up of 6.7 and 3.6 years, respectively. Multivariate analysis showed that serum monoclonal component (MC) levels of < or =1.5 g/dL, the absence of light-chain proteinuria and normal serum polyclonal immunoglobulin levels defined a prognostically favorable subset of patients, and could be used to stratify the patients into three groups at different 10-year risk of evolution (hazard ratio, 1.0, 5.04, 11.2; P < 0.001). This scoring system was validated in the test sample. Thirty of the 352 IgA patients developed MM after a median follow-up of 4.8 years, and multivariate analysis showed that hemoglobin levels of <12.5 g/dL and reduced serum polyclonal immunoglobulin correlated with progression. A pooled statistical analysis of all of the patients confirmed the validity of Mayo Clinic risk model showing that IgA class, serum MC levels, and light-chain proteinuria are the most important variables correlated with disease progression. Using simple variables, we validated a prognostic model for IgG MGUS. Among the IgA cases, the possible prognostic role of hemoglobin emerged in addition to a decrease in normal immunoglobulin levels.

  10. Latex Clearing Protein—an Oxygenase Cleaving Poly(cis-1,4-Isoprene) Rubber at the cis Double Bonds

    PubMed Central

    Hiessl, Sebastian; Böse, Dietrich; Oetermann, Sylvia; Eggers, Jessica; Pietruszka, Jörg

    2014-01-01

    Gordonia polyisoprenivorans strain VH2, a potent rubber-degrading actinomycete, harbors two latex clearing proteins (Lcps), which are known to be essential for the microbial degradation of rubber. However, biochemical information on the exact role of this protein in the degradation of polyisoprene was lacking. In this study, the gene encoding Lcp1VH2 was heterologously expressed in strains of Escherichia coli, the corresponding protein was purified, and its role in rubber degradation was examined by measurement of oxygen consumption as well as by chromatographic and spectroscopic methods. It turned out that active Lcp1VH2 is a monomer and is responsible for the oxidative cleavage of poly(cis-1,4-isoprene) in synthetic as well as in natural rubber by the addition of oxygen (O2) to the cis double bonds. The resulting oligomers possess repetitive isoprene units with aldehyde (CHO-CH2—) and ketone (—CH2-CO-CH3) functional groups at the termini. Two fractions with average isoprene contents of 18 and 10, respectively, were isolated, thus indicating an endocleavage mechanism. The activity of Lcp1VH2 was determined by applying a polarographic assay. Alkenes, acyclic terpenes, or other rubber-like polymers, such as poly(cis-1,4-butadiene) or poly(trans-1,4-isoprene), are not oxidatively cleaved by Lcp1VH2. The pH and temperature optima of the enzyme are at pH 7 and 30°C, respectively. Furthermore, it was demonstrated that active Lcp1VH2 is a Cu(II)-containing oxygenase that exhibits a conserved domain of unknown function which cannot be detected in any other hitherto-characterized enzyme. The results presented here indicate that this domain might represent a new protein family of oxygenases. PMID:24928880

  11. [Comparison of two rat models of IgA nephropathy].

    PubMed

    Peng, Wei; Liu, Zheng-rong

    2008-10-01

    To study the methods for rapid establishment of rat models of IgA nephropathy. Forty female SD rats weighing 160-200 g were randomized into 3 groups. In group A, the rats received intravenous injection of staphylococcal enterotoxin B (SEB) and oral bovine serum albumin (BSA), and in group B, CCl4 was injected subcutaneously in addition to the above treatments; the rats in group C received no treatments to serve as the normal control group. The rats were sacrificed 10 and 14 weeks after the treatment for biochemical testing of the arterial blood and histopathological and IgA immunofluorescence examination of the renal tissues. The twenty-four-hour urine was collected at 10, 12, and 14 weeks after the treatments for detecting the urine proteins. Compared with the control group, the rats in groups A and B showed significantly increased serum creatinine, urine nitrogen and protein levels. Pathological examination of the renal tissue showed mild to moderate mesangial expansion and mesangial cell proliferation in groups A and B, without obvious difference between the two groups; but hematuria and proteinuria occurred earlier in group B with stronger IgA immunofluorescence than in group A. Both of the methods used in group A and group B can successfully induce IgA nephropathy in rats, but in group B, hematuria and urineprotein occurs earlier and IgA immunofluorescence is more stronger. Therefore intravenous SEB injection combined with oral BSA and subcutaneous CCl4 administration is a better method for time-efficient establishment of rat models of IgA nephropathy.

  12. Reconstitution and structure of a bacterial Pnkp1RnlHen1 RNA repair complex

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Pei; Selvadurai, Kiruthika; Huang, Raven H.

    Ribotoxins cleave essential RNAs for cell killing, and RNA repair neutralizes the damage inflicted by ribotoxins for cell survival. We report a new bacterial RNA repair complex that performs RNA repair linked to immunity. This new RNA repair complex is a 270-kDa heterohexamer composed of three proteins—Pnkp1, Rnl and Hen1—that are required to repair ribotoxin-cleaved RNA in vitro. The crystal structure of the complex reveals the molecular architecture of the heterohexamer as two rhomboid-shaped ring structures of Pnkp1–Rnl–Hen1 heterotrimer fused at the Pnkp1 dimer interface. The four active sites required for RNA repair are located on the inner rim ofmore » each ring. Furthermore, the architecture and the locations of the active sites of the Pnkp1–Rnl–Hen1 heterohexamer suggest an ordered series of repair reactions at the broken RNA ends that confer immunity to recurrent damage.« less

  13. Sera of IgA nephropathy patients contain a heterogeneous population of relatively cationic alpha-heavy chains.

    PubMed

    Shuib, A S; Chua, C T; Hashim, O H

    1998-01-01

    Sera of IgA nephropathy (IgAN) patients and normal subjects were analysed by two-dimensional (2-D) gel electrophoresis. Densitometric analysis of the 2-D gels of IgAN patients and normal subjects revealed that their protein maps were comparable. There was no shift of pI values in the major alpha-heavy chain spots. However, the volume of the alpha-heavy chain bands were differently distributed. Distribution was significantly lower at the anionic region in IgAN patients (mean anionic:cationic ratio of 1.184 +/- 0.311) as compared to normal healthy controls (mean anionic:cationic ratio of 2.139 +/- 0.538). Our data are in support of the previously reported findings that IgA1 of IgAN patients were lacking in sialic acid residues.

  14. IGA: A Simplified Introduction and Implementation Details for Finite Element Users

    NASA Astrophysics Data System (ADS)

    Agrawal, Vishal; Gautam, Sachin S.

    2018-05-01

    Isogeometric analysis (IGA) is a recently introduced technique that employs the Computer Aided Design (CAD) concept of Non-uniform Rational B-splines (NURBS) tool to bridge the substantial bottleneck between the CAD and finite element analysis (FEA) fields. The simplified transition of exact CAD models into the analysis alleviates the issues originating from geometrical discontinuities and thus, significantly reduces the design-to-analysis time in comparison to traditional FEA technique. Since its origination, the research in the field of IGA is accelerating and has been applied to various problems. However, the employment of CAD tools in the area of FEA invokes the need of adapting the existing implementation procedure for the framework of IGA. Also, the usage of IGA requires the in-depth knowledge of both the CAD and FEA fields. This can be overwhelming for a beginner in IGA. Hence, in this paper, a simplified introduction and implementation details for the incorporation of NURBS based IGA technique within the existing FEA code is presented. It is shown that with little modifications, the available standard code structure of FEA can be adapted for IGA. For the clear and concise explanation of these modifications, step-by-step implementation of a benchmark plate with a circular hole under the action of in-plane tension is included.

  15. Processing sites in the human immunodeficiency virus type 1 (HIV-1) Gag-Pro-Pol precursor are cleaved by the viral protease at different rates.

    PubMed

    Pettit, Steve C; Lindquist, Jeffrey N; Kaplan, Andrew H; Swanstrom, Ronald

    2005-11-01

    We have examined the kinetics of processing of the HIV-1 Gag-Pro-Pol precursor in an in vitro assay with mature protease added in trans. The processing sites were cleaved at different rates to produce distinct intermediates. The initial cleavage occurred at the p2/NC site. Intermediate cleavages occurred at similar rates at the MA/CA and RT/IN sites, and to a lesser extent at sites upstream of RT. Late cleavages occurred at the sites flanking the protease (PR) domain, suggesting sequestering of these sites. We observed paired intermediates indicative of half- cleavage of RT/RH site, suggesting that the RT domain in Gag-Pro-Pol was in a dimeric form under these assay conditions. These results clarify our understanding of the processing kinetics of the Gag-Pro-Pol precursor and suggest regulated cleavage. Our results further suggest that early dimerization of the PR and RT domains may serve as a regulatory element to influence the kinetics of processing within the Pol domain.

  16. Evolution of IgA nephropathy into anaphylactoid purpura in six cases--further evidence that IgA nephropathy and Henoch-Schonlein purpura nephritis share common pathogenesis.

    PubMed

    Kamei, Koichi; Ogura, Masao; Sato, Mai; Ito, Shuichi; Ishikura, Kenji

    2016-05-01

    As the morphological and immunohistochemical manifestations of immunoglobulin A (IgA) nephropathy and Henoch-Schonlein purpura nephritis (HSPN) are very similar, they are considered to share a common pathogenesis. Although HSPN usually develops after the appearance of anaphylactoid purpura, we have encountered patients whose renal symptoms preceded purpura. We reviewed the clinical courses of patients who were first diagnosed with IgA nephropathy, but developed purpura later, at the National Center for Child Health and Development in Tokyo, Japan. Of the 53 patients who were diagnosed with primary IgA nephropathy at our institute during the study period (March 2002 to July 2015), six (11 %) developed anaphylactoid purpura after the diagnosis of primary IgA nephropathy and therefore met the inclusion criteria. Duration between the onset of nephritis and subsequent appearance of purpura ranged from 5 months to 14 years. One patient reached end-stage renal failure due to IgA nephropathy and developed purpura after renal transplantation. All renal biopsies performed before the appearance of purpura showed mesangial proliferation with predominant IgA deposits. Urinary findings deteriorated in three patients after the appearance of purpura, including one patient who developed rapidly progressive glomerulonephritis. Renal biopsy findings worsened in two patients. At the last observation, two patients showed mild renal insufficiency. Our clinical experience and previous reports support the argument that IgA nephropathy and HSPN are different manifestations of a single disease. Hence, it is acceptable to consider that they are variants of a single disease.

  17. Translocalized IgA mediates neutralization and stimulates innate immunity inside infected cells.

    PubMed

    Bidgood, Susanna R; Tam, Jerry C H; McEwan, William A; Mallery, Donna L; James, Leo C

    2014-09-16

    IgA is the most prevalent antibody type on mucosal surfaces and the second most prevalent antibody in circulation, yet its role in immune defense is not fully understood. Here we show that IgA is carried inside cells during virus infection, where it activates intracellular virus neutralization and innate immune signaling. Cytosolic IgA-virion complexes colocalize with the high-affinity antibody receptor tripartite motif-containing protein 21 (TRIM21) and are positive for lysine-48 ubiquitin chains. IgA neutralizes adenovirus infection in a TRIM21- and proteasome-dependent manner in both human and mouse cells. Translocated IgA also potently activates NF-κB signaling pathways in cells expressing TRIM21, whereas viral infection in the absence of antibody or TRIM21 is undetected. TRIM21 recognizes an epitope in IgG Fc that is not conserved in IgA; however, fluorescence anisotropy experiments demonstrate that direct binding to IgA is maintained. We use molecular modeling to show that TRIM21 forms a nonspecific hydrophobic seal around a β-loop structure that is present in IgG, IgM, and IgA, explaining how TRIM21 achieves such remarkable broad antibody specificity. The findings demonstrate that the antiviral protection afforded by IgA extends to the intracellular cytosolic environment.

  18. Translocalized IgA mediates neutralization and stimulates innate immunity inside infected cells

    PubMed Central

    Bidgood, Susanna R.; Tam, Jerry C. H.; McEwan, William A.; Mallery, Donna L.; James, Leo C.

    2014-01-01

    IgA is the most prevalent antibody type on mucosal surfaces and the second most prevalent antibody in circulation, yet its role in immune defense is not fully understood. Here we show that IgA is carried inside cells during virus infection, where it activates intracellular virus neutralization and innate immune signaling. Cytosolic IgA–virion complexes colocalize with the high-affinity antibody receptor tripartite motif-containing protein 21 (TRIM21) and are positive for lysine-48 ubiquitin chains. IgA neutralizes adenovirus infection in a TRIM21- and proteasome-dependent manner in both human and mouse cells. Translocated IgA also potently activates NF-κB signaling pathways in cells expressing TRIM21, whereas viral infection in the absence of antibody or TRIM21 is undetected. TRIM21 recognizes an epitope in IgG Fc that is not conserved in IgA; however, fluorescence anisotropy experiments demonstrate that direct binding to IgA is maintained. We use molecular modeling to show that TRIM21 forms a nonspecific hydrophobic seal around a β-loop structure that is present in IgG, IgM, and IgA, explaining how TRIM21 achieves such remarkable broad antibody specificity. The findings demonstrate that the antiviral protection afforded by IgA extends to the intracellular cytosolic environment. PMID:25169018

  19. Intranasal IFNγ extends passive IgA antibody protection of mice against Mycobacterium tuberculosis lung infection

    PubMed Central

    Reljic, R; Clark, S O; Williams, A; Falero-Diaz, G; Singh, M; Challacombe, S; Marsh, P D; Ivanyi, J

    2006-01-01

    Intranasal inoculation of mice with monoclonal IgA against the α-crystallin (acr1) antigen can diminish the tuberculous infection in the lungs. As this effect has been observed only over a short-term, we investigated if it could be extended by inoculation of IFNγ 3 days before infection, and further coinoculations with IgA, at 2 h before and 2 and 7 days after aerosol infection with Mycobacterium tuberculosis H37Rv. This treatment reduced the lung infection at 4 weeks more than either IgA or IFNγ alone (i.e. 17-fold, from 4·2 × 107 to 2·5 × 106 CFU, P = 0·006), accompanied also by lower granulomatous infiltration of the lungs. IFNγ added prior to infection of mouse peritoneal macrophages with IgA-opsonized bacilli resulted in a synergistic increase of nitric oxide and TNFα production and a 2–3 fold decrease in bacterial counts. Our improved results suggest, that combined treatment with IFNγ and IgA could be developed towards prophylactic treatment of AIDS patients, or as an adjunct to chemotherapy. PMID:16487246

  20. Evaluation of three fully automated immunoassay systems for detection of IgA anti-beta 2-glycoprotein I antibodies.

    PubMed

    Pérez, D; Martínez-Flores, J A; Serrano, M; Lora, D; Paz-Artal, E; Morales, J M; Serrano, A

    2016-10-01

    In recent years, we have been witnessing increased clinical interest in the determination of IgA anti-beta 2-glycoprotein I (aB2GPI) antibodies as well as increased demand for this test. Some ELISA-based diagnostic systems for IgA aB2GPI antibodies detection are suboptimal to detect it. The aim of our study was to determine whether the diagnostic yield of modern detection systems based on automatic platforms to measure IgA aB2GPI is equivalent to that of the well-optimized ELISA-based assays. In total, 130 patients were analyzed for IgA aB2GPI by three fully automated immunoassays using an ELISA-based assay as reference. The three systems were also analyzed for IgG aB2GPI with 58 patients. System 1 was able to detect IgA aB2GPI with good sensitivity and kappa index (99% and 0.72, respectively). The other two systems had also poor sensitivity (20% and 15%) and kappa index (0.10 and 0.07), respectively. On the other hand, kappa index for IgG aB2GPI was >0.89 in the three systems. Some analytical methods to detect IgA aB2GPI are suboptimal as well as some ELISA-based diagnostic systems. It is important that the scientific community work to standardize analytical methods to determine IgA aB2GPI antibodies. © 2016 John Wiley & Sons Ltd.

  1. NMR analysis of cleaved Escherichia coli thioredoxin (1-73/74-108) and its P76A variant: cis/trans peptide isomerization.

    PubMed Central

    Yu, W. F.; Tung, C. S.; Wang, H.; Tasayco, M. L.

    2000-01-01

    Inspection of high resolution three-dimensional (3D) structures from the protein database reveals an increasing number of cis-Xaa-Pro and cis-Xaa-Yaa peptide bonds. However, we are still far from being able to predict whether these bonds will remain cis upon single-site substitution of Pro or Yaa and/or cleavage of a peptide bond close to it in the sequence. We have chosen oxidized Escherichia coli thioredoxin (Trx), a member of the Trx superfamily with a single alpha/beta domain and cis P76 to determine the effect of single-site substitution and/or cleavage on this isomer. Standard two-dimensional (2D) NMR analysis were performed on cleaved Trx (1-73/74-108) and its P76A variant. Analysis of the NOE connectivities indicates remarkable similarity between the secondary and supersecondary structure of the noncovalent complexes and Trx. Analysis of the 2D version of the HCCH-TOCSY and HMQC-NOESY-HMQC and 13C-filtered HMQC-NOESY spectra of cleaved Trx with uniformly 13C-labeled 175 and P76 shows surprising conservation of both cis P76 and packing of 175 against W31. A similar NMR analysis of its P76A variant provides no evidence for cis A76 and shows only subtle local changes in both the packing of 175 and the interstrand connectivities between its most protected hydrophobic strands (beta2 and beta4). Indeed, a molecular simulation model for the trans P76A variant of Trx shows only subtle local changes around the substitution site. In conclusion, cleavage of R73 is insufficient to provoke cis/trans isomerization of P76, but cleavage and single-site substitution (P76A) favors the trans isomer. PMID:10739243

  2. Caspase-1 and IL-1β Processing in a Teleost Fish

    PubMed Central

    Reis, Marta I. R.; do Vale, Ana; Pereira, Pedro J. B.; Azevedo, Jorge E.; dos Santos, Nuno M. S.

    2012-01-01

    Interleukine-1β (IL-1β) is the most studied pro-inflammatory cytokine, playing a central role in the generation of systemic and local responses to infection, injury, and immunological challenges. In mammals, IL-1β is synthesized as an inactive 31 kDa precursor that is cleaved by caspase-1 generating a 17.5 kDa secreted active mature form. The caspase-1 cleavage site strictly conserved in all mammalian IL-1β sequences is absent in IL-1β sequences reported for non-mammalian vertebrates. Recently, fish caspase-1 orthologues have been identified in sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) but very little is known regarding their processing and activity. In this work it is shown that sea bass caspase-1 auto-processing is similar to that of the human enzyme, resulting in active p24/p10 and p20/p10 heterodimers. Moreover, the presence of alternatively spliced variants of caspase-1 in sea bass is reported. The existence of caspase-1 isoforms in fish and in mammals suggests that they have been evolutionarily maintained and therefore are likely to play a regulatory role in the inflammatory response, as shown for other caspases. Finally, it is shown that sea bass and avian IL-1β are specifically cleaved by caspase-1 at different but phylogenetically conserved aspartates, distinct from the cleavage site of mammalian IL-1β. PMID:23226286

  3. Toxicological Effects of Nickel Chloride on IgA+ B Cells and sIgA, IgA, IgG, IgM in the Intestinal Mucosal Immunity in Broilers

    PubMed Central

    Wu, Bangyuan; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Huang, Jianying

    2014-01-01

    The objective of this study was to investigate the toxicological effects of dietary NiCl2 on IgA+ B cells and the immunoglobulins including sIgA, IgA, IgG and IgM in the small intestine and cecal tonsil of broilers by the methods of immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). Two hundred and forty one-day-old avian broilers were randomly divided into four groups and fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg NiCl2 for 42 days. Compared with the control group, the IgA+ B cell number and the sIgA, IgA, IgG, and IgM contents in the NiCl2-treated groups were significantly decreased (p < 0.05 or p < 0.01). It was concluded that dietary NiCl2 in the excess of 300 mg/kg had negative effects on the IgA+ B cell number and the abovementioned immunoglobulin contents in the small intestine and the cecal tonsil. NiCl2-reduced sIgA, IgA, IgG and IgM contents is due to decrease in the population and/or the activation of B cell. The results suggest that NiCl2 at high levels has intestinal mucosal humoral immunotoxicity in animals. PMID:25116637

  4. Mucosal IgA increase in rats by continuous CLA feeding during suckling and early infancy.

    PubMed

    Pérez-Cano, Francisco J; Ramírez-Santana, Carolina; Molero-Luís, Marta; Castell, Margarida; Rivero, Montserrat; Castellote, Cristina; Franch, Angels

    2009-03-01

    The aim of this work was to establish the effect of the cis9,trans11 conjugated linoleic acid (CLA) isomer on mucosal immunity during early life in rats, a period when mucosal immunoglobulin production is poorly developed, as is also the case in humans. CLA supplementation was performed during three life periods: gestation, suckling, and early infancy. The immune status of supplemented animals was evaluated at two time points: at the end of the suckling period (21-day-old rats) and 1 week after weaning (28-day-old rats). Secretory IgA was quantified in intestinal washes from 28-day-old rats by ELISA technique. IgA, TGFbeta, and PPARgamma mRNA expression was measured in small intestine and colon by real time PCR, using Taqman specific probes and primers. IgA mucosal production was enhanced in animals supplemented with CLA during suckling and early infancy: in 28-day-old rats, IgA mRNA expression was increased in small intestine and colon by approximately 6- and 4-fold, respectively, and intestinal IgA protein by approximately 2-fold. TGFbeta gene expression was independent of age and type of tissue considered, and was not modified by dietary CLA. Gene expression of PPARgamma, a possible mediator of CLA's effects was also upregulated in animals receiving CLA during early life. In conclusion, dietary supplementation with CLA during suckling and extended to early infancy enhances development of the intestinal immune response in rats.

  5. Production of interleukin-2 (IL-2) and expression of IL-2 receptor in patients with IgA nephropathy.

    PubMed

    Lee, T W; Kim, M J

    1992-01-01

    IL-2 production has been measured in several disease including type I diabetes mellitus, systemic lupus erythematosus, acquired immunodeficiency syndrome and active pulmonary sarcoidosis and its pathogenetic role was suggested. In IgA nephropathy, altered T cell subsets were reported to be associated with increased synthesis of IgA. The altered IL-2 production and the expression of IL-2 receptor might be involved in the pathogenesis of IgA nephropathy. To investigate the role of T cell mediated immunity in the pathogenesis of IgA nephropathy, the immune parameters such as T cell subsets, NK cell activity, interleukin-2 (IL-2) production and IL-2 receptor expression on peripheral blood mononuclear cells (PBMC) were measured before and/or after phytohemagglutinin (PHA) stimulation in 15 patients with IgA nephropathy. Age and sex matched 15 healthy controls and the correlations between the IL-2 production and immune parameters were evaluated. The mean percentages of T helper/inducer cells (CD4), T suppressor/cytotoxic cells (CD8) and the CD4/CD8 ratio of the patients were not different from those of controls and the proportions of CD8 CD11b cell in the patients (21.0 +/- 3.6%) were significantly lower than those in controls (30.5 +/- 5.3%) (p < 0.005). The production of IL-2 by fresh PBMC of both patients and controls was in undetectable ranges. The production of IL-2 by PHA stimulated PBMC of patients was significantly higher than that of controls (140.03 +/- 43.2 U/ml vs 106.5 +/- 42.1 U/ml, p < 0.05). The proportions of lymphocytes expressing the IL-2 receptor (CD25) before the stimulation with PHA in patients were 1.22 +/- 1.00 percent and were not different from those in controls (1.12 +/- 0.78 percent). The correlations between the production of IL-2 and the concentrations of serum IgA, the degrees of histologic alterations and the proportions of CD8 and CD8CD11b cells were not significant. There was a weak tendency of a positive correlation (p < 0.1) between

  6. The sites of catabolism of murine monomeric IgA.

    PubMed

    Moldoveanu, Z; Epps, J M; Thorpe, S R; Mestecky, J

    1988-07-01

    The tissue sites of monomeric IgA (mIgA) catabolism were determined in a BALB/c mouse model. Mouse mIgA myeloma proteins were labeled either by direct iodination or by coupling the residualizing label, dilactitol-125I-tyramine (125I-DLT) to the proteins; catabolites from protein labeled with 125I-DLT accumulate at the site of protein degradation, allowing identification of the tissue and cellular sites involved in catabolism of the protein. The circulating half-lives of 125I- and 125I-DLT-mIgA were the same. The distribution of radioactivity in tissues was measured at 1, 3, 24, and 96 h after iv. injection of 125I-DLT-labeled mIgA, dimeric IgA (dIgA), IgG, or mouse serum albumin. The greatest uptake of 125I-DLT-mIgA was attributable to the liver. This organ accounted for more internal catabolism of mIgA than all other tissues combined. In contrast, 125I-DLT-IgG was catabolized equally in skin, muscle, and liver. These data indicate that, in mice, the liver is the major site of mIgA catabolism. To determine the cell types involved, collagenase digestion was used to isolate parenchymal and non-parenchymal cells from perfused liver of animals injected with 125-DLT-mIgA. Most of the radioactivity was associated with the hepatocyte fraction, even though both cell types showed uptake of 125I-DLT-mIgA. Inhibition studies, with asialofetuin and mouse IgA demonstrated that the uptake of mIgA by liver cells was mediated primarily by the asialoglycoprotein receptor.

  7. Recognition of Epidermal Transglutaminase by IgA and Tissue Transglutaminase 2 Antibodies in a Rare Case of Rhesus Dermatitis

    PubMed Central

    Sestak, Karol; Mazumdar, Kaushiki; Midkiff, Cecily C.; Dufour, Jason; Borda, Juan T.; Alvarez, Xavier

    2011-01-01

    Tissue transglutaminase 2 (tTG2) is an intestinal digestive enzyme which deamidates already partially digested dietary gluten e.g. gliadin peptides. In genetically predisposed individuals, tTG2 triggers autoimmune responses that are characterized by the production of tTG2 antibodies and their direct deposition into small intestinal wall 1,2. The presence of such antibodies constitutes one of the major hallmarks of the celiac disease (CD). Epidermal transglutaminase (eTG) is another member of the transglutaminase family that can also function as an autoantigen in a small minority of CD patients. In these relatively rare cases, eTG triggers an autoimmune reaction (a skin rash) clinically known as dermatitis herpetiformis (DH). Although the exact mechanism of CD and DH pathogenesis is not well understood, it is known that tTG2 and eTG share antigenic epitopes that can be recognized by serum antibodies from both CD and DH patients 3,4. In this study, the confocal microscopy examination of biopsy samples from skin lesions of two rhesus macaques (Macaca mulatta) with dermatitis (Table 1, Fig. 1 and 2) was used to study the affected tissues. In one animal (EM96) a spectral overlap of IgA and tTG2 antibodies (Fig. 3) was demonstrated. The presence of double-positive tTG2+IgA+ cells was focused in the deep epidermis, around the dermal papillae. This is consistent with lesions described in DH patients 3. When EM96 was placed on a gluten-free diet, the dermatitis, as well as tTG2+IgA+ deposits disappeared and were no longer detectable (Figs. 1-3). Dermatitis reappeared however, based on re-introduction of dietary gluten in EM96 (not shown). In other macaques including animal with unrelated dermatitis, the tTG2+IgA+ deposits were not detected. Gluten-free diet-dependent remission of dermatitis in EM96 together with presence of tTG2+IgA+ cells in its skin suggest an autoimmune, DH-like mechanism for the development of this condition. This is the first report of DH

  8. A novel method for detecting IgA endomysial antibodies by using human umbilical vein endothelial cells.

    PubMed

    Castellino, F; Scaglione, N; Grosso, S B; Sategna-Guidetti, C

    2000-01-01

    Although tissue transglutaminase was recently identified as the main autoantigen recognized by endomysial antibodies in coeliac patients, anti-endomysium antibody detection still persists as the gold standard for coeliac disease screening and diagnosis. (1) To evaluate human umbilical vein cells (HUVEC) as an alternative source of endomysial antigen and to assess their suitability in the diagnosis of coeliac disease. (2) To verify whether tissue transglutaminase is one target antigen eliciting the endomysial antibody fraction of coeliac serum IgA. University teaching hospital. Sera from 123 untreated adults with biopsy-proven coeliac disease and 84 controls (40 healthy and 44 diseased) were assessed by indirect immunofluorescence, using HUVEC on glass slides prepared by cytocentrifugation and permeabilized by using Triton X (0.5%). Indirect immunofluorescence was performed: (1) using coeliac disease serum samples on HUVEC with or without prior incubation with tissue transglutaminase; and (2) incubating both HUVEC and monkey oesophagus with goat anti-guinea pig tissue transglutaminase antibody. All the coeliac patients, who were also positive on monkey oesophagus, showed the typical fluorescent homogeneous cytoplasmic stain on HUVEC. All control sera were negative both on HUVEC and on monkey oesophagus. IgA antibodies did not react with non-permeabilized cells, with intact membrane. Preincubation of coeliac sera with tissue transglutaminase abolished the typical fluorescent pattern. The incubation of anti-tissue transglutaminase antibody with monkey oesophagus and HUVEC resulted in an immunofluorescence staining pattern identical to that obtained with positive coeliac sera. (1) As a substrate for anti-endomysial antibody, HUVEC may provide the same diagnostic accuracy as monkey oesophagus, thus bypassing economical and ethical problems. The HUVEC antigen reacting with IgA from coeliac disease sera is an intracellular rather than a cell-surface antigen, as IgA

  9. Dual renin-angiotensin system blockade plus oral methylprednisone for the treatment of proteinuria in IgA nephropathy.

    PubMed

    Trimarchi, Hernán; Muryan, Alexis; Young, Pablo; Forrester, Mariano; Iotti, Alejandro; Pereyra, Horacio; Lombi, Fernando; Seminario, Omar; Alonso, Mirta; Iotti, Roberto

    2007-01-01

    Renin-angiotensin system inhibition is a widely accepted approach to initially deal with proteinuria in IgA nephropathy, while the role of immunosuppressants remains controversial in many instances. A prospective, uncontrolled, open-label trial was undertaken in patients with biopsy-proven IgA nephropathy with proteinuria > 0.5 g/day and normal renal function to assess the efficacy of a combination treatment of angiotensin converting enzyme inhibitors plus angiotensin receptor blockers enalapril valsartan coupled with methylprednisone to decrease proteinuria to levels below 0.5 g/day. Twenty patients were included: Age 37.45 +/- 13.26 years (50% male); 7 patients (35%) were hypertensive; proteinuria 2.2 +/- 1.86 g/day; serum creatinine 1.07 +/- 0.29 mg/dl; mean follow-up 60.10 +/- 31.47 months. IgA nephropathy was subclassified according to Haas criteria. Twelve patients (60%) were class II; seven (35%) were class III and one (5%) class V. All patients received dual renin-angiotensin system blockade as tolerated. Oral methylprednisone was started at 0.5 mg/kg/day for the initial 8 weeks and subsequently tapered bi-weekly until the maintenance dose of 4 mg was reached. Oral steroids were discontinued after 24 weeks (6 months) of therapy but renin-angiotensin inhibition remained unchanged. At 10 weeks of therapy proteinuria decreased to 0.15 +/- 0.07 g/day (P < 0.001) while serum creatinine did not vary: 1.07 +/- 0.28 mg/dl (P = ns). After a mean follow-up of 42.36 +/- 21.56 months urinary protein excretion (0.12 +/- 0.06 g/day) and renal function (serum creatinine 1.06 +/- 0.27 mg/dl) remained stable. No major side effects were reported during the study. Renin-angiotensin blockade plus oral steroids proved useful to significantly decrease proteinuria to < 0.5 g/day in patients with IgA nephropathy without changes in renal function.

  10. Value of Isolated IgA anti-β2GPI Positivity in the Diagnosis of the Antiphospholipid Syndrome

    PubMed Central

    Murthy, Vijaya; Willis, Rohan; Romay-Penabad, Zurina; Ruiz-Limón, Patricia; Martínez-Martínez, Laura A.; Jatwani, Shraddha; Jajoria, Praveen; Seif, Alan; Alarcón, Graciela S.; Papalardo, Elizabeth; Liu, Jigna; Vilá, Luis M.; McGwin, Gerald; McNearney, Terry A.; Maganti, Rashmi; Sunkureddi, Prashanth; Parekh, Trisha; Tarantino, Michael; Akhter, Ehtisham; Fang, Hong; Gonzalez, Emilio B.; Binder, Walter R.; Norman, Gary L.; Shums, Zakera; Teodorescu, Marius; Reveille, John D.; Petri, Michelle; Pierangeli, Silvia S.

    2014-01-01

    Purpose To examine the prevalence of isolated IgA anti-β2Glycoprotein I (anti-β2GPI) positivity and the association of these antibodies, and a subgroup that bind specifically to domain IV/V of β2GPI, with clinical manifestations of the Antiphospholipid Syndrome (APS) in three patients groups. The pathogenicity of IgA anti-β2GPI was also evaluated in a mouse model of thrombosis. Methods Patients with systemic lupus erythematosus (SLE) from a multiethnic, multicenter cohort (LUpus in MInorities, NAture versus nurture [LUMINA]) (n=558), patients with SLE from the Hopkins Lupus Cohort (n=215), and serum samples referred to the Antiphospholipid Standardization Laboratory (APLS) (n=5,098) were evaluated. IgA anti-β2GPI titers and binding to domain IV/V of β2GPI were examined by enzyme-linked immunosorbent assay (ELISA). CD1 mice were inoculated with purified IgA anti- β2GPI antibodies, and surgical procedures and ELISAs were performed to evaluate thrombus development and tissue factor (TF) activity. Results A total of 198 patients were found to be positive for IgA anti-β2GPI isotype, and 57 patients were positive exclusively for IgA anti-β2GPI antibodies. Of these, 13 of 23 patients (56.5%) in the LUMINA cohort, 17 of 17 patients (100%) in the Hopkins cohort, and 10 of 17 patients (58.9%) referred to APLS had at least one APS-related clinical manifestation. Fifty-four percent of all the IgA anti-β2GPI positive serum samples reacted with domain IV/V of anti-β2GPI, and 77% of those had clinical features of APS. Isolated IgA anti-β2GPI positivity was associated with an increased risk for arterial thrombosis (p<0.001), venous thrombosis (p=0.015) and all thrombosis (p<0.001). The association between isolated IgA anti-β2GPI and arterial thrombosis (p=0.0003) and all thrombosis (p=0.0003) remained significant after adjusting for other risk factors for thrombosis. In vivo mouse studies demonstrated that IgA anti-β2GPI antibodies induced significantly larger

  11. Dysfunctions of the Iga system: a common link between intestinal and renal diseases

    PubMed Central

    Papista, Christina; Berthelot, Laureline; Monteiro, Renato C

    2011-01-01

    Immunoglobulin A (Iga)-isotype antibodies play an important role in immunity owing to their structure, glycosylation, localization and receptor interactions. Dysfunctions in this system can lead to multiple types of pathology. This review describes the characteristics of Iga and discusses the involvement of abnormalities in the Iga system on the development of celiac disease and Iga nephropathy. PMID:21278767

  12. Effect of Oral Methylprednisolone on Clinical Outcomes in Patients With IgA Nephropathy: The TESTING Randomized Clinical Trial.

    PubMed

    Lv, Jicheng; Zhang, Hong; Wong, Muh Geot; Jardine, Meg J; Hladunewich, Michelle; Jha, Vivek; Monaghan, Helen; Zhao, Minghui; Barbour, Sean; Reich, Heather; Cattran, Daniel; Glassock, Richard; Levin, Adeera; Wheeler, David; Woodward, Mark; Billot, Laurent; Chan, Tak Mao; Liu, Zhi-Hong; Johnson, David W; Cass, Alan; Feehally, John; Floege, Jürgen; Remuzzi, Giuseppe; Wu, Yangfeng; Agarwal, Rajiv; Wang, Hai-Yan; Perkovic, Vlado

    2017-08-01

    Guidelines recommend corticosteroids in patients with IgA nephropathy and persistent proteinuria, but the effects remain uncertain. To evaluate the efficacy and safety of corticosteroids in patients with IgA nephropathy at risk of progression. The Therapeutic Evaluation of Steroids in IgA Nephropathy Global (TESTING) study was a multicenter, double-blind, randomized clinical trial designed to recruit 750 participants with IgA nephropathy (proteinuria greater than 1 g/d and estimated glomerular filtration rate [eGFR] of 20 to 120 mL/min/1.73 m2 after at least 3 months of blood pressure control with renin-angiotensin system blockade] and to provide follow-up until 335 primary outcomes occurred. Patients were randomized 1:1 to oral methylprednisolone (0.6-0.8 mg/kg/d; maximum, 48 mg/d) (n = 136) or matching placebo (n = 126) for 2 months, with subsequent weaning over 4 to 6 months. The primary composite outcome was end-stage kidney disease, death due to kidney failure, or a 40% decrease in eGFR. Predefined safety outcomes were serious infection, new diabetes, gastrointestinal hemorrhage, fracture/osteonecrosis, and cardiovascular events. The mean required follow-up was estimated to be 5 years. After randomization of 262 participants (mean age, 38.6 [SD, 11.1] years; 96 [37%] women; eGFR, 59.4 mL/min/1.73 m2; urine protein excretion, 2.40 g/d) and 2.1 years' median follow-up, recruitment was discontinued because of excess serious adverse events. Serious events occurred in 20 participants (14.7%) in the methylprednisolone group vs 4 (3.2%) in the placebo group (P = .001; risk difference, 11.5% [95% CI, 4.8%-18.2%]), mostly due to excess serious infections (11 [8.1%] vs 0; risk difference, 8.1% [95% CI, 3.5%-13.9%]; P < .001), including 2 deaths. The primary renal outcome occurred in 8 participants (5.9%) in the methylprednisolone group vs 20 (15.9%) in the placebo group (hazard ratio, 0.37 [95% CI, 0.17-0.85]; risk difference, 10.0% [95% CI, 2

  13. Cleaved Form of Osteopontin in Urine as a Clinical Marker of Lupus Nephritis

    PubMed Central

    Kitagori, Koji; Yoshifuji, Hajime; Oku, Takuma; Sasaki, Chiyomi; Miyata, Hitomi; Mori, Keita P.; Nakajima, Toshiki; Ohmura, Koichiro; Kawabata, Daisuke; Yukawa, Naoichiro; Imura, Yoshitaka; Murakami, Kosaku; Nakashima, Ran; Usui, Takashi; Fujii, Takao; Sakai, Kaoru; Yanagita, Motoko; Hirayama, Yoshitaka; Mimori, Tsuneyo

    2016-01-01

    We assessed the utility of two forms of osteopontin (OPN), OPN full and its cleaved form (OPN N-half), in plasma and urine as markers of disease activity in lupus nephritis (LN). Samples were collected from patients with systemic lupus erythematosus (SLE) (LN: N = 29, non-LN: N = 27), IgA nephropathy (IgAN) (N = 14), minimal change nephrotic syndrome (MCNS) (N = 5), diabetic nephropathy (DN) (N = 14) and healthy volunteers (HC) (N = 17). While there was no significant difference in urine OPN full concentration between groups, urine OPN N-half concentration was significantly higher in patients with LN than HC (p < 0.05). Moreover, urine OPN N-half was higher in LN patients with overt proteinuria (urine protein/creatinine ratio: P/C > 0.5) than LN patients with minimal proteinuria (P/C < 0.5, p < 0.0001), and also higher than in DN patients with overt proteinuria (P/C > 0.5, p < 0.01). Urine thrombin activity correlated with urine OPN N-half concentration (p < 0.0001), but not with urine OPN full concentration. These results suggest that urine OPN N-half concentration reflects renal inflammation. Thus, urine OPN N-half may be a novel disease activity marker for LN. PMID:27992535

  14. Simultaneous Subcutaneous and Intranasal Administration of a CAF01-Adjuvanted Chlamydia Vaccine Elicits Elevated IgA and Protective Th1/Th17 Responses in the Genital Tract

    PubMed Central

    Wern, Jeanette Erbo; Sorensen, Maria Rathmann; Olsen, Anja Weinreich; Andersen, Peter; Follmann, Frank

    2017-01-01

    The selection of any specific immunization route is critical when defining future vaccine strategies against a genital infection like Chlamydia trachomatis (C.t.). An optimal Chlamydia vaccine needs to elicit mucosal immunity comprising both neutralizing IgA/IgG antibodies and strong Th1/Th17 responses. A strategic tool to modulate this immune profile and mucosal localization of vaccine responses is to combine parenteral and mucosal immunizations routes. In this study, we investigate whether this strategy can be adapted into a two-visit strategy by simultaneous subcutaneous (SC) and nasal immunization. Using a subunit vaccine composed of C.t. antigens (Ags) adjuvanted with CAF01, a Th1/Th17 promoting adjuvant, we comparatively evaluated Ag-specific B and T cell responses and efficacy in mice following SC and simultaneous SC and nasal immunization (SIM). We found similar peripheral responses with regard to interferon gamma and IL-17 producing Ag-specific splenocytes and IgG serum levels in both vaccine strategies but in addition, the SIM protocol also led to Ag-specific IgA responses and increased B and CD4+ T cells in the lung parenchyma, and in lower numbers also in the genital tract (GT). Following vaginal infection with C.t., we observed that SIM immunization gave rise to an early IgA response and IgA-secreting plasma cells in the GT in contrast to SC immunization, but we were not able to detect more rapid recruitment of mucosal T cells. Interestingly, although SIM vaccination in general improved mucosal immunity we observed no improved efficacy against genital infection compared to SC, a finding that warrants for further investigation. In conclusion, we demonstrate a novel vaccination strategy that combines systemic and mucosal immunity in a two-visit strategy. PMID:28567043

  15. Levels and complexity of IgA antibody against oral bacteria in samples of human colostrum.

    PubMed

    Petrechen, L N; Zago, F H; Sesso, M L T; Bertoldo, B B; Silva, C B; Azevedo, K P; de Lima Pereira, S A; Geraldo-Martins, V R; Ferriani, V P L; Nogueira, R D

    2015-01-01

    Streptococcus mutans (SM) have three main virulence antigens: glucan binding protein B (gbpB), glucosyltransferase (Gtf) and antigens I/II (Ag I/II) envolved in the capacity of those bacteria to adhere and accumulate in the dental biofilm. Also, the glycosyltransferases 153 kDa of Streptococcus gordonii (SGO) and 170kDa of Streptococcus sanguinis (SSA) were important antigens associated with the accumulation of those bacterias. Streptococcus mitis (SMI) present IgA1 protease of 202 kDa. We investigated the specificity and levels IgA against those antigens of virulence in samples of human colostrum. This study involved 77 samples of colostrum that were analyzed for levels of immunoglobulian A, M and G by Elisa. The specificity of IgA against extracts of SM and initials colonizators (SSA, SMI, SGO) were analyzed by the Western blot. The mean concentration of IgA was 2850.2 (±2567.2) mg/100 mL followed by IgM and IgG (respectively 321.8±90.3 and 88.3±51.5), statistically different (p<0.05). Results showed that the majority of samples had detectable levels of IgA antibodies to extracts of bacteria antigens and theirs virulence antigens. To SM, the GbpB was significantly lower detected than others antigens of SM (p<0.05). High complexities of response to Ags were identified in the samples. There were no significant differences in the mean number of IgA-reactive Ags between the antigens (p>0.4). So, the breast milk from first hours after birth presented significant levels of IgA specific against important virulence of antigens those oral streptococci, which can disrupt the installation and accumulation process of these microorganisms in the oral cavity. Copyright © 2014 Elsevier GmbH. All rights reserved.

  16. Defective anti-polysaccharide IgG vaccine responses in IgA deficient mice.

    PubMed

    Furuya, Yoichi; Kirimanjeswara, Girish S; Roberts, Sean; Racine, Rachael; Wilson-Welder, Jennifer; Sanfilippo, Alan M; Salmon, Sharon L; Metzger, Dennis W

    2017-09-05

    We report that IgA -/- mice exhibit specific defects in IgG antibody responses to various polysaccharide vaccines (Francisella tularensis LPS and Pneumovax), but not protein vaccines such as Fluzone. This defect further included responses to polysaccharide-protein conjugate vaccines (Prevnar and Haemophilus influenzae type b-tetanus toxoid vaccine). In agreement with these findings, IgA -/- mice were protected from pathogen challenge with protein- but not polysaccharide-based vaccines. Interestingly, after immunization with live bacteria, IgA +/+ and IgA -/- mice were both resistant to lethal challenge and their IgG anti-polysaccharide antibody responses were comparable. Immunization with live bacteria, but not purified polysaccharide, induced production of serum B cell-activating factor (BAFF), a cytokine important for IgG class switching; supplementing IgA -/- cell cultures with BAFF enhanced in vitro polyclonal IgG production. Taken together, these findings show that IgA deficiency impairs IgG class switching following vaccination with polysaccharide antigens and that live bacterial immunization can overcome this defect. Since IgA deficient patients also often show defects in antibody responses following immunization with polysaccharide vaccines, our findings could have relevance to the clinical management of this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Cleaved-coupled nanowire lasers

    PubMed Central

    Gao, Hanwei; Fu, Anthony; Andrews, Sean C.; Yang, Peidong

    2013-01-01

    The miniaturization of optoelectronic devices is essential for the continued success of photonic technologies. Nanowires have been identified as potential building blocks that mimic conventional photonic components such as interconnects, waveguides, and optical cavities at the nanoscale. Semiconductor nanowires with high optical gain offer promising solutions for lasers with small footprints and low power consumption. Although much effort has been directed toward controlling their size, shape, and composition, most nanowire lasers currently suffer from emitting at multiple frequencies simultaneously, arising from the longitudinal modes native to simple Fabry–Pérot cavities. Cleaved-coupled cavities, two Fabry–Pérot cavities that are axially coupled through an air gap, are a promising architecture to produce single-frequency emission. The miniaturization of this concept, however, imposes a restriction on the dimensions of the intercavity gaps because severe optical losses are incurred when the cross-sectional dimensions of cavities become comparable to the lasing wavelength. Here we theoretically investigate and experimentally demonstrate spectral manipulation of lasing modes by creating cleaved-coupled cavities in gallium nitride (GaN) nanowires. Lasing operation at a single UV wavelength at room temperature was achieved using nanoscale gaps to create the smallest cleaved-coupled cavities to date. Besides the reduced number of lasing modes, the cleaved-coupled nanowires also operate with a lower threshold gain than that of the individual component nanowires. Good agreement was found between the measured lasing spectra and the predicted spectral modes obtained by simulating optical coupling properties. This agreement between theory and experiment presents design principles to rationally control the lasing modes in cleaved-coupled nanowire lasers. PMID:23284173

  18. The Nodulation Factor Hydrolase of Medicago truncatula: Characterization of an Enzyme Specifically Cleaving Rhizobial Nodulation Signals1[W][OPEN

    PubMed Central

    Tian, Ye; Liu, Wei; Cai, Jie; Zhang, Lan-Yue; Wong, Kam-Bo; Feddermann, Nadja; Boller, Thomas; Xie, Zhi-Ping; Staehelin, Christian

    2013-01-01

    Nodule formation induced by nitrogen-fixing rhizobia depends on bacterial nodulation factors (NFs), modified chitin oligosaccharides with a fatty acid moiety. Certain NFs can be cleaved and inactivated by plant chitinases. However, the most abundant NF of Sinorhizobium meliloti, an O-acetylated and sulfated tetramer, is resistant to hydrolysis by all plant chitinases tested so far. Nevertheless, this NF is rapidly degraded in the host rhizosphere. Here, we identify and characterize MtNFH1 (for Medicago truncatula Nod factor hydrolase 1), a legume enzyme structurally related to defense-related class V chitinases (glycoside hydrolase family 18). MtNFH1 lacks chitinase activity but efficiently hydrolyzes all tested NFs of S. meliloti. The enzyme shows a high cleavage preference, releasing exclusively lipodisaccharides from NFs. Substrate specificity and kinetic properties of MtNFH1 were compared with those of class V chitinases from Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum), which cannot hydrolyze tetrameric NFs of S. meliloti. The Michaelis-Menten constants of MtNFH1 for NFs are in the micromolar concentration range, whereas nonmodified chitin oligosaccharides represent neither substrates nor inhibitors for MtNFH1. The three-dimensional structure of MtNFH1 was modeled on the basis of the known structure of class V chitinases. Docking simulation of NFs to MtNFH1 predicted a distinct binding cleft for the fatty acid moiety, which is absent in the class V chitinases. Point mutation analysis confirmed the modeled NF-MtNFH1 interaction. Silencing of MtNFH1 by RNA interference resulted in reduced NF degradation in the rhizosphere of M. truncatula. In conclusion, we have found a novel legume hydrolase that specifically inactivates NFs. PMID:24082029

  19. IgA measurements in over 12 000 Swedish twins reveal sex differential heritability and regulatory locus near CD30L

    PubMed Central

    Viktorin, Alexander; Frankowiack, Marcel; Padyukov, Leonid; Chang, Zheng; Melén, Erik; Sääf, Annika; Kull, Inger; Klareskog, Lars; Hammarström, Lennart; Magnusson, Patrik K.E.

    2014-01-01

    In a broad attempt to improve the understanding of the genetic regulation of serum IgA levels, the heritability was estimated in over 12 000 Swedish twins, and a genome-wide association study was conducted in a subsample of 9617. Using the classical twin model the heritability was found to be significantly larger among females (61%) compared with males (21%), while contribution from shared environment (20%) was only seen for males. By modeling the genetic relationship matrix with IgA levels, we estimate that a substantial proportion (31%) of variance in IgA levels can ultimately be explained by the investigated SNPs. The genome-wide association study revealed significant association to two loci: (i) rs6928791 located on chromosome 6, 22 kb upstream of the gene SAM and SH3 domain containing 1 (SASH1) and (ii) rs13300483 on chromosome 9, situated 12 kb downstream the CD30 ligand (CD30L) encoding gene. The association to rs13300483 was replicated in two additional independent Swedish materials. The heritability of IgA levels is moderate and can partly be attributable to common variation in the CD30L locus. PMID:24676358

  20. Interaction of human, rat, and mouse immunoglobulin A (IgA) with Staphylococcal superantigen-like 7 (SSL7) decoy protein and leukocyte IgA receptor.

    PubMed

    Wines, Bruce D; Ramsland, Paul A; Trist, Halina M; Gardam, Sandra; Brink, Robert; Fraser, John D; Hogarth, P Mark

    2011-09-23

    Host survival depends on an effective immune system and pathogen survival on the effectiveness of immune evasion mechanisms. Staphylococcus aureus utilizes a number of molecules to modulate host immunity, including the SSL family of which SSL7 binds IgA and inhibits Fcα receptor I (FcαRI)-mediated function. Other Gram-positive bacterial pathogens produce IgA binding proteins, which, similar to SSL7, also bind the Fc at the CH2/CH3 interface (the junction between constant domains 2 and 3 of the heavy chain). The opposing activities of the host FcαRI-IgA receptor ligand pair and the pathogen decoy proteins select for host and pathogen variants, which exert stronger protection or evasion, respectively. Curiously, mouse but not rat IgA contains a putative N-linked glycosylation site in the center of this host receptor and pathogen-binding site. Here, we demonstrate that this site is glycosylated and that the effect of amino acid changes and glycosylation of the CH2/CH3 interface inhibits interaction with the pathogen IgA binding protein SSL7, while maintaining binding of pIgR, essential to the biosynthesis and transport of SIgA.

  1. Isolated lymphoid follicles are not IgA inductive sites for recombinant Salmonella

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashizume, Tomomi; Momoi, Fumiki; Kurita-Ochiai, Tomoko

    2007-08-24

    In this study, we investigated whether isolated lymphoid follicles (ILF) play a role in the regulation of intestinal IgA antibody (Ab) responses. The transfer of wild type (WT) bone marrow (BM) to lymphotoxin-{alpha}-deficient (LT{alpha}{sup -/-}) mice resulted in the formation of mature ILF containing T cells, B cells, and FDC clusters in the absence of mesenteric lymph nodes and Peyer's patches. Although the ILF restored total IgA Abs in the intestine, antigen (Ag)-specific IgA responses were not induced after oral immunization with recombinant Salmonella expressing fragment C of tetanus toxin. Moreover, Ag-specific cell proliferation was not detected in the ILF.more » Interestingly, no IgA anti-LPS Abs were detected in the fecal extracts of LT{alpha}{sup -/-} mice reconstituted with WT BM. On the basis of these findings, ILF can be presumed to play a role in the production of IgA Abs, but lymphoid nodules are not inductive sites for the regulation of Ag-specific intestinal IgA responses to recombinant Salmonella.« less

  2. Human Plasma-derived Polymeric IgA and IgM Antibodies Associate with Secretory Component to Yield Biologically Active Secretory-like Antibodies*

    PubMed Central

    Longet, Stéphanie; Miled, Sarah; Lötscher, Marius; Miescher, Sylvia M.; Zuercher, Adrian W.; Corthésy, Blaise

    2013-01-01

    Immunotherapy with monoclonal and polyclonal immunoglobulin is successfully applied to improve many clinical conditions, including infection, autoimmune diseases, or immunodeficiency. Most immunoglobulin products, recombinant or plasma-derived, are based on IgG antibodies, whereas to date, the use of IgA for therapeutic application has remained anecdotal. In particular, purification or production of large quantities of secretory IgA (SIgA) for potential mucosal application has not been achieved. In this work, we sought to investigate whether polymeric IgA (pIgA) recovered from human plasma is able to associate with secretory component (SC) to generate SIgA-like molecules. We found that ∼15% of plasma pIgA carried J chain and displayed selective SC binding capacity either in a mixture with monomeric IgA (mIgA) or after purification. The recombinant SC associated covalently in a 1:1 stoichiometry with pIgA and with similar efficacy as colostrum-derived SC. In comparison with pIgA, the association with SC delayed degradation of SIgA by intestinal proteases. Similar results were obtained with plasma-derived IgM. In vitro, plasma-derived IgA and SIgA neutralized Shigella flexneri used as a model pathogen, resulting in a delay of bacteria-induced damage targeted to polarized Caco-2 cell monolayers. The sum of these novel data demonstrates that association of plasma-derived IgA or IgM with recombinant/colostrum-derived SC is feasible and yields SIgA- and SIgM-like molecules with similar biochemical and functional characteristics as mucosa-derived immunoglobulins. PMID:23250751

  3. Processing sites in the human immunodeficiency virus type 1 (HIV-1) Gag-Pro-Pol precursor are cleaved by the viral protease at different rates

    PubMed Central

    Pettit, Steve C; Lindquist, Jeffrey N; Kaplan, Andrew H; Swanstrom, Ronald

    2005-01-01

    We have examined the kinetics of processing of the HIV-1 Gag-Pro-Pol precursor in an in vitro assay with mature protease added in trans. The processing sites were cleaved at different rates to produce distinct intermediates. The initial cleavage occurred at the p2/NC site. Intermediate cleavages occurred at similar rates at the MA/CA and RT/IN sites, and to a lesser extent at sites upstream of RT. Late cleavages occurred at the sites flanking the protease (PR) domain, suggesting sequestering of these sites. We observed paired intermediates indicative of half- cleavage of RT/RH site, suggesting that the RT domain in Gag-Pro-Pol was in a dimeric form under these assay conditions. These results clarify our understanding of the processing kinetics of the Gag-Pro-Pol precursor and suggest regulated cleavage. Our results further suggest that early dimerization of the PR and RT domains may serve as a regulatory element to influence the kinetics of processing within the Pol domain. PMID:16262906

  4. Rapamycin slows IgA nephropathy progression in the rat.

    PubMed

    Tian, Jihua; Wang, Yanhong; Zhou, Xiaoshuang; Li, Yanjiao; Wang, Chen; Li, Jiaming; Li, Rongshan

    2014-01-01

    IgA nephropathy (IgAN) is the most frequent glomerulonephritis worldwide. Different therapeutic approaches have been tested against IgAN. The present study was designed to explore the renoprotective potential of low-dose mammalian target of rapamycin (mTOR) inhibitor rapamycin in an IgAN rat model and the possible mechanism of action. After establishing an IgAN model, the rats were randomly divided into four groups: control, control with rapamycin treatment, IgAN model, and IgAN model with rapamycin treatment. Coomassie Brilliant Blue was utilized to measure 24-hour urinary protein levels. Hepatic and renal function was determined with an autoanalyzer. Proliferation was assayed via 5-bromo-2'-deoxyuridine incorporation. Real-time PCR and immunohistochemistry were utilized to detect the expression of α-SMA, collagen I, collagen III, TGF-β1 and platelet-derived growth factor. Western blotting and immunohistochemistry were performed to determine p-S6 protein levels. Low-dose mTOR inhibitor rapamycin prevented an additional increase in proteinuria and protected kidney function in a model of IgAN. Rapamycin directly or indirectly interfered with multiple key pathways in the progression of IgAN to end-stage renal disease: (1) reduced the deposition of IgA and inhibited cell proliferation; (2) decreased the expression of fibrosis markers α-SMA and type III collagen, and (3) downregulated the expression of the profibrotic growth factors platelet-derived growth factor and TGF-β1. The expression of p-S6 was significantly elevated in IgAN rats. The mTOR pathway was activated in IgAN rats and the early application of low-dose mTOR inhibitor rapamycin may slow the renal injury of IgAN in rats.

  5. Evaluation of intra- and extra-epithelial secretory IgA in chlamydial infections

    PubMed Central

    Armitage, Charles W; O’Meara, Connor P; Harvie, Marina C G; Timms, Peter; Wijburg, Odilia L; Beagley, Kenneth W

    2014-01-01

    Immunoglobulin A is an important mucosal antibody that can neutralize mucosal pathogens by either preventing attachment to epithelia (immune exclusion) or alternatively inhibit intra-epithelial replication following transcytosis by the polymeric immunoglobulin receptor (pIgR). Chlamydia trachomatis is a major human pathogen that initially targets the endocervical or urethral epithelium in women and men, respectively. As both tissues contain abundant secretory IgA (SIgA) we assessed the protection afforded by IgA targeting different chlamydial antigens expressed during the extra- and intra-epithelial stages of infection. We developed an in vitro model using polarizing cells expressing the murine pIgR together with antigen-specific mouse IgA, and an in vivo model using pIgR−/− mice. Secretory IgA targeting the extra-epithelial chlamydial antigen, the major outer membrane protein, significantly reduced infection in vitro by 24% and in vivo by 44%. Conversely, pIgR-mediated delivery of IgA targeting the intra-epithelial inclusion membrane protein A bound to the inclusion but did not reduce infection in vitro or in vivo. Similarly, intra-epithelial IgA targeting the secreted protease Chlamydia protease-like activity factor also failed to reduce infection. Together, these data suggest the importance of pIgR-mediated delivery of IgA targeting extra-epithelial, but not intra-epithelial, chlamydial antigens for protection against a genital tract infection. PMID:24827556

  6. Coexistence of Fabry disease and IgA nephropathy: a report of two cases.

    PubMed

    Yin, G; Wu, Y; Zeng, C-H; Chen, H-P; Liu, Z-H

    2014-12-01

    Coexistence of Fabry disease and IgA nephropathy is rare. Moreover, the coexisting Fabry disease may be unrecognized due to unapparent clinical manifestations. We described two cases with coexisting Fabry disease and IgA nephropathy. The clinicopathological features of these two patients were studied. A 54-year-old male presented with proteinuria, hematuria, and hypertension, and a 33-year-old male presented with proteinuria without clinical signs or family history of Fabry disease. Both of them were diagnosed with IgA nephropathy at admission, whereas Fabry disease was not suspected. Subsequent immunofluorescent study confirmed the diagnosis of IgA nephropathy by showing positive staining for IgA and complement C3 in the mesangium. Meanwhile, light microscopy showed remarkable vacuolation of podocytes with mild mesangial expansion, which was characteristic of Fabry nephropathy. Further examination of toluidine blue-stained semi-thin sections and electron microscopy demonstrated blue bodies and myelin figures in the cytoplasm of podocytes, respectively. The diagnosis of coexisting Fabry disease was finally established based on deficient α-galactosidase A activity in both patients. This case study is an important reminder of the role of kidney biopsy as an indicator of Fabry disease and its rare coexistence with IgA nephropathy.

  7. Determination of IL-1B (rs16944) and IL-6 (rs1800796) genetic polymorphisms in IgA nephropathy in a northwest Chinese Han population.

    PubMed

    Zhang, Daofa; Xie, Maowei; Yang, Xiaohong; Zhang, Yin; Su, Yan; Wang, Yanni; Huang, Haiyang; Han, Hui; Li, Wenning; Fu, Keying; Su, Huiluan; Xu, Wentan; Han, Yeguang; Wang, Ru; Zhang, Pei; Wu, Wei; Huang, Yun; Chen, Daojun; Jin, Tianbo; Wei, Jiali

    2017-09-22

    IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide, but etiology and pathogenesis continue to be poorly understood. Polymorphisms in the cytokine genes may play a role in the etiology and pathogenesis of IgAN. The incidence of different between diverse ethnic groups suggested important genetic influences on its pathogenesis. We genotype 10 single nucleotide polymorphisms (SNPs) in IL-1B and IL-6 gene using Sequenom Mass-ARRAY technology from 417 IgAN patients and 463 healthy controls of the Chinese Han population. We evaluated these SNPs associated with IgAN utilising the chi-square tests and genetic model analysis. We identified that the minor alleles of rs16944 ("A"), rs1800796 ("G") in IL-1B, IL-6 were involved in an increasingly risk of IgAN in allelic model analysis, respectively. The rs16944 in IL-1B and rs1800796 in IL-6 were associated with 1.23-fold (95% CI, 1.02-1.48, P = 0.031) and 1.33-fold (95% CI, 1.11-1.66, P = 0.003) increases in the risk of developing IgAN, respectively. There was only rs1800796 still correlated with IgAN in the allelic model after adjustment by age and gender and the Bonferroni correction. In addition, Haplotype G rs1800796 A rs2069837 G rs2069840 ( P = 0.037) and G rs1800796 A rs2069837 C rs2069840 ( P = 0.042) in IL-6 were considered to be associated with increased IgAN risk. This study verified the IL-6, IL-1B genetic variants polymorphisms contributed to IgAN susceptibility in a Chinese Han population. Although we identified SNPs susceptibility, however, replication studies and functional research are required to confirm the genetic contribution in IgAN.

  8. Determination of IL-1B (rs16944) and IL-6 (rs1800796) genetic polymorphisms in IgA nephropathy in a northwest Chinese Han population

    PubMed Central

    Zhang, Yin; Su, Yan; Wang, Yanni; Huang, Haiyang; Han, Hui; Li, Wenning; Fu, Keying; Su, Huiluan; Xu, Wentan; Han, Yeguang; Wang, Ru; Zhang, Pei; Wu, Wei; Huang, Yun; Chen, Daojun; Jin, Tianbo; Wei, Jiali

    2017-01-01

    IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide, but etiology and pathogenesis continue to be poorly understood. Polymorphisms in the cytokine genes may play a role in the etiology and pathogenesis of IgAN. The incidence of different between diverse ethnic groups suggested important genetic influences on its pathogenesis. We genotype 10 single nucleotide polymorphisms (SNPs) in IL-1B and IL-6 gene using Sequenom Mass-ARRAY technology from 417 IgAN patients and 463 healthy controls of the Chinese Han population. We evaluated these SNPs associated with IgAN utilising the chi-square tests and genetic model analysis. We identified that the minor alleles of rs16944 (“A”), rs1800796 (“G”) in IL-1B, IL-6 were involved in an increasingly risk of IgAN in allelic model analysis, respectively. The rs16944 in IL-1B and rs1800796 in IL-6 were associated with 1.23-fold (95% CI, 1.02-1.48, P = 0.031) and 1.33-fold (95% CI, 1.11-1.66, P = 0.003) increases in the risk of developing IgAN, respectively. There was only rs1800796 still correlated with IgAN in the allelic model after adjustment by age and gender and the Bonferroni correction. In addition, Haplotype Grs1800796A rs2069837G rs2069840 (P = 0.037) and G rs1800796A rs2069837C rs2069840 (P = 0.042) in IL-6were considered to be associated with increased IgAN risk. This study verified the IL-6, IL-1B genetic variants polymorphisms contributed to IgAN susceptibility in a Chinese Han population. Although we identified SNPs susceptibility, however, replication studies and functional research are required to confirm the genetic contribution in IgAN. PMID:29069743

  9. High-affinity monoclonal IgA regulates gut microbiota and prevents colitis in mice.

    PubMed

    Okai, Shinsaku; Usui, Fumihito; Yokota, Shuhei; Hori-I, Yusaku; Hasegawa, Makoto; Nakamura, Toshinobu; Kurosawa, Manabu; Okada, Seiji; Yamamoto, Kazuya; Nishiyama, Eri; Mori, Hiroshi; Yamada, Takuji; Kurokawa, Ken; Matsumoto, Satoshi; Nanno, Masanobu; Naito, Tomoaki; Watanabe, Yohei; Kato, Tamotsu; Miyauchi, Eiji; Ohno, Hiroshi; Shinkura, Reiko

    2016-07-04

    Immunoglobulin A (IgA) is the main antibody isotype secreted into the intestinal lumen. IgA plays a critical role in the defence against pathogens and in the maintenance of intestinal homeostasis. However, how secreted IgA regulates gut microbiota is not completely understood. In this study, we isolated monoclonal IgA antibodies from the small intestine of healthy mouse. As a candidate for an efficient gut microbiota modulator, we selected a W27 IgA, which binds to multiple bacteria, but not beneficial ones such as Lactobacillus casei. W27 could suppress the cell growth of Escherichia coli but not L. casei in vitro, indicating an ability to improve the intestinal environment. Indeed W27 oral treatment could modulate gut microbiota composition and have a therapeutic effect on both lymphoproliferative disease and colitis models in mice. Thus, W27 IgA oral treatment is a potential remedy for inflammatory bowel disease, acting through restoration of host-microbial symbiosis.

  10. Value of isolated IgA anti-β2 -glycoprotein I positivity in the diagnosis of the antiphospholipid syndrome.

    PubMed

    Murthy, Vijaya; Willis, Rohan; Romay-Penabad, Zurina; Ruiz-Limón, Patricia; Martínez-Martínez, Laura A; Jatwani, Shraddha; Jajoria, Praveen; Seif, Alan; Alarcón, Graciela S; Papalardo, Elizabeth; Liu, Jigna; Vilá, Luis M; McGwin, Gerald; McNearney, Terry A; Maganti, Rashmi; Sunkureddi, Prashanth; Parekh, Trisha; Tarantino, Michael; Akhter, Ehtisham; Fang, Hong; Gonzalez, Emilio B; Binder, Walter R; Norman, Gary L; Shums, Zakera; Teodorescu, Marius; Reveille, John D; Petri, Michelle; Pierangeli, Silvia S

    2013-12-01

    To examine the prevalence of isolated IgA anti-β2 -glycoprotein I (anti-β2 GPI) positivity and the association of these antibodies, and a subgroup that bind specifically to domain IV/V of β2 GPI, with clinical manifestations of the antiphospholipid syndrome (APS) in 3 patient groups and to evaluate the pathogenicity of IgA anti-β2 GPI in a mouse model of thrombosis. Patients with systemic lupus erythematosus (SLE) from a multiethnic, multicenter cohort (LUpus in MInorities, NAture versus nurture [LUMINA]) (n = 558), patients with SLE from the Hopkins Lupus Cohort (n = 215), and serum samples referred to the Antiphospholipid Standardization Laboratory (APLS) (n = 5,098) were evaluated. IgA anti-β2 GPI titers and binding to domain IV/V of β2 GPI were examined by enzyme-linked immunosorbent assay (ELISA). CD1 mice were inoculated with purified IgA anti-β2 GPI antibodies, and surgical procedures and ELISAs were performed to evaluate thrombus development and tissue factor (TF) activity. A total of 198 patients were found to be positive for IgA anti-β2 GPI isotype, and 57 patients were positive exclusively for IgA anti-β2 GPI antibodies. Of these, 13 of 23 patients (56.5%) in the LUMINA cohort, 17 of 17 patients (100%) in the Hopkins cohort, and 10 of 17 patients (58.9%) referred to APLS had at least one APS-related clinical manifestation. Fifty-four percent of all the IgA anti-β2 GPI-positive serum samples reacted with domain IV/V of anti-β2 GPI, and 77% of those had clinical features of APS. Isolated IgA anti-β2 GPI positivity was associated with an increased risk of arterial thrombosis (P < 0.001), venous thrombosis (P = 0.015), and all thrombosis (P < 0.001). The association between isolated IgA anti-β2 GPI and arterial thrombosis (P = 0.0003) and all thrombosis (P = 0.0003) remained significant after adjusting for other risk factors for thrombosis. In vivo mouse studies demonstrated that IgA anti-β2 GPI antibodies induced significantly larger thrombi

  11. IgA Vasculitis: Genetics and Clinical and Therapeutic Management.

    PubMed

    González-Gay, Miguel A; López-Mejías, Raquel; Pina, Trinitario; Blanco, Ricardo; Castañeda, Santos

    2018-04-02

    The purpose of the study is to perform an update on the current knowledge on genetics, clinical manifestations, and therapy in immunoglobulin A vasculitis (IgAV) (Henoch-Schönlein purpura). A strong genetic predisposition in individuals with IgAV was confirmed. It was due to the association with the HLA class II region that in people of European background is mainly related to HLA-DRB1*01 allele. Recent reports support the claim that kidney disease is more common in adults than in children with IgAV. The clinical spectrum and outcome of adults with IgAV depends on the age of onset. Relapses are not uncommon in IgAV. The presence of renal impairment or proteinuria excretion exceeding 1 g/24 h at the time of disease diagnosis and the degree of renal damage on the kidney biopsy are the best predictors of end-stage renal failure in adults with IgAV. The levels of urinary IgA at the onset of the disease may predict a poor renal outcome. The use of prednisone does not seem to prevent persistent kidney disease in children with IgAV. No additional benefit of adding cyclophosphamide to glucocorticoids in adults with IgAV was found. Rituximab seems to be a promising therapy in the management of adults with IgAV. In this overview, we focus on the genetics, clinical manifestations, and therapy of IgA vasculitis, emphasizing the main differences in the clinical expression of the disease between children and adults.

  12. Generation and characterization of antibodies specific for caspase-cleaved neo-epitopes: a novel approach

    PubMed Central

    Ai, X; Butts, B; Vora, K; Li, W; Tache-Talmadge, C; Fridman, A; Mehmet, H

    2011-01-01

    Apoptosis research has been significantly aided by the generation of antibodies against caspase-cleaved peptide neo-epitopes. However, most of these antibodies recognize the N-terminal fragment and are specific for the protein in question. The aim of this project was to create antibodies, which could identify caspase-cleaved proteins without a priori knowledge of the cleavage sites or even the proteins themselves. We hypothesized that many caspase-cleavage products might have a common antigenic shape, given that they must all fit into the same active site of caspases. Rabbits were immunized with the eight most prevalent exposed C-terminal tetrapeptide sequences following caspase cleavage. After purification of the antibodies we demonstrated (1) their specificity for exposed C-terminal (but not internal) peptides, (2) their ability to detect known caspase-cleaved proteins from apoptotic cell lysates or supernatants from apoptotic cell culture and (3) their ability to detect a caspase-cleaved protein whose tetrapeptide sequence differs from the eight tetrapeptides used to generate the antibodies. These antibodies have the potential to identify novel neo-epitopes produced by caspase cleavage and so can be used to identify pathway-specific caspase cleavage events in a specific cell type. Additionally this methodology may be applied to generate antibodies against products of other proteases, which have a well-defined and non-promiscuous cleavage activity. PMID:21881607

  13. IgA measurements in over 12 000 Swedish twins reveal sex differential heritability and regulatory locus near CD30L.

    PubMed

    Viktorin, Alexander; Frankowiack, Marcel; Padyukov, Leonid; Chang, Zheng; Melén, Erik; Sääf, Annika; Kull, Inger; Klareskog, Lars; Hammarström, Lennart; Magnusson, Patrik K E

    2014-08-01

    In a broad attempt to improve the understanding of the genetic regulation of serum IgA levels, the heritability was estimated in over 12 000 Swedish twins, and a genome-wide association study was conducted in a subsample of 9617. Using the classical twin model the heritability was found to be significantly larger among females (61%) compared with males (21%), while contribution from shared environment (20%) was only seen for males. By modeling the genetic relationship matrix with IgA levels, we estimate that a substantial proportion (31%) of variance in IgA levels can ultimately be explained by the investigated SNPs. The genome-wide association study revealed significant association to two loci: (i) rs6928791 located on chromosome 6, 22 kb upstream of the gene SAM and SH3 domain containing 1 (SASH1) and (ii) rs13300483 on chromosome 9, situated 12 kb downstream the CD30 ligand (CD30L) encoding gene. The association to rs13300483 was replicated in two additional independent Swedish materials. The heritability of IgA levels is moderate and can partly be attributable to common variation in the CD30L locus. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Meprin A and meprin {alpha} generate biologically functional IL-1{beta} from pro-IL-1{beta}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Herzog, Christian; University of Arkansas for Medical Sciences, Department of Medicine, Little Rock, AR 72205; Haun, Randy S.

    The present study demonstrates that both oligomeric metalloendopeptidase meprin A purified from kidney cortex and recombinant meprin {alpha} are capable of generating biologically active IL-1{beta} from its precursor pro-IL-1{beta}. Amino-acid sequencing analysis reveals that meprin A and meprin {alpha} cleave pro-IL-1{beta} at the His{sup 115}-Asp{sup 116} bond, which is one amino acid N-terminal to the caspase-1 cleavage site and five amino acids C-terminal to the meprin {beta} site. The biological activity of the pro-IL-1{beta} cleaved product produced by meprin A, determined by proliferative response of helper T-cells, was 3-fold higher to that of the IL-1{beta} product produced by meprin {beta}more » or caspase-1. In a mouse model of sepsis induced by cecal ligation puncture that results in elevated levels of serum IL-1{beta}, meprin inhibitor actinonin significantly reduces levels of serum IL-1{beta}. Meprin A and meprin {alpha} may therefore play a critical role in the production of active IL-1{beta} during inflammation and tissue injury.« less

  15. IgA modulates respiratory dysfunction as a sequela to pulmonary chlamydial infection as neonates

    PubMed Central

    Lanka, Gopala Krishna Koundinya; Yu, Jieh-Juen; Gong, Siqi; Gupta, Rishein; Mustafa, Shamimunisa B.; Murthy, Ashlesh K.; Zhong, Guangming; Chambers, James P.; Guentzel, M. Neal; Arulanandam, Bernard P.

    2016-01-01

    Neonatal Chlamydia lung infections are associated with serious sequelae such as asthma and airway hyper-reactivity in children and adults. Our previous studies demonstrated the importance of Th-1 type cytokines, IL-12 and IFN-γ in protection against neonatal pulmonary chlamydial challenge; however, the role of the humoral arm of defense has not been elucidated. We hypothesized that B-cells and IgA, the major mucosal antibody, play a protective role in newborns against development of later life respiratory sequelae to Chlamydia infection. Our studies using neonatal mice revealed that all WT and IgA-deficient (IgA−/−) animals survived a sublethal pulmonary Chlamydia muridarum challenge at one day after birth with similar reduction in bacterial burdens over time. In contrast, all B-cell-deficient (μMT) mice succumbed to infection at the same challenge dose correlating to failure to control bacterial burdens in the lungs. Although IgA may not be important for bacterial clearance, we observed IgA−/− mice displayed greater respiratory dysfunction 5 weeks post challenge. Specifically, comparative respiratory functional analyses revealed a significant shift upward in P–V loops, and higher dynamic resistance in IgA−/− animals. This study provides insight(s) into the protective role of IgA in neonates against pulmonary chlamydial infection induced respiratory pathological sequelae observed later in life. PMID:26755533

  16. Label-free Quantitative Proteomics of Mouse Cerebrospinal Fluid Detects β-Site APP Cleaving Enzyme (BACE1) Protease Substrates In Vivo*

    PubMed Central

    Dislich, Bastian; Wohlrab, Felix; Bachhuber, Teresa; Müller, Stephan A.; Kuhn, Peer-Hendrik; Hogl, Sebastian; Meyer-Luehmann, Melanie; Lichtenthaler, Stefan F.

    2015-01-01

    Analysis of murine cerebrospinal fluid (CSF) by quantitative mass spectrometry is challenging because of low CSF volume, low total protein concentration, and the presence of highly abundant proteins such as albumin. We demonstrate that the CSF proteome of individual mice can be analyzed in a quantitative manner to a depth of several hundred proteins in a robust and simple workflow consisting of single ultra HPLC runs on a benchtop mass spectrometer. The workflow is validated by a comparative analysis of BACE1−/− and wild-type mice using label-free quantification. The protease BACE1 cleaves the amyloid precursor protein (APP) as well as several other substrates and is a major drug target in Alzheimer's disease. We identified a total of 715 proteins with at least 2 unique peptides and quantified 522 of those proteins in CSF from BACE1−/− and wild-type mice. Several proteins, including the known BACE1 substrates APP, APLP1, CHL1 and contactin-2 showed lower abundance in the CSF of BACE1−/− mice, demonstrating that BACE1 substrate identification is possible from CSF. Additionally, ectonucleotide pyrophosphatase 5 was identified as a novel BACE1 substrate and validated in cells using immunoblots and by an in vitro BACE1 protease assay. Likewise, receptor-type tyrosine-protein phosphatase N2 and plexin domain-containing 2 were confirmed as BACE1 substrates by in vitro assays. Taken together, our study shows the deepest characterization of the mouse CSF proteome to date and the first quantitative analysis of the CSF proteome of individual mice. The BACE1 substrates identified in CSF may serve as biomarkers to monitor BACE1 activity in Alzheimer patients treated with BACE inhibitors. PMID:26139848

  17. Fetzima (levomilnacipran), a drug for major depressive disorder as a dual inhibitor for human serotonin transporters and beta-site amyloid precursor protein cleaving enzyme-1.

    PubMed

    Rizvi, Syed Mohd Danish; Shaikh, Sibhghatulla; Khan, Mahiuddin; Biswas, Deboshree; Hameed, Nida; Shakil, Shazi

    2014-01-01

    Pharmacological management of Major Depressive Disorder includes the use of serotonin reuptake inhibitors which targets serotonin transporters (SERT) to increase the synaptic concentrations of serotonin. Beta-site amyloid precursor protein cleaving enzyme-1 (BACE-1) is responsible for amyloid β plaque formation. Hence it is an interesting target for Alzheimer's disease (AD) therapy. This study describes molecular interactions of a new Food and Drug Administration approved antidepressant drug named 'Fetzima' with BACE-1 and SERT. Fetzima is chemically known as levomilnacipran. The study has explored a possible link between the treatment of Depression and AD. 'Autodock 4.2' was used for docking study. The free energy of binding (ΔG) values for 'levomilnacipran-SERT' interaction and 'levomilnacipran-BACE1' interaction were found to be -7.47 and -8.25 kcal/mol, respectively. Levomilnacipran was found to interact with S438, known to be the most important amino acid residue of serotonin binding site of SERT during 'levomilnacipran-SERT' interaction. In the case of 'levomilnacipran-BACE1' interaction, levomilnacipran interacted with two very crucial aspartic acid residues of BACE-1, namely, D32 and D228. These residues are accountable for the cleavage of amyloid precursor protein and the subsequent formation of amyloid β plaques in AD brain. Hence, Fetzima (levomilnacipran) might act as a potent dual inhibitor of SERT and BACE-1 and expected to form the basis of a future dual therapy against depression and AD. It is an established fact that development of AD is associated with Major Depressive Disorder. Therefore, the design of new BACE-1 inhibitors based on antidepressant drug scaffolds would be particularly beneficial.

  18. Giardia muris trophozoite antigenic targets for mouse intestinal IgA antibody.

    PubMed

    Heyworth, M F; Vergara, J A

    1994-02-01

    The aim of this work was to characterize Giardia muris trophozoite proteins that are targets for intestinal anti-trophozoite IgA in G. muris-infected mice. Intestinal secretions were obtained from immunocompetent BALB/c mice that had been infected with G. muris cysts 4-5 weeks previously and from control uninfected BALB/c mice. Flow cytometry of G. muris trophozoites that had been incubated with intestinal secretions and with fluorescein isothiocyanate-conjugated anti-mouse IgA showed that anti-trophozoite IgA was present in intestinal secretions obtained from infected BALB/c mice. By immunoblotting on G. muris trophozoite proteins separated by one-dimensional gel electrophoresis, this IgA recognized at least one trophozoite protein of molecular mass of approximately 80 kDa. The 80-kDa G. muris protein(s) has a molecular mass similar to that described for cysteine-rich surface proteins of the human parasite Giardia lamblia.

  19. A comparison of salivary IgA in children with Down syndrome and their family members.

    PubMed

    Balaji, Karthika; Milne, Trudy J; Drummond, Bernadette K; Cullinan, Mary P; Coates, Dawn E

    2016-07-01

    The aim of this study was to compare total IgA in the whole saliva of children with Down syndrome with levels in sibling and parent groups. IgA measurements were presented as the concentration in saliva (μg/ml) and also adjusted for salivary flow rate (SFR; μg/min). Twenty children with Down syndrome, ten siblings and twenty parents were recruited. Stimulated whole saliva was collected from the participants and SFR calculated. The measurement of salivary IgA (sIgA) was carried out using an indirect competitive Enzyme-Linked Immunosorbent Assay. The difference in the mean SFR between children with Down syndrome, parents and siblings were not statistically significant. The mean salivary concentration of IgA was higher in children with Down syndrome (95.1 μg/ml) compared with siblings (48.3 μg/ml; p=0.004). When adjusted for SFR children with Down syndrome had mean sIgA levels of 98.8 μg/min and the siblings 48.6 μg/min (p=0.008). The children with Down syndrome had sIgA levels similar to those of the parents (92.5 μg/ml; 93.2 μg/min). There was a positive correlation between age and sIgA concentration in the siblings (p=0.008) but not for children with Down syndrome (p=0.363). This suggests that under similar environmental influences, the levels of sIgA in children with Down syndrome are higher than in the siblings, from a very young age. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Multicentric Castleman's disease associated with IgA vasculitis (Henoch-Schönlein purpura) responding well to tocilizumab: a case report.

    PubMed

    Oshima, Yoichi; Hoshino, Junichi; Suwabe, Tatsuya; Hayami, Noriko; Yamanouchi, Masayuki; Sekine, Akinari; Ueno, Toshiharu; Mizuno, Hiroki; Yabuuchi, Junko; Imafuku, Aya; Kawada, Masahiro; Hiramatsu, Rikako; Hasegawa, Eiko; Sawa, Naoki; Takaichi, Kenmei; Hayashi, Nobukazu; Fujii, Takeshi; Ubara, Yoshifumi

    2017-03-01

    A 41-year-old man was referred to our hospital for the evaluation of hypergammaglobulinemia (IgG 2898 mg/dL and IgA 587 mg/dL), inflammation (CRP 6.7 mg/dL and serum interleukin-6 (IL-6) 15.1 ng/L), and anemia (Hb 10.9 mg/dL). Castleman's disease (CD) was diagnosed by axillary lymph node biopsy. Five months later, painful purpura (multiple palpable 5 mm lesions) developed on his legs, gradually spreading to the upper limbs, thighs, and trunk, accompanied by arthralgia of the wrists, ankles, and knees. Skin biopsy revealed leukocytoclastic vasculitis with IgA deposits in dermal vessels. Accordingly, IgA vasculitis (Henoch-Schönlein purpura) was diagnosed. Tocilizumab (an anti-IL-6 receptor antibody) was administered intravenously at 8 mg/kg and treatment was repeated at monthly intervals. His purpura and clinical findings specific to CD improved rapidly. CD is well known to cause various skin lesions. The findings in this case indicate that overproduction of IL-6 contributes to IgA vasculitis (Henoch-Schönlein purpura) as well as to the pathogenesis of CD.

  1. Structural basis for norovirus neutralization by an HBGA blocking human IgA antibody.

    PubMed

    Shanker, Sreejesh; Czakó, Rita; Sapparapu, Gopal; Alvarado, Gabriela; Viskovska, Maria; Sankaran, Banumathi; Atmar, Robert L; Crowe, James E; Estes, Mary K; Prasad, B V Venkataram

    2016-10-04

    Human noroviruses (HuNoVs) cause sporadic and epidemic gastroenteritis worldwide. They are classified into two major genogroups (GI and GII), with each genogroup further divided into multiple genotypes. Susceptibility to these viruses is influenced by genetically determined histo-blood group antigen (HBGA) expression. HBGAs function as cell attachment factors by binding to a surface-exposed region in the protruding (P) domain of the capsid protein. Sequence variations in this region that result in differential HBGA binding patterns and antigenicity are suggested to form a basis for strain diversification. Recent studies show that serum antibodies that block HBGA binding correlate with protection against illness. Although genogroup-dependent variation in HBGA binding specificity is structurally well characterized, an understanding of how antibodies block HBGA binding and how genotypic variations affect such blockade is lacking. Our crystallographic studies of the GI.1 P domain in complex with the Fab fragment of a human IgA monoclonal antibody (IgA 5I2) with HBGA blocking activity show that the antibody recognizes a conformational epitope formed by two surface-exposed loop clusters in the P domain. The antibody engulfs the HBGA binding site but does not affect its structural integrity. An unusual feature of the antigen recognition by IgA 5I2 is the predominant involvement of the CDR light chain 1 in contrast to the commonly observed CDR heavy chain 3, providing a unique perspective into antibody diversity in antigen recognition. Identification of the antigenic site in the P domain shows how genotypic variations might allow escape from antibody neutralization and exemplifies the interplay between antigenicity and HBGA specificity in HuNoV evolution.

  2. Cocoa and cocoa fibre differentially modulate IgA and IgM production at mucosal sites.

    PubMed

    Massot-Cladera, Malen; Franch, Àngels; Pérez-Cano, Francisco J; Castell, Margarida

    2016-05-01

    Previous studies have shown that a 10 % cocoa (C10) diet, containing polyphenols and fibre among others, modifies intestinal and systemic Ig production. The present study aimed at evaluating the impact of C10 on IgA and IgM production in the intestinal and extra-intestinal mucosal compartments, establishing the involvement of cocoa fibre (CF) in such effects. Mechanisms by which C10 intake may affect IgA synthesis in the salivary glands were also studied. To this effect, rats were fed either a standard diet, a diet containing C10, CF or inulin. Intestinal (the gut wash (GW), Peyer's patches (PP) and mesenteric lymph nodes (MLN)) and extra-intestinal (salivary glands) mucosal tissues and blood samples were collected for IgA and IgM quantification. The gene expressions of IgA production- and homing-related molecules were studied in the salivary glands. The C10 diet decreased intestinal IgA and IgM production. Although the CF diet decreased the GW IgA concentration, it increased PP, MLN and serum IgA concentrations. Both the C10 and the CF diets produced a down-regulatory effect on IgA secretion in the extra-intestinal tissues. The C10 diet interacted with the mechanisms involved in IgA synthesis, whereas the CF showed particular effects on the homing and transcytosis of IgA across the salivary glands. Overall, CF was able to up-regulate IgA production in the intestinal-inductor compartments, whereas it down-regulated its production at the mucosal-effector ones. Further studies must be directed to ascertain the mechanisms involved in the effect of particular cocoa components on gut-associated lymphoid tissue.

  3. Potential anti-cholinesterase and β-site amyloid precursor protein cleaving enzyme 1 inhibitory activities of cornuside and gallotannins from Cornus officinalis fruits.

    PubMed

    Bhakta, Himanshu Kumar; Park, Chan Hum; Yokozawa, Takako; Tanaka, Takashi; Jung, Hyun Ah; Choi, Jae Sue

    2017-07-01

    Cholinesterase (ChE) and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitors are promising agents for the treatment of Alzheimer's disease (AD). In the present study, we examined the inhibitory activity of seven compounds isolated from the fruits of Cornus officinalis, cornuside, polymeric proanthocyanidins, 1,2,3-tri-O-galloyl-β-D-glucose, 1,2,3,6-tetra-O-galloyl-β-D-glucose, tellimagrandin I, tellimagrandin II, and isoterchebin, against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and BACE1. All of the compounds displayed concentration-dependent in vitro inhibitory activity toward the ChEs and BACE1. Among them, tellimagrandin II exhibited the best inhibitory activity toward ChEs, whereas the best BACE1 inhibitor was 1,2,3,6-tetra-O-galloyl-β-D-glucose. Isoterchebin and polymeric proanthocyanidins were also significant ChE inhibitors. The kinetic and docking studies demonstrated that all compounds interacted with both the catalytic active sites and the peripheral anionic sites of the ChEs and BACE1. Tellimagrandin II, isoterchebin, and the polymeric proanthocyanidins exhibited concentration-dependent inhibition of peroxynitrite-mediated protein tyrosine nitration. In conclusion, we identified significant ChE and BACE1 inhibitors from Corni Fructus that could have value as new multi-targeted compounds for anti-AD agents.

  4. Production of Furin-cleaved Papillomavirus Pseudovirions and their use for in vitro neutralization assays of L1 or L2-specific antibodies

    PubMed Central

    Wang, Joshua W; Matsui, Ken; Pan, Yuanji; Kwak, Kihyuck; Peng, Shiwen; Kemp, Troy; Pinto, Ligia; Roden, Richard B.S

    2015-01-01

    Immunization with Human Papillomavirus (HPV) L1 virus-like particles or L2 capsid protein elicits neutralizing antibodies that mediate protection. A high throughput and sensitive in vitro neutralization assay is therefore valuable for prophylactic HPV vaccine studies. Over several hours during infection of the genital tract, virions take on a distinct intermediate conformation, including a required furin cleavage of L2 at its N-terminus. This intermediate is an important target for neutralization by L2-specific antibody, but it is very transiently exposed during in vitro infection of most cell lines resulting in insensitive measurement for L2, but not L1-specific neutralizing antibodies. To model this intermediate, we describe a protocol to generate furin-cleaved HPV pseudovirions (fc-PsV) which deliver an encapsidated reporter plasmid to facilitate infectivity measurements. We also describe a protocol for use of fc-PsV in a high throughput in vitro neutralization assay for the sensitive measurement of both L1 and L2-specific neutralizing antibodies. PMID:26237105

  5. Identification of ribozymes within a ribozyme library that efficiently cleave a long substrate RNA.

    PubMed Central

    Campbell, T B; Cech, T R

    1995-01-01

    Positions 2-6 of the substrate-binding internal guide sequence (IGS) of the L-21 Sca I form of the Tetrahymena thermophila intron were mutagenized to produce a GN5 IGS library. Ribozymes within the GN5 library capable of efficient cleavage of an 818-nt human immunodeficiency virus type 1 vif-vpr RNA, at 37 degrees C, were identified by ribozyme-catalyzed guanosine addition to the 3' cleavage product. Three ribozymes (IGS = GGGGCU, GGCUCC, and GUGGCU) within the GN5 library that actively cleaved the long substrate were characterized kinetically and compared to the wild-type ribozyme (GGAGGG) and two control ribozymes (GGAGUC and GGAGAU). The two control ribozymes have specific sites within the long substrate, but were not identified during screening of the library. Under single-turnover conditions, ribozymes GGGGCU, GGCUCC, and GUGGCU cleaved the 818-nt substrate 4- to 200-fold faster than control ribozymes. Short cognate substrates, which should be structureless and therefore accessible to ribozyme binding, were cleaved at similar rates by all ribozymes except GGGGCU, which showed a fourfold rate enhancement. The rate of cleavage of long relative to short substrate under single-turnover conditions suggests that GGCUCC and GUGGCU were identified because of accessibility to their specific cleavage sites within the long substrate (substrate-specific effects), whereas GGGGCU was identified because of an enhanced rate of substrate binding despite a less accessible site in the long substrate. Even though screening was performed with 100-fold excess substrate (relative to total ribozyme), the rate of multiple-turnover catalysis did not contribute to identification of trans-cleaving ribozymes in the GN5 library. PMID:7489519

  6. EF1A1/HSC70 Cooperatively Suppress Brain Endothelial Cell Apoptosis via Regulating JNK Activity.

    PubMed

    Liu, Ying; Jiang, Shu; Yang, Peng-Yuan; Zhang, Yue-Fan; Li, Tie-Jun; Rui, Yao-Cheng

    2016-10-01

    In our previous study, eEF1A1 was identified to be a new target for protecting brain ischemia injury, but the mechanism remains largely unknown. In this study, we screened the downstream cellular protein molecules interacted with eEF1A1 and found mechanism of eEF1A1 in brain ischemia protection. Through co-immunoprecipitation and mass spectrometry for searching the interaction of proteins with eEF1A1 in bEnd3 cells, HSC70 was identified to be a binding protein of eEF1A1, which was further validated by Western blot and immunofluorescence. eEF1A1 or HSC70 knockdown, respectively, increased OGD-induced apoptosis of brain vascular endothelial cells, which was detected by Annexin V-FITC/PI staining. HSC70 or eEF1A1 knockdown enhances phosphorylated JNK, phosphorylation of c-JUN (Ser63, Ser73), cleaved caspase-9, and cleaved caspase-3 expression, which could be rescued by JNK inhibitor. In summary, our data suggest that the presence of chaperone forms of interaction between eEF1A1 and HSC70 in brain vascular endothelial cells, eEF1A1 and HSC70 can play a protective role in the process of ischemic stroke by inhibiting the JNK signaling pathway activation. © 2016 John Wiley & Sons Ltd.

  7. Comparison of combined leflunomide and low-dose corticosteroid therapy with full-dose corticosteroid monotherapy for progressive IgA nephropathy.

    PubMed

    Min, Lulin; Wang, Qin; Cao, Liou; Zhou, Wenyan; Yuan, Jiangzi; Zhang, Minfang; Che, Xiajing; Mou, Shan; Fang, Wei; Gu, Leyi; Zhu, Mingli; Wang, Ling; Yu, Zanzhe; Qian, Jiaqi; Ni, Zhaohui

    2017-07-18

    IgA nephropathy is the most common primary glomerulonephritis and one of the leading causes of end-stage renal disease. We performed a randomized, controlled, prospective, open-label trial to determine whether leflunomide combined with low-dose corticosteroid is safe and effective for the treatment of progressive IgA nephropathy, as compared to full-dose corticosteroid monotherapy. Biopsy-proved primary IgA nephropathy patients with an estimated glomerular filtration rate ≥ 30 ml/min/1.73m2 and proteinuria ≥1.0 g/24h were randomly assigned to receive leflunomide+low-dose corticosteroid (leflunomide group; n = 40) or full-dose corticosteroid (corticosteroids group; n = 45). The primary outcome was renal survival; secondary outcomes were proteinuria and adverse events. After 12 months of treatment and an average follow-up of 88 months, 11.1% vs. 7.5% of patients reached end-stage renal disease and 20% versus 10% of patients had a ≥ 50% increase in serum creatinine in the corticosteroids and leflunomide groups, respectively. Kaplan-Meier analysis did not reveal a between-group difference in these outcomes. Decreases in 24-hour proteinuria were similar in the two groups during the treatment period, but a more marked reduction was observed during follow-up in the leflunomide group. Although the incidence of adverse events was similar in the two groups, serious adverse events were observed only in the corticosteroid group. Thus, leflunomide combined with low-dose corticosteroid is at least as effective as corticosteroid alone for the treatment of progressive IgA nephropathy, and showed a greater reduction of proteinuria during long-term follow-up and fewer severe adverse events.

  8. Biogenesis of non-structural protein 1 (nsp1) and nsp1-mediated type I interferon modulation in arteriviruses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Han, Mingyuan; Kim, Chi Yong; Rowland, Raymond R.R.

    2014-06-15

    Type I interferons (IFNs-α/β) play a key role for the antiviral state of host, and the porcine arterivirus; porcine reproductive and respiratory syndrome virus (PRRSV), has been shown to down-regulate the production of IFNs during infection. Non-structural protein (nsp) 1 of PRRSV has been identified as a viral IFN antagonist, and the nsp1α subunit of nsp1 has been shown to degrade the CREB-binding protein (CBP) and to inhibit the formation of enhanceosome thus resulting in the suppression of IFN production. The study was expanded to other member viruses in the family Arteriviridae: equine arteritis virus (EAV), murine lactate dehydrogenase-elevating virusmore » (LDV), and simian hemorrhagic fever virus (SHFV). While PRRSV–nsp1 and LDV–nsp1 were auto-cleaved to produce the nsp1α and nsp1β subunits, EAV–nsp1 remained uncleaved. SHFV–nsp1 was initially predicted to be cleaved to generate three subunits (nsp1α, nsp1β, and nsp1γ), but only two subunits were generated as SHFV–nsp1αβ and SHFV–nsp1γ. The papain-like cysteine protease (PLP) 1α motif in nsp1α remained inactive for SHFV, and only the PLP1β motif of nsp1β was functional to generate SHFV–nsp1γ subunit. All subunits of arterivirus nsp1 were localized in the both nucleus and cytoplasm, but PRRSV–nsp1β, LDV–nsp1β, EAV–nsp1, and SHFV–nsp1γ were predominantly found in the nucleus. All subunits of arterivirus nsp1 contained the IFN suppressive activity and inhibited both interferon regulatory factor 3 (IRF3) and NF-κB mediated IFN promoter activities. Similar to PRRSV–nsp1α, CBP degradation was evident in cells expressing LDV–nsp1α and SHFV–nsp1γ, but no such degradation was observed for EAV–nsp1. Regardless of CBP degradation, all subunits of arterivirus nsp1 suppressed the IFN-sensitive response element (ISRE)-promoter activities. Our data show that the nsp1-mediated IFN modulation is a common strategy for all arteriviruses but their mechanism of action may

  9. Reishi mushroom Ganoderma lucidum Modulates IgA production and alpha-defensin expression in the rat small intestine.

    PubMed

    Kubota, Atsuhito; Kobayashi, Masaki; Sarashina, Sota; Takeno, Reiko; Okamoto, Keisuke; Narumi, Katsuya; Furugen, Ayako; Suzuki, Yuji; Takahashi, Natsuko; Iseki, Ken

    2018-03-25

    Immunoglobulin A (IgA) secretion and alpha-defensins play a role in the innate immune system to protect against infection. Ganoderma lucidum (W.Curt.: Fr.) P. Karst. (Reishi) is a well-known mushroom in traditional Chinese medicine. This study aimed to determine the effects of Reishi on IgA secretion from Peyer's patch (PP) cells and alpha-defensin-5 (RD-5) and RD-6 expression in the rat small intestine. The rats received an oral injection of 0.5-5mg/kg of Reishi powder (1mL/kg) by sonde. All animals were euthanized 24h after Reishi administration. We examined RD-5, RD-6, and Toll-like receptor (TLR) 4 mRNA levels in the jejunum, ileum, and in Peyer's patches (PP) through quantitative real-time PCR analysis. IgA secretion from PP was measured through enzyme-linked immunosorbent assay of the supernatant after primary culture. Reishi increased IgA secretion in the presence of lipopolysaccharide (LPS) and increased TLR4 mRNA levels, but had no effect on the viability of PP cells. Moreover, Reishi increased RD-5, RD-6, and TLR4 mRNA levels significantly in the ileum in a concentration-dependent manner. Reishi can induce IgA secretion and increase the mRNA levels of RD-5 and RD-6 in the rat small intestine, through a TLR4-dependent pathway. The present results indicate that Reishi might reduce the risk of intestinal infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Clinical efficacy of anti-glycopeptidolipid-core IgA test for diagnosing Mycobacterium avium complex infection in lung.

    PubMed

    Numata, Takanori; Araya, Jun; Yoshii, Yutaka; Shimizu, Kenichiro; Hara, Hiromichi; Nakayama, Katsutoshi; Kuwano, Kazuyoshi

    2015-11-01

    It is difficult to verify the bacteriological diagnosis of Mycobacterium avium complex (MAC) infection. The anti-glycopeptidolipid (GPL)-core IgA antibody test was recently developed as a diagnostic method for MAC pulmonary disease. Only a few studies evaluate its clinical efficacy. We conducted retrospective evaluations of clinical characteristics of patients suspected of MAC infection to explore the usefulness of the anti-GPL-core IgA antibody test. We retrospectively evaluated 296 patients who were suspected to have MAC infection and underwent anti-GPL-core IgA antibody test between March 2013 and July 2014 in Jikei University hospital. A total of 29 patients were diagnosed with 'definite MAC' based on the American Thoracic Society (ATS) criteria with multiple identifications of MAC. On the other hand, 106 patients were diagnosed with other pulmonary diseases than MAC. The sensitivity and specificity of anti-GPL-core IgA antibody test for MAC diagnosis were 58.6% and 98.1%, respectively. The definite MAC group showed no significant differences in strains, treatment history or number of segments involved. The duration of MAC disease in the positive-antibody group was significantly longer than in the negative-antibody group (P = 0.046). A significant increase in the false-negative rate was observed in patients with malignant disease (P = 0.029). The anti-GPL-core IgA antibody test demonstrated high sensitivity and specificity for the diagnosis of MAC infection especially in patients without malignant diseases. © 2015 Asian Pacific Society of Respirology.

  11. Possible mechanism of acute effect of ethanol on intestinal IgA expression in rat.

    PubMed

    Budec, Mirela; Koko, Vesna; Todorović, Vera; Marković, Dragana; Postić, Marija; Drndarević, Neda; Spasić, Andelka; Mitrović, Olivera

    2007-06-01

    The purpose of this study was to investigate the possible mechanism of acute effect of ethanol on IgA expression in rat intestine. To this end, adult female Wistar rats showing diestrus day 1 were treated with (a) ethanol (2 or 4 g/kg, i.p.); (b) N omega-nitro-L-arginine-methyl ester (L-NAME), which inhibits the activity of all isoforms of nitric oxide synthase, (30 mg/kg, s.c.) followed by ethanol 3 h later; and (c) L-NAME (30 mg/kg, s.c.) followed by saline 3 h later. Saline-injected and untreated rats were used as controls. The animals were sacrificed 0.5 h after ethanol administration. Intestinal expression of IgA was evaluated by both immunohistochemistry and Western immunoblotting. Morphometric analysis showed that acute ethanol treatment increased the number of IgA-immunoreactive cells in a dose-dependent manner. Pretreatment with L-NAME abolished this action of alcohol. Injection of L-NAME followed by saline had no influence on the number of IgA+cells. The results, obtained by Western immunoblotting, paralleled our immunohistochemical findings. Taken together, these data suggest that acute effect of ethanol on intestinal IgA might be mediated by endogenous nitric oxide.

  12. Stable 293 T and CHO cell lines expressing cleaved, stable HIV-1 envelope glycoprotein trimers for structural and vaccine studies.

    PubMed

    Chung, Nancy P Y; Matthews, Katie; Kim, Helen J; Ketas, Thomas J; Golabek, Michael; de Los Reyes, Kevin; Korzun, Jacob; Yasmeen, Anila; Sanders, Rogier W; Klasse, Per Johan; Wilson, Ian A; Ward, Andrew B; Marozsan, Andre J; Moore, John P; Cupo, Albert

    2014-04-25

    Recombinant soluble, cleaved HIV-1 envelope glycoprotein SOSIP.664 gp140 trimers based on the subtype A BG505 sequence are being studied structurally and tested as immunogens in animals. For these trimers to become a vaccine candidate for human trials, they would need to be made in appropriate amounts at an acceptable quality. Accomplishing such tasks by transient transfection is likely to be challenging. The traditional way to express recombinant proteins in large amounts is via a permanent cell line, usually of mammalian origin. Making cell lines that produce BG505 SOSIP.664 trimers requires the co-expression of the Furin protease to ensure that the cleavage site between the gp120 and gp41 subunits is fully utilized. We designed a vector capable of expressing Env and Furin, and used it to create Stable 293 T and CHO Flp-In™ cell lines through site-specific recombination. Both lines produce high quality, cleaved trimers at yields of up to 12-15 mg per 1 × 109 cells. Trimer expression at such levels was maintained for up to 30 days (10 passages) after initial seeding and was consistently superior to what could be achieved by transient transfection. Electron microscopy studies confirm that the purified trimers have the same native-like appearance as those derived by transient transfection and used to generate high-resolution structures. They also have appropriate antigenic properties, including the presentation of the quaternary epitope for the broadly neutralizing antibody PGT145. The BG505 SOSIP.664 trimer-expressing cell lines yield proteins of an appropriate quality for structural studies and animal immunogenicity experiments. The methodology is suitable for making similar lines under Good Manufacturing Practice conditions, to produce trimers for human clinical trials. Moreover, any env gene can be incorporated into this vector system, allowing the manufacture of SOSIP trimers from multiple genotypes, either by transient transfection or from stable cell

  13. Blockade of D1 dopaminergic transmission alleviates c-fos induction and cleaved caspase-3 expression in the brains of rat pups exposed to prenatal cocaine or perinatal asphyxia.

    PubMed

    Mitchell, Ellen S; Snyder-Keller, Abigail

    2003-07-01

    Hypoxia due to uterine vasoconstriction may be an important cause of the teratogenic consequences of prenatal cocaine exposure. We used immediate-early gene and cleaved caspase-3 expression patterns to monitor fetal brain regions affected by intrauterine hypoxia and prenatal cocaine and pretreatment with the D1 dopamine receptor antagonist SCH 23390 to determine how much of the induction observed was due to dopamine. Both cocaine binge (3 x 15 mg/kg) and perinatal asphyxia on embryonic day 22 (E22) induced c-fos in the striatum as well as in several other brain regions within 3 h after treatment. Maternal administration of a D1 dopamine antagonist, SCH 23390, before either cocaine or asphyxia exposure dramatically reduced the numbers of Fos-immunoreactive cells in the striatum as well as in many other brain regions. Cells immunoreactive for cleaved caspase-3 expression were more numerous after perinatal asphyxia than after prenatal cocaine exposure in most brain regions 24 h after C-section. SCH 23390 decreased caspase-3 expression after both birth insults, indicating that the increased incidence of apoptosis is related to overactivation of dopaminergic pathways.

  14. A single intranasal immunization with a subunit vaccine formulation induces higher mucosal IgA production than live respiratory syncytial virus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garg, Ravendra

    Respiratory syncytial virus (RSV) causes serious respiratory illness in infants and elderly. RSV infection induces short-lived immunity, which leaves people prone to re-infection. In contrast, the RSV fusion (F) protein formulated with a novel adjuvant (∆F/TriAdj) elicits long term protective immunity. A comparison of RSV-immunized mice to mice vaccinated with a single dose of ∆F/TriAdj showed no difference in IgG1 and IgG2a production; however, local IgA secreting memory B cell development and B cell IgA production were significantly lower in RSV vaccinated mice than in ∆F/TriAdj-immunized mice. This indicates a potential reason as to why long-term immunity is not inducedmore » by RSV infection. The comparison also revealed that germinal center lymphocyte populations were higher in ∆F/TriAdj-vaccinated mice. Furthermore, ∆F/TriAdj induced higher gene expression of activation-induced cytidine deaminase (AID), as well as IL-6, IL-21, TGF-β cytokines, which are key players in IgA class switch recombination, ultimately leading to a sustained long-term memory response. - Highlights: •Immune responses to adjuvanted RSV F protein, ∆F/TriAdj, and RSV were compared. •∆F/TriAdj stimulates more local IgA production than RSV. •∆F/TriAdj induces more local IgA secreting memory B cells than RSV. •Germinal center lymphocyte populations are higher in ∆F/TriAdj-vaccinated mice. •∆F/TriAdj induces higher gene expression of AID, IL-6, IL-21, and TGF-β than RSV.« less

  15. Prevention of Streptococcus mutans colonization by salivary IgA antibodies.

    PubMed

    Gregory, R L; Michalek, S M; Filler, S J; Mestecky, J; McGhee, J R

    1985-01-01

    The levels of salivary and serum IgA, IgG, and IgM antibodies to the seven serotypes (a-g) of Streptococcus mutans were established in 12 laboratory volunteers using a sensitive enzyme-linked immunosorbent assay. Salivary IgA antibody levels to the serotype c organism were significantly lower (P less than 0.005) than antibody levels to the other six serotypes of S. mutans. Similar results were found with a purified S. mutans serotype c carbohydrate. Serum IgG and IgM antibody titers to the serotype c whole cells were significantly higher (P less than 0.05) than to four other S. mutans serotypes (a, e-g). The abilities of S. mutans serotypes c and d to colonize molar tooth surfaces were examined in eight volunteers. S. mutans serotype d was cleared from the tooth surfaces within 24 hr of challenge, whereas S. mutans serotype c was detected in six of the eight volunteers after 2 weeks and in three of eight after 3 weeks. These results provide additional evidence for the role of salivary IgA antibodies in regulating S. mutans infection and suggest that the low levels of salivary IgA antibodies to S. mutans serotype c may contribute to the predominance of this serotype in the U.S. population.

  16. Idiopathic linear IgA bullous dermatosis: prognostic factors based on a case series of 72 adults.

    PubMed

    Gottlieb, J; Ingen-Housz-Oro, S; Alexandre, M; Grootenboer-Mignot, S; Aucouturier, F; Sbidian, E; Tancrede, E; Schneider, P; Regnier, E; Picard-Dahan, C; Begon, E; Pauwels, C; Cury, K; Hüe, S; Bernardeschi, C; Ortonne, N; Caux, F; Wolkenstein, P; Chosidow, O; Prost-Squarcioni, C

    2017-07-01

    Linear IgA bullous dermatosis (LABD) is a clinically and immunologically heterogeneous, subepidermal, autoimmune bullous disease (AIBD), for which the long-term evolution is poorly described. To investigate the clinical and immunological characteristics, follow-up and prognostic factors of adult idiopathic LABD. This retrospective study, conducted in our AIBD referral centre, included adults, diagnosed between 1995 and 2012, with idiopathic LABD, defined as pure or predominant IgA deposits by direct immunofluorescence. Clinical, histological and immunological findings were collected from charts. Standard histology was systematically reviewed, and indirect immunofluorescence (IIF) on salt-split skin (SSS) and immunoblots (IBs) on amniotic membrane extracts using anti-IgA secondary antibodies were performed, when biopsies and sera obtained at diagnosis were available. Prognostic factors for complete remission (CR) were identified using univariate and multivariate analyses. Of the 72 patients included (median age 54 years), 60% had mucous membrane (MM) involvement. IgA IIF on SSS was positive for 21 of 35 patients tested; 15 had epidermal and dermal labellings. Immunoelectron microscopy performed on the biopsies of 31 patients labelled lamina lucida (LL) (26%), lamina densa (23%), anchoring-fibril zone (AFz) (19%) and LL+AFz (23%). Of the 34 IgA IBs, 22 were positive, mostly for LAD-1/LABD97 (44%) and full-length BP180 (33%). The median follow-up was 39 months. Overall, 24 patients (36%) achieved sustained CR, 19 (29%) relapsed and 35% had chronic disease. CR was significantly associated with age > 70 years or no MM involvement. No prognostic immunological factor was identified. Patients with LABD who are < 70 years old and have MM involvement are at risk for chronic evolution. © 2017 British Association of Dermatologists.

  17. Role of maternal elimination diets and human milk IgA in development of cow’s milk allergy in the infants

    PubMed Central

    Järvinen, Kirsi M.; Westfall, Jennifer E.; Seppo, Max S.; James, Aisha K.; Tsuang, Angela J.; Feustel, Paul J.; Sampson, Hugh A.; Berin, Cecilia

    2014-01-01

    Background The role of maternal avoidance diets in the prevention of food allergies is currently under debate. Little is known regarding the effects of such diets on human milk (HM) composition or induction of infant humoral responses. Objective To assess the association of maternal cow’s milk (CM) avoidance during breastfeeding with specific IgA levels in HM and development of cow’s milk allergy (CMA) in infants. Methods We utilized HM and infant serum samples from a prospective birth cohort of 145 dyads. Maternal serum and HM samples were assessed for casein and beta-lactoglobulin (BLG)-specific IgA and IgG by ELISA; 21 mothers prophylactically initiated a strict maternal CM avoidance diet due to a sibling’s history of food allergy and 16 due to atopic eczema or regurgitation/vomiting seen in their infants within the first 3 months of life. Infants’ sera were assessed for casein and BLG-specific IgG, IgA and IgE; CMA was confirmed by an oral food challenge. The impact of HM on BLG uptake was assessed in transcytosis assays utilizing Caco-2 intestinal epithelial cell line. Results Mothers avoiding CM had lower casein- and BLG-specific IgA in HM than mothers with no CM restriction (p=0.019 and p=0.047). Their infants had lower serum casein- and BLG-specific IgG1 (p=0.025 and p<0.001) and BLG-specific IgG4 levels (p=0.037) and their casein- and BLG-specific IgA levels were less often detectable than those with no CM elimination diet (p=0.003 and p=0.007). Lower CM-specific IgG4 and IgA levels in turn were associated with infant CMA. Transcytosis of BLG was impaired by HM with high, but not low levels of specific IgA. Conclusions Maternal CM avoidance was associated with lower levels of mucosal specific IgA levels and development of CMA in infants. Clinical relevance HM IgA may play a role in preventing excessive, uncontrolled food antigen uptake in the gut lumen and thereby in the prevention of CMA. PMID:24164317

  18. Role of maternal elimination diets and human milk IgA in the development of cow's milk allergy in the infants.

    PubMed

    Järvinen, K M; Westfall, J E; Seppo, M S; James, A K; Tsuang, A J; Feustel, P J; Sampson, H A; Berin, C

    2014-01-01

    The role of maternal avoidance diets in the prevention of food allergies is currently under debate. Little is known regarding the effects of such diets on human milk (HM) composition or induction of infant humoral responses. To assess the association of maternal cow's milk (CM) avoidance during breastfeeding with specific IgA levels in HM and development of cow's milk allergy (CMA) in infants. We utilized HM and infant serum samples from a prospective birth cohort of 145 dyads. Maternal serum and HM samples were assessed for casein and beta-lactoglobulin (BLG)-specific IgA and IgG by ELISA; 21 mothers prophylactically initiated a strict maternal CM avoidance diet due to a sibling's history of food allergy and 16 due to atopic eczema or regurgitation/vomiting seen in their infants within the first 3 months of life. Infants' sera were assessed for casein and BLG-specific IgG, IgA and IgE; CMA was confirmed by an oral food challenge. The impact of HM on BLG uptake was assessed in transcytosis assays utilizing Caco-2 intestinal epithelial cell line. Mothers avoiding CM had lower casein- and BLG-specific IgA in HM than mothers with no CM restriction (P = 0.019 and P = 0.047). Their infants had lower serum casein- and BLG-specific IgG(1) (P = 0.025 and P < 0.001) and BLG-specific IgG(4) levels (P = 0.037), and their casein- and BLG-specific IgA levels were less often detectable than those with no CM elimination diet (P = 0.003 and P = 0.007). Lower CM-specific IgG4 and IgA levels in turn were associated with infant CMA. Transcytosis of BLG was impaired by HM with high, but not low levels of specific IgA. Maternal CM avoidance was associated with lower levels of mucosal-specific IgA levels and the development of CMA in infants. HM IgA may play a role in preventing excessive, uncontrolled food antigen uptake in the gut lumen and thereby in the prevention of CMA. © 2013 John Wiley & Sons Ltd.

  19. Defective anti-polysaccharide IgG vaccine responses in IgA deficient mice

    USDA-ARS?s Scientific Manuscript database

    IgA deficient patients often show defects in antibody responses following immunization with polysaccharide vaccines. We now show that IgA-/- mice exhibit specific defects in IgG antibody responses to various polysaccharide vaccines, but not protein vaccines. Defects in anti-polysaccharide IgG resp...

  20. Anal lymphogranuloma venereum infection screening with IgA anti-Chlamydia trachomatis-specific major outer membrane protein serology.

    PubMed

    de Vries, Henry J C; Smelov, Vitaly; Ouburg, Sander; Pleijster, Jolein; Geskus, Ronald B; Speksnijder, Arjen G C L; Fennema, Johannes S A; Morré, Servaas A

    2010-12-01

    Anal lymphogranuloma venereum (LGV) infections, caused by Chlamydia trachomatis biovar L (Ct+/LGV+), are endemic among men who have sex with men (MSM). Anal non-LGV biovar Ct infections (Ct+/LGV-) can be eradicated with 1 week doxycycline, whereas Ct+/LGV+ infections require 3-week doxycycline. To differentiate Ct+/LGV+ from Ct+/LGV- infections, biovar-specific Nucleic Acid Amplification Test (NAAT) are standard, but also expensive and laborious. A chlamydia-specific serological assay could serve as an alternative test. MSM were screened for anal Ct+/LGV+ and Ct+/LGV- infections with a commercial nonspecific NAAT and an in house biovar L-specific NAAT. Serum samples were evaluated with chlamydia-specific anti-Major Outer Membrane Protein (MOMP) and antilipopolysaccharide assays of IgA and IgG classes. Asymptomatic patients were identified as: (1) no anal complaints or (2) no microscopic inflammation (i.e., <10 leucocytes per high power field in anal smears). The best differentiating assay was subsequently evaluated in 100 Ct+/LGV+ and 100 Ct+/LGV- MSM using different cut-off points. The anti-MOMP IgA assay was the most accurate to differentiate Ct+/LGV+ (n = 42) from Ct+/LGV- (n = 19) with 85.7% sensitivity (95% confidence interval [CI], 72.2-93.3) and 84.2% specificity (95% CI, 62.4-94.5), even among asymptomatic patients. In a population comprising 98 Ct+/LGV+ and 105 Ct+/LGV- patients, the anti-MOMP IgA assay scored most accurate when the cut-off point was set to 2.0 with 75.5% (95% CI, 65.8-83.6) sensitivity and 74.3% (95% CI, 64.8-82.3) specificity. The IgA anti-MOMP assay can identify a considerable proportion of the (asymptomatic) anal LGV infections correctly. Yet, biovar L-specific NAAT are still the preferred diagnostic tests in clinical settings.

  1. Predicting Post-transplant Recurrence of IgA Nephropathy: The Importance of Crescents

    PubMed Central

    Avasare, Rupali S.; Rosenstiel, Paul E.; Zaky, Ziad S.; Tsapepas, Demetra; Appel, Gerald B.; Markowitz, Glen S.; Bomback, Andrew S.; Canetta, Pietro A.

    2017-01-01

    Background Most studies assessing the predictors of recurrent IgA nephropathy in the renal allograft have focused on post-transplant features. Identifying high risk pre-transplant features of IgA nephropathy is useful for counseling patients and may help tailor immunosuppression post-transplant. Methods We investigated the pre-transplant clinical and biopsy features of 62 patients with IgAN who received transplants at Columbia University Medical Center from 2001 to 2012 and compared the characteristics and outcomes of patients with IgAN recurrence to those without recurrence. The primary outcome was time to recurrent IgAN. Secondary outcomes were a composite of doubling of creatinine or allograft failure, and recurrent IgAN as a cause of allograft dysfunction. Results Of the 62 patients, 14 had recurrent IgAN in the allograft. Mean time to recurrence was 2.75 years. Those with recurrent disease were younger at time of native kidney biopsy (29 years vs. 41 years, P < 0.0009). Black race and Hispanic ethnicity composed a higher proportion of the recurrent disease group. On multivariable analysis, significant predictors of recurrent IgAN included age at diagnosis (HR 0.911, 95% CI 0.85 to 0.98), burden of crescents on native biopsy (HR 1.21 per 10% increase in crescents, 95% CI 1.00 to 1.47), and allograft rejection (HR 3.59, 95% CI 1.10 to 11.7) Conclusions Features of native IgAN can help predict the risk of recurrent disease in the renal allograft. In particular, immunologically active disease represented by earlier age of onset and greater burden of crescents on native biopsy is more likely to recur post-transplant. PMID:28056461

  2. Clinicopathological Features to Predict Progression of IgA Nephropathy with Mild Proteinuria.

    PubMed

    Chen, Ding; Liu, Jian; Duan, Shuwei; Chen, Pu; Tang, Li; Zhang, Li; Feng, Zhe; Cai, Guangyan; Wu, Jie; Chen, Xiangmei

    2018-03-06

    In the past, little attention has been paid to patients with IgA nephropathy (IgAN) who had minimal proteinuria upon the onset. The aim of this study was to analyze the clinicopathological features and the prognostic factors in patients with IgA nephropathy. Data of patients that had their first renal biopsy in our hospital and were diagnosed with primary IgAN with proteinuria <1 g/d from January 1995 to December 2014 were retrospectively examined. Clinical records of the clinicopathological features, renal function, and proteinuria were collected and investigated. The factors affecting the renal function and proteinuria were analyzed by Cox regression. The predictive efficiencies of clinical and pathological models were evaluated by Harrell concordance index (C-index). A total of 506 patients with IgA nephropathy were included in this study. (1) Baseline proteinuria greater than 0.5 g/d was positively associated with Oxford M, S, and T lesions. eGFR less than 90 mL/min/1.73 m2 were positively associated with Oxford T. (2) In the follow-up with a median of 50 months, 82 patients (16.2%) achieved complete clinical remission (CCR), whereas 54 patients (10.6%) showed an increase in creatinine by more than 50% (not progressing to end-stage renal disease). The cumulative proportion of creatinine increased >50%, and the values obtained by life-table analysis in 10, 15, and 20 years were 15%, 21%, and 22%, respectively. Significant differences were found in baseline age, proteinuria, and Oxford T between the group of creatinine increase >50% and the CCR group. (4) Multivariate COX regression showed that baseline age and proteinuria > 0.5 g/d were independent risk factors of adverse outcome. C-index suggested that the clinical model was more effective than the pathological models in predicting endpoint events. (5) Effect of the mean value during the follow-up on adverse endpoint events: Multivariate COX regression found that the mean proteinuria during follow-up was an

  3. Asparagine endopeptidase cleaves α-synuclein and mediates pathologic activities in Parkinson's disease.

    PubMed

    Zhang, Zhentao; Kang, Seong Su; Liu, Xia; Ahn, Eun Hee; Zhang, Zhaohui; He, Li; Iuvone, P Michael; Duong, Duc M; Seyfried, Nicholas T; Benskey, Matthew J; Manfredsson, Fredric P; Jin, Lingjing; Sun, Yi E; Wang, Jian-Zhi; Ye, Keqiang

    2017-08-01

    Aggregated forms of α-synuclein play a crucial role in the pathogenesis of synucleinopathies such as Parkinson's disease (PD). However, the molecular mechanisms underlying the pathogenic effects of α-synuclein are not completely understood. Here we show that asparagine endopeptidase (AEP) cleaves human α-synuclein, triggers its aggregation and escalates its neurotoxicity, thus leading to dopaminergic neuronal loss and motor impairments in a mouse model. AEP is activated and cleaves human α-synuclein at N103 in an age-dependent manner. AEP is highly activated in human brains with PD, and it fragments α-synuclein, which is found aggregated in Lewy bodies. Overexpression of the AEP-cleaved α-synuclein 1-103 fragment in the substantia nigra induces both dopaminergic neuronal loss and movement defects in mice. In contrast, inhibition of AEP-mediated cleavage of α-synuclein (wild type and A53T mutant) diminishes α-synuclein's pathologic effects. Together, these findings support AEP's role as a key mediator of α-synuclein-related etiopathological effects in PD.

  4. The generation of a 1-hydroxy-2-naphthoate 1,2-dioxygenase by single point mutations of salicylate 1,2-dioxygenase--rational design of mutants and the crystal structures of the A85H and W104Y variants.

    PubMed

    Ferraroni, Marta; Steimer, Lenz; Matera, Irene; Bürger, Sibylle; Scozzafava, Andrea; Stolz, Andreas; Briganti, Fabrizio

    2012-12-01

    Key amino acid residues of the salicylate 1,2-dioxygenase (SDO), an iron (II) class III ring cleaving dioxygenase from Pseudaminobacter salicylatoxidans BN12, were selected, based on amino acid sequence alignments and structural analysis of the enzyme, and modified by site-directed mutagenesis to obtain variant forms with altered catalytic properties. SDO shares with 1-hydroxy-2-naphthoate dioxygenase (1H2NDO) its unique ability to oxidatively cleave monohydroxylated aromatic compounds. Nevertheless SDO is more versatile with respect to 1H2NDO and other known gentisate dioxygenases (GDOs) because it cleaves not only gentisate and 1-hydroxy-2-naphthoate (1H2NC) but also salicylate and substituted salicylates. Several enzyme variants of SDO were rationally designed to simulate 1H2NDO. The basic kinetic parameters for the SDO mutants L38Q, M46V, A85H and W104Y were determined. The enzyme variants L38Q, M46V, A85H demonstrated higher catalytic efficiencies toward 1-hydroxy-2-naphthoate (1H2NC) compared to gentisate. Remarkably, the enzyme variant A85H effectively cleaved 1H2NC but did not oxidize gentisate at all. The W104Y SDO mutant exhibited reduced reaction rates for all substrates tested. The crystal structures of the A85H and W104Y variants were solved and analyzed. The substitution of Ala85 with a histidine residue caused significant changes in the orientation of the loop containing this residue which is involved in the active site closing upon substrate binding. In SDO A85H this specific loop shifts away from the active site and thus opens the cavity favoring the binding of bulkier substrates. Since this loop also interacts with the N-terminal residues of the vicinal subunit, the structure and packing of the holoenzyme might be also affected. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. First demonstration of cerebrospinal fluid and plasma A beta lowering with oral administration of a beta-site amyloid precursor protein-cleaving enzyme 1 inhibitor in nonhuman primates.

    PubMed

    Sankaranarayanan, Sethu; Holahan, Marie A; Colussi, Dennis; Crouthamel, Ming-Chih; Devanarayan, Viswanath; Ellis, Joan; Espeseth, Amy; Gates, Adam T; Graham, Samuel L; Gregro, Allison R; Hazuda, Daria; Hochman, Jerome H; Holloway, Katharine; Jin, Lixia; Kahana, Jason; Lai, Ming-tain; Lineberger, Janet; McGaughey, Georgia; Moore, Keith P; Nantermet, Philippe; Pietrak, Beth; Price, Eric A; Rajapakse, Hemaka; Stauffer, Shaun; Steinbeiser, Melissa A; Seabrook, Guy; Selnick, Harold G; Shi, Xiao-Ping; Stanton, Matthew G; Swestock, John; Tugusheva, Katherine; Tyler, Keala X; Vacca, Joseph P; Wong, Jacky; Wu, Guoxin; Xu, Min; Cook, Jacquelynn J; Simon, Adam J

    2009-01-01

    beta-Site amyloid precursor protein (APP)-cleaving enzyme (BACE) 1 cleavage of amyloid precursor protein is an essential step in the generation of the potentially neurotoxic and amyloidogenic A beta 42 peptides in Alzheimer's disease. Although previous mouse studies have shown brain A beta lowering after BACE1 inhibition, extension of such studies to nonhuman primates or man was precluded by poor potency, brain penetration, and pharmacokinetics of available inhibitors. In this study, a novel tertiary carbinamine BACE1 inhibitor, tertiary carbinamine (TC)-1, was assessed in a unique cisterna magna ported rhesus monkey model, where the temporal dynamics of A beta in cerebrospinal fluid (CSF) and plasma could be evaluated. TC-1, a potent inhibitor (IC(50) approximately 0.4 nM), has excellent passive membrane permeability, low susceptibility to P-glycoprotein transport, and lowered brain A beta levels in a mouse model. Intravenous infusion of TC-1 led to a significant but transient lowering of CSF and plasma A beta levels in conscious rhesus monkeys because it underwent CYP3A4-mediated metabolism. Oral codosing of TC-1 with ritonavir, a potent CYP3A4 inhibitor, twice daily over 3.5 days in rhesus monkeys led to sustained plasma TC-1 exposure and a significant and sustained reduction in CSF sAPP beta, A beta 40, A beta 42, and plasma A beta 40 levels. CSF A beta 42 lowering showed an EC(50) of approximately 20 nM with respect to the CSF [TC-1] levels, demonstrating excellent concordance with its potency in a cell-based assay. These results demonstrate the first in vivo proof of concept of CSF A beta lowering after oral administration of a BACE1 inhibitor in a nonhuman primate.

  6. Allergenic proteases cleave the chemokine CX3CL1 directly from the surface of airway epithelium and augment the effect of rhinovirus.

    PubMed

    Loxham, M; Smart, D E; Bedke, N J; Smithers, N P; Filippi, I; Blume, C; Swindle, E J; Tariq, K; Howarth, P H; Holgate, S T; Davies, D E

    2018-03-01

    CX3CL1 has been implicated in allergen-induced airway CD4 + T-lymphocyte recruitment in asthma. As epidemiological evidence supports a viral infection-allergen synergy in asthma exacerbations, we postulated that rhinovirus (RV) infection in the presence of allergen augments epithelial CX3CL1 release. Fully differentiated primary bronchial epithelial cultures were pretreated apically with house dust mite (HDM) extract and infected with rhinovirus-16 (RV16). CX3CL1 was measured by enzyme-linked immunosorbent assay and western blotting, and shedding mechanisms assessed using inhibitors, protease-activated receptor-2 (PAR-2) agonist, and recombinant CX3CL1-expressing HEK293T cells. Basolateral CX3CL1 release was unaffected by HDM but stimulated by RV16; inhibition by fluticasone or GM6001 implicated nuclear factor-κB and ADAM (A Disintegrin and Metalloproteinase) sheddases. Conversely, apical CX3CL1 shedding was stimulated by HDM and augmented by RV16. Although fluticasone or GM6001 reduced RV16+HDM-induced apical CX3CL1 release, heat inactivation or cysteine protease inhibition completely blocked CX3CL1 shedding. The HDM effect was via enzymatic cleavage of CX3CL1, not PAR-2 activation, yielding a product mitogenic for smooth muscle cells. Extracts of Alternaria fungus caused similar CX3CL1 shedding. We have identified a novel mechanism whereby allergenic proteases cleave CX3CL1 from the apical epithelial surface to yield a biologically active product. RV16 infection augmented HDM-induced CX3CL1 shedding-this may contribute to synergy between allergen exposure and RV infection in triggering asthma exacerbations and airway remodeling.

  7. Reverse enzyme-linked immunosorbent assay using monoclonal antibodies against SAG1-related sequence, SAG2A, and p97 antigens from Toxoplasma gondii to detect specific immunoglobulin G (IgG), IgM, and IgA antibodies in human sera.

    PubMed

    Carvalho, Fernando R; Silva, Deise A O; Cunha-Júnior, Jair P; Souza, Maria A; Oliveira, Taísa C; Béla, Samantha R; Faria, Gabriele G; Lopes, Carolina S; Mineo, José R

    2008-08-01

    The present study aimed to evaluate the performance of three monoclonal antibodies (MAbs) in reverse enzyme-linked immunosorbent assays (ELISAs) for detecting immunoglobulin G (IgG), IgM, and IgA antibodies against Toxoplasma gondii in 175 serum samples from patients at different stages of T. gondii infection, as defined by both serological and clinical criteria, as follows: recent (n = 45), transient (n = 40), and chronic (n = 55) infection as well as seronegative subjects (n = 35). The results were compared with those obtained by indirect ELISA using soluble Toxoplasma total antigen (STAg). Our data demonstrated that MAb A3A4 recognizes a conformational epitope in SAG1-related-sequence (SRS) antigens, while A4D12 and 1B8 recognize linear epitopes defined as SAG2A surface antigen and p97 cytoplasmatic antigen, respectively. Reverse ELISA for IgG with A3A4 or A4D12 MAbs was highly correlated with indirect ELISA for anti-STAg IgG, whereas only A4D12 reverse ELISA showed high correlation with indirect ELISA for IgM and IgA isotypes. To our knowledge, this is the first report analyzing the performance of a reverse ELISA for simultaneous detection of IgG, IgM, and IgA isotypes active toward native SAG2A, SRS, and p97 molecules from STAg, using a panel of human sera from patients with recent and chronic toxoplasmosis. Thus, reverse ELISA based on the capture of native SAG2A and SRS antigens of STAg by MAbs could be an additional approach for strengthening the helpfulness of serological tests assessing the stage of infection, particularly in combination with highly sensitive and specific assays that are frequently used nowadays for diagnosis of toxoplasmosis during pregnancy or congenital infection in newborns.

  8. Antibody-Mediated Internalization of Infectious HIV-1 Virions Differs among Antibody Isotypes and Subclasses.

    PubMed

    Tay, Matthew Zirui; Liu, Pinghuang; Williams, LaTonya D; McRaven, Michael D; Sawant, Sheetal; Gurley, Thaddeus C; Xu, Thomas T; Dennison, S Moses; Liao, Hua-Xin; Chenine, Agnès-Laurence; Alam, S Munir; Moody, M Anthony; Hope, Thomas J; Haynes, Barton F; Tomaras, Georgia D

    2016-08-01

    Emerging data support a role for antibody Fc-mediated antiviral activity in vaccine efficacy and in the control of HIV-1 replication by broadly neutralizing antibodies. Antibody-mediated virus internalization is an Fc-mediated function that may act at the portal of entry whereby effector cells may be triggered by pre-existing antibodies to prevent HIV-1 acquisition. Understanding the capacity of HIV-1 antibodies in mediating internalization of HIV-1 virions by primary monocytes is critical to understanding their full antiviral potency. Antibody isotypes/subclasses differ in functional profile, with consequences for their antiviral activity. For instance, in the RV144 vaccine trial that achieved partial efficacy, Env IgA correlated with increased risk of HIV-1 infection (i.e. decreased vaccine efficacy), whereas V1-V2 IgG3 correlated with decreased risk of HIV-1 infection (i.e. increased vaccine efficacy). Thus, understanding the different functional attributes of HIV-1 specific IgG1, IgG3 and IgA antibodies will help define the mechanisms of immune protection. Here, we utilized an in vitro flow cytometric method utilizing primary monocytes as phagocytes and infectious HIV-1 virions as targets to determine the capacity of Env IgA (IgA1, IgA2), IgG1 and IgG3 antibodies to mediate HIV-1 infectious virion internalization. Importantly, both broadly neutralizing antibodies (i.e. PG9, 2G12, CH31, VRC01 IgG) and non-broadly neutralizing antibodies (i.e. 7B2 mAb, mucosal HIV-1+ IgG) mediated internalization of HIV-1 virions. Furthermore, we found that Env IgG3 of multiple specificities (i.e. CD4bs, V1-V2 and gp41) mediated increased infectious virion internalization over Env IgG1 of the same specificity, while Env IgA mediated decreased infectious virion internalization compared to IgG1. These data demonstrate that antibody-mediated internalization of HIV-1 virions depends on antibody specificity and isotype. Evaluation of the phagocytic potency of vaccine

  9. Antibody-Mediated Internalization of Infectious HIV-1 Virions Differs among Antibody Isotypes and Subclasses

    PubMed Central

    McRaven, Michael D; Sawant, Sheetal; Gurley, Thaddeus C; Xu, Thomas T.; Dennison, S. Moses; Liao, Hua-Xin; Chenine, Agnès-Laurence; Alam, S. Munir; Haynes, Barton F.; Tomaras, Georgia D.

    2016-01-01

    Emerging data support a role for antibody Fc-mediated antiviral activity in vaccine efficacy and in the control of HIV-1 replication by broadly neutralizing antibodies. Antibody-mediated virus internalization is an Fc-mediated function that may act at the portal of entry whereby effector cells may be triggered by pre-existing antibodies to prevent HIV-1 acquisition. Understanding the capacity of HIV-1 antibodies in mediating internalization of HIV-1 virions by primary monocytes is critical to understanding their full antiviral potency. Antibody isotypes/subclasses differ in functional profile, with consequences for their antiviral activity. For instance, in the RV144 vaccine trial that achieved partial efficacy, Env IgA correlated with increased risk of HIV-1 infection (i.e. decreased vaccine efficacy), whereas V1-V2 IgG3 correlated with decreased risk of HIV-1 infection (i.e. increased vaccine efficacy). Thus, understanding the different functional attributes of HIV-1 specific IgG1, IgG3 and IgA antibodies will help define the mechanisms of immune protection. Here, we utilized an in vitro flow cytometric method utilizing primary monocytes as phagocytes and infectious HIV-1 virions as targets to determine the capacity of Env IgA (IgA1, IgA2), IgG1 and IgG3 antibodies to mediate HIV-1 infectious virion internalization. Importantly, both broadly neutralizing antibodies (i.e. PG9, 2G12, CH31, VRC01 IgG) and non-broadly neutralizing antibodies (i.e. 7B2 mAb, mucosal HIV-1+ IgG) mediated internalization of HIV-1 virions. Furthermore, we found that Env IgG3 of multiple specificities (i.e. CD4bs, V1-V2 and gp41) mediated increased infectious virion internalization over Env IgG1 of the same specificity, while Env IgA mediated decreased infectious virion internalization compared to IgG1. These data demonstrate that antibody-mediated internalization of HIV-1 virions depends on antibody specificity and isotype. Evaluation of the phagocytic potency of vaccine

  10. Poly(ADP-ribose) polymerase-1 (Parp-1)-deficient mice demonstrate abnormal antibody responses

    PubMed Central

    Ambrose, Helen E; Willimott, Shaun; Beswick, Richard W; Dantzer, Françoise; de Murcia, Josiane Ménissier; Yelamos, José; Wagner, Simon D

    2009-01-01

    Poly(ADP-ribosylation) of acceptor proteins is an epigenetic modification involved in DNA strand break repair, recombination and transcription. Here we provide evidence for the involvement of poly(ADP-ribose) polymerase-1 (Parp-1) in antibody responses. Parp-1−/− mice had increased numbers of T cells and normal numbers of total B cells. Marginal zone B cells were mildly reduced in number, and numbers of follicular B cells were preserved. There were abnormal levels of basal immunoglobulins, with reduced levels of immunoglobulin G2a (IgG2a) and increased levels of IgA and IgG2b. Analysis of specific antibody responses showed that T cell-independent responses were normal but T cell-dependent responses were markedly reduced. Germinal centres were normal in size and number. In vitro purified B cells from Parp-1−/− mice proliferated normally and showed normal IgM secretion, decreased switching to IgG2a but increased IgA secretion. Collectively our results demonstrate that Parp-1 has essential roles in normal T cell-dependent antibody responses and the regulation of isotype expression. We speculate that Parp-1 forms a component of the protein complex involved in resolving the DNA double-strand breaks that occur during class switch recombination. PMID:18778284

  11. Intramuscular Priming and Intranasal Boosting Induce Strong Genital Immunity Through Secretory IgA in Minipigs Infected with Chlamydia trachomatis

    PubMed Central

    Lorenzen, Emma; Follmann, Frank; Bøje, Sarah; Erneholm, Karin; Olsen, Anja Weinreich; Agerholm, Jørgen Steen; Jungersen, Gregers; Andersen, Peter

    2015-01-01

    International efforts in developing a vaccine against Chlamydia trachomatis have highlighted the need for novel immunization strategies for the induction of genital immunity. In this study, we evaluated an intramuscular (IM) prime/intranasal boost vaccination strategy in a Göttingen Minipig model with a reproductive system very similar to humans. The vaccine was composed of C. trachomatis subunit antigens formulated in the Th1/Th17 promoting CAF01 adjuvant. IM priming immunizations with CAF01 induced a significant cell-mediated interferon gamma and interleukin 17A response and a significant systemic high-titered neutralizing IgG response. Following genital challenge, intranasally boosted groups mounted an accelerated, highly significant genital IgA response that correlated with enhanced bacterial clearance on day 3 post infection. By detecting antigen-specific secretory component (SC), we showed that the genital IgA was locally produced in the genital mucosa. The highly significant inverse correlation between the vaginal IgA SC response and the chlamydial load suggests that IgA in the minipig model is involved in protection against C. trachomatis. This is important both for our understanding of protective immunity and future vaccination strategies against C. trachomatis and genital pathogens in general. PMID:26734002

  12. Comparison of mucosal lining fluid sampling methods and influenza-specific IgA detection assays for use in human studies of influenza immunity.

    PubMed

    de Silva, Thushan I; Gould, Victoria; Mohammed, Nuredin I; Cope, Alethea; Meijer, Adam; Zutt, Ilse; Reimerink, Johan; Kampmann, Beate; Hoschler, Katja; Zambon, Maria; Tregoning, John S

    2017-10-01

    We need greater understanding of the mechanisms underlying protection against influenza virus to develop more effective vaccines. To do this, we need better, more reproducible methods of sampling the nasal mucosa. The aim of the current study was to compare levels of influenza virus A subtype-specific IgA collected using three different methods of nasal sampling. Samples were collected from healthy adult volunteers before and after LAIV immunization by nasal wash, flocked swabs and Synthetic Absorptive Matrix (SAM) strips. Influenza A virus subtype-specific IgA levels were measured by haemagglutinin binding ELISA or haemagglutinin binding microarray and the functional response was assessed by microneutralization. Nasosorption using SAM strips lead to the recovery of a more concentrated sample of material, with a significantly higher level of total and influenza H1-specific IgA. However, an equivalent percentage of specific IgA was observed with all sampling methods when normalized to the total IgA. Responses measured using a recently developed antibody microarray platform, which allows evaluation of binding to multiple influenza strains simultaneously with small sample volumes, were compared to ELISA. There was a good correlation between ELISA and microarray values. Material recovered from SAM strips was weakly neutralizing when used in an in vitro assay, with a modest correlation between the level of IgA measured by ELISA and neutralization, but a greater correlation between microarray-measured IgA and neutralizing activity. In conclusion we have tested three different methods of nasal sampling and show that flocked swabs and novel SAM strips are appropriate alternatives to traditional nasal washes for assessment of mucosal influenza humoral immunity. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Serum concentrations of IgG, IgA, and IgM in retired racing Greyhound dogs.

    PubMed

    Clemente, Mónica; Marín, Liliana; Iazbik, M Cristina; Couto, C Guillermo

    2010-12-01

    Greyhound dogs have significant physiologic, hematologic, and biochemical differences when compared with other breeds, including significantly lower serum globulin concentration owing to decreases in the α- and β-globulin fractions. The specific proteins that account for differences in globulin concentrations are not known, but IgA and IgM, both β-globulins, are potential candidates. The aims of this study were to measure serum IgG, IgA, and IgM in clinically healthy retired racing Greyhounds and compare the results with those of age- and sex-matched non-Greyhound dogs. Study animals included 25 Greyhound and 20 non-Greyhound dogs. Total protein, albumin, and total globulin concentrations were determined. IgG, IgA, and IgM concentrations were measured using a commercially available radial immunodiffusion kit. The Student t-test assuming equal variances was used to compare concentrations of immunoglobulins between groups. Serum concentrations of IgA and IgM in Greyhounds (IgA=49±20 mg/dL; IgM=132±47 mg/dL) were significantly lower than concentrations in non-Greyound dogs (IgA=70±39 mg/dL; Ig M=212±78 mg/dL). Concentrations of IgG did not differ between groups. Mean serum IgA and IgM concentrations in Greyhounds were lower than those in non-Greyhound dogs. This may contribute to low serum concentrations of β-globulins in Greyhounds. Specific reference intervals are recommended for Greyhounds to avoid possible misdiagnosis of IgA or IgM deficiency. ©2010 American Society for Veterinary Clinical Pathology.

  14. Isotype- and subclass-specific responses to infection and reinfection with parainfluenza-3 virus: comparison of the diagnostic potential of ELISAs detecting seroconversion and specific IgM and IgA.

    PubMed

    Graham, D A; Mawhinney, K A; German, A; Foster, J C; Adair, B M; Merza, M

    1999-03-01

    Isotype- and subclass-specific indirect enzyme-linked immunosorbent assays were developed to detect parainfluenza-3 virus-specific IgG1, IgG2, IgM, and IgA responses. Sera were treated with protein G-agarose prior to testing for specific IgM and IgA to eliminate the possibility of false-positive results due to IgM-rheumatoid factor and to remove interisotypic competition due to specific IgG. IgM and IgA absorbance values were expressed as a percentage of the absorbance values of positive reference sera included on each plate (S/P%), and respective positive/negative threshold values of 15.0% and 28.0% were determined. The mean interval between experimental infection of 3 calves and initial detection of specific IgG1 and IgG2 responses was 8.0 and 9.3 days respectively, rising rapidly to an initial plateau 13.7 and 11.0 days postinfection (dpi). Reinfection of these calves at 30 dpi resulted in further rapid increases, with higher plateau values reached 13.0 (IgG1) and 13.7 (IgG2) days later. The mean interval between infection and the first positive IgM and IgA responses was 6.7 and 12.3 days, respectively. IgM S/P% values peaked at 13.0 dpi, with all 3 calves showing a secondary anamnestic response to reinfection, peaking 4.7 days later. The IgA response to initial infection was weak, with only 2 calves showing an obvious peak response at 15.0 dpi. A strong anamnestic IgA response to reinfection occurred in 2 calves, with a peak response 9.5 days later. Apparent biphasic and triphasic IgM and IgA responses were evident in some calves. Acute and convalescent serum samples from 80 calves involved in 17 outbreaks of respiratory disease were tested for specific IgM and IgA. Positive IgM results were detected in 15 outbreaks, with 71 sera from 44 calves testing positive. Although IgA-positive results were detected in the same 15 outbreaks, only 42 sera from 31 calves were positive. In a previous study, seroconversion was detected in 21 of these calves from 10 outbreaks

  15. Comparison of methods for profiling O-glycosylation: Human Proteome Organisation Human Disease Glycomics/Proteome Initiative multi-institutional study of IgA1.

    PubMed

    Wada, Yoshinao; Dell, Anne; Haslam, Stuart M; Tissot, Bérangère; Canis, Kévin; Azadi, Parastoo; Bäckström, Malin; Costello, Catherine E; Hansson, Gunnar C; Hiki, Yoshiyuki; Ishihara, Mayumi; Ito, Hiromi; Kakehi, Kazuaki; Karlsson, Niclas; Hayes, Catherine E; Kato, Koichi; Kawasaki, Nana; Khoo, Kay-Hooi; Kobayashi, Kunihiko; Kolarich, Daniel; Kondo, Akihiro; Lebrilla, Carlito; Nakano, Miyako; Narimatsu, Hisashi; Novak, Jan; Novotny, Milos V; Ohno, Erina; Packer, Nicolle H; Palaima, Elizabeth; Renfrow, Matthew B; Tajiri, Michiko; Thomsson, Kristina A; Yagi, Hirokazu; Yu, Shin-Yi; Taniguchi, Naoyuki

    2010-04-01

    The Human Proteome Organisation Human Disease Glycomics/Proteome Initiative recently coordinated a multi-institutional study that evaluated methodologies that are widely used for defining the N-glycan content in glycoproteins. The study convincingly endorsed mass spectrometry as the technique of choice for glycomic profiling in the discovery phase of diagnostic research. The present study reports the extension of the Human Disease Glycomics/Proteome Initiative's activities to an assessment of the methodologies currently used for O-glycan analysis. Three samples of IgA1 isolated from the serum of patients with multiple myeloma were distributed to 15 laboratories worldwide for O-glycomics analysis. A variety of mass spectrometric and chromatographic procedures representative of current methodologies were used. Similar to the previous N-glycan study, the results convincingly confirmed the pre-eminent performance of MS for O-glycan profiling. Two general strategies were found to give the most reliable data, namely direct MS analysis of mixtures of permethylated reduced glycans in the positive ion mode and analysis of native reduced glycans in the negative ion mode using LC-MS approaches. In addition, mass spectrometric methodologies to analyze O-glycopeptides were also successful.

  16. Cleaving the Halqeh-ye-nur diamonds: a dynamic fracture analysis.

    PubMed

    Atkinson, Colin; Martineau, Philip M; Khan, Rizwan U A; Field, John E; Fisher, David; Davies, Nick M; Samartseva, Julia V; Putterman, Seth J; Hird, Jonathan R

    2015-03-28

    The degree of surface roughness and clarity with which a surface in a brittle material can be formed via fracture is known to be related to the speed of the propagating crack. Cracks traversing a brittle material at low speed produce very smooth surfaces, while those propagating faster create less reflective and rough surfaces (Buehler MJ, Gao H. 2006 Nature 439, 307-310 (doi:10.1038/nature04408)). The elastic wave speeds (c(l)≈18 000 m s(-1), c(s)≈11 750 m s(-1)) in diamond are fast (Willmott GR, Field JE. 2006 Phil. Mag. 86, 4305-4318 (doi:10.1080/14786430500482336)) and present a particular problem in creating smooth surfaces during the cleaving of diamond-a routine operation in the fashioning of diamonds for gemstone purposes--as the waves are reflected from the boundaries of the material and can add a tensile component to the propagating crack tip causing the well-known cleavage steps observed on diamond surfaces (Field JE. 1971 Contemp. Phys. 12, 1-31 (doi:10.1080/00107517108205103); Field JE. 1979 Properties of diamond, 1st edn, Academic Press; Wilks EM. 1958 Phil. Mag. 3, 1074-1080 (doi:10.1080/14786435808237036)). Here we report an analysis of two diamonds, having large dimensions and high aspect ratio, which from a gemological analysis are shown to have been cleaved from the same 200 carat specimen. A methodology for their manufacture is calculated by an analysis of a model problem. This takes into account the effect of multiple reflections from the sample boundaries. It is suggested that the lapidary had an intuitive guide to how to apply the cleavage force in order to control the crack speed. In particular, it is shown that it is likely that this technique caused the fracture to propagate at a lower speed. The sacrifice of a large diamond with the intention of creating thin plates, rather than a faceted gemstone, demonstrates how symbolism and beliefs associated with gemstones have changed over the centuries (Harlow GE. 1998 The nature

  17. Cleaving the Halqeh-ye-nur diamonds: a dynamic fracture analysis

    PubMed Central

    Atkinson, Colin; Martineau, Philip M.; Khan, Rizwan U. A.; Field, John E.; Fisher, David; Davies, Nick M.; Samartseva, Julia V.; Putterman, Seth J.; Hird, Jonathan R.

    2015-01-01

    The degree of surface roughness and clarity with which a surface in a brittle material can be formed via fracture is known to be related to the speed of the propagating crack. Cracks traversing a brittle material at low speed produce very smooth surfaces, while those propagating faster create less reflective and rough surfaces (Buehler MJ, Gao H. 2006 Nature 439, 307–310 (doi:10.1038/nature04408)). The elastic wave speeds (cl≈18 000 m s−1, cs≈11 750 m s−1) in diamond are fast (Willmott GR, Field JE. 2006 Phil. Mag. 86, 4305–4318 (doi:10.1080/14786430500482336)) and present a particular problem in creating smooth surfaces during the cleaving of diamond—a routine operation in the fashioning of diamonds for gemstone purposes—as the waves are reflected from the boundaries of the material and can add a tensile component to the propagating crack tip causing the well-known cleavage steps observed on diamond surfaces (Field JE. 1971 Contemp. Phys. 12, 1–31 (doi:10.1080/00107517108205103); Field JE. 1979 Properties of diamond, 1st edn, Academic Press; Wilks EM. 1958 Phil. Mag. 3, 1074–1080 (doi:10.1080/14786435808237036)). Here we report an analysis of two diamonds, having large dimensions and high aspect ratio, which from a gemological analysis are shown to have been cleaved from the same 200 carat specimen. A methodology for their manufacture is calculated by an analysis of a model problem. This takes into account the effect of multiple reflections from the sample boundaries. It is suggested that the lapidary had an intuitive guide to how to apply the cleavage force in order to control the crack speed. In particular, it is shown that it is likely that this technique caused the fracture to propagate at a lower speed. The sacrifice of a large diamond with the intention of creating thin plates, rather than a faceted gemstone, demonstrates how symbolism and beliefs associated with gemstones have changed over the centuries (Harlow GE. 1998 The

  18. IgA, IgM and IgG anti-M. leprae antibodies in babies of leprosy mothers during the first 2 years of life.

    PubMed Central

    Melsom, R; Harboe, M; Duncan, M E

    1982-01-01

    IgA, IgM and IgG anti-M. leprae antibody activity was estimated by solid phase radioimmunoassay in repeated serum samples from cord sera to sera taken 2 years after birth from 29 babies of mothers with lepromatous leprosy (Group 1) and 16 babies of mothers with tuberculoid leprosy and non-leprosy control mothers (Group 2). IgA anti-M. leprae antibody activity could be detected in 30% and IgM anti-M. leprae antibody activity in 50% of cord sera from Group 1, but not in any of the cord sera from Group 2. After birth, there was a significantly higher increase of IgA and IgM anti-M. leprae antibody activity in sera taken 3-6 months after birth from babies of Group 1 compared to Group 2, but the IgA and IgM activity in sera taken after 6 months of age showed the same increase in the two groups. IgG anti-M. leprae antibody activity showed a marked decrease in sera from both Groups 1 and 2 taken 3-6 and 6-9 months after birth compared to the activity in the cord sera. No increase of the IgG activity could be demonstrated even in sera taken 15-24 months after birth in any of the two groups. These findings are discussed in relation to possible transfer of M. leprae bacilli across the placenta, the influence of M. leprae and other mycobacteria exposure on the antibody activity, the poor IgG anti-M. leprae antibody response and subclinical leprosy infection in babies exposed to leprosy below 2 years of age. PMID:6756719

  19. Losartan and Dexamethasone may inhibit chemotaxis to reduce the infiltration of Th22 cells in IgA nephropathy.

    PubMed

    Xiao, Chenggen; Zhou, Qiaoling; Li, Xiaozhao; Li, Hui; Zhong, Yong; Meng, Ting; Zhu, Mengyuan; Sun, Hong; Liu, Shuang; Tang, Rong; Pu, Jiaxi; Xu, Yan; Xiao, Ping

    2017-01-01

    Angiotensin II is considered a major profibrotic factor that is involved in tissue remodeling processes, as the inhibition of Angiotensin II can halt renal inflammatory processes. Dexamethasone, an important anti-inflammatory and immunosuppressive agent, has been widely used to treat renal disease for decades. In this study, we explored the frequency of Th22 cells in a mouse model of IgA nephropathy and compared the possible effects of Losartan and Dexamethasone on Th22 cells. The experiments were performed using 6-week-old BALB/c female mice in an established IgA nephropathy model. The mice were randomly separated into 4 groups, which were administered Losartan (30mg/kg/d) or Dexamethasone (10mg/kg/d) and subjected to IgA nephropathy or the normal control treatment for 1month. The frequency of Th22 cells was measured via flow cytometry, and the relative pathological changes in renal morphology were measured with different pathological staining methods. Immunohistochemistry was performed to verify the expression of CCR10 and CCL27, which is specialized receptor on Th22 cells and its corresponding chemokine, respectively. The concentrations of CCL27 and IL-22 in renal tissue homogenates and sera were detected using ELISAs. Losartan and Dexamethasone differentially decreased the frequency of Th22 cells after 1month, and mesangial cell proliferation was also improved. Moreover, the expression of CCR10, CCL27 and IL-22 was reduced by treatment with either drug. However, significant differences between Losartan and Dexamethasone were not observed. Based on these findings, Losartan and Dexamethasone may suppress inflammatory responses by inhibiting the chemotaxis of Th22 cells in IgA nephropathy. Copyright © 2016. Published by Elsevier B.V.

  20. IgA Antibodies in Rett Syndrome

    ERIC Educational Resources Information Center

    Reichelt, K. L.; Skjeldal, O.

    2006-01-01

    The level of IgA antibodies to gluten and gliadin proteins found in grains and to casein found in milk, as well as the level of IgG to gluten and gliadin, have been examined in 23 girls with Rett syndrome and 53 controls. Highly statistically significant increases were found for the Rett population compared to the controls. The reason for this…

  1. Lack of serologic evidence to link IgA nephropathy with celiac disease or immune reactivity to gluten.

    PubMed

    Moeller, Sina; Canetta, Pietro A; Taylor, Annette K; Arguelles-Grande, Carolina; Snyder, Holly; Green, Peter H; Kiryluk, Krzysztof; Alaedini, Armin

    2014-01-01

    IgA nephropathy is the most common form of primary glomerulonephritis worldwide. Mucosal infections and food antigens, including wheat gluten, have been proposed as potential contributing environmental factors. Increased immune reactivity to gluten and/or association with celiac disease, an autoimmune disorder triggered by ingestion of gluten, have been reported in IgA nephropathy. However, studies are inconsistent about this association. We aimed to evaluate the proposed link between IgA nephropathy and celiac disease or immune reactivity to gluten by conducting a comprehensive analysis of associated serologic markers in cohorts of well-characterized patients and controls. Study participants included patients with biopsy-proven IgA nephropathy (n = 99), unaffected controls of similar age, gender, and race (n = 96), and patients with biopsy-proven celiac disease (n = 30). All serum specimens were tested for IgG and IgA antibodies to native gliadin and deamidated gliadin, as well as IgA antibody to transglutaminase 2 (TG2). Anti-TG2 antibody-positive nephropathy patients and unaffected controls were subsequently tested for IgA anti-endomysial antibody and genotyped for celiac disease-associated HLA-DQ2 and -DQ8 alleles. In comparison to unaffected controls, there was not a statistically significant increase in IgA or IgG antibody reactivity to gliadin in individuals with IgA nephropathy. In addition, the levels of celiac disease-specific serologic markers, i.e., antibodies to deamidated gliadin and TG2, did not differ between IgA nephropathy patients and unaffected controls. Results of the additional anti-endomysial antibody testing and HLA genotyping were corroborative. The data from this case-control study do not reveal any evidence to suggest a significant role for celiac disease or immune reactivity to gluten in IgA nephropathy.

  2. Lack of Serologic Evidence to Link IgA Nephropathy with Celiac Disease or Immune Reactivity to Gluten

    PubMed Central

    Moeller, Sina; Canetta, Pietro A.; Taylor, Annette K.; Arguelles-Grande, Carolina; Snyder, Holly; Green, Peter H.; Kiryluk, Krzysztof; Alaedini, Armin

    2014-01-01

    IgA nephropathy is the most common form of primary glomerulonephritis worldwide. Mucosal infections and food antigens, including wheat gluten, have been proposed as potential contributing environmental factors. Increased immune reactivity to gluten and/or association with celiac disease, an autoimmune disorder triggered by ingestion of gluten, have been reported in IgA nephropathy. However, studies are inconsistent about this association. We aimed to evaluate the proposed link between IgA nephropathy and celiac disease or immune reactivity to gluten by conducting a comprehensive analysis of associated serologic markers in cohorts of well-characterized patients and controls. Study participants included patients with biopsy-proven IgA nephropathy (n = 99), unaffected controls of similar age, gender, and race (n = 96), and patients with biopsy-proven celiac disease (n = 30). All serum specimens were tested for IgG and IgA antibodies to native gliadin and deamidated gliadin, as well as IgA antibody to transglutaminase 2 (TG2). Anti-TG2 antibody-positive nephropathy patients and unaffected controls were subsequently tested for IgA anti-endomysial antibody and genotyped for celiac disease-associated HLA-DQ2 and -DQ8 alleles. In comparison to unaffected controls, there was not a statistically significant increase in IgA or IgG antibody reactivity to gliadin in individuals with IgA nephropathy. In addition, the levels of celiac disease-specific serologic markers, i.e., antibodies to deamidated gliadin and TG2, did not differ between IgA nephropathy patients and unaffected controls. Results of the additional anti-endomysial antibody testing and HLA genotyping were corroborative. The data from this case-control study do not reveal any evidence to suggest a significant role for celiac disease or immune reactivity to gluten in IgA nephropathy. PMID:24732864

  3. Effects of astaxanthin-enriched yeast on mucosal IgA induction in the jejunum and ileum of weanling mice.

    PubMed

    Nagayama, Tatsuhiko; Sugimoto, Miki; Ikeda, Shuntaro; Kume, Shinichi

    2014-04-01

    The present study was conducted to clarify the effects of astaxanthin-enriched yeast on the concentration of immunoglobulin A (IgA), the numbers of IgA antibody-secreting cells (ASC) and the messenger RNA (mRNA) expression of IgA C-region in the jejunum and ileum of weanling mice. Weanling mice were fed rodent feed or astaxanthin-enriched yeast-supplemented rodent feed for 7, 14 or 21 days. Supplemental astaxanthin-enriched yeast increased the numbers of IgA ASC in the jejunum and ileum after 7, 14 and 21 days of treatment. Supplemental astaxanthin-enriched yeast increased IgA concentrations in the jejunum after 21 days of treatment, but IgA concentrations in the ileum were not affected by the treatment. The mRNA expressions of IgA C-region in the jejunum after 14 and 21 days of treatment and the ileum after 14 days of treatment were enhanced by supplementation of astaxanthin-enriched yeast. These results indicate that supplementation of astaxanthin-enriched yeast is effective to enhance the numbers of IgA ASC in the jejunum and ileum and IgA concentrations in the ileum of weanling mice. © 2013 Japanese Society of Animal Science.

  4. Prominent role for plasmacytoid dendritic cells in mucosal T cell-independent IgA induction.

    PubMed

    Tezuka, Hiroyuki; Abe, Yukiko; Asano, Jumpei; Sato, Taku; Liu, Jiajia; Iwata, Makoto; Ohteki, Toshiaki

    2011-02-25

    Although both conventional dendritic cells (cDCs) and plasmacytoid dendritic cells (pDCs) are present in the gut-associated lymphoid tissues (GALT), the roles of pDCs in the gut remain largely unknown. Here we show a critical role for pDCs in T cell-independent (TI) IgA production by B cells in the GALT. When pDCs of the mesenteric lymph nodes (MLNs) and Peyer's patches (PPs) (which are representative GALT) were cultured with naive B cells to induce TI IgA class switch recombination (CSR), IgA production was substantially higher than in cocultures of these cells with cDCs. IgA production was dependent on APRIL and BAFF production by pDCs. Importantly, pDC expression of APRIL and BAFF was dependent on stromal cell-derived type I IFN signaling under steady-state conditions. Our findings provide insight into the molecular basis of pDC conditioning to induce mucosal TI IgA production, which may lead to improvements in vaccination strategies and treatment for mucosal-related disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Genome expression analyses revealing the modulation of the Salmonella Rcs regulon by the attenuator IgaA.

    PubMed

    Mariscotti, Javier F; García-del Portillo, Francisco

    2009-03-01

    Intracellular growth attenuator A (IgaA) was identified as a Salmonella enterica regulator limiting bacterial growth inside fibroblasts. Genetic evidence further linked IgaA to repression of the RcsCDB regulatory system, which responds to envelope stress. How IgaA attenuates this system is unknown. Here, we present genome expression profiling data of S. enterica serovar Typhimurium igaA mutants grown at high osmolarity and displaying exacerbated Rcs responses. Transcriptome data revealed that IgaA attenuates gene expression changes requiring phosphorylated RcsB (RcsB~P) activity. Some RcsB-regulated genes, yciGFE and STM1862 (pagO)-STM1863-STM1864, were equally expressed in wild-type and igaA strains, suggesting a maximal expression at low levels of RcsB ~P. Other genes, such as metB, ypeC, ygaC, glnK, glnP, napA, glpA, and nirB, were shown for the first time and by independent methods to be regulated by the RcsCDB system. Interestingly, IgaA-deficient strains with reduced RcsC or RcsD levels exhibited different Rcs responses and distinct virulence properties. spv virulence genes were differentially expressed in most of the analyzed strains. spvA expression required RcsB and IgaA but, unexpectedly, was also impaired upon stimulation of the RcsC-->RcsD-->RcsB phosphorelay. Overproduction of either RcsB(+) or a nonphosphorylatable RcsB(D56Q) variant in strains displaying low spvA expression unveiled that both dephosphorylated RcsB and RcsB~P are required for optimal spvA expression. Taken together, our data support a model with IgaA attenuating the RcsCDB system by favoring the switch of RcsB~P to the dephosphorylated state. This role of IgaA in constantly fine-tuning the RcsB~P/RcsB ratio may ensure the proper expression of important virulence factors, such as the Spv proteins.

  6. Host-Primed Ebola Virus GP Exposes a Hydrophobic NPC1 Receptor-Binding Pocket, Revealing a Target for Broadly Neutralizing Antibodies.

    PubMed

    Bornholdt, Zachary A; Ndungo, Esther; Fusco, Marnie L; Bale, Shridhar; Flyak, Andrew I; Crowe, James E; Chandran, Kartik; Saphire, Erica Ollmann

    2016-02-23

    The filovirus surface glycoprotein (GP) mediates viral entry into host cells. Following viral internalization into endosomes, GP is cleaved by host cysteine proteases to expose a receptor-binding site (RBS) that is otherwise hidden from immune surveillance. Here, we present the crystal structure of proteolytically cleaved Ebola virus GP to a resolution of 3.3 Å. We use this structure in conjunction with functional analysis of a large panel of pseudotyped viruses bearing mutant GP proteins to map the Ebola virus GP endosomal RBS at molecular resolution. Our studies indicate that binding of GP to its endosomal receptor Niemann-Pick C1 occurs in two distinct stages: the initial electrostatic interactions are followed by specific interactions with a hydrophobic trough that is exposed on the endosomally cleaved GP1 subunit. Finally, we demonstrate that monoclonal antibodies targeting the filovirus RBS neutralize all known filovirus GPs, making this conserved pocket a promising target for the development of panfilovirus therapeutics. Ebola virus uses its glycoprotein (GP) to enter new host cells. During entry, GP must be cleaved by human enzymes in order for receptor binding to occur. Here, we provide the crystal structure of the cleaved form of Ebola virus GP. We demonstrate that cleavage exposes a site at the top of GP and that this site binds the critical domain C of the receptor, termed Niemann-Pick C1 (NPC1). We perform mutagenesis to find parts of the site essential for binding NPC1 and map distinct roles for an upper, charged crest and lower, hydrophobic trough in cleaved GP. We find that this 3-dimensional site is conserved across the filovirus family and that antibody directed against this site is able to bind cleaved GP from every filovirus tested and neutralize viruses bearing those GPs. Copyright © 2016 Bornholdt et al.

  7. Dysregulated LIGHT expression on T cells mediates intestinal inflammation and contributes to IgA nephropathy

    PubMed Central

    Wang, Jing; Anders, Robert A.; Wu, Qiang; Peng, Dacheng; Cho, Judy H.; Sun, Yonglian; Karaliukas, Reda; Kang, Hyung-Sik; Turner, Jerrold R.; Fu, Yang-Xin

    2004-01-01

    Whether and how T cells contribute to the pathogenesis of immunoglobulin A nephropathy (IgAN) has not been well defined. Here, we explore a murine model that spontaneously develops T cell–mediated intestinal inflammation accompanied by pathological features similar to those of human IgAN. Intestinal inflammation mediated by LIGHT, a ligand for lymphotoxin β receptor (LTβR), not only stimulates IgA overproduction in the gut but also results in defective IgA transportation into the gut lumen, causing a dramatic increase in serum polymeric IgA. Engagement of LTβR by LIGHT is essential for both intestinal inflammation and hyperserum IgA syndrome in our LIGHT transgenic model. Impressively, the majority of patients with inflammatory bowel disease showed increased IgA-producing cells in the gut, elevated serum IgA levels, and severe hematuria, a hallmark of IgAN. These observations indicate the critical contributions of dysregulated LIGHT expression and intestinal inflammation to the pathogenesis of IgAN. PMID:15067315

  8. Detection of H. Pylori infection on dyspepsia patients with IgA H. Pylori antibody

    NASA Astrophysics Data System (ADS)

    Loesnihari, R.

    2018-03-01

    Helicobacter pylori (H. pylori) has a big role in the relapse and pathogenesis of the upper gastrointestinal disease. Dyspepsia is characterized by uncomfortable feeling at the upper gastrointestinal area. IgA H. pylori antibody was in two-thirds of H. pylori infected patients, but about 7.2% of IgA H. Pylori antibody became the only positive result of the test between the two serology test (IgG and IgA). A cross-sectional study was conducted in 38 patients with dyspepsia. The IgA antibody test for H. pylori in the serum of dyspepsia patient conducted through the ELISA test. The hemoglobin levels, leukocytes, platelets number, and H. pylori infection via IgA antibody test on ulcer and non-ulcer dyspepsia patient had no significant difference. There was a relation between the number of platelets in the infected H. pylori patients compared to the non-infected patients. H. pylori infection in the ulcer and non-ulcer dyspepsia patient with serology method was 18%. H. pylori infection number on ulcer dyspepsia was not higher than the non-ulcer dyspepsia, all ulcer dyspepsia patients who were with H. pylori found with a lesion on the antrum.

  9. Neuronal nitric oxide synthase mediates the effect of ethanol on IgA.

    PubMed

    Budec, Mirela; Markovic, Dragana; Vignjevic, Sanja; Mitrovic, Olivera; Dikic, Dragoslava; Koko, Vesna; Cokic, Vladan P

    2013-01-01

    We showed previously that the acute effect of ethanol on intestinal immunoglobulin A (IgA) expression might be mediated by endogenous nitric oxide (NO). To extend these findings, this study was designed to investigate a possible role of neuronal NO synthase (nNOS) in the observed phenomenon, using 7-nitroindazole (7-NI), a selective inhibitor of its activity. Adult male Wistar rats were treated with: (a) ethanol (4 g/kg, intraperitoneally, i.p.), (b) 7-NI (25 mg/kg, i.p.) followed by ethanol (4 g/kg, i.p.) 30 min later and (c) 7-NI (25 mg/kg, i.p.) followed by saline 30 min later. Untreated rats were used as controls. The concentrations of serum and intestinal IgA were measured by enzyme-linked immunosorbent assay, while the expression of nNOS was determined using western blot and immunohistochemistry. Acute ethanol treatment significantly increased the concentration of IgA in the ileal extracts, whereas it decreased its serum level. Inhibition of nNOS activity by 7-NI abolished this action of alcohol on IgA. Additionally, western blot analysis revealed that the acute alcohol administration induced an increase in the expression of intestinal nNOS. Furthermore, nNOS-immunoreactive cells, observed within the lamina propria of small intestine, were numerous in ethanol-treated rats. Taken together, these results extended our previous findings suggesting that nNOS mediates the acute effect of ethanol on IgA and supported an immunomodulatory role of this enzyme isoform.

  10. Interaction between the macrophage system and IgA immune complexes in IgA nephropathy.

    PubMed

    Roccatello, D; Coppo, R; Basolo, B; Martina, G; Rollino, C; Cordonnier, D; Busquet, G; Picciotto, G; Sena, L M; Piccoli, G

    1983-01-01

    In nine patients with IgA nephropathy, the function of the mononuclear phagocyte system was assessed by measuring in vivo clearance of anti-D coated red blood cells (RBC) and in vitro phagocytosis of sensitised RBC by monocytes. A strict correlation was found between in vivo macrophage function and in vitro monocyte phagocytosis. Statistical correlations were also found between in vivo clearance values and IgAIC and C3d values. A defective macrophage and monocyte function affects patients with major signs of clinical activity, highest IgAIC values, signs of complement activation and the most unfavourable clinical course.

  11. Large Scale Generation and Characterization of Anti-Human IgA Monoclonal Antibody in Ascitic Fluid of Balb/c Mice

    PubMed Central

    Ezzatifar, Fatemeh; Majidi, Jafar; Baradaran, Behzad; Aghebati Maleki, Leili; Abdolalizadeh, Jalal; Yousefi, Mehdi

    2015-01-01

    Purpose: Monoclonal antibodies are potentially powerful tools used in biomedical research, diagnosis, and treatment of infectious diseases and cancers. The monoclonal antibody against Human IgA can be used as a diagnostic application to detect infectious diseases. The aim of this study was to improve an appropriate protocol for large-scale production of mAbs against IgA. Methods: For large-scale production of the monoclonal antibody, hybridoma cells that produce monoclonal antibodies against Human IgA were injected intraperitoneally into Balb/c mice that were previously primed with 0.5 ml Pristane. After ten days, ascitic fluid was harvested from the peritoneum of each mouse. The ELISA method was carried out for evaluation of the titration of produced mAbs. The ascitic fluid was investigated in terms of class and subclass by a mouse mAb isotyping kit. MAb was purified from the ascitic fluid by ion exchange chromatography. The purity of the monoclonal antibody was confirmed by SDS-PAGE, and the purified monoclonal antibody was conjugated with HRP. Results: Monoclonal antibodies with high specificity and sensitivity against Human IgA were prepared by hybridoma technology. The subclass of antibody was IgG1 and its light chain was the kappa type. Conclusion: This conjugated monoclonal antibody could have applications in designing ELISA kits in order to diagnose different infectious diseases such as toxoplasmosis and H. Pylori. PMID:25789225

  12. Lambda light chain revision in the human intestinal IgA response.

    PubMed

    Su, Wen; Gordon, John N; Barone, Francesca; Boursier, Laurent; Turnbull, Wayne; Mendis, Surangi; Dunn-Walters, Deborah K; Spencer, Jo

    2008-07-15

    Revision of Ab L chains by secondary rearrangement in mature B cells has the potential to change the specific target of the immune response. In this study, we show for the first time that L chain revision is normal and widespread in the largest Ab producing population in man: intestinal IgA plasma cells (PC). Biases in the productive and non-productive repertoire of lambda L chains, identification of the circular products of rearrangement that have the characteristic biases of revision, and identification of RAG genes and protein all reflect revision during normal intestinal IgA PC development. We saw no evidence of IgH revision, probably due to inappropriately orientated recombination signal sequences, and little evidence of kappa-chain revision, probably due to locus inactivation by the kappa-deleting element. We propose that the lambda L chain locus is available and a principal modifier and diversifier of Ab specificity in intestinal IgA PCs.

  13. Purified Hexameric Epstein-Barr Virus-Encoded BARF1 Protein for Measuring Anti-BARF1 Antibody Responses in Nasopharyngeal Carcinoma Patients▿

    PubMed Central

    Hoebe, E. K.; Hutajulu, S. H.; van Beek, J.; Stevens, S. J.; Paramita, D. K.; Greijer, A. E.; Middeldorp, J. M.

    2011-01-01

    WHO type III nasopharyngeal carcinoma (NPC) is highly prevalent in Indonesia and 100% associated with Epstein-Barr virus (EBV). NPC tumor cells express viral proteins, including BARF1, which is secreted and is considered to have oncogenic and immune-modulating properties. Recently, we found conserved mutations in the BARF1 gene in NPC isolates. This study describes the expression and purification of NPC-derived BARF1 and analyzes humoral immune responses against prototype BARF1 (B95-8) and purified native hexameric BARF1 in sera of Indonesian NPC patients (n = 155) compared to healthy EBV-positive (n = 56) and EBV-negative (n = 16) individuals. BARF1 (B95-8) expressed in Escherichia coli and baculovirus, as well as BARF1-derived peptides, did not react with IgG or IgA antibodies in NPC. Purified native hexameric BARF1 protein isolated from culture medium was used in enzyme-linked immunosorbent assay (ELISA) and revealed relatively weak IgG and IgA responses in human sera, although it had strong antibody responses to other EBV proteins. Higher IgG reactivity was found in NPC patients (P = 0.015) than in regional Indonesian controls or EBV-negative individuals (P < 0.001). IgA responses to native BARF1 were marginal. NPC sera with the highest IgG responses to hexameric BARF1 in ELISA showed detectable reactivity with denatured BARF1 by immunoblotting. In conclusion, BARF1 has low immunogenicity for humoral responses and requires native conformation for antibody binding. The presence of antibodies against native BARF1 in the blood of NPC patients provides evidence that the protein is expressed and secreted as a hexameric protein in NPC patients. PMID:21123521

  14. IgA is Important for Clearance and Critical for Protection from Rotavirus Infection

    PubMed Central

    Blutt, Sarah E; Miller, Amber D.; Salmon, Sharon L.; Metzger, Dennis W.; Conner, Margaret E

    2012-01-01

    Based on a lack of severe phenotype in human IgA deficiency syndromes, the role of IgA in controlling respiratory and gastrointestinal (GI) infections has not been clearly defined. C57BL/6 and BALB/c mice lacking IgA (IgA−/−) were developed and used to address this question. When exposed to a common GI virus, rotavirus, IgA−/− mice exhibited a substantial and significant delay in clearance of the initial infection compared to wild type mice. IgA−/− mice excreted rotavirus in stool up to three weeks after the initial exposure compared to ten days observed in wild type mice. Importantly, IgA−/− mice failed to develop protective immunity against multiple repeat exposures to the virus. All IgA−/− mice excreted virus in the stool upon re-exposure to rotavirus while wild type mice were completely protected against re-infection. These findings clearly indicate a critical role for IgA in the establishment of immunity against a GI viral pathogen. PMID:22739233

  15. Eosinophils may play regionally disparate roles in influencing IgA(+) plasma cell numbers during large and small intestinal inflammation.

    PubMed

    Forman, Ruth; Bramhall, Michael; Logunova, Larisa; Svensson-Frej, Marcus; Cruickshank, Sheena M; Else, Kathryn J

    2016-05-31

    Eosinophils are innate immune cells present in the intestine during steady state conditions. An intestinal eosinophilia is a hallmark of many infections and an accumulation of eosinophils is also observed in the intestine during inflammatory disorders. Classically the function of eosinophils has been associated with tissue destruction, due to the release of cytotoxic granule contents. However, recent evidence has demonstrated that the eosinophil plays a more diverse role in the immune system than previously acknowledged, including shaping adaptive immune responses and providing plasma cell survival factors during the steady state. Importantly, it is known that there are regional differences in the underlying immunology of the small and large intestine, but whether there are differences in context of the intestinal eosinophil in the steady state or inflammation is not known. Our data demonstrates that there are fewer IgA(+) plasma cells in the small intestine of eosinophil-deficient ΔdblGATA-1 mice compared to eosinophil-sufficient wild-type mice, with the difference becoming significant post-infection with Toxoplasma gondii. Remarkably, and in complete contrast, the absence of eosinophils in the inflamed large intestine does not impact on IgA(+) cell numbers during steady state, and is associated with a significant increase in IgA(+) cells post-infection with Trichuris muris compared to wild-type mice. Thus, the intestinal eosinophil appears to be less important in sustaining the IgA(+) cell pool in the large intestine compared to the small intestine, and in fact, our data suggests eosinophils play an inhibitory role. The dichotomy in the influence of the eosinophil over small and large intestinal IgA(+) cells did not depend on differences in plasma cell growth factors, recruitment potential or proliferation within the different regions of the gastrointestinal tract (GIT). We demonstrate for the first time that there are regional differences in the requirement of

  16. Prevaccination Rotavirus Serum IgG and IgA Are Associated With Lower Immunogenicity of Live, Oral Human Rotavirus Vaccine in South African Infants.

    PubMed

    Moon, Sung-Sil; Groome, Michelle J; Velasquez, Daniel E; Parashar, Umesh D; Jones, Stephanie; Koen, Antoinette; van Niekerk, Nadia; Jiang, Baoming; Madhi, Shabir A

    2016-01-15

    Live oral rotavirus (RV) vaccines have shown modest efficacy among children in African countries for reasons that are not completely understood. We examined the possible inhibitory effect of preexisting antirotavirus antibodies on immunogenicity of monovalent RV vaccine (RV1). Mother-infant pairs were enrolled at presentation for their routine immunization visit in Soweto, South Africa, when infants were aged 5-8 weeks. Infant serum samples were obtained before the first and second doses of RV1 and 1 month after the second dose. Maternal serum and breast milk samples were obtained prior to administration of each dose of RV1 to infants. RV-specific immunoglobulin G (IgG), IgA, and neutralizing activity in sera of infants and serum or breast milk samples of mothers were measured using enzyme-linked immunosorbent assays or a microneutralization test. Of the 107 serum pairs from infants who were seronegative for RV IgA at enrollment, we observed a strong positive association between IgG titers in pre-dose 1 sera of infants and mothers and significant negative associations between IgG titers in pre-dose 1 sera of infants and seroconversion to RV1 post-dose 1. Similarly, mothers whose infants' IgA seroconverted after RV1 had significantly lower pre-dose 1 IgG titers in sera than those whose infants did not seroconvert. High levels of preexisting serum IgG, including transplacentally acquired maternal IgG, appeared to have an inhibitory effect on the immunogenicity of RV1 among infants and may, in part, contribute to lower efficacy of RV vaccines in this and other low-income settings. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  17. The mismatch repair and meiotic recombination endonuclease Mlh1-Mlh3 is activated by polymer formation and can cleave DNA substrates in trans.

    PubMed

    Manhart, Carol M; Ni, Xiaodan; White, Martin A; Ortega, Joaquin; Surtees, Jennifer A; Alani, Eric

    2017-04-01

    Crossing over between homologs is initiated in meiotic prophase by the formation of DNA double-strand breaks that occur throughout the genome. In the major interference-responsive crossover pathway in baker's yeast, these breaks are resected to form 3' single-strand tails that participate in a homology search, ultimately forming double Holliday junctions (dHJs) that primarily include both homologs. These dHJs are resolved by endonuclease activity to form exclusively crossovers, which are critical for proper homolog segregation in Meiosis I. Recent genetic, biochemical, and molecular studies in yeast are consistent with the hypothesis of Mlh1-Mlh3 DNA mismatch repair complex acting as the major endonuclease activity that resolves dHJs into crossovers. However, the mechanism by which the Mlh1-Mlh3 endonuclease is activated is unknown. Here, we provide evidence that Mlh1-Mlh3 does not behave like a structure-specific endonuclease but forms polymers required to generate nicks in DNA. This conclusion is supported by DNA binding studies performed with different-sized substrates that contain or lack polymerization barriers and endonuclease assays performed with varying ratios of endonuclease-deficient and endonuclease-proficient Mlh1-Mlh3. In addition, Mlh1-Mlh3 can generate religatable double-strand breaks and form an active nucleoprotein complex that can nick DNA substrates in trans. Together these observations argue that Mlh1-Mlh3 may not act like a canonical, RuvC-like Holliday junction resolvase and support a novel model in which Mlh1-Mlh3 is loaded onto DNA to form an activated polymer that cleaves DNA.

  18. High salivary secretory IgA antibody levels are associated with less late-onset wheezing in IgE-sensitized infants.

    PubMed

    Sandin, Anna; Björkstén, Bengt; Böttcher, Malin F; Englund, Erling; Jenmalm, Maria C; Bråbäck, Lennart

    2011-08-01

    Low levels of secretory IgA (SIgA) and transient IgA deficiency have been associated with an increased risk for allergy, but data are conflicting. The aim was to assess the relationship between salivary SIgA antibody levels at 1 yr and wheezing at age four in a birth cohort, in particular the possible protective role of salivary SIgA in sensitized children. Saliva samples were obtained from all children (n=67) with a positive skin prick test (SPT) at 1 yr and 212 children with a negative SPT. In all, 200 of these children responded to questionnaires at 4 yrs and 183 were skin prick tested at that age. The levels of salivary SIgA and salivary IgA antibodies to the most common food allergen egg and inhalant allergen cat were analyzed by ELISA. Serum was analyzed for IgE antibodies to egg and cat. Development of late-onset wheezing was associated with low SIgA levels in children with positive SPT to at least one allergen both at 1 and 4 yrs of age (p=0.04), as well as in children with circulating IgE antibodies to egg or cat at 1 yr (p=0.02). None of nine persistently sensitized children with SIgA levels in the upper quartile developed wheezing, when compared to 10/20 children with lower levels (p=0.01). Older siblings, more than three infections during infancy, at least one smoking parent, and male gender, were all associated with SIgA in the upper quartile. In conclusion, high levels of SIgA antibodies in sensitized infants were associated with significantly less late-onset wheezing, supporting a protective role against development of asthmatic symptoms. Recurrent infections and other factors supporting an increased microbial pressure during infancy were associated with high levels of salivary SIgA. © 2011 John Wiley & Sons A/S.

  19. A LGG-derived protein promotes IgA production through up-regulation of APRIL expression in intestinal epithelial cells

    PubMed Central

    Wang, Yang; Liu, Liping; Moore, Daniel J; Shen, Xi; Peek, Richard M.; Acra, Sari A; Li, Hui; Ren, Xiubao; Polk, D Brent; Yan, Fang

    2016-01-01

    p40, a Lactobacillus rhamnosus GG (LGG)-derived protein, transactivates epidermal growth factor receptor (EGFR) in intestinal epithelial cells, leading to amelioration of intestinal injury and inflammation. To elucidate mechanisms by which p40 regulates mucosal immunity to prevent inflammation, this study aimed to determine the effects and mechanisms of p40 on regulation of a proliferation-inducing ligand (APRIL) expression in intestinal epithelial cells for promoting IgA production. p40 up-regulated April gene expression and protein production in mouse small intestine epithelial (MSIE) cells, which were inhibited by blocking EGFR expression and kinase activity. Enteroids from Egfrfl/fl , but not Egfrfl/fl-Vil-Cre mice with EGFR specifically deleted in intestinal epithelial cells, exhibited increased April gene expression by p40 treatment. p40-conditioned media from MSIE cells increased B cell class switching to IgA+ cells and IgA production, which was suppressed by APRIL receptor neutralizing antibodies. Treatment of B cells with p40 did not show any effects on IgA production. p40 treatment increased April gene expression and protein production in small intestinal epithelial cells, fecal IgA levels, IgA+B220+, IgA+CD19+, and IgA+ plasma cells in lamina propria of Egfrfl/fl, but not Egfrfl/fl-Vil-Cre mice. Thus, p40 up-regulates EGFR-dependent APRIL production in intestinal epithelial cells, which may contribute to promoting IgA production. PMID:27353252

  20. Membrane type 1-matrix metalloproteinase cleaves off the NH2-terminal portion of heparin-binding epidermal growth factor and converts it into a heparin-independent growth factor.

    PubMed

    Koshikawa, Naohiko; Mizushima, Hiroto; Minegishi, Tomoko; Iwamoto, Ryo; Mekada, Eisuke; Seiki, Motoharu

    2010-07-15

    Epidermal growth factor (EGF) receptors (ErbB) and EGF family members represent promising targets for cancer therapy. Heparin-binding EGF (HB-EGF) is a member of the EGF family and is an important target for therapy in some types of human cancers. Processing of HB-EGF by proprotein convertases, and successively, by ADAM family proteases, generates a soluble growth factor that requires heparin as a cofactor. Although heparin potentiates HB-EGF activity in vitro, it is not clear how the heparin-binding activity of HB-EGF is regulated. Here, we show that membrane type 1-matrix metalloproteinase (MT1-MMP; MMP14), a potent invasion-promoting protease, markedly enhances HB-EGF-dependent tumor formation in mice. MT1-MMP additionally cleaves HB-EGF and removes the NH(2)-terminal 20 amino acids that are important for binding heparin. Consequently, the processing of HB-EGF by MT1-MMP converts HB-EGF into a heparin-independent growth factor with enhanced mitogenic activity, and thereby, expression of both proteins costimulates tumor cell growth in vitro and in vivo. The ErbB family of receptors expressed in human gastric carcinoma cells play a role in mediating enhanced HB-EGF activity by MT1-MMP during invasive cell growth in collagen. Thus, we shed light on a new mechanism whereby HB-EGF activity is regulated that should be considered when designing HB-EGF-targeted cancer therapy. (c)2010 AACR.

  1. Chronic myeloid leukemia in a child with IgA nephropathy.

    PubMed

    Udani, Amish; Vijayakumar, Mahalingam; Prahlad, Nageswaran; Ekambaram, Sudha

    2012-08-01

    We report an 11 year old boy with IgA nephropathy developing chronic myeloid leukemia on follow-up. This association suggests that a B cell defect might be involved in the pathogenesis of these two conditions.

  2. Salivary IgA and dental caries in HIV patients: A pilot study.

    PubMed

    Acharya, Sonu; Mandal, Pradip Kumar

    2016-01-01

    The interrelationship of human immunodeficiency virus (HIV) infection and dental caries, as well as Salivary IgA (S-IgA) level, appear to remain underexplored while a manual and electronic search of the literature was made. Hence, this study was undertaken to assess the relationship of S-IgA and dental caries status in HIV +ve children. The aim of this study was to find out the relationship of S-IgA antibody with dental caries by measuring the concentration of IgA in saliva of HIV +ve and HIV -ve children and to determine the dental caries status in HIV +ve and HIV -ve children, which may help in treatment planning and prevention of the same. Twenty-eight HIV +ve children aged between 6 and 14 years and 28 age matched HIV -ve children were included in this study, and both samples were randomly selected from the same nongovernmental organization (NGO). The HIV status of both these samples was confirmed from their medical records provided by the NGO. 2 cc of unstimulated saliva was collected from both groups in special tubes coded numerically using the method described by Collins and Dawes, and the samples were analyzed to measure the concentration of IgA using commercially available ELISA kit (DRG Diagnostics, Germany). Examination of dental caries was carried out according to the WHO criteria (1997) using a flat mouth mirror and Community periodontal index (CPI) probe. In HIV +ve group, mean salivary IgA level was calculated as 81.61 ± 6.20 μg/ml, mean decayed, missing, filled teeth (DMFT) was 3.86 ± 3.37, mean decayed, extracted and filled teeth (deft) was 4.75 ± 2.86. In HIV -ve group, the mean salivary IgA level was calculated as 145.57 ±17.83 μg/ml, mean DMFT was 2.54 ± 0.69, mean deft was 2.43 ± 2.01. Strong -ve correlation between S-IgA and DMFT (r = -0.781, t = 6.38, P < 0.001) and negative, but not significant correlation (r = -0.19, t = 0.99, P > 0.05) between S-IgA and deft was found in HIV +ve group. Strong -ve correlation between S-IgA and DMFT

  3. Cleaved-edge-overgrowth nanogap electrodes.

    PubMed

    Luber, Sebastian M; Bichler, Max; Abstreiter, Gerhard; Tornow, Marc

    2011-02-11

    We present a method to fabricate multiple metal nanogap electrodes of tailored width and distance in parallel, on the cleaved plane of a GaAs/AlGaAs heterostructure. The three-dimensional patterned structures are obtained by a combination of molecular-beam-epitaxial regrowth on a crystal facet, using the cleaved-edge-overgrowth (CEO) method, and subsequent wet selective etching and metallization steps. SEM and AFM studies reveal smooth and co-planar electrodes of width and distance of the order of 10 nm. Preliminary electrical characterization indicates electrical gap insulation in the 100 MΩ range with kΩ lead resistance. We propose our methodology to realize multiple electrode geometries that would allow investigation of the electrical conductivity of complex nanoscale objects such as branched organic molecules.

  4. The gut-kidney axis in IgA nephropathy: role of microbiota and diet on genetic predisposition.

    PubMed

    Coppo, Rosanna

    2018-01-01

    Recent data suggest that gut-associated lymphoid tissue (GALT) plays a major role in the development of immunoglobulin A (IgA) nephropathy (IgAN). A genome-wide association study showed that most loci associated with the risk of IgAN are also associated with immune-mediated inflammatory bowel diseases, maintenance of the intestinal barrier and regulation of response to gut pathogens. Studies involving experimental models have demonstrated a pivotal role of intestinal microbiota in the development of IgAN in mice producing high levels of IgA and in transgenic mice overexpressing BAFF, a B-cell factor crucial for IgA synthesis, indicating the role of genetic background, B-cell activity, GALT intestinal immunity and diet. The effect of diet was suggested by pilot studies carried out 30 years ago which showed that a gluten-rich diet induced IgAN in mice and that some patients benefited from a gluten-free diet. A recent experimental model in mice expressing human IgA1 and Fc alpha receptor CD89 reported clinical and histological improvement after a gluten-free diet. Clinical observations have elicited new interest in GALT hyper-reactivity in IgAN patients. In a pilot study, a reduction in proteinuria was attained using an enteric controlled-release formulation of the corticosteroid budesonide targeted to the Peyer's patches at the ileocecal junction. This formulation was tested in the placebo-controlled NEFIGAN phase 2b trial, with a reduction in proteinuria after 9 months of treatment together with stabilization of renal function in patients with persistent proteinuria. In conclusion, the gut-kidney axis modulated by microbiota and diet is a promising target for focused treatment of IgAN in genetically predisposed patients at risk of progression.

  5. Development of an ELISA for sensitive and specific detection of IgA autoantibodies against BP180 in pemphigoid diseases

    PubMed Central

    2011-01-01

    Background Pemphigoids are rare diseases associated with IgG, IgE and IgA autoantibodies against collagen XVII/BP180. An entity of the pemphigoid group is the lamina lucida-type of linear IgA disease (IgA pemphigoid) characterized by IgA autoantibodies against BP180. While for the detection of IgG and IgE autoantibodies specific to collagen XVII several ELISA systems have been established, no quantitative immunoassay has been yet developed for IgA autoantibodies. Therefore, the aim of the present study was to develop an ELISA to detect IgA autoantibodies against collagen XVII in the sera of patients with pemphigoids. Methods We expressed a soluble recombinant form of the collagen XVII ectodomain in mammalian cells. Reactivity of IgA autoantibodies from patients with IgA pemphigoid was assessed by immunofluorescence microscopy and immunoblot analysis. ELISA test conditions were determined by chessboard titration experiments. The sensitivity, specificity and the cut-off were determined by receiver-operating characteristics analysis. Results The optimized assay was carried out using sera from patients with IgA pemphigoid (n = 30) and healthy donors (n = 105). By receiver operating characteristics (ROC) analysis, an area under the curve of 0.993 was calculated, indicating an excellent discriminatory capacity. Thus, a sensitivity and specificity of 83.3% and 100%, respectively, was determined for a cut-off point of 0.48. As additional control groups, sera from patients with bullous pemphigoid (n = 31) and dermatitis herpetiformis (n = 50), a disease associated with IgA autoantibodies against epidermal transglutaminase, were tested. In 26% of bullous pemphigoid patients, IgA autoantibodies recognized the ectodomain of collagen XVII. One of 50 (2%) of dermatitis herpetiformis patients sera slightly topped the cut-off value. Conclusions We developed the first ELISA for the specific and sensitive detection of serum IgA autoantibodies specific to collagen XVII in patients

  6. Quantitation of sperm bindable IgA and IgG in seminal fluid.

    PubMed

    Howe, S E; Lynch, D M

    1986-05-01

    Seminal fluid and serum from 95 infertile males were assayed for sperm bindable immunoglobulins using an indirect ELISA with whole target sperm. The ELISA method was compared to seminal fluid and serum immobilization and agglutination assays (functional assays). In this infertile group, the ELISA assay was positive in 22% of seminal fluids (greater than 1.2 fg IgA/sperm and greater than 0.3 fg IgG/sperm). The seminal fluid antibodies were IgA and had an accompanying elevated IgG component in 78% of patients. There was a 96% correlation between negative seminal fluid functional assays and negative ELISA, and a 95% correlation between positive seminal fluid functional assays and positive ELISA. Positive serum sperm antibody tests were found in 71% of the infertile males with positive seminal fluid sperm antibodies, but 29% of the infertile males with strongly positive IgA seminal fluid sperm antibodies showed normal levels of serum sperm antibodies by either ELISA or functional assays. The ELISA method gives reproducible quantitation of sperm antibodies in seminal fluid and correlates well with accepted functional assays. Comparisons with serum sperm antibody assays suggests that seminal fluid sperm antibody analysis complements the serum analysis of sperm antibodies.

  7. Raised serum IgG and IgA antibodies to mycobacterial antigens in rheumatoid arthritis.

    PubMed Central

    Tsoulfa, G; Rook, G A; Van-Embden, J D; Young, D B; Mehlert, A; Isenberg, D A; Hay, F C; Lydyard, P M

    1989-01-01

    Autoantigens cross reactive with mycobacteria are implicated in the pathogenesis of adjuvant arthritis in the rat, and there are reports of changes in the immune response to mycobacteria in human rheumatoid arthritis (RA). We have therefore examined the IgM, IgG, and IgA antibody levels to crude mycobacterial antigens and to two recombinant mycobacterial heat shock/stress proteins (65 kD and 71 kD) in sera from patients with RA, systemic lupus erythematosus (SLE), and Crohn's disease, and from healthy controls. IgA binding to the crude mycobacterial antigens was significantly raised in RA sera, though IgG and IgM binding tended to be lower than in controls. Both IgA and IgG binding to the heat shock proteins were significantly raised in the RA sera. Smaller significant rises in both classes were seen in sera from patients with SLE, and in the IgA class only to the 65 kD protein in Crohn's disease. The rises in IgG and IgA antibodies to the 65 kD protein in RA were significantly higher than in the other diseases, however. It is interesting that this protein is the one responsible for adjuvant arthritis in the rat. PMID:2930263

  8. Enzyme-linked immunosorbent assay for IgA antibodies to Trypanosoma cruzi in congenital infection.

    PubMed

    Di Pentima, M C; Edwards, M S

    1999-02-01

    With the aim of achieving earlier diagnosis of congenital Trypanosoma cruzi infection, we assessed the usefulness of detecting specific IgA antibody by an ELISA. We evaluated 12 pregnant women chronically infected with T. cruzi, their newborn infants, and three additional neonates with parasitemia at birth. The IgA-specific antibody was detected by adapting the procedure for use of a commercial IgG ELISA, the Hemagen Chagas' Kit (Hemagen Diagnostics, Inc., Waltham, MA). Trypanosoma cruzi-specific IgA was detected in 10 (83%) of 12 mothers at delivery, in one of three parasitemic infants, and one of 12 newborns of the chronically infected women. Testing of 13 infants at six months of age revealed IgA in seven infants (54%), of whom four also had persistent T. cruzi-specific IgG. Detection of T. cruzi-specific IgA could provide a criterion for diagnosis of congenital infection in the absence of detectable parasitemia.

  9. The Oxygenase CAO-1 of Neurospora crassa Is a Resveratrol Cleavage Enzyme

    PubMed Central

    Díaz-Sánchez, Violeta; F. Estrada, Alejandro; Limón, M. Carmen; Al-Babili, Salim

    2013-01-01

    The genome of the ascomycete Neurospora crassa encodes CAO-1 and CAO-2, two members of the carotenoid cleavage oxygenase family that target double bonds in different substrates. Previous studies demonstrated the role of CAO-2 in cleaving the C40 carotene torulene, a key step in the synthesis of the C35 apocarotenoid pigment neurosporaxanthin. In this work, we investigated the activity of CAO-1, assuming that it may provide retinal, the chromophore of the NOP-1 rhodopsin, by cleaving β-carotene. For this purpose, we tested CAO-1 activity with carotenoid substrates that were, however, not converted. In contrast and consistent with its sequence similarity to family members that act on stilbenes, CAO-1 cleaved the interphenyl Cα-Cβ double bond of resveratrol and its derivative piceatannol. CAO-1 did not convert five other similar stilbenes, indicating a requirement for a minimal number of unmodified hydroxyl groups in the stilbene background. Confirming its biological function in converting stilbenes, adding resveratrol led to a pronounced increase in cao-1 mRNA levels, while light, a key regulator of carotenoid metabolism, did not alter them. Targeted Δcao-1 mutants were not impaired by the presence of resveratrol, a phytoalexin active against different fungi, which did not significantly affect the growth and development of wild-type Neurospora. However, under partial sorbose toxicity, the Δcao-1 colonies exhibited faster radial growth than control strains in the presence of resveratrol, suggesting a moderate toxic effect of resveratrol cleavage products. PMID:23893079

  10. Potential role for IL-5 and IL-6 in enhanced IgA secretion by Peyer's patch cells isolated from mice acutely exposed to vomitoxin.

    PubMed

    Yan, D; Zhou, H R; Brooks, K H; Pestka, J J

    1997-09-26

    Dietary exposure to vomitoxin (VT) results in hyperelevated serum IgA and IgA nephropathy in mice. To assess the possible role of cytokines in this IgA dysregulation, the effects of a single oral exposure in B6C3F1 male mice to 0, 5 or 25 mg/kg BW VT on production of IgA and cytokines in Peyer's patch (PP) and spleen cell cultures were evaluated. IgA levels were increased significantly in PP cell cultures prepared from mice at 2 or 24 h after oral exposure to VT and subsequently stimulated with phorbol myristate acetate (PMA) and ionomycin (ION) or with lipopolysaccharide (LPS). Significant effects on IgA production were not observed in spleen cell cultures. Since cytokines such as IL-2, IL-4, IL-5 and IL-6 have been shown to promote IgA production, the effect of the same VT exposure regimen on secretion of these mediators was determined in PP and spleen cultures. Supernatant IL-2 and IL-4 levels were unaffected by the prior treatment of animals with VT. In contrast, IL-5 levels were increased significantly in 7-day PP cell cultures obtained 2 h after VT exposure both with and without PMA + ION exposure but not in other cultures. IL-6 levels were increased significantly in LPS-treated cultures prepared from PP at 2 and 24 h following exposure to VT. IL-6 levels were also elevated significantly in both PMA + ION or LPS treated cultures from spleen isolated at 2 h but not 24 h post VT exposure. To determine whether IL-5 or IL-6 play a role in IgA hyperelevation in vitro, PP and spleen cells from mice obtained 2 h after exposure to 25 mg/kg VT were cultured in the presence of neutralizing cytokine antibodies (Abs) and IgA production was monitored. Consistent with IL-5's previously documented role in IgA production, anti-IL-5 decreased IgA levels to background in cultures of both control and VT-exposed PP or spleen cells in the presence of either PMA + ION or LPS. Similar results were seen with addition of anti-IL-6. IgA levels were decreased to a lesser extent in PP

  11. Effect of Anger Patterns and Depression on Serum IgA and NK Cell Frequency.

    PubMed

    Farnam, Alireza; Majidi, Jafar; Nourazar, Seyyed Gholamreza; Ghojazadeh, Morteza; Movassaghpour, Aliakbar; Zolbanin, Saeedeh Majidi

    2016-03-01

    There are conflicting findings about relationship between depression and anger with immunological parameters. To investigate the relationship between anger patterns and immune system in depressed patients. Thirty-five patients with major depressive disorder were selected according to DSM-IV criteria. The Hamilton Depression Scale and Spielberger Anger questionnaires were used to determine severity of depression and "anger expression pattern", respectively. The control group without a previous history of mental illness was also selected. In the group of patients with moderate depression, serum IgA levels and NK cell percentage were measured. Mean differences of all types of "anger expression pattern", including; "state-trait anger", "anger expression out", "anger expression in", "anger control out" and "anger control in", between study and control groups, were statistically significant (p<0.05). Difference in mean serum levels of IgA in either group was not significant (p=0.9), but the mean difference was significant in terms of NK-cell percentage in both groups (p=0.04). There was no significant relationship between IgA levels and percentage of NK- cell with all types of "anger expression pattern" in both groups. Only in the control group, IgA had significant correlation with anger control out (p=0.04). Moderately depressed patients versus control group had higher Spielberger scores in all types of anger expression pattern except anger control-out and anger control-in. We found no evidence supporting the relationship between" anger expression pattern" and IgA levels and NK cell percentage; however, it seems that depression itself causes reduced number of NK cells and increased IgA levels.

  12. Intestinal alkaline phosphatase at the crossroad of intestinal health and disease - a putative role in type 1 diabetes.

    PubMed

    Lassenius, M I; Fogarty, C L; Blaut, M; Haimila, K; Riittinen, L; Paju, A; Kirveskari, J; Järvelä, J; Ahola, A J; Gordin, D; Härma, M-A; Kumar, A; Hamarneh, S R; Hodin, R A; Sorsa, T; Tervahartiala, T; Hörkkö, S; Pussinen, P J; Forsblom, C; Jauhiainen, M; Taskinen, M-R; Groop, P-H; Lehto, M

    2017-06-01

    Patients with type 1 diabetes have shown an increase in circulating cytokines, altered lipoprotein metabolism and signs of vascular dysfunction in response to high-fat meals. Intestinal alkaline phosphatase (IAP) regulates lipid transport and inflammatory responses in the gastrointestinal tract. We therefore hypothesized that changes in IAP activity could have profound effects on gut metabolic homeostasis in patients with type 1 diabetes. Faecal samples of 41 nondiabetic controls and 46 patients with type 1 diabetes were analysed for IAP activity, calprotectin, immunoglobulins and short-chain fatty acids (SCFAs). The impact of oral IAP supplementation on intestinal immunoglobulin levels was evaluated in C57BL/6 mice exposed to high-fat diet for 11 weeks. Patients with type 1 diabetes exhibited signs of intestinal inflammation. Compared to controls, patients with diabetes had higher faecal calprotectin levels, lower faecal IAP activities accompanied by lower propionate and butyrate concentrations. Moreover, the amount of faecal IgA and the level of antibodies binding to oxidized LDL were decreased in patients with type 1 diabetes. In mice, oral IAP supplementation increased intestinal IgA levels markedly. Deprivation of protective intestinal factors may increase the risk of inflammation in the gut - a phenomenon that seems to be present already in patients with uncomplicated type 1 diabetes. Low levels of intestinal IgA and antibodies to oxidized lipid epitopes may predispose such patients to inflammation-driven complications such as cardiovascular disease and diabetic nephropathy. Importantly, oral IAP supplementation could have beneficial therapeutic effects on gut metabolic homeostasis, possibly through stimulation of intestinal IgA secretion. © 2017 The Association for the Publication of the Journal of Internal Medicine.

  13. PetIGA-MF: A multi-field high-performance toolbox for structure-preserving B-splines spaces

    DOE PAGES

    Sarmiento, Adel; Cortes, Adriano; Garcia, Daniel; ...

    2016-10-07

    We describe the development of a high-performance solution framework for isogeometric discrete differential forms based on B-splines: PetIGA-MF. Built on top of PetIGA, PetIGA-MF is a general multi-field discretization tool. To test the capabilities of our implementation, we solve different viscous flow problems such as Darcy, Stokes, Brinkman, and Navier-Stokes equations. Several convergence benchmarks based on manufactured solutions are presented assuring optimal convergence rates of the approximations, showing the accuracy and robustness of our solver.

  14. The mismatch repair and meiotic recombination endonuclease Mlh1-Mlh3 is activated by polymer formation and can cleave DNA substrates in trans

    PubMed Central

    Manhart, Carol M.; Ni, Xiaodan; White, Martin A.; Ortega, Joaquin; Surtees, Jennifer A.

    2017-01-01

    Crossing over between homologs is initiated in meiotic prophase by the formation of DNA double-strand breaks that occur throughout the genome. In the major interference-responsive crossover pathway in baker’s yeast, these breaks are resected to form 3' single-strand tails that participate in a homology search, ultimately forming double Holliday junctions (dHJs) that primarily include both homologs. These dHJs are resolved by endonuclease activity to form exclusively crossovers, which are critical for proper homolog segregation in Meiosis I. Recent genetic, biochemical, and molecular studies in yeast are consistent with the hypothesis of Mlh1-Mlh3 DNA mismatch repair complex acting as the major endonuclease activity that resolves dHJs into crossovers. However, the mechanism by which the Mlh1-Mlh3 endonuclease is activated is unknown. Here, we provide evidence that Mlh1-Mlh3 does not behave like a structure-specific endonuclease but forms polymers required to generate nicks in DNA. This conclusion is supported by DNA binding studies performed with different-sized substrates that contain or lack polymerization barriers and endonuclease assays performed with varying ratios of endonuclease-deficient and endonuclease-proficient Mlh1-Mlh3. In addition, Mlh1-Mlh3 can generate religatable double-strand breaks and form an active nucleoprotein complex that can nick DNA substrates in trans. Together these observations argue that Mlh1-Mlh3 may not act like a canonical, RuvC-like Holliday junction resolvase and support a novel model in which Mlh1-Mlh3 is loaded onto DNA to form an activated polymer that cleaves DNA. PMID:28453523

  15. Evaluation of natural regulatory T cells in subjects with selective IgA deficiency: from senior idea to novel opportunities.

    PubMed

    Soheili, Habib; Abolhassani, Hassan; Arandi, Narges; Khazaei, Hossein Ali; Shahinpour, Shervin; Hirbod-Mobarakeh, Armin; Rezaei, Nima; Aghamohammadi, Asghar

    2013-01-01

    Selective IgA deficiency (SIgAD) is the most common primary immunodeficiency disorder, which is characterized by significantly decreased serum levels of IgA. Abnormalities of CD4+CD25(high)forkhead box P3 (FoxP3)+ regulatory T cells (T(reg)) have been shown in association with autoimmune and inflammatory disorders. In order to evaluate the relationship between autoimmunity and T(reg) in SIgAD, we studied 26 IgA-deficient patients (aged 4-17 years) with serum IgA levels <7 mg/dl, 26 age- and sex-matched healthy controls and 26 age- and sex matched idiopathic thrombocytopenic purpura cases with normal immune system. T(reg) were determined by flow cytometry using T(reg) markers, including CD4, CD25 and FoxP3. The mean percentage of CD4, CD25+FoxP3+ T(reg) from all CD4+ cells was 4.08 ± 0.86 in healthy controls, which was significantly higher than in SIgAD patients (2.93 ± 1.3; p = 0.003). We set a cutoff point (2.36%) for T(reg), which was two standard deviations lower than the mean of normal controls. According to this cutoff point and in order to assess the role of T(reg) in clinical SIgAD manifestation, we classified patients into two groups: 16 patients in G1 with T(reg) <2.36% and 10 patients in G2 with T(reg) >2.36%. Autoimmunity was recorded in 9 patients (53.3%) of G1 and only 1 patient of G2, respectively (p = 0.034). Although a defect in class switching recombination was observed in 40% of the patients in G1, none of the G2 patients had such a defect (p = 0.028). This study showed decreased proportions of T(reg) in SIgAD patients, particularly in those with signs of chronic inflammation. Copyright © 2012 S. Karger AG, Basel.

  16. Secretory IgA in complex with Lactobacillus rhamnosus potentiates mucosal dendritic cell-mediated Treg cell differentiation via TLR regulatory proteins, RALDH2 and secretion of IL-10 and TGF-β

    PubMed Central

    Mikulic, Josip; Longet, Stéphanie; Favre, Laurent; Benyacoub, Jalil; Corthesy, Blaise

    2017-01-01

    The importance of secretory IgA in controlling the microbiota is well known, yet how the antibody affects the perception of the commensals by the local immune system is still poorly defined. We have previously shown that the transport of secretory IgA in complex with bacteria across intestinal microfold cells results in an association with dendritic cells in Peyer’s patches. However, the consequences of such an interaction on dendritic cell conditioning have not been elucidated. In this study, we analyzed the impact of the commensal Lactobacillus rhamnosus, alone or associated with secretory IgA, on the responsiveness of dendritic cells freshly recovered from mouse Peyer’s patches, mesenteric lymph nodes, and spleen. Lactobacillus rhamnosus-conditioned mucosal dendritic cells are characterized by increased expression of Toll-like receptor regulatory proteins [including single immunoglobulin interleukin-1 receptor-related molecule, suppressor of cytokine signaling 1, and Toll-interacting molecule] and retinaldehyde dehydrogenase 2, low surface expression of co-stimulatory markers, high anti- versus pro-inflammatory cytokine production ratios, and induction of T regulatory cells with suppressive function. Association with secretory IgA enhanced the anti-inflammatory/regulatory Lactobacillus rhamnosus-induced conditioning of mucosal dendritic cells, particularly in Peyer’s patches. At the systemic level, activation of splenic dendritic cells exposed to Lactobacillus rhamnosus was partially dampened upon association with secretory IgA. These data suggest that secretory IgA, through coating of commensal bacteria, contributes to the conditioning of mucosal dendritic cells toward tolerogenic profiles essential for the maintenance of intestinal homeostasis. PMID:26972771

  17. Linear IgA dermatosis associated with ulcerative colitis: complete and sustained remission after total colectomy.

    PubMed

    Vargas, Thiago Jeunon de Sousa; Fialho, Mônica; Santos, Luiza Tavares dos; Rodrigues, Palmira Assis de Jesus Barreto; Vargas, Ana Luisa Bittencourt Sampaio Jeunon; Sousa, Maria Auxiliadora Jeunon

    2013-01-01

    Linear IgA dermatosis has been increasingly associated with inflammatory bowel diseases, particularly ulcerative colitis. A 13-year-old male patient with an 11-month history of ulcerative colitis developed vesicles, pustules and erosions on the skin of the face, trunk and buttocks and in the oral mucosa. The work-up revealed a neutrophil-rich sub-epidermal bullous disease and linear deposition of IgA along the dermoepidermal junction, establishing the diagnosis of linear IgA dermatosis. The patient experienced unsatisfactory partial control of skin and intestinal symptoms despite the use of adalimumab, mesalazine, prednisone and dapsone for some months. After total colectomy, he presented complete remission of skin lesions, with no need of medications during two years of follow-up. A review of previously reported cases of the association is provided here and the role of ulcerative colitis in triggering linear IgA dermatosis is discussed.

  18. Implications of caspase-dependent proteolytic cleavage of cyclin A1 in DNA damage-induced cell death

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woo, Sang Hyeok; Seo, Sung-Keum; An, Sungkwan

    Highlights: • Caspase-1 mediates doxorubicin-induced downregulation of cyclin A1. • Active caspase-1 effectively cleaved cyclin A1 at D165. • Cyclin A1 expression is involved in DNA damage-induced cell death. - Abstract: Cyclin A1 is an A-type cyclin that directly binds to CDK2 to regulate cell-cycle progression. In the present study, we found that doxorubicin decreased the expression of cyclin A1 at the protein level in A549 lung cancer cells, while markedly downregulating its mRNA levels. Interestingly, doxorubicin upregulated caspase-1 in a concentration-dependent manner, and z-YAVD-fmk, a specific inhibitor of caspase-1, reversed the doxorubicin-induced decrease in cyclin A1 in A549 lungmore » cancer and MCF7 breast cancer cells. Active caspase-1 effectively cleaved cyclin A1 at D165 into two fragments, which in vitro cleavage assays showed were further cleaved by caspase-3. Finally, we found that overexpression of cyclin A1 significantly reduced the cytotoxicity of doxorubicin, and knockdown of cyclin A1 by RNA interference enhanced the sensitivity of cells to ionizing radiation. Our data suggest a new mechanism for the downregulation of cyclin A1 by DNA-damaging stimuli that could be intimately involved in the cell death induced by DNA damage-inducing stimuli, including doxorubicin and ionizing radiation.« less

  19. Radiolabelled polymeric IgA: from biodistribution to a new molecular imaging tool in colorectal cancer lung metastases

    PubMed Central

    Carpenet, Helene; Cuvillier, Armelle; Perraud, Aurélie; Martin, Ophélie; Champier, Gaël; Jauberteau, Marie-Odile; Monteil, Jacques; Quelven, Isabelle

    2017-01-01

    By radiolabelling monomeric (m) and polymeric (p) IgA with technetium 99m (99mTc), this study assessed IgA biodistribution and tumour-targeting potency. IgA directed against carcinoembryonic antigen (CEA), a colorectal cancer marker, was selected to involve IgA mucosal tropism. Ig was radiolabelled with 99mTc-tricarbonyl after derivatisation by 2-iminothiolane. 99mTc-IgA was evaluated by in vitro analysis. The biodistributions of radiolabelled anti-CEA mIgA, pIgA and IgG were compared in normal mice. Anti-CEA pIgA tumour uptake was studied in mice bearing the WiDr caecal orthotopic graft. IgA radiolabelling was obtained with a high yield, was stable in PBS and murine plasma, and did not alter IgA binding functionality (Kd ≈ 25 nM). Biodistribution studies in normal mice confirmed that radiolabelled pIgA – and to a lesser extent, mIgA – showed strong and fast mucosal tropism and a shorter serum half-life than IgG. In caecal tumour model mice, evaluation of the anti-CEA-pIgA biodistribution showed a high uptake in lung metastases, confirmed by histological analysis. However, no radioactivity uptake increase in the tumoural caecum was discerned from normal intestinal tissue, probably due to high IgA caecal natural tropism. In microSPECT/CT imaging, 99mTc-IgA confirmed its diagnostic potency of tumour in mucosal tissue, even if detection threshold by in vivo imaging was higher than post mortem studies. Contribution of the FcαRI receptor, studied with transgenic mouse model (Tsg SCID-CD89), did not appear to be determinant in 99mTc-IgA uptake. Pre-clinical experiments highlighted significant differences between 99mTc-IgA and 99mTc-IgG biodistributions. Furthermore, tumoural model studies suggested potential targeting potency of pIgA in mucosal tissues. PMID:29156712

  20. Characterization of a monoclonal antibody against P57, the C3/C3b-cleaving proteinase expressed in human erythrocyte membranes.

    PubMed

    Fiandino-Tirel, A; Barel, M; Lyamani, F; Gauffre, A; Hermann, J; Frade, R

    1991-08-01

    A monoclonal antibody was raised against p57, a serine proteinase, characterized by an apparent molecular weight of 57 kDa, and purified from human erythrocyte membranes. P57 proteinase cleaves the human third component of complement, C3. The antibody selected, MP1, of IgG2a isotype, precipitated specifically the p57 antigen which carried the C3/C3b-cleaving activity present in membrane crude extract of human erythrocytes. P57 proteinase eluted from MP1-sepharose was inhibited by 5 x 10(-4) M PMSF, enhanced by 0.5% SDS and generated C3 fragments identical to those generated by membrane crude extract of human erythrocytes. All these properties were identical to those of the p57 previously purified by biochemical procedures. In addition, 5000 binding sites were detected on cell surface. This MP1 monoclonal antibody will be helpful to analyse the role of p57 in human erythrocytes.

  1. Chemoprevention of Skin Cancer with 1,1-Bis (3′-Indolyl)-1-(Aromatic) Methane Analog through Induction of the Orphan Nuclear Receptor, NR4A2 (Nurr1)

    PubMed Central

    Shah, Punit P.; Patel, Apurva R.; Godugu, Chandraiah; Safe, Stephen; Katiyar, Santosh K.; Singh, Mandip

    2013-01-01

    Background The objective of this study was to demonstrate the anti-skin cancer and chemopreventive potential of 1,1-bis(3′-indolyl)-1-(p-chlorophenyl methane) (DIM-D) using an in vitro model. Methods In vitro cell cytotoxicity and viability assays were carried out in A431 human epidermoid carcinoma cell line and normal human epidermal keratinocytes (NHEK) respectively by crystal violet staining. Apoptosis induction in A431 cells (DIM-D treated) and NHEK cells pretreated with DIM-D (2 hr) prior to UVB irradiation, were assessed. The accumulation of reactive oxygen species (ROS) in DIM-D pretreated NHEK cells (2 hr) prior to UVB exposure was also determined. Immunocytochemistry and western blot analysis was performed to determine cleaved caspase 3 and DNA damage markers in DIM-D treated A431 cells and in DIM-D pretreated NHEK cells prior to UVB irradiation. Results The IC50 values of DIM-D were 68.7±7.3, 48.3±10.1 and 11.5±3.1 μM whilst for Epigallocatechin gallate (EGCG) were 419.1±8.3, 186.1±5.2 and 56.7±3.1 μM for 24, 48 and 72 hr treatments respectively. DIM-D exhibited a significantly (p<0.05) greater induction of DNA fragmentation in A431 cells compared to EGCG with percent cell death of 38.9. In addition, DIM-D induced higher expression in A431 cells compared to EGCG of cleaved caspase 3 (3.0-fold vs. 2.4-fold changes), Nurr1 (2.7-fold vs. 1.7-fold changes) and NFκB (1.3-fold vs. 1.1-fold changes). DIM-D also exhibited chemopreventive activity in UVB-irradiated NHEK cells by significantly (p<0.05) reducing UVB-induced ROS formation and apoptosis compared to EGCG. Additionally, DIM-D induced expression of Nurr1 but reduced expression of 8-OHdG significantly in UVB-irradiated NHEK cells compared to EGCG and UV only. Conclusion Our results suggest that DIM-D exhibits Nurr1-dependent transactivation in the induction of apoptosis in A431 cells and it protects NHEK cells against UVB-induced ROS formation and DNA damage. PMID:23950896

  2. What do anti-Toxoplasma gondii IgA and IgG subclasses in human saliva indicate?

    PubMed

    Cañedo-Solares, I; Gómez-Chávez, F; Luna-Pastén, H; Ortiz-Alegría, L B; Flores-García, Y; Figueroa-Damián, R; Macedo-Romero, C A; Correa, D

    2018-05-01

    Diagnostic tests for toxoplasmosis are based on serological techniques due to their high sensitivity. Some IgG subclasses are related to clinical outcome in the congenital form. In this work, we determined the levels of IgG, IgA, IgG1, IgG2, IgG3 and IgG4 anti-Toxoplasma gondii antibodies in paired saliva and serum samples from 91 women by indirect ELISA using a crude extract of the RH strain. The levels of IgA, IgG2, IgG3 and IgG4 antibodies and, to a lesser extent, IgG1 did not correlate between saliva and serum, that is, most cases that were positive for one Ig class in a sample were negative or very low in the other, and vice versa. We also observed that most samples of saliva that were positive for one IgG subclass were also positive for at least 2 of the other 3; this contrasted with findings in serum, wherein each person was positive almost exclusively for one subclass, as demonstrated before by us and other researchers. Although these findings are disappointing for the use in diagnosis, the richer response in saliva might indicate local exposure to T. gondii antigens without systemic infection; thus, saliva might be reflecting a local (protective?) response against this protozoan. © 2018 John Wiley & Sons Ltd.

  3. Measurement of neutralizing serum antibodies of patients vaccinated with human papillomavirus L1 or L2-based immunogens using furin-cleaved HPV Pseudovirions.

    PubMed

    Wang, Joshua W; Jagu, Subhashini; Wang, Chenguang; Kitchener, Henry C; Daayana, Sai; Stern, Peter L; Pang, Susana; Day, Patricia M; Huh, Warner K; Roden, Richard B S

    2014-01-01

    Antibodies specific for neutralizing epitopes in either Human papillomavirus (HPV) capsid protein L1 or L2 can mediate protection from viral challenge and thus their accurate and sensitive measurement at high throughput is likely informative for monitoring response to prophylactic vaccination. Here we compare measurement of L1 and L2-specific neutralizing antibodies in human sera using the standard Pseudovirion-Based Neutralization Assay (L1-PBNA) with the newer Furin-Cleaved Pseudovirion-Based Neutralization Assay (FC-PBNA), a modification of the L1-PBNA intended to improve sensitivity towards L2-specific neutralizing antibodies without compromising assay of L1-specific responses. For detection of L1-specific neutralizing antibodies in human sera, the FC- PBNA and L1-PBNA assays showed similar sensitivity and a high level of correlation using WHO standard sera (n = 2), and sera from patients vaccinated with Gardasil (n = 30) or an experimental human papillomavirus type 16 (HPV16) L1 VLP vaccine (n = 70). The detection of L1-specific cross-neutralizing antibodies in these sera using pseudovirions of types phylogenetically-related to those targeted by the L1 virus-like particle (VLP) vaccines was also consistent between the two assays. However, for sera from patients (n = 17) vaccinated with an L2-based immunogen (TA-CIN), the FC-PBNA was more sensitive than the L1-PBNA in detecting L2-specific neutralizing antibodies. Further, the neutralizing antibody titers measured with the FC-PBNA correlated with those determined with the L2-PBNA, another modification of the L1-PBNA that spacio-temporally separates primary and secondary receptor engagement, as well as the protective titers measured using passive transfer studies in the murine genital-challenge model. In sum, the FC-PBNA provided sensitive measurement for both L1 VLP and L2-specific neutralizing antibody in human sera. Vaccination with TA-CIN elicits weak cross-protective antibody in a subset of

  4. Factors associated with fluctuations in IgA and IgG levels at the cervix during the menstrual cycle.

    PubMed

    Safaeian, Mahboobeh; Falk, Roni T; Rodriguez, Ana Cecilia; Hildesheim, Allan; Kemp, Troy; Williams, Marcus; Morera, Lidiana; Barrantes, Manuel; Herrero, Rolando; Porras, Carolina; Pinto, Ligia

    2009-02-01

    The objective of this analysis was to describe patterns and determinants of cervical immunoglobulin A (IgA) and G (IgG) levels during the menstrual cycle. A total of 154 women who attended 3 visits coinciding with the follicular, periovulatory, and luteal phases of their menstrual cycle were studied. Cervical secretions were collected at each visit for determination of total IgA and IgG levels. Questionnaires administered at each visit inquired about demographic characteristics and behavioral practices. Total IgA and IgG levels were higher among oral contraceptive (OC) users than among naturally cycling women (hereafter, "non-OC users"). IgA and IgG levels decreased at midcycle, particularly among non-OC users. After adjustment for phase of the current cycle, specimen weight, and detection of blood in the sample, report of a recent illness was associated with lower IgA and IgG levels and increased age with higher IgA and IgG levels among OC users and non-OC users. Increased lifetime number of pregnancies was associated with a higher IgA level among non-OC users and a higher IgG level among OC users. Change in immunoglobulin levels between visits was associated with sample weight and the presence of blood for both OC users and non-OC users. Phase of the current menstrual cycle and OC use were significant determinants of cervical IgA and IgG levels. The impacts of endogenous and exogenous hormones on cervical immunoglobulin levels should be further investigated.

  5. Purification, crystallization and X-ray diffraction analysis of a novel ring-cleaving enzyme (BoxC{sub C}) from Burkholderia xenovorans LB400

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bains, Jasleen; Boulanger, Martin J., E-mail: mboulang@uvic.ca

    2008-05-01

    Preliminary X-ray diffraction studies of a novel ring-cleaving enzyme from B. xenovorans LB400 encoded by the benzoate-oxidation (box) pathway. The assimilation of aromatic compounds by microbial species requires specialized enzymes to cleave the thermodynamically stable ring. In the recently discovered benzoate-oxidation (box) pathway in Burkholderia xenovorans LB400, this is accomplished by a novel dihydrodiol lyase (BoxC{sub C}). Sequence analysis suggests that BoxC{sub C} is part of the crotonase superfamily but includes an additional uncharacterized region of approximately 115 residues that is predicted to mediate ring cleavage. Processing of X-ray diffraction data to 1.5 Å resolution revealed that BoxC{sub C} crystallizedmore » with two molecules in the asymmetric unit of the P2{sub 1}2{sub 1}2{sub 1} space group, with a solvent content of 47% and a Matthews coefficient of 2.32 Å{sup 3} Da{sup −1}. Selenomethionine BoxC{sub C} has been purified and crystals are currently being refined for anomalous dispersion studies.« less

  6. Detection of a combination of serum IgG and IgA antibodies against selected mycobacterial targets provides promising diagnostic signatures for active TB

    PubMed Central

    Chegou, Novel N.; Kriel, Belinda; Jacobs, Ruschca; Kidd, Martin; Loxton, Andre G.; Kaempfer, Susanne; Singh, Mahavir; Walzl, Gerhard

    2017-01-01

    Immunoglobulin G (IgG) based tests for the diagnosis of active tuberculosis (TB) disease often show a lack of specificity in TB endemic regions, which is mainly due to a high background prevalence of LTBI. Here, we investigated the combined performance of the responses of different Ig classes to selected mycobacterial antigens in primary healthcare clinic attendees with signs and symptoms suggestive of TB. The sensitivity and specificity of IgA, IgG and/or IgM to LAM and 7 mycobacterial protein antigens (ESAT-6, Tpx, PstS1, AlaDH, MPT64, 16kDa and 19kDa) and 2 antigen combinations (TUB, TB-LTBI) in the plasma of 63 individuals who underwent diagnostic work-up for TB after presenting with symptoms and signs compatible with possible active TB were evaluated. Active TB was excluded in 42 individuals of whom 21 has LTBI whereas active TB was confirmed in 21 patients of whom 19 had a follow-up blood draw at the end of 6-month anti-TB treatment. The leading single serodiagnostic markers to differentiate between the presence or absence of active TB were anti-16 kDa IgA, anti-MPT64 IgA with sensitivity and specificity of 90%/90% and 95%/90%, respectively. The combined use of 3 or 4 antibodies further improved this performance to accuracies above 95%. After successful completion of anti-TB treatment at month 6, the levels of 16 kDa IgA and 16 kDa IgM dropped significantly whereas LAM IgG and TB-LTBI IgG increased. These results show the potential of extending investigation of anti-tuberculous IgG responses to include IgM and IgA responses against selected protein and non-protein antigens in differentiating active TB from other respiratory diseases in TB endemic settings. PMID:28415587

  7. Detection of a combination of serum IgG and IgA antibodies against selected mycobacterial targets provides promising diagnostic signatures for active TB.

    PubMed

    Awoniyi, Dolapo O; Baumann, Ralf; Chegou, Novel N; Kriel, Belinda; Jacobs, Ruschca; Kidd, Martin; Loxton, Andre G; Kaempfer, Susanne; Singh, Mahavir; Walzl, Gerhard

    2017-06-06

    Immunoglobulin G (IgG) based tests for the diagnosis of active tuberculosis (TB) disease often show a lack of specificity in TB endemic regions, which is mainly due to a high background prevalence of LTBI. Here, we investigated the combined performance of the responses of different Ig classes to selected mycobacterial antigens in primary healthcare clinic attendees with signs and symptoms suggestive of TB. The sensitivity and specificity of IgA, IgG and/or IgM to LAM and 7 mycobacterial protein antigens (ESAT-6, Tpx, PstS1, AlaDH, MPT64, 16kDa and 19kDa) and 2 antigen combinations (TUB, TB-LTBI) in the plasma of 63 individuals who underwent diagnostic work-up for TB after presenting with symptoms and signs compatible with possible active TB were evaluated. Active TB was excluded in 42 individuals of whom 21 has LTBI whereas active TB was confirmed in 21 patients of whom 19 had a follow-up blood draw at the end of 6-month anti-TB treatment. The leading single serodiagnostic markers to differentiate between the presence or absence of active TB were anti-16 kDa IgA, anti-MPT64 IgA with sensitivity and specificity of 90%/90% and 95%/90%, respectively. The combined use of 3 or 4 antibodies further improved this performance to accuracies above 95%. After successful completion of anti-TB treatment at month 6, the levels of 16 kDa IgA and 16 kDa IgM dropped significantly whereas LAM IgG and TB-LTBI IgG increased. These results show the potential of extending investigation of anti-tuberculous IgG responses to include IgM and IgA responses against selected protein and non-protein antigens in differentiating active TB from other respiratory diseases in TB endemic settings.

  8. IgA nephropathy in systemic lupus erythematosus patients: case report and literature review.

    PubMed

    da Silva, Leonardo Sales; Almeida, Bruna Laiza Fontes; de Melo, Ana Karla Guedes; de Brito, Danielle Christine Soares Egypto; Braz, Alessandra Sousa; Freire, Eutília Andrade Medeiros

    2016-01-01

    Systemic erythematosus lupus (SLE) is a multisystemic autoimmune disease which has nephritis as one of the most striking manifestations. Although it can coexist with other autoimmune diseases, and determine the predisposition to various infectious complications, SLE is rarely described in association with non-lupus nephropathies etiologies. We report the rare association of SLE and primary IgA nephropathy (IgAN), the most frequent primary glomerulopathy in the world population. The patient was diagnosed with SLE due to the occurrence of malar rash, alopecia, pleural effusion, proteinuria, ANA 1: 1280, nuclear fine speckled pattern, and anticardiolipin IgM and 280U/mL. Renal biopsy revealed mesangial hypercellularity with isolated IgA deposits, consistent with primary IgAN. It was treated with antimalarial drug, prednisone and inhibitor of angiotensin converting enzyme, showing good progress. Since they are relatively common diseases, the coexistence of SLE and IgAN may in fact be an uncommon finding for unknown reasons or an underdiagnosed condition. This report focus on the importance of the distinction between the activity of renal disease in SLE and non-SLE nephropathy, especially IgAN, a definition that has important implications on renal prognosis and therapeutic regimens to be adopted in both the short and long terms. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  9. Toxin MqsR Cleaves Single-Stranded mRNA with Various 5 Ends

    DTIC Science & Technology

    2016-08-24

    either protein ORIGINAL RESEARCH Toxin MqsR cleaves single- stranded mRNA with various 5’ ends Nityananda Chowdhury1,*, Brian W. Kwan1,*, Louise C...in which a single 5′- GCU site was predicted to be single- stranded (ssRNA), double- stranded (dsRNA), in the loop of a stem - loop (slRNA), or in a...single- stranded 5′- GCU sites since cleavage was approximately 20- fold higher than cleavage seen with the 5′- GCU site in the stem - loop and

  10. Agonists of proteinase-activated receptor 1 induce plasma extravasation by a neurogenic mechanism.

    PubMed

    de Garavilla, L; Vergnolle, N; Young, S H; Ennes, H; Steinhoff, M; Ossovskaya, V S; D'Andrea, M R; Mayer, E A; Wallace, J L; Hollenberg, M D; Andrade-Gordon, P; Bunnett, N W

    2001-08-01

    Thrombin, generated in the circulation during injury, cleaves proteinase-activated receptor 1 (PAR1) to stimulate plasma extravasation and granulocyte infiltration. However, the mechanism of thrombin-induced inflammation in intact tissues is unknown. We hypothesized that thrombin cleaves PAR1 on sensory nerves to release substance P (SP), which interacts with the neurokinin 1 receptor (NK1R) on endothelial cells to cause plasma extravasation. PAR1 was detected in small diameter neurons known to contain SP in rat dorsal root ganglia by immunohistochemistry and in situ hybridization. Thrombin and the PAR1 agonist TFLLR-NH(2) (TF-NH(2)) increased [Ca(2+)](i) >50% of cultured neurons (EC(50)s 24 mu ml(-1) and 1.9 microM, respectively), assessed using Fura-2 AM. The PAR1 agonist completely desensitized responses to thrombin, indicating that thrombin stimulates neurons through PAR1. Injection of TF-NH(2) into the rat paw stimulated a marked and sustained oedema. An NK1R antagonist and ablation of sensory nerves with capsaicin inhibited oedema by 44% at 1 h and completely by 5 h. In wild-type but not PAR1(-/-) mice, TF-NH(2) stimulated Evans blue extravasation in the bladder, oesophagus, stomach, intestine and pancreas by 2 - 8 fold. Extravasation in the bladder, oesophagus and stomach was abolished by an NK1R antagonist. Thus, thrombin cleaves PAR1 on primary spinal afferent neurons to release SP, which activates the NK1R on endothelial cells to stimulate gap formation, extravasation of plasma proteins, and oedema. In intact tissues, neurogenic mechanisms are predominantly responsible for PAR1-induced oedema.

  11. 2A self-cleaving peptide-based multi-gene expression system in the silkworm Bombyx mori

    PubMed Central

    Wang, Yuancheng; Wang, Feng; Wang, Riyuan; Zhao, Ping; Xia, Qingyou

    2015-01-01

    Fundamental and applied studies of silkworms have entered the functional genomics era. Here, we report a multi-gene expression system (MGES) based on 2A self-cleaving peptide (2A), which regulates the simultaneous expression and cleavage of multiple gene targets in the silk gland of transgenic silkworms. First, a glycine-serine-glycine spacer (GSG) was found to significantly improve the cleavage efficiency of 2A. Then, the cleavage efficiency of six types of 2As with GSG was analyzed. The shortest porcine teschovirus-1 2A (P2A-GSG) exhibited the highest cleavage efficiency in all insect cell lines that we tested. Next, P2A-GSG successfully cleaved the artificial human serum albumin (66 kDa) linked with human acidic fibroblast growth factor (20.2 kDa) fusion genes and vitellogenin receptor fragment (196 kD) of silkworm linked with EGFP fusion genes, importantly, vitellogenin receptor protein was secreted to the outside of cells. Furthermore, P2A-GSG successfully mediated the simultaneous expression and cleavage of a DsRed and EGFP fusion gene in silk glands and caused secretion into the cocoon of transgenic silkworms using our sericin1 expression system. We predicted that the MGES would be an efficient tool for gene function research and innovative research on various functional silk materials in medicine, cosmetics, and other biomedical areas. PMID:26537835

  12. Bleomycin Can Cleave an Oncogenic Noncoding RNA.

    PubMed

    Angelbello, Alicia J; Disney, Matthew D

    2018-01-04

    Noncoding RNAs are pervasive in cells and contribute to diseases such as cancer. A question in biomedical research is whether noncoding RNAs are targets of medicines. Bleomycin is a natural product that cleaves DNA; however, it is known to cleave RNA in vitro. Herein, an in-depth analysis of the RNA cleavage preferences of bleomycin A5 is presented. Bleomycin A5 prefers to cleave RNAs with stretches of AU base pairs. Based on these preferences and bioinformatic analysis, the microRNA-10b hairpin precursor was identified as a potential substrate for bleomycin A5. Both in vitro and cellular experiments demonstrated cleavage. Importantly, chemical cleavage by bleomycin A5 in the microRNA-10b hairpin precursors occurred near the Drosha and Dicer enzymatic processing sites and led to destruction of the microRNA. Evidently, oncogenic noncoding RNAs can be considered targets of cancer medicines and might elicit their pharmacological effects by targeting noncoding RNA. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Bacteroides induce higher IgA production than Lactobacillus by increasing activation-induced cytidine deaminase expression in B cells in murine Peyer's patches.

    PubMed

    Yanagibashi, Tsutomu; Hosono, Akira; Oyama, Akihito; Tsuda, Masato; Hachimura, Satoshi; Takahashi, Yoshimasa; Itoh, Kikuji; Hirayama, Kazuhiro; Takahashi, Kyoko; Kaminogawa, Shuichi

    2009-02-01

    The gut mucosal immune system is crucial in host defense against infection by pathogenic microbacteria and viruses via the production of IgA. Previous studies have shown that intestinal commensal bacteria enhance mucosal IgA production. However, it is poorly understood how these bacteria induce IgA production and which genera of intestinal commensal bacteria induce IgA production effectively. In this study, we compared the immunomodulatory effects of Bacteroides and Lactobacillus on IgA production by Peyer's patches lymphocytes. IgA production by Peyer's patches lymphocytes co-cultured with Bacteroides was higher than with Lactobacillus. In addition, the expression of activation-induced cytidine deaminase increased in co-culture with Bacteroides but not with Lactobacillus. We found that intestinal commensal bacteria elicited IgA production. In particular, Bacteroides induced the differentiation of Peyer's patches B cell into IgA(+) B cells by increasing activation-induced cytidine deaminase expression.

  14. Intermittent fasting modulates IgA levels in the small intestine under intense stress: a mouse model.

    PubMed

    Lara-Padilla, Eleazar; Godínez-Victoria, Marycarmen; Drago-Serrano, Maria Elisa; Reyna-Garfias, Humberto; Arciniega-Martínez, Ivonne Maciel; Abarca-Rojano, Edgar; Cruz-Hernández, Teresita Rocío; Campos-Rodríguez, Rafael

    2015-08-15

    Intermittent fasting prolongs the lifespan and unlike intense stress provides health benefits. Given the role of the immunoglobulin A (IgA) in the intestinal homeostasis, the aim of this study was to assess the impact of intermittent fasting plus intense stress on secretory IgA (SIgA) production and other mucosal parameters in the duodenum and ileum. Two groups of six mice, with intermittent fasting or fed ad libitum for 12weeks, were submitted to a session of intense stress by a bout of forced swimming. Unstressed ad libitum fed or intermittently fasted groups were included as controls. After sacrifice, we evaluated intestinal SIgA and plasma adrenal hormones, lamina propria IgA+ plasma-cells, mRNA expression of polymeric immunoglobulin receptor, α- and J-chains in the liver and intestinal mucosa, as well as pro- (tumor necrosis factor-α, interleukin-6 and Interferon-γ) and anti- (interleukin-2, -4, -10 and transforming growth factor-β) inflammatory cytokines in mucosal samples. Under intense stress, intermittent fasting down- or up-modulated the levels of most parameters in the duodenum and ileum, respectively while up-regulated corticosterone levels without affecting epinephrine. Our data suggest intermittent fasting plus intense stress elicited neuroendocrine pathways that differentially controlled IgA and pIgR expression in duodenum and ileum. These findings provide experimental foundations for a presumable impact of intermittent fasting under intense stress on the intestinal homeostasis or inflammation by triggering or reducing the IgA production in ileum or duodenum respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Gastrointestinal sensitivity to soy and milk proteins in patients with IgA nephropathy.

    PubMed

    Kloster Smerud, H; Fellström, B; Hällgren, R; Osagie, S; Venge, P; Kristjánsson, G

    2010-11-01

    sensitivity to food antigens has been postulated as a contributing factor to the pathogenesis of IgA nephropathy (IgAN). in this study we used a recently developed mucosal patch technique to evaluate rectal mucosal sensitivity to soy and cow's milk (CM) proteins in IgAN patients (n = 28) compared to healthy subjects (n = 18). The rectal mucosal production of nitric oxide (NO) and release of myeloperoxidase (MPO) and eosinophil cationic protein (ECP) were measured. Serum samples were analyzed for IgA and IgG antibodies to alpha-lactalbumin, beta-lactoglobulin, casein and soy. 14 of 28 (14/28) patients experienced a rectal mucosal reaction, measured by increased NO and/or MPO levels, upon rectal challenge with soy and/or cow's milk proteins. The levels of IgG antibodies to alpha-lactalbumin, beta-lactoglobulin and casein were significantly higher in CM sensitive as compared with non-sensitive IgAN patients, whereas the mean serum levels of IgA antibodies were similar. No differences were seen in serum levels of IgA or IgG antibodies to soy. it is concluded that approximately half of our IgAN patients have a rectal mucosal sensitivity to soy or CM, and that an immune reactivity against antigens may be involved in the pathogenesis of IgAN in this subgroup of patients.

  16. An IgaA/UmoB Family Protein from Serratia marcescens Regulates Motility, Capsular Polysaccharide Biosynthesis, and Secondary Metabolite Production.

    PubMed

    Stella, Nicholas A; Brothers, Kimberly M; Callaghan, Jake D; Passerini, Angelina M; Sigindere, Cihad; Hill, Preston J; Liu, Xinyu; Wozniak, Daniel J; Shanks, Robert M Q

    2018-03-15

    Secondary metabolites are an important source of pharmaceuticals and key modulators of microbe-microbe interactions. The bacterium Serratia marcescens is part of the Enterobacteriaceae family of eubacteria and produces a number of biologically active secondary metabolites. In this study, we screened for novel regulators of secondary metabolites synthesized by a clinical isolate of S. marcescens and found mutations in a gene for an uncharacterized UmoB/IgaA family member here named gumB Mutation of gumB conferred a severe loss of the secondary metabolites prodigiosin and serratamolide. The gumB mutation conferred pleiotropic phenotypes, including altered biofilm formation, highly increased capsular polysaccharide production, and loss of swimming and swarming motility. These phenotypes corresponded to transcriptional changes in fimA , wecA , and flhD Unlike other UmoB/IgaA family members, gumB was found to be not essential for growth in S. marcescens , yet igaA from Salmonella enterica , yrfF from Escherichia coli , and an uncharacterized predicted ortholog from Klebsiella pneumoniae complemented the gumB mutant secondary metabolite defects, suggesting highly conserved function. These data support the idea that UmoB/IgaA family proteins are functionally conserved and extend the known regulatory influence of UmoB/IgaA family proteins to the control of competition-associated secondary metabolites and biofilm formation. IMPORTANCE IgaA/UmoB family proteins are found in members of the Enterobacteriaceae family of bacteria, which are of environmental and public health importance. IgaA/UmoB family proteins are thought to be inner membrane proteins that report extracellular stresses to intracellular signaling pathways that respond to environmental challenge. This study introduces a new member of the IgaA/UmoB family and demonstrates a high degree of functional similarity between IgaA/UmoB family proteins. Moreover, this study extends the phenomena controlled by IgaA

  17. A human papillomavirus type 16 vaccine by oral delivery of L1 protein.

    PubMed

    Sasagawa, Toshiyuki; Tani, Mayuko; Basha, Walid; Rose, Robert C; Tohda, Hideki; Giga-Hama, Yuko; Azar, Khadijeh K; Yasuda, Hideyo; Sakai, Akemi; Inoue, Masaki

    2005-06-01

    To establish an edible HPV16 vaccine, we constructed a recombinant HPV16 L1-expressing Schizosaccharomyces pombe yeast strain (HPV16L1 yeast). A preliminary study revealed that freeze-dried yeast cells could be delivered safely, and were digested in the mouse intestine. The freeze-dried HPV16 L1 yeast was administered orally as an edible vaccine, with or without the mucosal adjuvant heat-labile toxin LT (R192G), to 18 female BALB/c mice. After the third immunization, none of the mice that received the edible HPV16 vaccine showed specific antibody responses, whereas all of the positive controls that were administered intranasally with 5 microg of HPV16-virus-like particles (VLP) had serum IgG, and genital IgA and IgG that reacted with HPV16-VLP in enzyme-linked immunosorbent assays (ELISAs). When a suboptimal dose (1 microg) of HPV16-VLP was administered to all the mice, including the negative control mice, 50% of the mice that were pre-immunized with the edible HPV16 vaccine showed positive serum IgG responses, while none of the negative controls showed any response. Vaginal IgG and IgA antibodies were also elicited in 33 and 39%, respectively, of the mice that were given with the edible HPV16 vaccine and the intranasal boost. All of the antibodies reacted more strongly to intact HPV16-VLP than to denatured HPV16-L1 protein suggesting that the edible vaccine primes for antibody responses against conformation-dependent epitopes. The inclusion of adjuvant in the vaccine formulation marginally increased the genital IgA response (P=0.06). HPV16-L1 protein in the yeast might induce tolerance in the vaccinated animals that could be recovered by intranasal boosting with a suboptimal dose of HPV-VLP. This freeze-dried yeast system may be useful as an oral delivery of HPV 16 L1 protein.

  18. Different Dynamics for IgG and IgA Memory B Cells in Adolescents following a Meningococcal Serogroup C Tetanus Toxoid Conjugate Booster Vaccination Nine Years after Priming: A Role for Priming Age?

    PubMed Central

    Stoof, Susanne P.; Buisman, Anne-Marie; van Rooijen, Debbie M.; Boonacker, Rianne; van der Klis, Fiona R. M.; Sanders, Elisabeth A. M.; Berbers, Guy A. M.

    2015-01-01

    Background Antibody levels wane rapidly after Meningococcal serogroup C conjugate (MenCC) vaccination in young children, rendering the need for an adolescent booster dose. It is not clear whether circulating memory B cells are associated with persistence of MenC-specific antibody levels. Methods Measurement of MenC-specific IgG and IgA memory B cells and levels of serum and salivary MenC-specific IgG and IgA in healthy 10-, 12- and 15-year-olds prior to and one month and one year after a MenCC booster vaccination. All participants had received a primary MenCC vaccination nine years earlier. Results The number of circulating MenC-specific IgG memory B cells prior to booster was low and not predictive for MenC-specific IgG responses in serum or saliva post-booster, whereas the number of MenC-specific IgA memory B cells pre-booster positively correlated with MenC-specific IgA levels in saliva post-booster (R = 0.5, P<0.05). The booster induced a clear increase in the number of MenC-specific IgG and IgA memory B cells. The number of MenC-PS-specific IgG memory B cells at 1 month post-booster was highest in the 12-year-olds. The number of MenC-specific memory B cells at one month post-booster showed no correlation with the rate of MenC-specific antibody decay throughout the first year post-booster. Conclusions Circulating MenC-specific IgA memory B cells correlate with IgA responses in saliva, whereas circulating MenC-specific IgG memory B cells are not predictive for MenC-specific IgG responses in serum or saliva. Our results are suggestive for age-dependent differences in pre-existing memory against MenC. PMID:26458006

  19. Different Dynamics for IgG and IgA Memory B Cells in Adolescents following a Meningococcal Serogroup C Tetanus Toxoid Conjugate Booster Vaccination Nine Years after Priming: A Role for Priming Age?

    PubMed

    Stoof, Susanne P; Buisman, Anne-Marie; van Rooijen, Debbie M; Boonacker, Rianne; van der Klis, Fiona R M; Sanders, Elisabeth A M; Berbers, Guy A M

    2015-01-01

    Antibody levels wane rapidly after Meningococcal serogroup C conjugate (MenCC) vaccination in young children, rendering the need for an adolescent booster dose. It is not clear whether circulating memory B cells are associated with persistence of MenC-specific antibody levels. Measurement of MenC-specific IgG and IgA memory B cells and levels of serum and salivary MenC-specific IgG and IgA in healthy 10-, 12- and 15-year-olds prior to and one month and one year after a MenCC booster vaccination. All participants had received a primary MenCC vaccination nine years earlier. The number of circulating MenC-specific IgG memory B cells prior to booster was low and not predictive for MenC-specific IgG responses in serum or saliva post-booster, whereas the number of MenC-specific IgA memory B cells pre-booster positively correlated with MenC-specific IgA levels in saliva post-booster (R = 0.5, P<0.05). The booster induced a clear increase in the number of MenC-specific IgG and IgA memory B cells. The number of MenC-PS-specific IgG memory B cells at 1 month post-booster was highest in the 12-year-olds. The number of MenC-specific memory B cells at one month post-booster showed no correlation with the rate of MenC-specific antibody decay throughout the first year post-booster. Circulating MenC-specific IgA memory B cells correlate with IgA responses in saliva, whereas circulating MenC-specific IgG memory B cells are not predictive for MenC-specific IgG responses in serum or saliva. Our results are suggestive for age-dependent differences in pre-existing memory against MenC.

  20. Natural Immunoreactivity of Secretory IgA to Indigenous Strains of Streptococcus mutans From Chinese Spousal Pairs

    PubMed Central

    Nie, Min; Chen, Dong; Gao, Zhenyan; Wu, Xinyu; Li, Tong

    2016-01-01

    Background Dental caries is a well-known biofilm-mediated disease initiated by Streptococcus mutans, which should infect and colonize in a milieu perfused with components of the mucosal immune system. Little is known, however, regarding the relationship between the natural secretory IgA activity and S. mutans of a variety of diverse genotypes. Objectives The current study aimed to use spousal pairs to investigate the natural immunoreactivity of salivary secretory IgA to different genotype strains of S. mutans. Patients and Methods Indigenous strains were characterized from nine spousal pairs using polymerase reaction chain (PCR) and arbitrarily primed polymerase chain reaction (AP-PCR) by genotype monitoring. Unstimulated submandibular/sublingual secretions were collected and the concentrations of secretory IgA were determined by the enzyme-linked immunosorbent assay (ELISA). Each saliva sample was examined by Western blot to analyze the immunoreactivity of naturally occurring salivary secretory IgA antibodies for his/her own indigenous strain, spouse’s strain and reference strains including S. mutans GS-5 and Ingbritt (C). Results The results showed that naturally induced salivary IgA antibodies against S. mutans were present in all subjects. Almost all subjects had the similar individual immunoblotting profiles to different genotype strains. Conclusions The current study indicated that the immunoreactivity of secretory IgA might have no direct correlation with the colonization of indigenous flora and rejection of exogenous strains in adults. The relationship of microbes, host and dental caries should be in the light of coevolved microecosystem as a whole, but not caused by one factor alone. PMID:27303613

  1. Intake of indigestible carbohydrates influences IgA response and polymeric Ig receptor expression in the rat submandibular gland.

    PubMed

    Yamamoto, Yuko; To, Masahiro; Hayashi, Takashi; Shimizu, Tomoko; Kamata, Yohei; Saruta, Juri; Takahashi, Toru; Tsukinoki, Keiichi

    2015-06-28

    Secretory IgA in the saliva is essential for protection from mucosally transmitted pathogens and maintaining homeostasis at mucosal surfaces of the oral cavity. Expression of submandibular gland polymeric Ig receptor (pIgR) is essential for IgA secretion. In the present study, we investigated the influence of indigestible carbohydrates on IgA production in the salivary gland and saliva. Five-week-old rats were fed a fibre-free diet (control), or a diet with 5 % (w/w) fructo-oligosaccharide (FOS) or a combination of 2·5 % (w/w) polydextrose (PDX) and 2·5 % (w/w) lactitol for 21-d. IgA concentrations in the caecal digesta, submandibular gland tissue, and saliva in the FOS and PDX+lactitol diet groups were significantly higher than those in the control group (P< 0·05). The increase in IgA in the submandibular gland tissue was confirmed using immunohistochemical analysis. However, the IgA concentrations of serum did not differ between the FOS or PDX+lactitol groups and the control group (P= 0·5). In the FOS and PDX+lactitol groups, the pIgR mRNA (pIgR/β-actin) expression level in the submandibular gland tissue was significantly higher than that in the control group (P< 0·05). The present study suggests that indigestible carbohydrates play an important role in the increase in IgA concentrations in the submandibular gland tissue, saliva, and caecal digesta.

  2. Different secretory IgA antibody responses after immunization with inactivated and live poliovirus vaccines.

    PubMed

    Hanson, L A; Carlsson, B; Jalil, F; Lindblad, B S; Khan, S R; van Wezel, A L

    1984-01-01

    The influence on secretory IgA antibody levels in milk and saliva of vaccination with oral, live poliovirus vaccine ( OPV ) and inactivated poliovirus vaccine (IPV) was studied. IPV, especially the antigen-rich Dutch vaccine, more often induced increases in antibody titers in milk (50%) than did OPV (26%) (P less than .01). OPV more often decreased the antibody levels in milk (40%) than did IPV (10%) (P less than .01). It was striking that mainly high prevaccination titers were decreased. The increases of IgA antibody in saliva were less striking. IPV caused increases as often in milk as in saliva, whereas OPV more often induced increases in IgA antibody in saliva, but there was a poor correlation between the changes in antibody titers in milk and those in saliva.

  3. Evaluation of the relationship between passive smoking and salivary electrolytes, protein, secretory IgA, sialic acid and amylase in young children.

    PubMed

    Avşar, Aysun; Darka, Ozge; Bodrumlu, Ebru Hazar; Bek, Yüksel

    2009-05-01

    To evaluate the relationship between passive smoking as determined by salivary cotinine levels and salivary electrolytes, protein, secretory IgA, sialic acid and amylase in children. Saliva was collected from 90 passive smoker (PS) subjects (the study group) and 90 healthy age-matched children (the control group). The study group was divided into three subgroups according the number of cigarettes smoked. Socio-economic status, dental and dietary habits were recorded by questionnaire. Stimulated salivary calcium (Ca), phosphate (P), sodium (Na), potassium (P), total protein, amylase activity, sialic acid level, secretory IgA concentration and cotinine level were analysed. All data were analysed using SPSS, version 13.0. Socio-economic status, dental and dietary habits were similar between the two groups. The salivary electrolytes concentrations did not reveal significant difference between the two groups (p>0.05). The mean cotinine levels of PS children were 1.58+/-4.3 ng/mL. The salivary concentrations of protein were similar between the two groups (p>0.05). The salivary secretory IgA concentration was significantly lower in the PS group than controls. The sialic acid level and amylase activity in PS group were found significantly higher compared with the controls (p<0.05). No difference was observed for all these parameters with sex (p>0.05). When saliva samples were analysed for output, the sialic acid level and amylase activity increased significantly in PS subjects (p<0.05). Further, the output of secretory IgA concentration was found significantly lower compared with the controls (p<0.05). In conclusion, we show that passive smoking was associated with a decrease in secretory IgA concentration, whereas with increase in amylase activity and sialic acid level of stimulated whole saliva in young children.

  4. Estimating the incidence of rotavirus infection in children from India and Malawi from serial anti-rotavirus IgA titres.

    PubMed

    Bennett, Aisleen; Nagelkerke, Nico; Heinsbroek, Ellen; Premkumar, Prasanna S; Wnęk, Małgorzata; Kang, Gagandeep; French, Neil; Cunliffe, Nigel A; Bar-Zeev, Naor; Lopman, Ben; Iturriza-Gomara, Miren

    2017-01-01

    Accurate estimates of rotavirus incidence in infants are crucial given disparities in rotavirus vaccine effectiveness from low-income settings. Sero-surveys are a pragmatic means of estimating incidence however serological data is prone to misclassification. This study used mixture models to estimate incidence of rotavirus infection from anti-rotavirus immunoglobulin A (IgA) titres in infants from Vellore, India, and Karonga, Malawi. IgA titres were measured using serum samples collected at 6 month intervals for 36 months from 373 infants from Vellore and 12 months from 66 infants from Karonga. Mixture models (two component Gaussian mixture distributions) were fit to the difference in titres between time points to estimate risk of sero-positivity and derive incidence estimates. A peak incidence of 1.05(95% confidence interval [CI]: 0.64, 1.64) infections per child-year was observed in the first 6 months of life in Vellore. This declined incrementally with each subsequent time interval. Contrastingly in Karonga incidence was greatest in the second 6 months of life (1.41 infections per child year [95% CI: 0.79, 2.29]). This study demonstrates that infants from Vellore experience peak rotavirus incidence earlier than those from Karonga. Identifying such differences in transmission patterns is important in informing vaccine strategy, particularly where vaccine effectiveness is modest.

  5. C1 finite elements on non-tensor-product 2d and 3d manifolds

    PubMed Central

    Nguyen, Thien; Karčiauskas, Kęstutis; Peters, Jörg

    2015-01-01

    Geometrically continuous (Gk) constructions naturally yield families of finite elements for isogeometric analysis (IGA) that are Ck also for non-tensor-product layout. This paper describes and analyzes one such concrete C1 geometrically generalized IGA element (short: gIGA element) that generalizes bi-quadratic splines to quad meshes with irregularities. The new gIGA element is based on a recently-developed G1 surface construction that recommends itself by its a B-spline-like control net, low (least) polynomial degree, good shape properties and reproduction of quadratics at irregular (extraordinary) points. Remarkably, for Poisson’s equation on the disk using interior vertices of valence 3 and symmetric layout, we observe O(h3) convergence in the L∞ norm for this family of elements. Numerical experiments confirm the elements to be effective for solving the trivariate Poisson equation on the solid cylinder, deformations thereof (a turbine blade), modeling and computing geodesics on smooth free-form surfaces via the heat equation, for solving the biharmonic equation on the disk and for Koiter-type thin-shell analysis. PMID:26594070

  6. C1 finite elements on non-tensor-product 2d and 3d manifolds.

    PubMed

    Nguyen, Thien; Karčiauskas, Kęstutis; Peters, Jörg

    2016-01-01

    Geometrically continuous ( G k ) constructions naturally yield families of finite elements for isogeometric analysis (IGA) that are C k also for non-tensor-product layout. This paper describes and analyzes one such concrete C 1 geometrically generalized IGA element (short: gIGA element) that generalizes bi-quadratic splines to quad meshes with irregularities. The new gIGA element is based on a recently-developed G 1 surface construction that recommends itself by its a B-spline-like control net, low (least) polynomial degree, good shape properties and reproduction of quadratics at irregular (extraordinary) points. Remarkably, for Poisson's equation on the disk using interior vertices of valence 3 and symmetric layout, we observe O ( h 3 ) convergence in the L ∞ norm for this family of elements. Numerical experiments confirm the elements to be effective for solving the trivariate Poisson equation on the solid cylinder, deformations thereof (a turbine blade), modeling and computing geodesics on smooth free-form surfaces via the heat equation, for solving the biharmonic equation on the disk and for Koiter-type thin-shell analysis.

  7. Corticosteroid for IgA Nephropathy: Are They Really Therapeutic?

    PubMed

    Lin, Yujia; Jia, Junya; Guo, Yipeng; He, Dandan; Zhang, Yaru; Wang, Fuzhen; Yan, Tiekun; Liu, Youxia; Lin, Shan

    2018-06-06

    IgA nephropathy (IgAN) is a common chronic glomerular disease that, in most patients, slowly progresses to end-stage kidney disease. The therapy with corticosteroid in IgAN is still a worldwide problem that is confusing the clinicians. MEDLINE, EMBASE, the Cochrane Library, and article reference lists were searched for randomized controlled trials (RCTs) that compared corticosteroids with placebo and any other non-immunosuppressive agents in treating IgAN. Twelve RCTs involving 1,057 patients were included. Overall, we found that steroids had statistically significant effects in preventing the decline in renal function (relative risk 0.42, 95% CI 0.25-0.71, p < 0.001) and reducing proteinuria (SMD: -0.58 g/day, 95% CI -0.80 to -0.36 g/day) in patients with IgAN. The association between glucocorticoid and risk of kidney outcome was not modified by steroids' type (prednisone or methylprednisone), dose (≤30 or > 30 mg/day), duration (≤8 or > 8 months), or serum creatinine (< 1.10 or ≥1.10 mg/dL). But steroids increased the risk of side effects such as gastrointestinal and endocrinium symptoms. This study provides the clear beneficial effects of the steroids therapy on the kidney function and proteinuria, although it should be used with caution. © 2018 S. Karger AG, Basel.

  8. Mouse IgA inhibits cell growth by stimulating tumor necrosis factor-alpha production and apoptosis of macrophage cell lines.

    PubMed

    Reljic, Rajko; Crawford, Carol; Challacombe, Stephen; Ivanyi, Juraj

    2004-04-01

    Potent Fcalpha-mediated actions of IgA have previously been shown for myeloid cells from man, but much less is known in relation to murine cells. Here, we report that mouse monoclonal IgA, irrespective of their antigenic specificity, inhibit the proliferation of mouse macrophage cell lines. The anti-proliferative activity was manifested by both monomeric and polymeric mouse IgA, but not by mouse monoclonal IgG and IgM. Growth of J774 cells was significantly inhibited during the 4-8 days of logarithmic growth, followed by a subsequent recovery of cell numbers prior to the stationary phase. We demonstrated that IgA binds to J774 cells, stimulates tumor necrosis factor (TNF)-alpha production and induces apoptosis which is not dependent on NO or FAS/CD95. We also demonstrated that IgA, in synergy with IFN-gamma, induced TNF-alpha production and apoptosis of thioglycollate-elicited mouse peritoneal macrophages. Thus, the in vitro actions of IgA described may also play a regulatory role for mouse macrophages in vivo.

  9. Impaired airway mucociliary function reduces antigen-specific IgA immune response to immunization with a claudin-4-targeting nasal vaccine in mice.

    PubMed

    Suzuki, Hidehiko; Nagatake, Takahiro; Nasu, Ayaka; Lan, Huangwenxian; Ikegami, Koji; Setou, Mitsutoshi; Hamazaki, Yoko; Kiyono, Hiroshi; Yagi, Kiyohito; Kondoh, Masuo; Kunisawa, Jun

    2018-02-13

    Vaccine delivery is an essential element for the development of mucosal vaccine, but it remains to be investigated how physical barriers such as mucus and cilia affect vaccine delivery efficacy. Previously, we reported that C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) targeted claudin-4, which is expressed by the epithelium associated with nasopharynx-associated lymphoid tissue (NALT), and could be effective as a nasal vaccine delivery. Mice lacking tubulin tyrosine ligase-like family, member 1 (Ttll1-KO mice) showed mucus accumulation in nasal cavity due to the impaired motility of respiratory cilia. Ttll1-KO mice nasally immunized with C-CPE fused to pneumococcal surface protein A (PspA-C-CPE) showed reduced PspA-specific nasal IgA responses, impaired germinal center formation, and decreased germinal center B-cells and follicular helper T cells in the NALT. Although there was no change in the expression of claudin-4 in the NALT epithelium in Ttll1-KO mice, the epithelium was covered by a dense mucus that prevented the binding of PspA-C-CPE to NALT. However, administration of expectorant N-acetylcysteine removed the mucus and rescued the PspA-specific nasal IgA response. These results show that the accumulation of mucus caused by impaired respiratory cilia function is an interfering factor in the C-CPE-based claudin-4-targeting nasal vaccine.

  10. Optimized catalytic DNA-cleaving ribozymes

    NASA Technical Reports Server (NTRS)

    Joyce, Gerald F. (Inventor)

    1996-01-01

    The present invention discloses nucleic acid enzymes capable of cleaving nucleic acid molecules, including single-stranded DNA, in a site-specific manner under physiologic conditions, as well as compositions including same. The present invention also discloses methods of making and using the disclosed enzymes and compositions.

  11. Delta ribozyme has the ability to cleave in transan mRNA.

    PubMed Central

    Roy, G; Ananvoranich, S; Perreault, J P

    1999-01-01

    We report here the first demonstration of the cleavage of an mRNA in trans by delta ribozyme derived from the antigenomic version of the human hepatitis delta virus (HDV). We characterized potential delta ribozyme cleavage sites within HDV mRNA sequence (i.e. C/UGN6), using oligonucleotide binding shift assays and ribonuclease H hydrolysis. Ribozymes were synthesized based on the structural data and then tested for their ability to cleave the mRNA. Of the nine ribozymes examined, three specifically cleaved a derivative HDV mRNA. All three active ribozymes gave consistent indications that they cleaved single-stranded regions. Kinetic characterization of the ability of ribozymes to cleave both the full-length mRNA and either wild-type or mutant small model substrate suggests: (i) delta ribozyme has turnovers, that is to say, several mRNA molecules can be successively cleaved by one ribozyme molecule; and (ii) the substrate specificity of delta ribozyme cleavage is not restricted to C/UGN6. Specifically, substrates with a higher guanosine residue content upstream of the cleavage site (i.e. positions -4 to -2) were always cleaved more efficiently than wild-type substrate. This work shows that delta ribozyme constitutes a potential catalytic RNA for further gene-inactivation therapy. PMID:9927724

  12. 1,25-dihydroxyvitamin D3 induces CCR10 expression in terminally differentiating human B cells.

    PubMed

    Shirakawa, Aiko-Konno; Nagakubo, Daisuke; Hieshima, Kunio; Nakayama, Takashi; Jin, Zhe; Yoshie, Osamu

    2008-03-01

    In the B cell lineage, CCR10 is known to be selectively expressed by plasma cells, especially those secreting IgA. In this study, we examined the regulation of CCR10 expression in terminally differentiating human B cells. As reported previously, IL-21 efficiently induced the differentiation of activated human CD19+ B cells into IgD-CD38+ plasma cells in vitro. A minor proportion of the resulting CD19+IgD-CD38+ cells expressed CCR10 at low levels. 1,25-Dihydroxyvitamin D3 (1,25-(OH)2D3), the active metabolite of vitamine D3, dramatically increased the proportion of CD19+IgD-CD38+ cells expressing high levels of CCR10. The 1,25-(OH)2D3 also increased the number of CCR10+ cells expressing surface IgA, although the majority of CCR10+ cells remained negative for surface IgA. Thus, 1,25-(OH)2D3 alone may not be sufficient for the induction of IgA expression in terminally differentiating human B cells. To further determine whether 1,25-(OH)2D3 directly induces CCR10 expression in terminally differentiating B cells, we next performed the analysis on the human CCR10 promoter. We identified a proximal Ets-1 site and an upstream potential vitamin D response element to be critical for the inducible expression of CCR10 by 1,25-(OH)2D3. We confirmed the specific binding of Ets-1 and 1,25-(OH)2D3-activated vitamin D receptor to the respective sites. In conclusion, 1,25-(OH)2D3 efficiently induces CCR10 expression in terminally differentiating human B cells in vitro. Furthermore, the human CCR10 promoter is cooperatively activated by Ets-1 and vitamin D receptor in the presence of 1,25-(OH)2D3.

  13. Antigen-specific IgA B memory cell responses to Shigella antigens elicited in volunteers immunized with live attenuated Shigella flexneri 2a oral vaccine candidates

    PubMed Central

    Simon, J. K.; Maciel, M.; Weld, E.D.; Wahid, R.; Pasetti, M.F.; Picking, W.L.; Kotloff, K. L.; Levine, M. M.; Sztein, M. B.

    2011-01-01

    We studied the induction of antigen-specific IgA memory B cells (BM) in volunteers who received live attenuated Shigella flexneri 2a vaccines. Subjects ingested a single oral dose of 107, 108 or 109 CFU of S. flexneri 2a with deletions in guaBA (CVD 1204) or in guaBA, set and sen (CVD 1208). Antigen-specific serum and stool antibody responses to LPS and Ipa B were measured on days 0, 7, 14, 28 and 42. IgA BM cells specific to LPS, Ipa B and total IgA were assessed on days 0 and 28. We show the induction of significant LPS-specific IgA BM cells in anti-LPS IgA seroresponders. Positive correlations were found between anti-LPS IgA BM cells and anti-LPS IgA in serum and stool; IgA BM cell responses to IpaB were also observed. These BM cell responses are likely play an important role in modulating the magnitude and longevity of the humoral response. PMID:21388888

  14. Dietary zinc is a key environmental modifier in the progression of IgA nephropathy.

    PubMed

    Maiguma, Masayuki; Suzuki, Yusuke; Suzuki, Hitoshi; Okazaki, Keiko; Aizawa, Masashi; Muto, Masahiro; Tomino, Yasuhiko

    2014-01-01

    IgA nephropathy (IgAN) shows diverse epidemiological characteristics, resulting from both genetic and acquired (e.g., environmental) causes. Environmental factors, such as diet or exposure to exogenous antigens, may prescribe the progression or prognosis of IgAN. It remains unclear as to how diet and infection influence susceptibility to IgAN. A relationship, such as Toll-like receptors (TLRs), especially TLR9 and TLR4, was demonstrated between IgAN and pathogen-recognition molecules. Recently, zinc (Zn) was discovered to be involved in various immune-related diseases, affecting B, T, and dendritic cells (DCs). This study investigates the relationship between dietary Zn and IgAN development in IgAN-prone mice. Seven-week-old IgAN-prone mice were divided into low, normal, and high Zn diet groups. To assess exogenous pathogen-mediated immune responses, lipopolysaccharide (LPS) was nasally administered. The activity of IgAN was biochemically and pathologically evaluated during the disease course. We also examined in vitro IgA production in spleen cells or in combinations of cocultured B, T, and DCs under various Zn conditions with or without LPS. Dietary conditioning with Zn affected serum immunoglobulins and urinary albumin levels, and mesangial deposition of IgA and IgG. Zn deficiency is associated with IgAN progression through the activation of the TLR4/TIR-domain-containing adapter-inducing interferon-β (TRIF), but not the TLR9, in DCs. Zn supplementation prevented disease aggravation. Our findings indicate that immune conditioning with dietary Zn alters nephritogenic IgA production after mucosal infection.

  15. Synthesis of Tetraphenylstannacyclopentadienes (Stannoles). II. Derivatives and Adducts of 1,1-Dihalo-2,3,4,5-tetraphenylstannoles.

    DTIC Science & Technology

    1981-04-15

    products (4-bromo-l,2,3,4-tetraphenylbutadienyl)tin tribromide o (4-iodo-l,2,3,4-tetraphenylbutadienyl)tin triiodide. Even gentle chlorination of...hexaphenyistannole by elemental chlorine cleaves the ring tin-carbon bonds to form cis-cis-l ,4-dichloro-l ,2 ,3 ,4-tetraphenylbutadiene-l, 3 and diphenyltin... chlorination of hexaphenylstannole by elemental chlorine cleaves the ring tin-carbon bonds to form cis- cis-l,4-dichloro-l,2,3,4-tetraphenylbutadiene-1,3

  16. Low α-defensin gene copy number increases the risk for IgA nephropathy and renal dysfunction.

    PubMed

    Ai, Zhen; Li, Ming; Liu, Wenting; Foo, Jia-Nee; Mansouri, Omniah; Yin, Peiran; Zhou, Qian; Tang, Xueqing; Dong, Xiuqing; Feng, Shaozhen; Xu, Ricong; Zhong, Zhong; Chen, Jian; Wan, Jianxin; Lou, Tanqi; Yu, Jianwen; Zhou, Qin; Fan, Jinjin; Mao, Haiping; Gale, Daniel; Barratt, Jonathan; Armour, John A L; Liu, Jianjun; Yu, Xueqing

    2016-06-29

    Although a major source of genetic variation, copy number variations (CNVs) and their involvement in disease development have not been well studied. Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. We performed association analysis of the DEFA1A3 CNV locus in two independent IgAN cohorts of southern Chinese Han (total of 1189 cases and 1187 controls). We discovered three independent copy number associations within the locus: DEFA1A3 [P = 3.99 × 10(-9); odds ratio (OR), 0.88], DEFA3 (P = 6.55 × 10(-5); OR, 0.82), and a noncoding deletion variant (211bp) (P = 3.50 × 10(-16); OR, 0.75) (OR per copy, fixed-effects meta-analysis). While showing strong association with an increased risk for IgAN (P = 9.56 × 10(-20)), low total copy numbers of the three variants also showed significant association with renal dysfunction in patients with IgAN (P = 0.03; hazards ratio, 3.69; after controlling for the effects of known prognostic factors) and also with increased serum IgA1 (P = 0.02) and galactose-deficient IgA1 (P = 0.03). For replication, we confirmed the associations of DEFA1A3 (P = 4.42 × 10(-4); OR, 0.82) and DEFA3 copy numbers (P = 4.30 × 10(-3); OR, 0.74) with IgAN in a Caucasian cohort (531 cases and 198 controls) and found the 211bp variant to be much rarer in Caucasians. We also observed an association of the 211bp copy number with membranous nephropathy (P = 1.11 × 10(-7); OR, 0.74; in 493 Chinese cases and 500 matched controls), but not with diabetic kidney disease (in 806 Chinese cases and 786 matched controls). By explaining 4.96% of disease risk and influencing renal dysfunction in patients with IgAN, the DEFA1A3 CNV locus may be a potential therapeutic target for developing treatments for this disease. Copyright © 2016, American Association for the Advancement of Science.

  17. Cleavage strongly influences whether soluble HIV-1 envelope glycoprotein trimers adopt a native-like conformation

    PubMed Central

    Ringe, Rajesh P.; Sanders, Rogier W.; Yasmeen, Anila; Kim, Helen J.; Lee, Jeong Hyun; Cupo, Albert; Korzun, Jacob; Derking, Ronald; van Montfort, Thijs; Julien, Jean-Philippe; Wilson, Ian A.; Klasse, Per Johan; Ward, Andrew B.; Moore, John P.

    2013-01-01

    We compare the antigenicity and conformation of soluble, cleaved vs. uncleaved envelope glycoprotein (Env gp)140 trimers from the subtype A HIV type 1 (HIV-1) strain BG505. The impact of gp120–gp41 cleavage on trimer structure, in the presence or absence of trimer-stabilizing modifications (i.e., a gp120–gp41 disulfide bond and an I559P gp41 change, together designated SOSIP), was assessed. Without SOSIP changes, cleaved trimers disintegrate into their gp120 and gp41-ectodomain (gp41ECTO) components; when only the disulfide bond is present, they dissociate into gp140 monomers. Uncleaved gp140s remain trimeric whether SOSIP substitutions are present or not. However, negative-stain electron microscopy reveals that only cleaved trimers form homogeneous structures resembling native Env spikes on virus particles. In contrast, uncleaved trimers are highly heterogeneous, adopting a variety of irregular shapes, many of which appear to be gp120 subunits dangling from a central core that is presumably a trimeric form of gp41ECTO. Antigenicity studies with neutralizing and nonneutralizing antibodies are consistent with the EM images; cleaved, SOSIP-stabilized trimers express quaternary structure-dependent epitopes, whereas uncleaved trimers expose nonneutralizing gp120 and gp41ECTO epitopes that are occluded on cleaved trimers. These findings have adverse implications for using soluble, uncleaved trimers for structural studies, and the rationale for testing uncleaved trimers as vaccine candidates also needs to be reevaluated. PMID:24145402

  18. Melphalan-induced apoptosis in multiple myeloma cells is associated with a cleavage of Mcl-1 and Bim and a decrease in the Mcl-1/Bim complex.

    PubMed

    Gomez-Bougie, Patricia; Oliver, Lisa; Le Gouill, Steven; Bataille, Régis; Amiot, Martine

    2005-12-01

    Multiple myeloma (MM) is a rapidly fatal plasma-cell malignancy that evolves mainly in the bone marrow. Melphalan is widely used to treat patients with MM but as yet its mechanisms of action are poorly documented. In the current study, we demonstrate that melphalan induces a drastic downregulation of Mcl-1L, Bcl-x(L) and BimEL in human melphalan-sensitive myeloma cells while the most potent proapoptotic isoforms, BimL and S, are affected to a lesser extent. Moreover, Mcl-1L and BimEL disappearance is associated with the generation of proapoptotic cleaved forms generated by a caspase cleavage. In myeloma cells, we have previously shown that Mcl-1 neutralizes the proapoptotic function of Bim and therefore, prevents the activation of death effectors. In this study, we demonstrate that melphalan disrupts the Mcl-1/Bim complex whereas the Bcl-2/Bim complex is not modified. The disappearance of full length Mcl-1 allows the release of Bim isoforms, particularly L and S, which can exert their proapoptotic function and leads to Bax activation and cytochrome c release. Thus, we can hypothesize that the cleaved 26 kDa proapoptotic Mcl-1 and the 19 and 12 kDa of Bim, generated during melphalan treatment could contribute to the amplification loop of apoptosis.

  19. Baker's yeast beta glucan supplementation increases salivary IgA and decreases cold/flu symptomatic days after intense exercise.

    PubMed

    McFarlin, Brian K; Carpenter, Katie C; Davidson, Tiffany; McFarlin, Meredith A

    2013-09-01

    Strenuous exercise, such as running a marathon, is known to suppress mucosal immunity for up to 24 hr, which can increase the risk of developing an upper respiratory tract infection (URTI) and reduced performance capacity (Allgrove JE, Geneen L, Latif S, Gleeson M. Influence of a fed or fasted state on the s-IgA response to prolonged cycling in active men and women. Int J Sport Nutr Exerc Metab. 2009;19(3):209-221; Barrett B, Locken K, Maberry R, Schwamman J, Brown R, Bobula J, Stauffacher EA. The Wisconsin Upper Respiratory Symptom Survey (WURSS): a new research instrument for assessing the common cold. J Fam Pract. 2002;51(3):265; Carpenter KC, Breslin WL, Davidson T, Adams A, McFarlin BK. Baker's yeast beta glucan supplementation increases monocytes and cytokines post-exercise: implications for infection risk? Br J Nutr. 2012;1-9). While many dietary interventions have been used to combat postexercise immune suppression, most have been ineffective. The key purpose of this study was to determine if baker's yeast β-glucan (BG) could positively affect the immune system of individuals undergoing intense exercise stress using two experiments. In the first (E1; N = 182 men and women), BG was compared to placebo supplementation for the incidence of URTI symptoms for 28 days postmarathon. In the second (E2; N = 60 men and women) changes in salivary immunoglobulin A (IgA) were evaluated after 50-min of strenuous cycling when participants had been supplemented for 10 days with either BG (250 mg/day) or placebo (rice flour). For E1, subjects reported URTI symptoms using a daily health log. For E2, saliva was collected prior to, immediately, and 2-hr postexercise using a salivette. Data for E1 and E2 were analyzed using separate analyses of variance (ANOVAs) with repeated measures (p < .05). In E1, BG was associated with a 37% reduction in the number of cold/flu symptom days postmarathon compared to placebo (p = .026). In E2, BG was associated with a 32% increase in

  20. Baker's Yeast Beta Glucan Supplementation Increases Salivary IgA and Decreases Cold/Flu Symptomatic Days After Intense Exercise

    PubMed Central

    McFarlin, Brian K.; Carpenter, Katie C.; Davidson, Tiffany; McFarlin, Meredith A.

    2013-01-01

    ABSTRACT Strenuous exercise, such as running a marathon, is known to suppress mucosal immunity for up to 24 hr, which can increase the risk of developing an upper respiratory tract infection (URTI) and reduced performance capacity (Allgrove JE, Geneen L, Latif S, Gleeson M. Influence of a fed or fasted state on the s-IgA response to prolonged cycling in active men and women. Int J Sport Nutr Exerc Metab. 2009;19(3):209–221; Barrett B, Locken K, Maberry R, Schwamman J, Brown R, Bobula J, Stauffacher EA. The Wisconsin Upper Respiratory Symptom Survey (WURSS): a new research instrument for assessing the common cold. J Fam Pract. 2002;51(3):265; Carpenter KC, Breslin WL, Davidson T, Adams A, McFarlin BK. Baker's yeast beta glucan supplementation increases monocytes and cytokines post-exercise: implications for infection risk? Br J Nutr. 2012;1–9). While many dietary interventions have been used to combat postexercise immune suppression, most have been ineffective. The key purpose of this study was to determine if baker's yeast β-glucan (BG) could positively affect the immune system of individuals undergoing intense exercise stress using two experiments. In the first (E1; N = 182 men and women), BG was compared to placebo supplementation for the incidence of URTI symptoms for 28 days postmarathon. In the second (E2; N = 60 men and women) changes in salivary immunoglobulin A (IgA) were evaluated after 50-min of strenuous cycling when participants had been supplemented for 10 days with either BG (250 mg/day) or placebo (rice flour). For E1, subjects reported URTI symptoms using a daily health log. For E2, saliva was collected prior to, immediately, and 2-hr postexercise using a salivette. Data for E1 and E2 were analyzed using separate analyses of variance (ANOVAs) with repeated measures (p < .05). In E1, BG was associated with a 37% reduction in the number of cold/flu symptom days postmarathon compared to placebo (p = .026). In E2, BG was associated with a 32

  1. Previously misdiagnosed linear IgA dermatosis resolved with dapsone.

    PubMed

    Tieppo Francio, Vinicius; Towery, Chris; Davani, Saeid; Allen, Travis; Brown, Tony L

    2018-04-25

    This is the case of a 25-year-old African American woman with a 3-week history of itching with burning, blistering lesions on her torso and extremities. Medical history was unremarkable. Medical treatments included three visits to urgent care, where she was treated with antivirals, oral and topical steroids, antibiotics and antifungals unsuccessfully. We performed a skin biopsy, and immunoflorescent studies revealed a linear deposition of IgA antigen at the basement membrane. The clinical diagnosis of linear IgA dermatosis (LAD) was established, with no eliciting cause, other than potential occupational exposure to Chlamydophila psittaci via her employment in a pet store. This is the first case to our knowledge to report such an association. However, confirmation of the exposure would only establish correlation, not causality. Resolution of symptoms and blisters was achieved with dapsone treatment. Accordingly, we highlight the crucial importance of reviewing exposures, along with the potential aetiology of LAD. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  2. Specialization of the DNA-Cleaving Activity of a Group I Ribozyme Through In Vitro Evolution

    NASA Technical Reports Server (NTRS)

    Tsang, Joyce; Joyce, Gerald F.

    1996-01-01

    In an earlier study, an in vitro evolution procedure was applied to a large population of variants of the Tetrahymena group 1 ribozyme to obtain individuals with a 10(exp 5)-fold improved ability to cleave a target single-stranded DNA substrate under simulated physiological conditions. The evolved ribozymes also showed a twofold improvement, compared to the wild-type, in their ability to cleave a single-stranded RNA substrate. Here, we report continuation of the in vitro evolution process using a new selection strategy to achieve both enhanced DNA and diminished RNA-cleavage activity. Our strategy combines a positive selection for DNA cleavage with a negative selection against RNA binding. After 36 "generations" of in vitro evolution, the evolved population showed an approx. 100-fold increase in the ratio of DNA to RNA-cleavage activity. Site-directed mutagenesis experiment confirmed the selective advantage of two covarying mutations within the catalytic core of ribozyme that are largely responsible for this modified behavior. The population of ribozymes has now undergone a total of 63 successive generations of evolution, resulting in an average 28 mutations relative to the wild-type that are responsible for the altered phenotype.

  3. MicroRNA-339-5p down-regulates protein expression of β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) in human primary brain cultures and is reduced in brain tissue specimens of Alzheimer disease subjects.

    PubMed

    Long, Justin M; Ray, Balmiki; Lahiri, Debomoy K

    2014-02-21

    Alzheimer disease (AD) results, in part, from the excess accumulation of the amyloid-β (Aβ) peptide as neuritic plaques in the brain. The short Aβ peptide is derived from the large transmembrane Aβ precursor protein (APP). The rate-limiting step in the production of Aβ from APP is mediated by the β-site APP-cleaving enzyme 1 (BACE1). Dysregulation of BACE1 levels leading to excess Aβ deposition is implicated in sporadic AD. Thus, elucidating the full complement of regulatory pathways that control BACE1 expression is key to identifying novel drug targets central to the Aβ-generating process. MicroRNAs (miRNAs) are expected to participate in this molecular network. Here, we identified a known miRNA, miR-339-5p, as a key contributor to this regulatory network. Two distinct miR-339-5p target sites were predicted in the BACE1 3'-UTR by in silico analyses. Co-transfection of miR-339-5p with a BACE1 3'-UTR reporter construct resulted in significant reduction in reporter expression. Mutation of both target sites eliminated this effect. Delivery of the miR-339-5p mimic also significantly inhibited expression of BACE1 protein in human glioblastoma cells and human primary brain cultures. Delivery of target protectors designed against the miR-339-5p BACE1 3'-UTR target sites in primary human brain cultures significantly elevated BACE1 expression. Finally, miR-339-5p levels were found to be significantly reduced in brain specimens isolated from AD patients as compared with age-matched controls. Therefore, miR-339-5p regulates BACE1 expression in human brain cells and is most likely dysregulated in at least a subset of AD patients making this miRNA a novel drug target.

  4. MicroRNA-339-5p Down-regulates Protein Expression of β-Site Amyloid Precursor Protein-Cleaving Enzyme 1 (BACE1) in Human Primary Brain Cultures and Is Reduced in Brain Tissue Specimens of Alzheimer Disease Subjects*

    PubMed Central

    Long, Justin M.; Ray, Balmiki; Lahiri, Debomoy K.

    2014-01-01

    Alzheimer disease (AD) results, in part, from the excess accumulation of the amyloid-β (Aβ) peptide as neuritic plaques in the brain. The short Aβ peptide is derived from the large transmembrane Aβ precursor protein (APP). The rate-limiting step in the production of Aβ from APP is mediated by the β-site APP-cleaving enzyme 1 (BACE1). Dysregulation of BACE1 levels leading to excess Aβ deposition is implicated in sporadic AD. Thus, elucidating the full complement of regulatory pathways that control BACE1 expression is key to identifying novel drug targets central to the Aβ-generating process. MicroRNAs (miRNAs) are expected to participate in this molecular network. Here, we identified a known miRNA, miR-339-5p, as a key contributor to this regulatory network. Two distinct miR-339-5p target sites were predicted in the BACE1 3′-UTR by in silico analyses. Co-transfection of miR-339-5p with a BACE1 3′-UTR reporter construct resulted in significant reduction in reporter expression. Mutation of both target sites eliminated this effect. Delivery of the miR-339-5p mimic also significantly inhibited expression of BACE1 protein in human glioblastoma cells and human primary brain cultures. Delivery of target protectors designed against the miR-339-5p BACE1 3′-UTR target sites in primary human brain cultures significantly elevated BACE1 expression. Finally, miR-339-5p levels were found to be significantly reduced in brain specimens isolated from AD patients as compared with age-matched controls. Therefore, miR-339-5p regulates BACE1 expression in human brain cells and is most likely dysregulated in at least a subset of AD patients making this miRNA a novel drug target. PMID:24352696

  5. Lymphotoxin Alpha-Deficient Mice Clear Persistent Rotavirus Infection after Local Generation of Mucosal IgA

    PubMed Central

    Lopatin, Uri; Blutt, Sarah E.; Conner, Margaret E.

    2013-01-01

    Rotavirus is a major cause of pediatric diarrheal illness worldwide. To explore the role of organized intestinal lymphoid tissues in infection by and immunity to rotavirus, lymphotoxin alpha-deficient (LTα−/−) mice that lack Peyer's patches and mesenteric lymph nodes were orally infected with murine rotavirus. Systemic rotavirus was cleared within 10 days in both LTα−/− and wild-type mice, and both strains developed early and sustained serum antirotavirus antibody responses. However, unlike wild-type mice, which resolved the intestinal infection within 10 days, LTα−/− mice shed fecal virus for approximately 50 days after inoculation. The resolution of fecal virus shedding occurred concurrently with induction of intestinal rotavirus-specific IgA in both mouse strains. Induction of intestinal rotavirus-specific IgA in LTα−/− mice correlated with the (late) appearance of IgA-producing plasma cells in the small intestine. This, together with the absence of rotavirus-specific serum IgA, implies that secretory rotavirus-specific IgA was produced locally. These findings indicate that serum IgG responses are insufficient and imply that local intestinal IgA responses are important for the clearance of rotavirus from intestinal tissues. Furthermore, they show that while LTα-dependent lymphoid tissues are important for the generation of IgA-producing B cells in the intestine, they are not absolutely required in the setting of rotavirus infection. Moreover, the induction of local IgA-producing B cell responses can occur late after infection and in an LTα-independent manner. PMID:23097456

  6. Evaluation of nasal IgA secretion in normal subjects by nasal spray and aspiration.

    PubMed

    Fujimoto, Chisa; Kido, Hiroshi; Sawabuchi, Takako; Mizuno, Dai; Hayama, Masaki; Yanagawa, Hiroaki; Takeda, Noriaki

    2009-06-01

    Nasal washing (NW) is a popular method for collecting human nasal lavage fluid. However, for NW the subject must be trained, and the method is unsuitable for field studies on untrained subjects. To overcome this problem, we have developed an easy and painless method, a nasal spray and aspiration (NSA) method. This method is different from NW in that the nasal cavity is misted over with saline, and the nasal lavage fluid is aspirated from the nostrils through a silicon tube. First, nasal lavage fluid was obtained twice by NSA with an interval of a week between lavages to evaluate intraindividual variability, and the IgA and protein levels in the nasal lavage fluid were measured by enzyme-linked immunosorbent assay and bicinchoninic acid assay, respectively. Next, the IgA value determined by NSA was compared with that by NW in another 12 normal subjects 2 days after NSA. In 10 normal subjects, mean volume of saline sprayed into the nose was 0.46+/-0.15 ml (mean+/-S.D.). Mean volume of aspirated nasal lavage fluid containing both sprayed saline and nasal secretion was 0.44+/-0.37 ml. The mean IgA level/mg protein in the nasal lavage fluid determined by NSA was 112+/-18 microg/mg protein at the first and 99+/-20 at the second times of measurement, being highly reproducible. The mean value by NSA was 114+/-19 microg/mg protein, being almost the same as that by NW of 99+/-27. These findings suggest that the IgA level/mg protein in nasal lavage fluid determined by NSA instead of NW might be useful for assessing the variability of nasal IgA secretion.

  7. Intestinal IgA responses to Giardia muris in mice depleted of helper T lymphocytes and in immunocompetent mice.

    PubMed

    Heyworth, M F

    1989-04-01

    Immunocompetent mice infected with Giardia muris generate an intestinal antibody response to this parasite and clear G. muris infection. Previous work has shown that G. muris infection is prolonged in mice that have been depleted of helper (CD4+) T lymphocytes by treatment with a monoclonal antibody (mAb) directed against the murine CD4 antigen. The aim of the present study was to compare the intestinal anti-Giardia antibody response in immunocompetent mice and in mice depleted of helper T (Th) lymphocytes by treatment with anti-CD4 mAb. Immunocompetent mice generated an IgA response to G. muris, as judged by the presence of IgA on Giardia trophozoites harvested from the intestine of these animals more than 10 days after the start of the infection. The anti-Giardia IgA response was impaired in mice depleted of Th lymphocytes, as judged by virtual absence of immunofluorescent staining of trophozoites from these animals for surface-bound IgA. Clearance of G. muris infection was impaired by treatment of mice with anti-CD4 mAb. The results suggest that Th (CD4+) lymphocytes are important for the generation of a local IgA response against G. muris trophozoites in the mouse intestine and that IgA anti-trophozoite antibody may contribute to the clearance of G. muris from the intestine of immunocompetent mice.

  8. RNA-Cleaving DNA Enzymes with Altered Regio- or Enantioselectivity

    NASA Technical Reports Server (NTRS)

    Ordoukhanian, Phillip; Joyce, Gerald F.

    2002-01-01

    In vitro evolution methods were used to obtain DNA enzymes that cleave either a 2',5' - phosphodiester following a wibonucleotide or a 3',5' -phosphodiester following an L-ribonucleotide. Both enzymes can operate in an intermolecular reaction format with multiple turnover. The DNA enzyme that cleaves a 2',5' -phosphodiester exhibits a k(sub cat) of approx. 0.01/ min and catalytic efficiency, k(sub cat)/k(sub m) of approx. 10(exp 5)/ M min. The enzyme that cleaves an L-ribonudeotide is about 10-fold slower and has a catalytic efficiency of approx. 4 x 10(exp 5)/ M min. Both enzymes require a divalent metal cation for their activity and have optimal catalytic rate at pH 7-8 and 35-50 C. In a comparison of each enzyme s activity with either its corresponding substrate that contains an unnatural ribonudeotide or a substrate that instead contains a standard ribonucleotide, the 2',5' -phosphodiester-deaving DNA enzyme exhibited a regioselectivity of 6000- fold, while the L-ribonucleotide-cleaving DNA enzyme exhibited an enantioselectivity of 50-fold. These molecules demonstrate how in vitro evolution can be used to obtain regio- and enantioselective catalysts that exhibit specificities for nonnatural analogues of biological compounds.

  9. Generation of recombinant pandemic H1N1 influenza virus with the HA cleavable by bromelain and identification of the residues influencing HA bromelain cleavage.

    PubMed

    Wang, Weijia; Suguitan, Amorsolo L; Zengel, James; Chen, Zhongying; Jin, Hong

    2012-01-20

    The proteolytic enzyme bromelain has been traditionally used to cleave the hemagglutinin (HA) protein at the C-terminus of the HA2 region to release the HA proteins from influenza virions. The bromelain cleaved HA (BHA) has been routinely used as an antigen to generate antiserum that is essential for influenza vaccine product release. The HA of the 2009 pandemic H1N1 influenza A/California/7/2009 (CA09) virus could not be cleaved efficiently by bromelain. To ensure timely delivery of BHA for antiserum production, we generated a chimeric virus that contained the HA1 region from CA09 and the HA2 region from the seasonal H1N1 A/South Dakota/6/2007 (SD07) virus that is cleavable by bromelain. The BHA from this chimeric virus was antigenically identical to CA09 and induced high levels of HA-specific antibodies and protected ferrets from wild-type H1N1 CA09 virus challenge. To determine the molecular basis of inefficient cleavage of CA09 HA by bromelain, the amino acids that differed between the HA2 of CA09 and SD07 were introduced into recombinant CA09 virus to assess their effect on bromelain cleavage. The D373N or E374G substitution in the HA2 stalk region of CA09 HA enabled efficient cleavage of CA09 HA by bromelain. Sequence analysis of the pandemic H1N1-like viruses isolated from 2010 revealed emergence of the E374K change. We found that K374 enabled the HA to be cleaved by bromelain and confirmed that the 374 residue is critical for HA bromelain cleavage. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Caspase-11 cleaves gasdermin D for non-canonical inflammasome signalling.

    PubMed

    Kayagaki, Nobuhiko; Stowe, Irma B; Lee, Bettina L; O'Rourke, Karen; Anderson, Keith; Warming, Søren; Cuellar, Trinna; Haley, Benjamin; Roose-Girma, Merone; Phung, Qui T; Liu, Peter S; Lill, Jennie R; Li, Hong; Wu, Jiansheng; Kummerfeld, Sarah; Zhang, Juan; Lee, Wyne P; Snipas, Scott J; Salvesen, Guy S; Morris, Lucy X; Fitzgerald, Linda; Zhang, Yafei; Bertram, Edward M; Goodnow, Christopher C; Dixit, Vishva M

    2015-10-29

    Intracellular lipopolysaccharide from Gram-negative bacteria including Escherichia coli, Salmonella typhimurium, Shigella flexneri, and Burkholderia thailandensis activates mouse caspase-11, causing pyroptotic cell death, interleukin-1β processing, and lethal septic shock. How caspase-11 executes these downstream signalling events is largely unknown. Here we show that gasdermin D is essential for caspase-11-dependent pyroptosis and interleukin-1β maturation. A forward genetic screen with ethyl-N-nitrosourea-mutagenized mice links Gsdmd to the intracellular lipopolysaccharide response. Macrophages from Gsdmd(-/-) mice generated by gene targeting also exhibit defective pyroptosis and interleukin-1β secretion induced by cytoplasmic lipopolysaccharide or Gram-negative bacteria. In addition, Gsdmd(-/-) mice are protected from a lethal dose of lipopolysaccharide. Mechanistically, caspase-11 cleaves gasdermin D, and the resulting amino-terminal fragment promotes both pyroptosis and NLRP3-dependent activation of caspase-1 in a cell-intrinsic manner. Our data identify gasdermin D as a critical target of caspase-11 and a key mediator of the host response against Gram-negative bacteria.

  11. Recognition of a 30,000 MW antigen of Giardia muris trophozoites by intestinal IgA from Giardia-infected mice.

    PubMed

    Heyworth, M F; Pappo, J

    1990-08-01

    The principal aims of this work were (i) to identify the molecular weight (MW) of Giardia muris trophozoite antigens that are recognized by IgA in small intestinal secretions from G. muris-infected mice, and (ii) to determine whether mouse intestinal Giardia-specific IgA is directed against trophozoite surfaces. BALB/c mice were infected with G. muris cysts, and intestinal secretions were harvested from these mice at various times after the start of Giardia infection, and from uninfected mice. Flow cytometry showed that intestinal IgA from G. muris-infected mice, but not from uninfected mice, became bound to trophozoite surfaces in vitro. Western blotting of trophozoite proteins with mouse intestinal secretions showed that IgA from Giardia-infected mice reacted specifically with a broad protein band of approximately 30,000 MW. This finding suggests that one or more trophozoite proteins of approximately 30,000 MW are targets for intestinal antibody in mice infected with G. muris.

  12. Recognition of a 30,000 MW antigen of Giardia muris trophozoites by intestinal IgA from Giardia-infected mice.

    PubMed Central

    Heyworth, M F; Pappo, J

    1990-01-01

    The principal aims of this work were (i) to identify the molecular weight (MW) of Giardia muris trophozoite antigens that are recognized by IgA in small intestinal secretions from G. muris-infected mice, and (ii) to determine whether mouse intestinal Giardia-specific IgA is directed against trophozoite surfaces. BALB/c mice were infected with G. muris cysts, and intestinal secretions were harvested from these mice at various times after the start of Giardia infection, and from uninfected mice. Flow cytometry showed that intestinal IgA from G. muris-infected mice, but not from uninfected mice, became bound to trophozoite surfaces in vitro. Western blotting of trophozoite proteins with mouse intestinal secretions showed that IgA from Giardia-infected mice reacted specifically with a broad protein band of approximately 30,000 MW. This finding suggests that one or more trophozoite proteins of approximately 30,000 MW are targets for intestinal antibody in mice infected with G. muris. Images Figure 4 PMID:2394467

  13. Elevated fructosamine concentrations caused by IgA paraproteinemia in two dogs

    PubMed Central

    Kleiter, Miriam; Wolfesberger, Birgitt; Schwendenwein, Ilse; Miller, Ingrid

    2010-01-01

    An 8-year-old male Austrian Pinscher and a 14-year-old male Golden Retriever were presented for evaluation due to unexplainable high fructosamine values despite euglycemia and epistaxis in combination with polydipsia/polyuria, respectively. Blood analysis revealed severe hyperglobulinemia, hypoalbuminemia and markedly elevated fructosamine concentrations in both dogs. Multiple myeloma with IgA-monoclonal gammopathy was diagnosed by serum and urine electrophoresis including immunodetection with an anti-dog IgA antibody and bone marrow aspirations. Diabetes mellitus was excluded by repeated plasma and urine glucose measurements. Fructosamine values were positively correlated with globulin, but negatively correlated with albumin concentrations. These cases suggest that, as in human patients, monoclonal IgA gammopathy should be considered as a possible differential diagnosis for dogs with high fructosamine concentrations. PMID:21113108

  14. RNase P cleaves transient structures in some riboswitches.

    PubMed

    Altman, Sidney; Wesolowski, Donna; Guerrier-Takada, Cecilia; Li, Yong

    2005-08-09

    RNase P from Escherichia coli cleaves the coenzyme B12 riboswitch from E. coli and a similar one from Bacillus subtilis. The cleavage sites do not occur in any recognizable structure, as judged from theoretical schemes that have been drawn for these 5' UTRs. However, it is possible to draw a scheme that is a good representation of the E. coli cleavage site for RNase P and for the cleavage site in B. subtilis. These data indicate that transient structures are important in RNase P cleavage and in riboswitch function. Coenzyme B12 has a small inhibitory effect on E. coli RNase P cleavage of the E. coli riboswitch. Both E. coli RNase P and a partially purified RNase P from Aspergillus nidulans mycelia succeeded in cleaving a putative arginine riboswitch from A. nidulans. The cleavage site may be a representative of another model substrate for eukaryotic RNase P. This 5' UTR controls splicing of the arginase mRNA in A. nidulans. Four other riboswitches in E. coli were not cleaved by RNase P under the conditions tested.

  15. RNase P cleaves transient structures in some riboswitches

    PubMed Central

    Altman, Sidney; Wesolowski, Donna; Guerrier-Takada, Cecilia; Li, Yong

    2005-01-01

    RNase P from Escherichia coli cleaves the coenzyme B12 riboswitch from E. coli and a similar one from Bacillus subtilis. The cleavage sites do not occur in any recognizable structure, as judged from theoretical schemes that have been drawn for these 5′ UTRs. However, it is possible to draw a scheme that is a good representation of the E. coli cleavage site for RNase P and for the cleavage site in B. subtilis. These data indicate that transient structures are important in RNase P cleavage and in riboswitch function. Coenzyme B12 has a small inhibitory effect on E. coli RNase P cleavage of the E. coli riboswitch. Both E. coli RNase P and a partially purified RNase P from Aspergillus nidulans mycelia succeeded in cleaving a putative arginine riboswitch from A. nidulans. The cleavage site may be a representative of another model substrate for eukaryotic RNase P. This 5′ UTR controls splicing of the arginase mRNA in A. nidulans. Four other riboswitches in E. coli were not cleaved by RNase P under the conditions tested. PMID:16061811

  16. Estimating the incidence of rotavirus infection in children from India and Malawi from serial anti-rotavirus IgA titres

    PubMed Central

    Nagelkerke, Nico; Heinsbroek, Ellen; Premkumar, Prasanna S.; Wnęk, Małgorzata; Kang, Gagandeep; French, Neil; Cunliffe, Nigel A.; Bar-Zeev, Naor

    2017-01-01

    Accurate estimates of rotavirus incidence in infants are crucial given disparities in rotavirus vaccine effectiveness from low-income settings. Sero-surveys are a pragmatic means of estimating incidence however serological data is prone to misclassification. This study used mixture models to estimate incidence of rotavirus infection from anti-rotavirus immunoglobulin A (IgA) titres in infants from Vellore, India, and Karonga, Malawi. IgA titres were measured using serum samples collected at 6 month intervals for 36 months from 373 infants from Vellore and 12 months from 66 infants from Karonga. Mixture models (two component Gaussian mixture distributions) were fit to the difference in titres between time points to estimate risk of sero-positivity and derive incidence estimates. A peak incidence of 1.05(95% confidence interval [CI]: 0.64, 1.64) infections per child-year was observed in the first 6 months of life in Vellore. This declined incrementally with each subsequent time interval. Contrastingly in Karonga incidence was greatest in the second 6 months of life (1.41 infections per child year [95% CI: 0.79, 2.29]). This study demonstrates that infants from Vellore experience peak rotavirus incidence earlier than those from Karonga. Identifying such differences in transmission patterns is important in informing vaccine strategy, particularly where vaccine effectiveness is modest. PMID:29287122

  17. [Acute pancreatitis as the presenting feature of an IgA vasculitis: An unusual presentation].

    PubMed

    Fertitta, L; Noel, N; Ackermann, F; Lerolle, N; Benoist, S; Rocher, L; Lambotte, O

    2017-10-01

    IgA vasculitis is a systemic small vessel leukocytoclastic vasculitis characterized by skin purpura, arthritis, abdominal pain and nephritis. Most of the abdominal complications are due to edema and hemorrhage in the small bowel wall, but rarely to acute secondary pancreatitis. Here, we report a 53-year-old woman who presented with acute pancreatitis and, secondarily, developed skin purpura and arthritis at the seventh day of the clinical onset. Biological tests and computed tomographic scan allowed to rule out another cause of pancreatitis and IgA vasculitis was diagnosed as its etiology. The outcome was favorable without any relapse on glucocorticoids. Despite its rarity, pancreatitis is a potential life-threatening complication of IgA vasculitis in which the role of glucocorticoids and immunosuppressive drugs remains uncertain. A prompt elimination of other usual pancreatitis etiologies is mandatory to improve the management of the patients. Copyright © 2017 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  18. Autoimmune responses in patients with linear IgA bullous dermatosis: both autoantibodies and T lymphocytes recognize the NC16A domain of the BP180 molecule.

    PubMed

    Lin, Mong-Shang; Fu, Chang-Ling; Olague-Marchan, Monica; Hacker, Mary K; Zillikens, Detlef; Giudice, George J; Fairley, Janet A

    2002-03-01

    Linear IgA bullous disease (LABD) is an autoimmune skin disease characterized by subepidermal blisters and IgA autoantibodies directed against the epidermal basement membrane zone (BMZ) of the skin. Various antigens have been identified as targets of IgA autoantibodies including BP180, a type II glycoprotein that spans the BMZ and lamina lucida. Previously, we have identified a subset of LABD patients whose sera contained IgA antibodies against the 16th noncollagenous (NC16A) domain of BP180. NC16A was previously shown to harbor epitopes that are recognized by both autoantibodies and T cells from patients with bullous pemphigoid and herpes gestationis and is thought to be associated with the development of these immunobullous diseases. The aim of this study was to determine whether T lymphocytes from LABD patients with anti-NC16A IgA autoantibodies respond to epitopes in the same region of the BP180 protein. Indeed, of the four LABD patients in our study, all had T cells that specifically proliferated in response to NC16A. Moreover, two subfragments of NC16A were identified as the predominant targets of LABD T cells. Further analysis of T cell lines and clones derived from these patients revealed that these cells express a CD4 memory T cell phenotype and secrete a Th1/Th2 mixed-cytokine profile, characteristics similar to those of T cells in bullous pemphigoid patients. Our data suggest that the BP180 protein, typically the NC16A region, is the common target of both cellular and humoral immune responses in some LABD patients. This information helps to further elucidate the autoimmune mechanisms in this disease.

  19. Comparison of flat cleaved and cylindrical diffusing fibers as treatment sources for interstitial photodynamic therapy.

    PubMed

    Baran, Timothy M; Foster, Thomas H

    2014-02-01

    For interstitial photodynamic therapy (iPDT) of bulky tumors, careful treatment planning is required in order to ensure that a therapeutic dose is delivered to the tumor, while minimizing damage to surrounding normal tissue. In clinical contexts, iPDT has typically been performed with either flat cleaved or cylindrical diffusing optical fibers as light sources. Here, the authors directly compare these two source geometries in terms of the number of fibers and duration of treatment required to deliver a prescribed light dose to a tumor volume. Treatment planning software for iPDT was developed based on graphics processing unit enhanced Monte Carlo simulations. This software was used to optimize the number of fibers, total energy delivered by each fiber, and the position of individual fibers in order to deliver a target light dose (D90) to 90% of the tumor volume. Treatment plans were developed using both flat cleaved and cylindrical diffusing fibers, based on tissue volumes derived from CT data from a head and neck cancer patient. Plans were created for four cases: fixed energy per fiber, fixed number of fibers, and in cases where both or neither of these factors were fixed. When the number of source fibers was fixed at eight, treatment plans based on flat cleaved fibers required each to deliver 7180-8080 J in order to deposit 90 J/cm(2) in 90% of the tumor volume. For diffusers, each fiber was required to deliver 2270-2350 J (333-1178 J/cm) in order to achieve this same result. For the case of fibers delivering a fixed 900 J, 13 diffusers or 19 flat cleaved fibers at a spacing of 1 cm were required to deliver the desired dose. With energy per fiber fixed at 2400 J and the number of fibers fixed at eight, diffuser fibers delivered the desired dose to 93% of the tumor volume, while flat cleaved fibers delivered this dose to 79%. With both energy and number of fibers allowed to vary, six diffusers delivering 3485-3600 J were required, compared to ten flat cleaved

  20. Two Antagonistic MALT1 Auto-Cleavage Mechanisms Reveal a Role for TRAF6 to Unleash MALT1 Activation

    PubMed Central

    Renner, Florian; Lam, Stephen; Freuler, Felix; Gerrits, Bertran; Voshol, Johannes; Calzascia, Thomas; Régnier, Catherine H.; Renatus, Martin; Nikolay, Rainer; Israël, Laura; Bornancin, Frédéric

    2017-01-01

    The paracaspase MALT1 has arginine-directed proteolytic activity triggered by engagement of immune receptors. Recruitment of MALT1 into activation complexes is required for MALT1 proteolytic function. Here, co-expression of MALT1 in HEK293 cells, either with activated CARD11 and BCL10 or with TRAF6, was used to explore the mechanism of MALT1 activation at the molecular level. This work identified a prominent self-cleavage site of MALT1 isoform A (MALT1A) at R781 (R770 in MALT1B) and revealed that TRAF6 can activate MALT1 independently of the CBM. Intramolecular cleavage at R781/R770 removes a C-terminal TRAF6-binding site in both MALT1 isoforms, leaving MALT1B devoid of the two key interaction sites with TRAF6. A previously identified auto-proteolysis site of MALT1 at R149 leads to deletion of the death-domain, thereby abolishing interaction with BCL10. By using MALT1 isoforms and cleaved fragments thereof, as well as TRAF6 WT and mutant forms, this work shows that TRAF6 induces N-terminal auto-proteolytic cleavage of MALT1 at R149 and accelerates MALT1 protein turnover. The MALT1 fragment generated by N-terminal self-cleavage at R149 was labile and displayed enhanced signaling properties that required an intact K644 residue, previously shown to be a site for mono-ubiquitination of MALT1. Conversely, C-terminal self-cleavage at R781/R770 hampered the ability for self-cleavage at R149 and stabilized MALT1 by hindering interaction with TRAF6. C-terminal self-cleavage had limited impact on MALT1A but severely reduced MALT1B proteolytic and signaling functions. It also abrogated NF-κB activation by N-terminally cleaved MALT1A. Altogether, this study provides further insights into mechanisms that regulate the scaffolding and activation cycle of MALT1. It also emphasizes the reduced functional capacity of MALT1B as compared to MALT1A. PMID:28052131

  1. Allergen-specific IgG and IgA in serum and bronchoalveolar lavage fluid in a model of experimental feline asthma.

    PubMed

    Norris, C R; Byerly, J R; Decile, K C; Berghaus, R D; Walby, W F; Schelegle, E S; Hyde, D M; Gershwin, L J

    2003-12-15

    Allergic asthma, a Th2 cell driven response to inhaled allergens, has classically been thought of as predominantly mediated by IgE antibodies. To investigate the role of other immunoglobulin classes (e.g., IgG and IgA) in the immunopathogenesis of allergic asthma, levels of these allergen-specific immunoglobulins were measured in serum and mucosal fluids. Bermuda grass allergen (BGA)-specific IgG and IgA ELISAs in serum and bronchoalveolar lavage fluid (BALF) were developed and optimized in an experimental model of BGA-induced feline asthma. Levels of BGA-specific IgG and IgA significantly increased over time in serum and BALF after allergen sensitization. Additionally, these elevated levels of BGA-specific IgG and IgA were seen in conjunction with the development of an asthmatic phenotype indicated by positive intradermal skin tests, enhanced airways hyperreactivity, and increased eosinophil percentages in the BALF.

  2. A transcriptional blueprint for a spiral-cleaving embryo.

    PubMed

    Chou, Hsien-Chao; Pruitt, Margaret M; Bastin, Benjamin R; Schneider, Stephan Q

    2016-08-05

    The spiral cleavage mode of early development is utilized in over one-third of all animal phyla and generates embryonic cells of different size, position, and fate through a conserved set of stereotypic and invariant asymmetric cell divisions. Despite the widespread use of spiral cleavage, regulatory and molecular features for any spiral-cleaving embryo are largely uncharted. To address this gap we use RNA-sequencing on the spiralian model Platynereis dumerilii to capture and quantify the first complete genome-wide transcriptional landscape of early spiral cleavage. RNA-sequencing datasets from seven stages in early Platynereis development, from the zygote to the protrochophore, are described here including the de novo assembly and annotation of ~17,200 Platynereis genes. Depth and quality of the RNA-sequencing datasets allow the identification of the temporal onset and level of transcription for each annotated gene, even if the expression is restricted to a single cell. Over 4000 transcripts are maternally contributed and cleared by the end of the early spiral cleavage phase. Small early waves of zygotic expression are followed by major waves of thousands of genes, demarcating the maternal to zygotic transition shortly after the completion of spiral cleavages in this annelid species. Our comprehensive stage-specific transcriptional analysis of early embryonic stages in Platynereis elucidates the regulatory genome during early spiral embryogenesis and defines the maternal to zygotic transition in Platynereis embryos. This transcriptome assembly provides the first systems-level view of the transcriptional and regulatory landscape for a spiral-cleaving embryo.

  3. Oral Administration of Lactobacillus plantarum Strain AYA Enhances IgA Secretion and Provides Survival Protection against Influenza Virus Infection in Mice

    PubMed Central

    Kikuchi, Yosuke; Kunitoh-Asari, Ayami; Hayakawa, Katsuyuki; Imai, Shinjiro; Kasuya, Kenji; Abe, Kimio; Adachi, Yu; Fukudome, Shin-ichi; Takahashi, Yoshimasa; Hachimura, Satoshi

    2014-01-01

    The mucosal immune system provides the first line of defense against inhaled and ingested pathogenic microbacteria and viruses. This defense system, to a large extent, is mediated by the actions of secretory IgA. In this study, we screened 140 strains of lactic acid bacteria for induction of IgA production by murine Peyer’s patch cells. We selected one strain and named it Lactobacillus plantarum AYA. We found that L. plantarum AYA-induced production of IL-6 in Peyer’s patch dendritic cells, with this production promoting IgA+ B cells to differentiate into IgA-secreting plasma cells. We also observed that oral administration of L. plantarum AYA in mice caused an increase in IgA production in the small intestine and lung. This production of IgA correlated strongly with protective ability, with the treated mice surviving longer than the control mice after lethal influenza virus infection. Our data therefore reveals a novel immunoregulatory role of the L. plantarum AYA strain which enhances mucosal IgA production and provides protection against respiratory influenza virus infection. PMID:24466081

  4. Oral administration of Lactobacillus plantarum strain AYA enhances IgA secretion and provides survival protection against influenza virus infection in mice.

    PubMed

    Kikuchi, Yosuke; Kunitoh-Asari, Ayami; Hayakawa, Katsuyuki; Imai, Shinjiro; Kasuya, Kenji; Abe, Kimio; Adachi, Yu; Fukudome, Shin-Ichi; Takahashi, Yoshimasa; Hachimura, Satoshi

    2014-01-01

    The mucosal immune system provides the first line of defense against inhaled and ingested pathogenic microbacteria and viruses. This defense system, to a large extent, is mediated by the actions of secretory IgA. In this study, we screened 140 strains of lactic acid bacteria for induction of IgA production by murine Peyer's patch cells. We selected one strain and named it Lactobacillus plantarum AYA. We found that L. plantarum AYA-induced production of IL-6 in Peyer's patch dendritic cells, with this production promoting IgA(+) B cells to differentiate into IgA-secreting plasma cells. We also observed that oral administration of L. plantarum AYA in mice caused an increase in IgA production in the small intestine and lung. This production of IgA correlated strongly with protective ability, with the treated mice surviving longer than the control mice after lethal influenza virus infection. Our data therefore reveals a novel immunoregulatory role of the L. plantarum AYA strain which enhances mucosal IgA production and provides protection against respiratory influenza virus infection.

  5. EB virus-specific IgA in serum of patients with infectious mononucleosis and of healthy people of different ages.

    PubMed

    Edwards, J M; Woodroof, M

    1979-10-01

    The following sera were tested for EB virus-specific IgA: serial sera from 61 cases of infectious mononucleosis (IM) and from 195 EBV IgG positive healthy students; single sera from each of 1469 persons of different ages, 63 cases of untreated Hodgkin's disease, and 22 neonates. EBV specific IgA was found in the sera from 88% of cases of IM, from 18.5% of EBV IgG positive healthy students, and in 13.5% of repeat samples from the same students three years later. The incidence of EBV IgA varied from 5 to 30% at different ages in single sera from EBV IgG positive persons aged 2 to 70 years. The higher percentages occurred in the age groups where recent sero-conversion rates were high. Fifteen percent of sera from cases of Hodgkin's disease were positive for EBV IgA, an incidence similar to that for healthy adults in the age group 25-45 years. None of the EBV IgG positive sera from neonates gave a positive reaction for EBV IGA.

  6. Evolution of the Iga Heavy Chain Gene in the Genus Mus

    PubMed Central

    Osborne, B. A.; Golde, T. E.; Schwartz, R. L.; Rudikoff, S.

    1988-01-01

    To examine questions of immunoglobulin gene evolution, the IgA α heavy chain gene from Mus pahari, an evolutionarily distant relative to Mus musculus domesticus, was cloned and sequenced. The sequence, when compared to the IgA gene of BALB/c or human, demonstrated that the IgA gene is evolving in a mosaic fashion with the hinge region accumulating mutations most rapidly and the third domain at a considerably lower frequency. In spite of this pronounced accumulation of mutations, the hinge region appears to maintain the conformation of a random coil. A marked propensity to accumulate replacement over silent site changes in the coding regions was noted, as was a definite codon bias. The possibility that these two phenomena are interrelated is discussed. PMID:2842228

  7. Study of the IGA/SCC behavior of Alloy 600 and 690 in high temperature solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsujikawa, S.; Yashima, S.; Ohnishi, K.

    1995-09-01

    IGA/SCC of Alloy 600 steam generator (SG) tubes in the secondary side has been recognized as a matter of great concern for PWRs. IGA/SCC behavior of Alloy 600 and 690 in high temperature solutions were studied using CERT method under potentiostatic conditions. The IGA/SCC susceptible regions were investigated as the function of pH and electrode potential. To understand the cause of IGA/SCC, the electrochemical measurements and surface film analysis were also performed in acidic and alkaline solutions. To verify the results of CERT test, the long term model boiler tests were also carried out. Thermally treated Alloy 690 showed highermore » IGA/SCC resistance than Alloy 600 under both acid and alkaline conditions.« less

  8. A Neutral Thermostable β-1,4-Glucanase from Humicola insolens Y1 with Potential for Applications in Various Industries

    PubMed Central

    Zhang, Wei; Huang, Huoqing; Shi, Pengjun; Luo, Huiying; Liu, Bo; Zhang, Yuhong; Zhang, Zhifang; Fan, Yunliu; Yao, Bin

    2015-01-01

    We cloned a new glycoside hydrolase family 6 gene, Hicel6C, from the thermophilic fungus Humicola insolens Y1 and expressed it in Pichia pastoris. Using barley β-glucan as a substrate, recombinant HiCel6C protein exhibited neutral pH (6.5) and high temperature (70°C) optima. Distinct from most reported acidic fungal endo-β-1,4-glucanases, HiCel6C was alkali-tolerant, retaining greater than 98.0, 61.2, and 27.6% of peak activity at pH 8.0, 9.0, and 10.0, respectively, and exhibited good stability over a wide pH range (pH 5.0−11.0) and at temperatures up to 60°C. The K m and V max values of HiCel6C for barley β-glucan were 1.29 mg/mL and 752 μmol/min·mg, respectively. HiCel6C was strictly specific for the β-1,4-glucoside linkage exhibiting activity toward barley β-glucan, lichenan, and carboxy methylcellulose sodium salt (CMC-Na), but not toward laminarin (1,3-β-glucan). HiCel6C cleaved the internal glycosidic linkages of cellooligosaccharides randomly and thus represents an endo-cleaving enzyme. The predominant product of polysaccharide hydrolysis by HiCel6C was cellobiose, suggesting that it functions by an endo-processive mechanism. The favorable properties of HiCel6C make it a good candidate for basic research and for applications in the textile and brewing industries. PMID:25909505

  9. Crystal growth of Bi{sub 2}Te{sub 3} and noble cleaved (0001) surface properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Atuchin, V.V., E-mail: atuchin@thermo.isp.nsc.ru; Functional Electronics Laboratory, Tomsk State University, Tomsk 634050; Golyashov, V.A.

    2016-04-15

    A high quality Bi{sub 2}Te{sub 3} crystal has been grown by Bridgman method with the use of rotating heat field. The phase purity and bulk structural quality of the crystal have been verified by XRD analysis and rocking curve observation. The atomically smooth Bi{sub 2}Te{sub 3}(0001) surface with an excellent crystallographic quality is formed by cleavage in the air. The chemical and microstructural properties of the surface have been evaluated with RHEED, AFM, STM, SE and XPS. The Bi{sub 2}Te{sub 3}(0001) cleaved surface is formed by atomically smooth terraces with the height of the elemental step of ~1.04±0.1 nm, asmore » estimated by AFM. There is no surface oxidation process detected over a month keeping in the air at normal conditions, as shown by comparative core level photoelectron spectroscopy. - Graphical abstract: A high quality Bi{sub 2}Te{sub 3} crystal has been grown by Bridgman method with the use of rotating heat field and the Bi{sub 2}Te{sub 3}(0001) cleaved surface has been evaluated with RHEED, AFM, STM, SE and XPS. - Highlights: • High-quality Bi{sub 2}Te{sub 3} crystal of 10 mm in diameter and 50 mm long have been grown. • The high-purity cleaved Bi{sub 2}Te{sub 3}(0001) surface has been evaluated by RHEED, AFM, STM and XPS methods. • The Bi{sub 2}Te{sub 3} surface covered by atomically smooth (0001) terraces is chemically stable for a long time.« less

  10. Electrical characteristics of n-GaN Schottky contacts on cleaved surfaces of free-standing substrates: Metal work function dependence of Schottky barrier height

    NASA Astrophysics Data System (ADS)

    Imadate, Hiroyoshi; Mishima, Tomoyoshi; Shiojima, Kenji

    2018-04-01

    We report the electrical characteristics of Schottky contacts with nine different metals (Ag, Ti, Cr, W, Mo, Au, Pd, Ni, and Pt) formed on clean m-plane surfaces by cleaving freestanding GaN substrates, compared with these of contacts on Ga-polar c-plane n-GaN surfaces grown on GaN substrates. The n-values from the forward current–voltage (I–V) characteristics are as good as 1.02–1.18 and 1.02–1.09 for the m- and c-plane samples, respectively. We found that the reverse I–V curves of both samples can be explained by the thermionic field emission theory, and that the Schottky barrier height of the cleaved m-plane contacts shows a metal work function dependence.

  11. Processing of MOPC 315 immunoglobulin A oligosaccharides: evidence for endoplasmic reticulum and trans Golgi alpha 1,2-mannosidase activity

    PubMed Central

    1984-01-01

    The processing of asparagine-linked oligosaccharides on the alpha- chains of an immunoglobulin A (IgA) has been investigated using MOPC 315 murine plasmacytoma cells. These cells secrete IgA containing complex-type oligosaccharides that were not sensitive to endo-beta-N- acetylglucosaminidase H. In contrast, oligosaccharides present on the intracellular alpha-chain precursor were of the high mannose-type, remaining sensitive to endo-beta-N-acetylglucosaminidase H despite a long intracellular half-life of 2-3 h. The major [3H]mannose-labeled alpha-chain oligosaccharides identified after a 20-min pulse were Man8GlcNAc2 and Man9GlcNAc2. Following chase incubations, the major oligosaccharide accumulating intracellularly was Man6GlcNAc2, which was shown to contain a single alpha 1,2-linked mannose residue. Conversion of Man6GlcNAc2 to complex-type oligosaccharides occurred at the time of secretion since appreciable amounts of Man5GlcNAc2 or further processed structures could not be detected intracellularly. The subcellular locations of the alpha 1,2-mannosidase activities were studied using carbonyl cyanide m-chlorophenylhydrazone and monensin. Despite inhibiting the secretion of IgA, these inhibitors of protein migration did not effect the initial processing of Man9GlcNAc2 to Man6GlcNAc2. Furthermore, no large accumulation of Man5GlcNAc2 occurred, indicating the presence of two subcellular locations of alpha 1,2-mannosidase activity involved in oligosaccharide processing in MOPC 315 cells. Thus, the first three alpha 1,2-linked mannose residues were removed shortly after the alpha-chain was glycosylated, most likely in rough endoplasmic reticulum, since this processing occurred in the presence of carbonyl cyanide m-chlorophenylhydrazone. However, the removal of the final alpha 1,2-linked mannose residue as well as subsequent carbohydrate processing occurred just before IgA secretion, most likely in the trans Golgi complex since processing of Man6GlcNAc2 to Man5GlcNAc2

  12. Processing of MOPC 315 immunoglobulin A oligosaccharides: evidence for endoplasmic reticulum and trans Golgi alpha 1,2-mannosidase activity.

    PubMed

    Hickman, S; Theodorakis, J L; Greco, J M; Brown, P H

    1984-02-01

    The processing of asparagine-linked oligosaccharides on the alpha-chains of an immunoglobulin A (IgA) has been investigated using MOPC 315 murine plasmacytoma cells. These cells secrete IgA containing complex-type oligosaccharides that were not sensitive to endo-beta-N-acetylglucosaminidase H. In contrast, oligosaccharides present on the intracellular alpha-chain precursor were of the high mannose-type, remaining sensitive to endo-beta-N-acetylglucosaminidase H despite a long intracellular half-life of 2-3 h. The major [3H]mannose-labeled alpha-chain oligosaccharides identified after a 20-min pulse were Man8GlcNAc2 and Man9GlcNAc2. Following chase incubations, the major oligosaccharide accumulating intracellularly was Man6GlcNAc2, which was shown to contain a single alpha 1,2-linked mannose residue. Conversion of Man6GlcNAc2 to complex-type oligosaccharides occurred at the time of secretion since appreciable amounts of Man5GlcNAc2 or further processed structures could not be detected intracellularly. The subcellular locations of the alpha 1,2-mannosidase activities were studied using carbonyl cyanide m-chlorophenylhydrazone and monensin. Despite inhibiting the secretion of IgA, these inhibitors of protein migration did not effect the initial processing of Man9GlcNAc2 to Man6GlcNAc2. Furthermore, no large accumulation of Man5GlcNAc2 occurred, indicating the presence of two subcellular locations of alpha 1,2-mannosidase activity involved in oligosaccharide processing in MOPC 315 cells. Thus, the first three alpha 1,2-linked mannose residues were removed shortly after the alpha-chain was glycosylated, most likely in rough endoplasmic reticulum, since this processing occurred in the presence of carbonyl cyanide m-chlorophenylhydrazone. However, the removal of the final alpha 1,2-linked mannose residue as well as subsequent carbohydrate processing occurred just before IgA secretion, most likely in the trans Golgi complex since processing of Man6GlcNAc2 to Man5GlcNAc2

  13. Mannan adjuvants intranasally administered inactivated influenza virus in mice rendering low doses inductive of strong serum IgG and IgA in the lung.

    PubMed

    Proudfoot, Owen; Esparon, Sandra; Tang, Choon-Kit; Laurie, Karen; Barr, Ian; Pietersz, Geoffrey

    2015-02-26

    H1N1 influenza viruses mutate rapidly, rendering vaccines developed in any given year relatively ineffective in subsequent years. Thus it is necessary to generate new vaccines every year, but this is time-consuming and resource-intensive. Should a highly virulent influenza strain capable of human-to-human transmission emerge, these factors will severely limit the number of people that can be effectively immunised against that strain in time to prevent a pandemic. An adjuvant and mode of administration capable of rendering ordinarily unprotective vaccine doses protective would thus be highly advantageous. The carbohydrate mannan was conjugated to whole inactivated H1N1 influenza virus at a range of ratios, and mixed with it at a range of ratios, and various doses of the resulting preparations were administered to mice via the intranasal (IN) route. Serum immunity was assessed via antigen-specific IgG ELISA and the haemagglutination-inhibition (HI) assay, and mucosal immunity was assessed via IgA ELISA of bronchio-alveolar lavages. IN-administered inactivated H1N1 mixed with mannan induced higher serum IgG and respiratory-tract IgA than inactivated H1N1 conjugated to mannan, and HIN1 alone. Adjuvantation was mannan-dose-dependent, with 100 μg of mannan adjuvanting 1 μg of H1N1 more effectively than 10 or 50 μg of mannan. Serum samples from mice immunised with 1 μg H1N1 adjuvanted with 10 μg mannan did not inhibit agglutination of red blood cells (RBCs) at a dilution factor of 10 in the HI assay, but samples resulting from adjuvantation with 50 and 100 μg mannan inhibited agglutination at dilution factors of ≥ 40. Both serum IgG1 and IgG2a were induced by IN mannan-adjuvanted H1N1 vaccination, suggesting the induction of humoral and cellular immunity. Mixing 100 μg of mannan with 1 μg of inactivated H1N1 adjuvanted the vaccine in mice, such that IN immunisation induced higher serum IgG and respiratory tract IgA than immunisation with virus alone. The

  14. Proteolytic cleavage by the inner membrane peptidase (IMP) complex or Oct1 peptidase controls the localization of the yeast peroxiredoxin Prx1 to distinct mitochondrial compartments.

    PubMed

    Gomes, Fernando; Palma, Flávio Romero; Barros, Mario H; Tsuchida, Eduardo T; Turano, Helena G; Alegria, Thiago G P; Demasi, Marilene; Netto, Luis E S

    2017-10-13

    Yeast Prx1 is a mitochondrial 1-Cys peroxiredoxin that catalyzes the reduction of endogenously generated H 2 O 2 Prx1 is synthesized on cytosolic ribosomes as a preprotein with a cleavable N-terminal presequence that is the mitochondrial targeting signal, but the mechanisms underlying Prx1 distribution to distinct mitochondrial subcompartments are unknown. Here, we provide direct evidence of the following dual mitochondrial localization of Prx1: a soluble form in the intermembrane space and a form in the matrix weakly associated with the inner mitochondrial membrane. We show that Prx1 sorting into the intermembrane space likely involves the release of the protein precursor within the lipid bilayer of the inner membrane, followed by cleavage by the inner membrane peptidase. We also found that during its import into the matrix compartment, Prx1 is sequentially cleaved by mitochondrial processing peptidase and then by octapeptidyl aminopeptidase 1 (Oct1). Oct1 cleaved eight amino acid residues from the N-terminal region of Prx1 inside the matrix, without interfering with its peroxidase activity in vitro Remarkably, the processing of peroxiredoxin (Prx) proteins by Oct1 appears to be an evolutionarily conserved process because yeast Oct1 could cleave the human mitochondrial peroxiredoxin Prx3 when expressed in Saccharomyces cerevisiae Altogether, the processing of peroxiredoxins by Imp2 or Oct1 likely represents systems that control the localization of Prxs into distinct compartments and thereby contribute to various mitochondrial redox processes. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Photoelectron Holographic Atomic Arrangement Imaging of Cleaved Bimetal-intercalated Graphite Superconductor Surface

    PubMed Central

    Matsui, Fumihiko; Eguchi, Ritsuko; Nishiyama, Saki; Izumi, Masanari; Uesugi, Eri; Goto, Hidenori; Matsushita, Tomohiro; Sugita, Kenji; Daimon, Hiroshi; Hamamoto, Yuji; Hamada, Ikutaro; Morikawa, Yoshitada; Kubozono, Yoshihiro

    2016-01-01

    From the C 1s and K 2p photoelectron holograms, we directly reconstructed atomic images of the cleaved surface of a bimetal-intercalated graphite superconductor, (Ca, K)C8, which differed substantially from the expected bulk crystal structure based on x-ray diffraction (XRD) measurements. Graphene atomic images were collected in the in-plane cross sections of the layers 3.3 Å and 5.7 Å above the photoelectron emitter C atom and the stacking structures were determined as AB- and AA-type, respectively. The intercalant metal atom layer was found between two AA-stacked graphenes. The K atomic image revealing 2 × 2 periodicity, occupying every second centre site of C hexagonal columns, was reconstructed, and the Ca 2p peak intensity in the photoelectron spectra of (Ca, K)C8 from the cleaved surface was less than a few hundredths of the K 2p peak intensity. These observations indicated that cleavage preferentially occurs at the KC8 layers containing no Ca atoms. PMID:27811975

  16. Endonuclease EEPD1 Is a Gatekeeper for Repair of Stressed Replication Forks*

    PubMed Central

    Kim, Hyun-Suk; Nickoloff, Jac A.; Wu, Yuehan; Williamson, Elizabeth A.; Sidhu, Gurjit Singh; Reinert, Brian L.; Jaiswal, Aruna S.; Srinivasan, Gayathri; Patel, Bhavita; Kong, Kimi; Burma, Sandeep; Lee, Suk-Hee; Hromas, Robert A.

    2017-01-01

    Replication is not as continuous as once thought, with DNA damage frequently stalling replication forks. Aberrant repair of stressed replication forks can result in cell death or genome instability and resulting transformation to malignancy. Stressed replication forks are most commonly repaired via homologous recombination (HR), which begins with 5′ end resection, mediated by exonuclease complexes, one of which contains Exo1. However, Exo1 requires free 5′-DNA ends upon which to act, and these are not commonly present in non-reversed stalled replication forks. To generate a free 5′ end, stalled replication forks must therefore be cleaved. Although several candidate endonucleases have been implicated in cleavage of stalled replication forks to permit end resection, the identity of such an endonuclease remains elusive. Here we show that the 5′-endonuclease EEPD1 cleaves replication forks at the junction between the lagging parental strand and the unreplicated DNA parental double strands. This cleavage creates the structure that Exo1 requires for 5′ end resection and HR initiation. We observed that EEPD1 and Exo1 interact constitutively, and Exo1 repairs stalled replication forks poorly without EEPD1. Thus, EEPD1 performs a gatekeeper function for replication fork repair by mediating the fork cleavage that permits initiation of HR-mediated repair and restart of stressed forks. PMID:28049724

  17. Fixation of Oligosaccharides to a Surface May Increase the Susceptibility to Human Parainfluenza Virus 1, 2, or 3 Hemagglutinin-Neuraminidase▿†

    PubMed Central

    Tappert, Mary M.; Smith, David F.; Air, Gillian M.

    2011-01-01

    The hemagglutinin-neuraminidase (HN) protein of human parainfluenza viruses (hPIVs) both binds (H) and cleaves (N) oligosaccharides that contain N-acetylneuraminic acid (Neu5Ac). H is thought to correspond to receptor binding and N to receptor-destroying activity. At present, N′s role in infection remains unclear: does it destroy only receptors, or are there other targets? We previously demonstrated that hPIV1 and 3 HNs bind to oligosaccharides containing the motif Neu5Acα2-3Galβ1-4GlcNAc (M. Amonsen, D. F. Smith, R. D. Cummings, and G. M. Air, J. Virol. 81:8341–8345, 2007). In the present study, we tested the binding specificity of hPIV2 on the Consortium for Functional Glycomics' glycan array and found that hPIV2 binds to oligosaccharides containing the same motif. We determined the specificities of N on red blood cells, soluble small-molecule and glycoprotein substrates, and the glycan array and compared them to the specificities of H. hPIV2 and -3, but not hPIV1, cleaved their ligands on red blood cells. hPIV1, -2, and -3 cleaved their NeuAcα2-3 ligands on the glycan array; hPIV2 and -3 also cleaved NeuAcα2-6 ligands bound by influenza A virus. While all three HNs exhibited similar affinities for all cleavable soluble substrates, their activities were 5- to 10-fold higher on small molecules than on glycoproteins. In addition, some soluble glycoproteins were not cleaved, despite containing oligosaccharides that were cleaved on the glycan array. We conclude that the susceptibility of an oligosaccharide substrate to N increases when the substrate is fixed to a surface. These findings suggest that HN may undergo a conformational change that activates N upon receptor binding at a cell surface. PMID:21917945

  18. Diagnostic value of detecting specific IgA and IgM with recombinant Trypanosoma cruzi antigens in congenital Chagas' disease.

    PubMed

    Lorca, M; Veloso, C; Munoz, P; Bahamonde, M I; Garcia, A

    1995-06-01

    The present study compares the early diagnosis of congenital Chagas' disease with a DOT assay using recombinant antigens with immunofluorescence antibody testing (IFAT) and an enzyme-linked immunosorbent assay (ELISA). The studies were performed using cord blood and sera of 12 infected newborns (group I) and 12 uninfected ones born to Trypanosoma cruzi-infected mothers (group II). Conventional IFAT and ELISA showed positive results for IgG at high titers, in infants and mothers of both groups; IgA antibodies were detected by ELISA in four of the infected infants and IgM was detected in two of them. All sera of the uninfected infants were negative for IgA and IgM in the ELISA. Application of a DOT assay using eight recombinant T. cruzi antigens allowed detection of specific IgA in the cord blood of six of the infected cases and IgM in eight of them. Repetition of these serologic tests in samples obtained during a monthly follow-up gave positive results for IgA in two of the initially negative infants of group I and for IgM in four of them. This means that diagnosis of congenital T. cruzi infection was confirmed, through demonstration of specific IgM, in all infected infants, and of IgA in eight of them. The importance of late detection of IgM in siblings born of infected mothers is discussed. The detection of IgM and IgA in sera obtained after birth is believed to be due to a congenital transmission of the parasite that occurred late in pregnancy. No IgA or IgM antibodies could be detected by the DOT assay in the sera of the negative controls.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. A New Approach to Produce HIV-1 Envelope Trimers

    PubMed Central

    AlSalmi, Wadad; Mahalingam, Marthandan; Ananthaswamy, Neeti; Hamlin, Christopher; Flores, Dalia; Gao, Guofen; Rao, Venigalla B.

    2015-01-01

    The trimeric envelope spike of HIV-1 mediates virus entry into human cells. The exposed part of the trimer, gp140, consists of two noncovalently associated subunits, gp120 and gp41 ectodomain. A recombinant vaccine that mimics the native trimer might elicit entry-blocking antibodies and prevent virus infection. However, preparation of authentic HIV-1 trimers has been challenging. Recently, an affinity column containing the broadly neutralizing antibody 2G12 has been used to capture recombinant gp140 and prepare trimers from clade A BG505 that naturally produces stable trimers. However, this antibody-based approach may not be as effective for the diverse HIV-1 strains with different epitope signatures. Here, we report a new and simple approach to produce HIV-1 envelope trimers. The C terminus of gp140 was attached to Strep-tag II with a long linker separating the tag from the massive trimer base and glycan shield. This allowed capture of nearly homogeneous gp140 directly from the culture medium. Cleaved, uncleaved, and fully or partially glycosylated trimers from different clade viruses were produced. Extensive biochemical characterizations showed that cleavage of gp140 was not essential for trimerization, but it triggered a conformational change that channels trimers into correct glycosylation pathways, generating compact three-blade propeller-shaped trimers. Uncleaved trimers entered aberrant pathways, resulting in hyperglycosylation, nonspecific cross-linking, and conformational heterogeneity. Even the cleaved trimers showed microheterogeneity in gp41 glycosylation. These studies established a broadly applicable HIV-1 trimer production system as well as generating new insights into their assembly and maturation that collectively bear on the HIV-1 vaccine design. PMID:26088135

  20. CTA1-DD adjuvant promotes strong immunity against human immunodeficiency virus type 1 envelope glycoproteins following mucosal immunization.

    PubMed

    Sundling, Christopher; Schön, Karin; Mörner, Andreas; Forsell, Mattias N E; Wyatt, Richard T; Thorstensson, Rigmor; Karlsson Hedestam, Gunilla B; Lycke, Nils Y

    2008-12-01

    Strategies to induce potent and broad antibody responses against the human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins (Env) at both systemic and mucosal sites represent a central goal for HIV-1 vaccine development. Here, we show that the non-toxic CTA1-DD adjuvant promoted mucosal and systemic humoral and cell-mediated immune responses following intranasal (i.n.) immunizations with trimeric or monomeric forms of HIV-1 Env in mice and in non-human primates. Env-specific IgG subclasses in the serum of immunized mice reflected a balanced Th1/Th2 type of response. Strikingly, i.n. immunizations with Env and the CTA1-DD adjuvant induced substantial levels of mucosal anti-Env IgA in bronchial alveolar lavage and also detectable levels in vaginal secretions. By contrast, parenteral immunizations of Env formulated in Ribi did not stimulate mucosal IgA responses, while the two adjuvants induced a similar distribution of Env-specific IgG-subclasses in serum. A single parenteral boost with Env in Ribi adjuvant into mice previously primed i.n. with Env and CTA1-DD, augmented the serum anti-Env IgG levels to similar magnitudes as those observed after three intraperitoneal immunizations with Env in Ribi. The augmenting potency of CTA1-DD was similar to that of LTK63 or CpG oligodeoxynucleotides (ODN). However, in contrast to CpG ODN, the effect of CTA1-DD and LTK63 appeared to be independent of MyD88 and toll-like receptor signalling. This is the first demonstration that CTA1-DD augments specific immune responses also in non-human primates, suggesting that this adjuvant could be explored further as a clinically safe mucosal vaccine adjuvant for humoral and cell-mediated immunity against HIV-1 Env.

  1. Comparison of flat cleaved and cylindrical diffusing fibers as treatment sources for interstitial photodynamic therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baran, Timothy M., E-mail: timothy.baran@rochester.edu; Foster, Thomas H.

    Purpose: For interstitial photodynamic therapy (iPDT) of bulky tumors, careful treatment planning is required in order to ensure that a therapeutic dose is delivered to the tumor, while minimizing damage to surrounding normal tissue. In clinical contexts, iPDT has typically been performed with either flat cleaved or cylindrical diffusing optical fibers as light sources. Here, the authors directly compare these two source geometries in terms of the number of fibers and duration of treatment required to deliver a prescribed light dose to a tumor volume. Methods: Treatment planning software for iPDT was developed based on graphics processing unit enhanced Montemore » Carlo simulations. This software was used to optimize the number of fibers, total energy delivered by each fiber, and the position of individual fibers in order to deliver a target light dose (D{sub 90}) to 90% of the tumor volume. Treatment plans were developed using both flat cleaved and cylindrical diffusing fibers, based on tissue volumes derived from CT data from a head and neck cancer patient. Plans were created for four cases: fixed energy per fiber, fixed number of fibers, and in cases where both or neither of these factors were fixed. Results: When the number of source fibers was fixed at eight, treatment plans based on flat cleaved fibers required each to deliver 7180–8080 J in order to deposit 90 J/cm{sup 2} in 90% of the tumor volume. For diffusers, each fiber was required to deliver 2270–2350 J (333–1178 J/cm) in order to achieve this same result. For the case of fibers delivering a fixed 900 J, 13 diffusers or 19 flat cleaved fibers at a spacing of 1 cm were required to deliver the desired dose. With energy per fiber fixed at 2400 J and the number of fibers fixed at eight, diffuser fibers delivered the desired dose to 93% of the tumor volume, while flat cleaved fibers delivered this dose to 79%. With both energy and number of fibers allowed to vary, six diffusers delivering 3485

  2. Placental Transfer of Maternally-Derived IgA Precludes the Use of Guthrie Card Eluates as a Screening Tool for Primary Immunodeficiency Diseases

    PubMed Central

    Borte, Stephan; Janzi, Magdalena; Pan-Hammarström, Qiang; von Döbeln, Ulrika; Nordvall, Lennart; Winiarski, Jacek; Fasth, Anders; Hammarström, Lennart

    2012-01-01

    There is a need for neonatal screening tools to improve the long-term clinical outcome of patients with primary immunodeficiency diseases (PID). Recently, a PCR-based screening method for both TRECs and KRECs using Guthrie card samples has been developed. However, the applicability of these excision circle assays is limited to patients with severe T or B cell lymphopenia (SCID, XLA and A-T), whereas the most common forms of PID are not detected. Absence of serum IgA is seen in a major fraction of patients with immunological defects. As serum IgA in newborns is considered to be of fetal origin, eluates from routinely collected dried blood spot samples might thus be suitable for identification of children with PID. To assess the applicability of such screening assays, stored Guthrie card samples were obtained from 47 patients with various forms of primary immunodeficiency diseases (SCID, XLA, A-T, HIGM and IgAD), 20 individuals with normal serum IgA levels born to IgA-deficient mothers and 51 matched healthy newborns. Surprisingly, normal serum IgA levels were found in all SCID, XLA, A-T and HIGM patients and, additionally, in all those IgAD patients born to IgA-sufficient mothers. Conversely, no serum IgA was found in any of the 16 IgAD patients born by IgA-deficient mothers. Moreover, half of the IgA-sufficient individuals born by IgA-deficient mothers also lacked IgA at birth whereas no IgA-deficient individuals were found among the controls. IgA in neonatal dried blood samples thus appears to be of both maternal and fetal origin and precludes its use as a reliable marker for neonatal screening of primary immunodeficiency diseases. PMID:22916257

  3. Placental transfer of maternally-derived IgA precludes the use of guthrie card eluates as a screening tool for primary immunodeficiency diseases.

    PubMed

    Borte, Stephan; Janzi, Magdalena; Pan-Hammarström, Qiang; von Döbeln, Ulrika; Nordvall, Lennart; Winiarski, Jacek; Fasth, Anders; Hammarström, Lennart

    2012-01-01

    There is a need for neonatal screening tools to improve the long-term clinical outcome of patients with primary immunodeficiency diseases (PID). Recently, a PCR-based screening method for both TRECs and KRECs using Guthrie card samples has been developed. However, the applicability of these excision circle assays is limited to patients with severe T or B cell lymphopenia (SCID, XLA and A-T), whereas the most common forms of PID are not detected. Absence of serum IgA is seen in a major fraction of patients with immunological defects. As serum IgA in newborns is considered to be of fetal origin, eluates from routinely collected dried blood spot samples might thus be suitable for identification of children with PID. To assess the applicability of such screening assays, stored Guthrie card samples were obtained from 47 patients with various forms of primary immunodeficiency diseases (SCID, XLA, A-T, HIGM and IgAD), 20 individuals with normal serum IgA levels born to IgA-deficient mothers and 51 matched healthy newborns. Surprisingly, normal serum IgA levels were found in all SCID, XLA, A-T and HIGM patients and, additionally, in all those IgAD patients born to IgA-sufficient mothers. Conversely, no serum IgA was found in any of the 16 IgAD patients born by IgA-deficient mothers. Moreover, half of the IgA-sufficient individuals born by IgA-deficient mothers also lacked IgA at birth whereas no IgA-deficient individuals were found among the controls. IgA in neonatal dried blood samples thus appears to be of both maternal and fetal origin and precludes its use as a reliable marker for neonatal screening of primary immunodeficiency diseases.

  4. IgA rheumatoid factor as a serological predictor of poor response to tumour necrosis factor α inhibitors in rheumatoid arthritis.

    PubMed

    Sakthiswary, Rajalingham; Shaharir, Syahrul S; Mohd Said, Mohd S; Asrul, Abdul W; Shahril, Nor S

    2014-11-01

    The main objective of this study is to elucidate the role of immunoglobulin A (IgA) rheumatoid factor (RF) in predicting the clinical response to tumour necrosis factor α inhibitors (TNFi) among patients with rheumatoid arthritis (RA). We recruited all patients with RA who were ever on TNFi for a minimum duration of 3 months at our centre. Based on the European League Against Rheumatism response criteria, subjects were further divided into responders and non-responders. Age-matched RA patients who were on conventional disease-modifying anti-rheumatic drugs and in remission were enrolled as controls. Subjects were tested for quantitative values of IgA, IgM, IgG RF and anti-citrulinated cyclic peptides (CCP). Further, all subjects were assessed for the disease activity score that includes 28 joints (DAS28) and Stanford Health Assessment Questionnaire (HAQ) 8-item Disability Index (HAQ-DI). A total of 31 subjects with RA who had received TNFi and 15 controls were enrolled in this study. There was a trend for the non-responders (n = 10) to have higher levels of all isotypes of RF and anti-CCP. However, only the IgA RF and anti-CCP levels were significantly higher in the non-responder group compared to the responders and controls (P = 0.001, P = 0.034, respectively). On multivariate analysis, only the IgA RF remained significant (OR 0.989; 95% CI 0.980-0.999; P = 0.026). IgA RF is potentially a novel predictor of response to TNFi in RA patients. Testing for pretreatment IgA RF levels could be a reasonable consideration before commencement of TNFi. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  5. Elevated factor H-related protein 1 and factor H pathogenic variants decrease complement regulation in IgA nephropathy.

    PubMed

    Tortajada, Agustín; Gutiérrez, Eduardo; Goicoechea de Jorge, Elena; Anter, Jaouad; Segarra, Alfons; Espinosa, Mario; Blasco, Miquel; Roman, Elena; Marco, Helena; Quintana, Luis F; Gutiérrez, Josué; Pinto, Sheila; Lopez-Trascasa, Margarita; Praga, Manuel; Rodriguez de Córdoba, Santiago

    2017-10-01

    IgA nephropathy (IgAN), a frequent cause of chronic kidney disease worldwide, is characterized by mesangial deposition of galactose-deficient IgA1-containing immune complexes. Complement involvement in IgAN pathogenesis is suggested by the glomerular deposition of complement components and the strong protection from IgAN development conferred by the deletion of the CFHR3 and CFHR1 genes (Δ CFHR3-CFHR1 ). Here we searched for correlations between clinical progression and levels of factor H (FH) and FH-related protein 1 (FHR-1) using well-characterized patient cohorts consisting of 112 patients with IgAN, 46 with non-complement-related autosomal dominant polycystic kidney disease (ADPKD), and 76 control individuals. Patients with either IgAN or ADPKD presented normal FH but abnormally elevated FHR-1 levels and FHR-1/FH ratios compared to control individuals. Highest FHR-1 levels and FHR-1/FH ratios are found in patients with IgAN with disease progression and in patients with ADPKD who have reached chronic kidney disease, suggesting that renal function impairment elevates the FHR-1/FH ratio, which may increase FHR-1/FH competition for activated C3 fragments. Interestingly, Δ CFHR3-CFHR1 homozygotes are protected from IgAN, but not from ADPKD, and we found five IgAN patients with low FH carrying CFH or CFI pathogenic variants. These data support a decreased FH activity in IgAN due to increased FHR-1/FH competition or pathogenic CFH variants. They also suggest that alternative pathway complement activation in patients with IgAN, initially triggered by galactose-deficient IgA1-containing immune complexes, may exacerbate in a vicious circle as renal function deterioration increase FHR-1 levels. Thus, a role of FHR-1 in IgAN pathogenesis is to compete with complement regulation by FH. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  6. A novel approach to isoindolo[2,1-a]indol-6-ones.

    PubMed

    Duncanson, Philip; Cheong, Yuen-Ki; Motevalli, Majid; Griffiths, D Vaughan

    2012-06-07

    A convenient route to isoindolo[2,1-a]indol-6-ones has been developed starting from the appropriate 2-(N-phthaloyl)benzoic acids. Formation of the acid chlorides with thionyl chloride followed by heating with triethyl phosphite in a suitable solvent resulted in a multistep reaction giving tetracyclic β-ketophosphonates that on reduction with sodium borohydride gave the required indolones in good overall yields. Analogous β-ketophosphonates were also prepared starting with N,N-(1,8-naphthaloyl)-2-aminobenzoic acid and 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoic acids although of these only the naphthaloyl product could be reduced with sodium borohydride without cleaving the amide bond in the ring system.

  7. The polymeric immunoglobulin receptor (secretory component) mediates transport of immune complexes across epithelial cells: a local defense function for IgA.

    PubMed Central

    Kaetzel, C S; Robinson, J K; Chintalacharuvu, K R; Vaerman, J P; Lamm, M E

    1991-01-01

    The polymeric immunoglobulin receptor (pIgR) on mucosal epithelial cells binds dimeric IgA (dIgA) on the basolateral surface and mediates transport of dIgA to the apical surface. Using Madin-Darby canine kidney epithelial cells stably transfected with pIgR cDNA, we found that soluble immune complexes (ICs) of 125I-labeled rat monoclonal antidinitrophenyl (DNP) dIgA (125I-dIgA) and DNP/biotin-bovine serum albumin were transported from the basolateral to the apical surface and then released. Monomeric IgA ICs were not transported, consistent with the specificity of pIgR for polymeric immunoglobulins. Essentially all the 125I-dIgA in apical culture supernatants was streptavidin precipitable, indicating that dIgA remained bound to antigen during transcytosis. While both dIgA and dIgA ICs bound pIgR with equal affinity (Kd approximately 8 nM), the number of high-affinity binding sites per cell was 2- to 3-fold greater for dIgA than for dIgA ICs. The extent of endocytosis of dIgA and dIgA ICs was correlated with the number of high-affinity binding sites. SDS/PAGE analysis of intracellular dIgA and dIgA ICs demonstrated that in both cases IgA remained undegraded during transport. The results suggest that the pathways of epithelial transcytosis of free dIgA and dIgA ICs are the same. Given the high population density of mucosal IgA plasma cells and the enormous surface area of pIgR-expressing mucosal epithelium, it is likely that significant local transcytosis of IgA ICs occurs in vivo. Such a process would allow direct elimination of IgA ICs at the mucosal sites where they are likely to form, thus providing an important defense function for IgA. Images PMID:1924341

  8. [Contribution of the detection of IgA antibodies to the laboratory diagnosis of mumps in the population with a high vaccination coverage].

    PubMed

    Limberková, R; Smíšková, D; Havlíčková, M; Herrmannová, K; Lexová, P; Malý, M

    2015-03-01

    Serological diagnosis of epidemic mumps can be difficult in vaccinated persons, particularly due to the absence of specific IgM antibodies. The aim was to find whether adding the detection of IgA antibodies to the currently used routine serological diagnosis of mumps (detection of IgM and IgG antibodies in an acute serum sample) would make the serological diagnosis of mumps more effective in a population with a high vaccination coverage. At the same time, ELISA kits for the detection of early IgA and IgM antibodies against the mumps virus were compared and statistical analysis of the results was performed. Sixty-four acute sera from patients with laboratory confirmed diagnosis of mumps were included in the study. Clinical specimens were collected at the onset of clinical symptoms. To test the sera, the MASTAZYME ELISA Mumps IgA kit (MAST DIAGNOSTICA, Germany) with the MASTSORB sorbent (RF and IgG) and Enzygnost Anti-Parotitis-Virus/IgM kit (Siemens, Germany) were used. A panel of 121 acute sera with no epidemiological link to mumps virus served as specificity controls for the IgA assay. The epidemiological data were derived from the EPIDAT system. The level of agreement was assessed using the McNemara test and Cohen's coefficient kappa. The Stata 9.2 software (Stata Corp LP, College Station, USA) was used for statistical analysis. The detection of IgA and IgM antibodies against the mumps virus yielded concordant results in 50/64 acute sera, 32 positive and 18 negative, i.e. an agreement of 78.12 %. Of the remaining 14 samples, 13 were only IgA positive and one was only IgM positive. The controls showed non-specific IgA positivity in 5/121 samples which indicates a 96% specificity. The absence of specific IgM antibodies against mumps virus is relatively often seen in vaccinated indivi-duals; nevertheless, the test is routinely used in patients with suspected active infection. The test for IgA antibodies, which is not routinely performed, significantly increased the

  9. Synthesis of IgM, IgG and IgA in rheumatoid arthritis.

    PubMed Central

    Poikonen, K; Oka, M; Möttönen, T; Jokinen, I; Arvilommi, H

    1982-01-01

    We studied the production of immunoglobulins by lymphocytes separated from the blood of 15 rheumatoid arthritis (RA) patients, of 12 patients suffering from other connective tissue diseases (CTD), and of 18 healthy controls. The production of IgM, IgG and IgA in pokeweed-mitogen-stimulated cultures was measured by counting the number of plaque-forming cells (PFC) and by determining the concentration of secreted immunoglobulins by means of an enzyme immunoassay. Synthesis of immunoglobulins, particularly IgM and IgG, was lower than in other CTD patients or controls. The IgM response of RA patients was 20% and 29% (PFC and Ig concentrations) that of the controls. The respective figures for IgG were 33% and 53% and for IgA 61% and 72%. PMID:6756322

  10. megaTALs: a rare-cleaving nuclease architecture for therapeutic genome engineering.

    PubMed

    Boissel, Sandrine; Jarjour, Jordan; Astrakhan, Alexander; Adey, Andrew; Gouble, Agnès; Duchateau, Philippe; Shendure, Jay; Stoddard, Barry L; Certo, Michael T; Baker, David; Scharenberg, Andrew M

    2014-02-01

    Rare-cleaving endonucleases have emerged as important tools for making targeted genome modifications. While multiple platforms are now available to generate reagents for research applications, each existing platform has significant limitations in one or more of three key properties necessary for therapeutic application: efficiency of cleavage at the desired target site, specificity of cleavage (i.e. rate of cleavage at 'off-target' sites), and efficient/facile means for delivery to desired target cells. Here, we describe the development of a single-chain rare-cleaving nuclease architecture, which we designate 'megaTAL', in which the DNA binding region of a transcription activator-like (TAL) effector is used to 'address' a site-specific meganuclease adjacent to a single desired genomic target site. This architecture allows the generation of extremely active and hyper-specific compact nucleases that are compatible with all current viral and nonviral cell delivery methods.

  11. Performance of an organic photodiode as an optical detector and its application to fluorometric flow-immunoassay for IgA.

    PubMed

    Miyake, Mayo; Nakajima, Hizuru; Hemmi, Akihide; Yahiro, Masayuki; Adachi, Chihaya; Soh, Nobuaki; Ishimatsu, Ryoichi; Nakano, Koji; Uchiyama, Katsumi; Imato, Toshihiko

    2012-07-15

    The performance of an organic thin film photodiode (OPD), fabricated from a hetero-junction comprised of two layers of C(60) and a phthalocyanine-Cu(II) complex was evaluated by detecting the chemiluminescence generated from the reaction of luminol with horseradish peroxidase in the presence of H(2)O(2), and the fluorescence from resorufin, as an optical detector. The photocurrent of the OPD was linear with respect to the power of light from a commercial LED. The sensitivity of the OPD was sufficient for detecting chemiluminescence with a power 0.1μW/cm(2). The OPD was successfully used in a flow-immunoassay for IgA, a marker of human stress, in which a sandwich immunoassay was carried out on the microchip and the fluorescence from resorufin, produced by the enzymatic reaction, was detected. The detection limits for resorufin and IgA were 5.0μM and 16ng/mL, respectively. The photosensitivity of the OPD remained relatively constant for a minimum of one year. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Effect of supplements: Probiotics and probiotic plus honey on blood cell counts and serum IgA in patients receiving pelvic radiotherapy.

    PubMed

    Mansouri-Tehrani, Hajar-Alsadat; Rabbani-Khorasgani, Mohammad; Hosseini, Sayyed Mohsen; Mokarian, Fariborz; Mahdavi, Hoda; Roayaei, Mahnaz

    2015-07-01

    Radiotherapy is frequently used in treatment approaches of pelvic malignancies. Nevertheless, it has some known systemic effects on blood cells and the immune system that possibly results in their susceptibility to infection. Probiotics are live microbial food ingredients that provide a health advantage to the consumer. Honey has prebiotic properties. The aim of this clinical trial was to investigate probable effects of probiotic or probiotics plus honey on blood cell counts and serum IgA levels in patients receiving pelvic radiotherapy. Sixty-seven adult patients with pelvic cancer were enrolled. Patients were randomized to receive either: (1) Probiotic capsules (including: Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium breve, Bifidobacterium longum, and Streptococcus thermophiles) (n = 22), (2) probiotic capsules plus honey (n = 21) or (3) placebo capsules (n = 24) all for 6 weeks. Blood and serum samples were collected for one week before radiotherapy and 24-72 h after the end of radiotherapy. White blood cells (WBC), red blood cells (RBC), platelet counts, and serum IgA level were not significantly changed in patients taking probiotic (alone or plus honey) during pelvic radiotherapy. The mean decrease in RBC count was 0.52, 0.18, and 0.23 × 10(6) cells/μL, WBC count was 2.3, 1.21, and 1.34 × 10(3) cells/μL and platelet count was, 57.6, 53.3, and 66.35 × 10(3) cells/μL for the probiotic, probiotic plus honey, and placebo groups, respectively. The mean decrease of serum IgA was 22.53, 29.94, and 40.73 mg/dL for the probiotic, probiotic plus honey, and placebo groups, respectively. The observed nonsignificant effect of probiotics may be in favor of local effects of this product in the gut rather than systemic effects, however, as a trend toward a benefit was indicated, further studies are necessary in order to extract effects of probiotics or probiotic plus honey on hematologic and

  13. Effect of supplements: Probiotics and probiotic plus honey on blood cell counts and serum IgA in patients receiving pelvic radiotherapy

    PubMed Central

    Mansouri-Tehrani, Hajar-Alsadat; Rabbani-Khorasgani, Mohammad; Hosseini, Sayyed Mohsen; Mokarian, Fariborz; Mahdavi, Hoda; Roayaei, Mahnaz

    2015-01-01

    Background: Radiotherapy is frequently used in treatment approaches of pelvic malignancies. Nevertheless, it has some known systemic effects on blood cells and the immune system that possibly results in their susceptibility to infection. Probiotics are live microbial food ingredients that provide a health advantage to the consumer. Honey has prebiotic properties. The aim of this clinical trial was to investigate probable effects of probiotic or probiotics plus honey on blood cell counts and serum IgA levels in patients receiving pelvic radiotherapy. Materials and Methods: Sixty-seven adult patients with pelvic cancer were enrolled. Patients were randomized to receive either: (1) Probiotic capsules (including: Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium breve, Bifidobacterium longum, and Streptococcus thermophiles) (n = 22), (2) probiotic capsules plus honey (n = 21) or (3) placebo capsules (n = 24) all for 6 weeks. Blood and serum samples were collected for one week before radiotherapy and 24-72 h after the end of radiotherapy. Results: White blood cells (WBC), red blood cells (RBC), platelet counts, and serum IgA level were not significantly changed in patients taking probiotic (alone or plus honey) during pelvic radiotherapy. The mean decrease in RBC count was 0.52, 0.18, and 0.23 × 106 cells/μL, WBC count was 2.3, 1.21, and 1.34 × 103 cells/μL and platelet count was, 57.6, 53.3, and 66.35 × 103 cells/μL for the probiotic, probiotic plus honey, and placebo groups, respectively. The mean decrease of serum IgA was 22.53, 29.94, and 40.73 mg/dL for the probiotic, probiotic plus honey, and placebo groups, respectively. Conclusion: The observed nonsignificant effect of probiotics may be in favor of local effects of this product in the gut rather than systemic effects, however, as a trend toward a benefit was indicated, further studies are necessary in order to extract effects of probiotics or

  14. The Mucosal Adjuvant Cholera Toxin B Instructs Non-Mucosal Dendritic Cells to Promote IgA Production Via Retinoic Acid and TGF-β

    PubMed Central

    Gloudemans, Anouk K.; Plantinga, Maud; Guilliams, Martin; Willart, Monique A.; Ozir-Fazalalikhan, Arifa; van der Ham, Alwin; Boon, Louis; Harris, Nicola L.; Hammad, Hamida; Hoogsteden, Henk C.; Yazdanbakhsh, Maria; Hendriks, Rudi W.

    2013-01-01

    It is currently unknown how mucosal adjuvants cause induction of secretory immunoglobulin A (IgA), and how T cell-dependent (TD) or -independent (TI) pathways might be involved. Mucosal dendritic cells (DCs) are the primary antigen presenting cells driving TI IgA synthesis, by producing a proliferation-inducing ligand (APRIL), B cell activating factor (BAFF), Retinoic Acid (RA), TGF-β or nitric oxide (NO). We hypothesized that the mucosal adjuvant Cholera Toxin subunit B (CTB) could imprint non-mucosal DCs to induce IgA synthesis, and studied the mechanism of its induction. In vitro, CTB-treated bone marrow derived DCs primed for IgA production by B cells without the help of T cells, yet required co-signaling by different Toll-like receptor (TLR) ligands acting via the MyD88 pathway. CTB-DC induced IgA production was blocked in vitro or in vivo when RA receptor antagonist, TGF-β signaling inhibitor or neutralizing anti-TGF-β was added, demonstrating the involvement of RA and TGF-β in promoting IgA responses. There was no major involvement for BAFF, APRIL or NO. This study highlights that synergism between CTB and MyD88-dependent TLR signals selectively imprints a TI IgA-inducing capacity in non-mucosal DCs, explaining how CTB acts as an IgA promoting adjuvant. PMID:23527272

  15. The mucosal adjuvant cholera toxin B instructs non-mucosal dendritic cells to promote IgA production via retinoic acid and TGF-β.

    PubMed

    Gloudemans, Anouk K; Plantinga, Maud; Guilliams, Martin; Willart, Monique A; Ozir-Fazalalikhan, Arifa; van der Ham, Alwin; Boon, Louis; Harris, Nicola L; Hammad, Hamida; Hoogsteden, Henk C; Yazdanbakhsh, Maria; Hendriks, Rudi W; Lambrecht, Bart N; Smits, Hermelijn H

    2013-01-01

    It is currently unknown how mucosal adjuvants cause induction of secretory immunoglobulin A (IgA), and how T cell-dependent (TD) or -independent (TI) pathways might be involved. Mucosal dendritic cells (DCs) are the primary antigen presenting cells driving TI IgA synthesis, by producing a proliferation-inducing ligand (APRIL), B cell activating factor (BAFF), Retinoic Acid (RA), TGF-β or nitric oxide (NO). We hypothesized that the mucosal adjuvant Cholera Toxin subunit B (CTB) could imprint non-mucosal DCs to induce IgA synthesis, and studied the mechanism of its induction. In vitro, CTB-treated bone marrow derived DCs primed for IgA production by B cells without the help of T cells, yet required co-signaling by different Toll-like receptor (TLR) ligands acting via the MyD88 pathway. CTB-DC induced IgA production was blocked in vitro or in vivo when RA receptor antagonist, TGF-β signaling inhibitor or neutralizing anti-TGF-β was added, demonstrating the involvement of RA and TGF-β in promoting IgA responses. There was no major involvement for BAFF, APRIL or NO. This study highlights that synergism between CTB and MyD88-dependent TLR signals selectively imprints a TI IgA-inducing capacity in non-mucosal DCs, explaining how CTB acts as an IgA promoting adjuvant.

  16. Microbiota regulate the ability of lung dendritic cells to induce IgA class-switch recombination and generate protective gastrointestinal immune responses

    PubMed Central

    Ruane, Darren; Chorny, Alejo; Lee, Haekyung; Faith, Jeremiah; Pandey, Gaurav; Shan, Meimei; Simchoni, Noa; Rahman, Adeeb; Garg, Aakash; Weinstein, Erica G.; Oropallo, Michael; Gaylord, Michelle; Ungaro, Ryan; Cunningham-Rundles, Charlotte; Alexandropoulos, Konstantina; Mucida, Daniel; Merad, Miriam; Cerutti, Andrea

    2016-01-01

    Protective immunoglobulin A (IgA) responses to oral antigens are usually orchestrated by gut dendritic cells (DCs). Here, we show that lung CD103+ and CD24+CD11b+ DCs induced IgA class-switch recombination (CSR) by activating B cells through T cell–dependent or –independent pathways. Compared with lung DCs (LDC), lung CD64+ macrophages had decreased expression of B cell activation genes and induced significantly less IgA production. Microbial stimuli, acting through Toll-like receptors, induced transforming growth factor-β (TGF-β) production by LDCs and exerted a profound influence on LDC-mediated IgA CSR. After intranasal immunization with inactive cholera toxin (CT), LDCs stimulated retinoic acid–dependent up-regulation of α4β7 and CCR9 gut-homing receptors on local IgA-expressing B cells. Migration of these B cells to the gut resulted in IgA-mediated protection against an oral challenge with active CT. However, in germ-free mice, the levels of LDC-induced, CT–specific IgA in the gut are significantly reduced. Herein, we demonstrate an unexpected role of the microbiota in modulating the protective efficacy of intranasal vaccination through their effect on the IgA class-switching function of LDCs. PMID:26712806

  17. Antithrombotic drug therapy for IgA nephropathy: a meta analysis of randomized controlled trials.

    PubMed

    Liu, Xiu-Juan; Geng, Yan-Qiu; Xin, Shao-Nan; Huang, Guo-Ming; Tu, Xiao-Wen; Ding, Zhong-Ru; Chen, Xiang-Mei

    2011-01-01

    Antithrombotic agents, including antiplatelet agents, anticoagulants and thrombolysis agents, have been widely used in the management of immunoglobulin A (IgA) nephropathy in Chinese and Japanese populations. To systematically evaluate the effects of antithrombotic agents for IgA nephropathy. Data sources consisted of MEDLINE, EMBASE, the Cochrane Library, Chinese Biomedical Literature Database (CBM), Chinese Science and Technology Periodicals Databases (CNKI) and Japana Centra Revuo Medicina (http://www.jamas.gr.jp) up to April 5, 2011. The quality of the studies was evaluated from the intention to treat analysis and allocation concealment, as well as by the Jadad method. Meta-analyses were performed on the outcomes of proteinuria and renal function. Six articles met the predetermined inclusion criteria. Antithrombotic agents showed statistically significant effects on proteinuria (p<0.0001) but not on the protection of renal function (p=0.07). The pooled risk ratio for proteinuria was 0.53, [95% confidence intervals (CI): 0.41-0.68; I(2)=0%] and for renal function it was 0.42 (95% CI 0.17-1.06; I(2)=72%). Subgroup analysis showed that dipyridamole was beneficial for proteinuria (p=0.0003) but had no significant effects on protecting renal function. Urokinase had statistically significant effects both on the reduction of proteinuria (p=0.0005) and protecting renal function (p<0.00001) when compared with the control group. Antithrombotic agents had statistically significant effects on the reduction of proteinuria but not on the protection of renal function in patients with IgAN. Urokinase had statistically significant effects both on the reduction of proteinuria and on protecting renal function. Urokinase was shown to be a promising medication and should be investigated further.

  18. Attenuation of doxorubicin-induced cardiotoxicity by esculetin through modulation of Bmi-1 expression.

    PubMed

    Xu, Fan; Li, Xiao; Liu, Lanfang; Xiao, Xu; Zhang, Li; Zhang, Shenglin; Lin, Pingping; Wang, Xiaojie; Wang, Yongwei; Li, Qingshan

    2017-09-01

    The protective effects and mechanisms of esculetin on doxorubicin (DOX)-induced injury of H9c2 cells were investigated. H9c2 cells were cultured and the logarithmic growth phase of the cells was divided into a control group, a DOX group and an esculetin + DOX group. Cell viability was detected by MTT assay. Annexin V-PI (AV-PI) double staining flow cytometry was carried out to detect cell apoptosis. Intracellular reactive oxygen species (ROS) were detected by flow cytometry. Transmission electron microscope (TEM) was used to evaluate cell ultrastructure. Cleaved caspase-3, cleaved PARP, Bcl-2, Bid and Bmi-1 proteins levels were investigated by western blot analysis. Bmi-1 siRNA was used to detect the role of Bmi-1 in the protective effects of esculetin against DOX-induced toxicity in H9c2 cells. The MTT and AV-PI double staining results showed that esculetin significantly increased H9c2 cell viability. Compared with the control group, the levels of cleaved caspase-3, cleaved PARP, Bid and ROS levels were significantly decreased, but the expression of Bcl-2 and Bmi-1 were significantly increased in the esculetin + DOX group. TEM showed that the cell structure of the mitochondria was protected by esculetin. The results of Bmi-1 siRNA showed that esculetin could protect DOX-induced cardiotoxicity by modulating Bmi-1 expression. Esculetin can protect DOX-induced cardiotoxicity and the effects may be attributable to modulation of Bmi-1 expression, provoking intracellular ROS accumulation, protecting the structure of mitochondria and reducing cell apoptosis.

  19. Anti-GP2 IgA autoantibodies are associated with poor survival and cholangiocarcinoma in primary sclerosing cholangitis.

    PubMed

    Jendrek, Sebastian Torben; Gotthardt, Daniel; Nitzsche, Thomas; Widmann, Laila; Korf, Tobias; Michaels, Maike Anna; Weiss, Karl-Heinz; Liaskou, Evaggelia; Vesterhus, Mette; Karlsen, Tom Hemming; Mindorf, Swantje; Schemmer, Peter; Bär, Florian; Teegen, Bianca; Schröder, Torsten; Ehlers, Marc; Hammers, Christoph Matthias; Komorowski, Lars; Lehnert, Hendrik; Fellermann, Klaus; Derer, Stefanie; Hov, Johannes Roksund; Sina, Christian

    2017-01-01

    Pancreatic autoantibodies (PABs), comprising antibodies against glycoprotein 2 (anti-GP2), are typically associated with complicated phenotypes in Crohn's disease, but have also been observed with variable frequencies in patients with UC. In a previous study, we observed a high frequency of primary sclerosing cholangitis (PSC) in patients with anti-GP2-positive UC. We therefore aimed to characterise the role of anti-GP2 in PSC. In an evaluation phase, sera from 138 well-characterised Norwegian patients with PSC were compared with healthy controls (n=52), and patients with UC without PSC (n=62) for the presence of PABs by indirect immunofluorescence. Further, 180 German patients with PSC served as a validation cohort together with 56 cases of cholangiocarcinoma without PSC, 20 of secondary sclerosing cholangitis (SSC) and 18 of autoimmune hepatitis. Anti-GP2 IgA specifically occurred at considerable rates in large bile duct diseases (cholangiocarcinoma=36%, PSC and SSC about 50%). In PSC, anti-GP2 IgA consistently identified patients with poor survival during follow-up (Norwegian/German cohort: p Log Rank=0.016/0.018). Anti-GP2 IgA was associated with the development of cholangiocarcinoma in both PSC cohorts, yielding an overall OR of cholangiocarcinoma in patients with anti-GP2 IgA-positive PSC of 5.0 (p=0.001). Importantly, this association remained independent of disease duration, bilirubin level and age. Anti-GP2 IgA can be hypothesised as a novel marker in large bile duct diseases. In particular, in PSC, anti-GP2 IgA identified a subgroup of patients with severe phenotype and poor survival due to cholangiocarcinoma. Anti-GP2 IgA may therefore be a clinically valuable tool for risk stratification in PSC. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. The Salivary IgA Flow Rate Is Increased by High Concentrations of Short-Chain Fatty Acids in the Cecum of Rats Ingesting Fructooligosaccharides

    PubMed Central

    Yamamoto, Yuko; Takahahi, Toru; To, Masahiro; Nakagawa, Yusuke; Hayashi, Takashi; Shimizu, Tomoko; Kamata, Yohei; Saruta, Juri; Tsukinoki, Keiichi

    2016-01-01

    Salivary immunoglobulin A (IgA) serves as a major effector in mucosal immunity by preventing submucosal invasion of pathogens. However, the mechanism by which consumption of fermentable fibers increases IgA in saliva was not fully elucidated. This study investigated the effects of fructooligosaccharides (FOS) intake and time after feeding on IgA levels in the saliva and cecal digesta and on the concentration of short-chain fatty acids (SCFA) in the cecum in rats. Five-week-old rats were fed a fiber-free diet or a diet with 50 g/kg FOS for zero, one, four, and eight weeks. Ingestion of FOS at one and eight weeks led to a higher IgA flow rate of saliva per weight of submandibular gland tissue (p < 0.05), which positively correlated with the concentration of SCFA in the cecal digesta (rs = 0.86, p = 0.0006, n = 12), but showed no correlation with the concentration of IgA in the cecal digesta (rs = 0.15, p = 0.3, n = 48). These results suggested that ingestion of FOS increased salivary IgA secretion through high levels of SCFA in the large intestine, which was produced by fermentation of FOS. Thus, continuously ingesting FOS for more than one week could increase secretion of salivary IgA. PMID:27548207

  1. Specific recognition of hydatid cyst antigens by serum IgG, IgE, and IgA using western blot.

    PubMed

    Sbihi, Y; Janssen, D; Osuna, A

    1997-01-01

    Diagnosis of hydatid disease in humans relies on the detection of specific antibodies against antigens of the metacestode from Echinococcus granulosus. The specificity and sensitivity of current immunological techniques based on specific serum IgG rely on the way antigens are purified. We used Western immunoblotting to detect specific IgG, IgE, and IgA antibodies in serum from patients with hydatid disease using either crude antigen preparations (total hydatid fluid), purified fractions enriched in Antigens 5 and B, and glycoproteins from hydatid fluid. Depending on whether crude HF or purified antigen fractions were used, IgG and IgE recognized specifically low-to-medium MW bands between 12 and 42 kDa. IgA recognized specifically 110 kDa band in crude hydatid fluid and in the glycoprotein fraction of hydatid fluid, and a 42 kDa band in all antigen samples used. Besides the advantage of detecting specific IgA in crude hydatid fluid, these results offer the possibility of simplifying future immunological tests if specific secretory IgA can be similarly detected.

  2. Production and characterization of soluble human TNFRI-Fc and human HO-1(HMOX1) transgenic pigs by using the F2A peptide.

    PubMed

    Park, Sol Ji; Cho, Bumrae; Koo, Ok Jae; Kim, Hwajung; Kang, Jung Taek; Hurh, Sunghoon; Kim, Su Jin; Yeom, Hye Jung; Moon, Joonho; Lee, Eun Mi; Choi, Ji Yei; Hong, Ju Ho; Jang, Goo; Hwang, Joing-Ik; Yang, Jaeseok; Lee, Byeong Chun; Ahn, Curie

    2014-06-01

    Generation of transgenic pigs for xenotransplantation is one of the most promising technologies for resolving organ shortages. Human heme oxygenase-1 (hHO-1/HMOX1) can protect transplanted organs by its strong anti-oxidative, anti-apoptotic, and anti-inflammatory effects. Soluble human TNFRI-Fc (shTNFRI-Fc) can inhibit the binding of human TNF-α (hTNF-α) to TNF receptors on porcine cells, and thereby, prevent hTNF-α-mediated inflammation and apoptosis. Herein, we successfully generated shTNFRI-Fc-F2A-HA-hHO-1 transgenic (TG) pigs expressing both shTNFRI-Fc and hemagglutinin-tagged-human heme oxygenase-1 (HA-hHO-1) by using an F2A self-cleaving peptide. shTNFRI-Fc and HA-hHO-1 transgenes containing the F2A peptide were constructed under the control of the CAG promoter. Transgene insertion and copy number in the genome of transgenic pigs was confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Expressions of shTNFRI-Fc and HA-hHO-1 in TG pigs were confirmed using PCR, RT-PCR, western blot, ELISA, and immunohistochemistry. shTNFRI-Fc and HA-hHO-1 were expressed in various organs, including the heart, lung, and spleen. ELISA assays detected shTNFRI-Fc in the sera of TG pigs. For functional analysis, fibroblasts isolated from a shTNFRI-Fc-F2A-HA-hHO-1 TG pig (i.e., #14; 1 × 10(5) cells) were cultured with hTNF-α (20 ng/mL) and cycloheximide (10 μg/mL). The viability of shTNFRI-Fc-F2A-HA-hHO-1 TG pig fibroblasts was significantly higher than that of the wild type (wild type vs. shTNFRI-Fc-F2A-HA-hHO-1 TG at 24 h, 31.6 ± 3.2 vs. 60.4 ± 8.3 %, respectively; p < 0.05). Caspase-3/-7 activity of the shTNFRI-Fc-F2A-HA-hHO-1 TG pig fibroblasts was lower than that of the wild type pig fibroblasts (wild type vs. shTNFRI-Fc-F2A-HA-hHO-1 TG at 12 h, 812,452 ± 113,078 RLU vs. 88,240 ± 10,438 RLU, respectively; p < 0.05). These results show that shTNFRI-Fc and HA-hHO-1 TG pigs generated by the F2A self-cleaving peptide express both sh

  3. Salivary IgA against sporozoite-specific embryogenesis-related protein (TgERP) in the study of horizontally transmitted toxoplasmosis via T. gondii oocysts in endemic settings

    USDA-ARS?s Scientific Manuscript database

    The prevalence of toxoplasmosis was investigated in endemic settings in Brazil, and calculated by measuring antibodies in two ELISA systems: 1) IgG and IgM from sera tested by commercial conventional ELISA, and 2) IgA, from saliva, and IgG from sera samples tested against a sporozoite-specific prote...

  4. Liver membrane antibodies in alcoholic liver disease: 1. prevalence and immunoglobulin class.

    PubMed Central

    Burt, A D; Anthony, R S; Hislop, W S; Bouchier, I A; MacSween, R N

    1982-01-01

    Using an indirect immunofluorescence technique liver membrane antibodies of IgG and IgA class have been demonstrated in a statistically significant proportion of sera from patients with alcoholic hepatitis and alcoholic cirrhosis. IgG and IgA class antibodies were found respectively in 23 and 25% of 48 patients with alcoholic hepatitis, in 27 and 33% of 84 with active cirrhosis, and 67 and 58% of 12 with inactive cirrhosis. These results provide evidence of a humoral immune response in alcoholic liver disease which is directed against, as yet undefined, liver-cell membrane antigens. Images Fig. 1 PMID:7040177

  5. ISOLATION OF RABBIT IGA ANTIHAPTEN ANTIBODY AND DEMONSTRATION OF SKIN-SENSITIZING ACTIVITY IN HOMOLOGOUS SKIN

    PubMed Central

    Onoue, Kaoru; Yagi, Yasuo; Pressman, David

    1966-01-01

    Multiple antibody components of rabbit antisera against p-azobenzenearsonate (Rp) were studied with respect to their globulin nature and skin-sensitizing activity. IgA antibody was characterized by isolating two IgA-rich fractions from a specifically purified antibody preparation. Examination of these fractions showed that IgA antibodies existed in two molecular forms, one with a sedimentation constant of 7S and the other 9S. Skin-sensitizing activity was examined by a P-K type test and a PCA test with Rp-rabbit serum albumin in homologous (rabbit) species. Only the 7S but not 9S IgA antibody sensitized rabbit skin. IgM antibody showed no activity and IgG antibody showed very low activity. In contrast, only IgG antibody was active in the P-K type test to sensitize a heterologous species (guinea pig). None of the antibodies of other classes showed sensitizing activity in heterologous skin. The 7S IgA antibody lost its sensitizing activity upon reduction and alkylation, although no change in its molecular size could be observed. The loss of sensitizing activity was not due to the destruction of antigen-binding activity since the treated 7S IgA antibody retained this activity as shown by radioimmunoelectrophoresis and by binding to the specific immunoadsorbent. The 9S IgA antibody was more resistant to these treatments than the IgM antibody and showed no indication of dissociation. The treated 9S IgA also retained antigen-binding activity. Both the P-K type and PCA reactions were considerably stronger when the interval between injections of antibody and antigen was 24 hr rather than 4 to 5 hr. PMID:4159250

  6. Protein-energy malnutrition alters IgA responses to rotavirus vaccination and infection but does not impair vaccine efficacy in mice

    PubMed Central

    Maier, Elizabeth A.; Weage, Kristina J.; Guedes, Marjorie M; Denson, Lee A.; McNeal, Monica M.; Bernstein, David I.; Moore, Sean R.

    2013-01-01

    Background Conflicting evidence links malnutrition to the reduced efficacy of rotavirus vaccines in developing countries, where diarrhea and undernutrition remain leading causes of child deaths. Here, we adapted mouse models of rotavirus vaccination (rhesus rotavirus, RRV), rotavirus infection (EDIM), and protein-energy malnutrition (PEM) to test the hypothesis that undernutrition reduces rotavirus vaccine immunogenicity and efficacy. Methods We randomized wild type Balb/C dams with 3-day-old pups to a control diet (CD) or an isocaloric, multideficient regional basic diet (RBD) that produces PEM. At 3 weeks of age, we weaned CD and RBD pups to their dams’ diet and subrandomized weanlings to receive a single dose of either live oral rotavirus vaccine (RRV) or PBS. At 6 weeks of age, we orally challenged all groups with murine rotavirus (EDIM). Serum and stool specimens were collected before and after RRV and EDIM administration to measure viral shedding and antibody responses by ELISA. Results RBD pups and weanlings exhibited significant failure to thrive compared to age-matched CD mice (P<.0001). RRV vaccination induced higher levels of serum anti-RV IgA responses in RBD vs. CD mice (P<.0001). Vaccination protected CD and RBD mice equally against EDIM infection, as measured by viral shedding. In unvaccinated RBD mice, EDIM shedding peaked 1 day earlier (P<.05), however we detected no effects of undernutrition on viral clearance nor of infection on bodyweight. EDIM infection provoked higher anti-RV serum IgA levels in RBD vs. CD mice, regardless of vaccination (P<.0001). Last, RRV vaccination mitigated stool IgA responses to EDIM more in CD vs. RBD mice (P<.0001). Conclusions Despite modulated IgA responses to vaccination and infection, undernutrition does not impair rotavirus vaccine efficacy nor exacerbate infection in this mouse model of protein-energy malnutrition. Alternative models are needed to elucidate host-pathogen factors undermining rotavirus vaccine

  7. Protein-energy malnutrition alters IgA responses to rotavirus vaccination and infection but does not impair vaccine efficacy in mice.

    PubMed

    Maier, Elizabeth A; Weage, Kristina J; Guedes, Marjorie M; Denson, Lee A; McNeal, Monica M; Bernstein, David I; Moore, Sean R

    2013-12-17

    Conflicting evidence links malnutrition to the reduced efficacy of rotavirus vaccines in developing countries, where diarrhea and undernutrition remain leading causes of child deaths. Here, we adapted mouse models of rotavirus vaccination (rhesus rotavirus, RRV), rotavirus infection (EDIM), and protein-energy malnutrition (PEM) to test the hypothesis that undernutrition reduces rotavirus vaccine immunogenicity and efficacy. We randomized wild type Balb/C dams with 3-day-old pups to a control diet (CD) or an isocaloric, multideficient regional basic diet (RBD) that produces PEM. At 3 weeks of age, we weaned CD and RBD pups to their dams' diet and subrandomized weanlings to receive a single dose of either live oral rotavirus vaccine (RRV) or PBS. At 6 weeks of age, we orally challenged all groups with murine rotavirus (EDIM). Serum and stool specimens were collected before and after RRV and EDIM administration to measure viral shedding and antibody responses by ELISA. RBD pups and weanlings exhibited significant failure to thrive compared to age-matched CD mice (P<.0001). RRV vaccination induced higher levels of serum anti-RV IgA responses in RBD vs. CD mice (P<.0001). Vaccination protected CD and RBD mice equally against EDIM infection, as measured by viral shedding. In unvaccinated RBD mice, EDIM shedding peaked 1 day earlier (P<.05), however we detected no effects of undernutrition on viral clearance nor of infection on bodyweight. EDIM infection provoked higher anti-RV serum IgA levels in RBD vs. CD mice, regardless of vaccination (P<.0001). Last, RRV vaccination mitigated stool IgA responses to EDIM more in CD vs. RBD mice (P<.0001). Despite modulated IgA responses to vaccination and infection, undernutrition does not impair rotavirus vaccine efficacy nor exacerbate infection in this mouse model of protein-energy malnutrition. Alternative models are needed to elucidate host-pathogen factors undermining rotavirus vaccine effectiveness in high-risk global settings

  8. [Identification of cyst and trophozoite antigens from Colombian Giardia duodenalis isolates recognized by IgA].

    PubMed

    Olmos, Rosana Natalia; Duque, Sofía; López, Myriam Consuelo; Arévalo, Adriana; Guerrero, Rafael; Velandia, Martha Patricia; Nicholls, Ruben Santiago

    2003-09-01

    Little is known about the role of IgA in the immune response against Giardia duodenalis infection. The current study identified the antigens of Colombian G. duodenalis isolates which stimulate the production of IgA anti-G. dudoenalis. Cyst and trophozoite stage proteins were separated by SDS-PAGE and their antigenicity was determined by Western blot. Without 2-mercapto ethanol (2-ME), the protein profile of the cyst stage showed 24 proteins within a molecular weight range of 23-270 kDa; with 2-ME, 35 polypeptides ranging from 22 to 241 kDa were distinguished. The trophozoite stage protein profile without 2-ME was formed by 16 proteins within the range of 24-270 kDa; with 2-ME, 45 proteins were present between 18 and 241 kDa. The identification of 20 and 29 antigens from the cyst and trophozoite stage, respectively, suggested that G. duodenalis stimulates a specific humoral immune response in the human host. The antigens of 31, 57, 110, 133, and 170 kDa recognized by anti-G duodenalis IgA in both cysts and trophozoites corresponded with G. duodenalis isolates from other geographic regions, whereas those of 35, 38, 43, 45, 49, 52, 60, 62, 65, 72, 82, 99, 145, 155, and 185 kDa seemed specific to Colombian isolates. This indicated that antigens of 57, 65, 145, and 170 kDa, recognized by anti-G. duodenalis IgA antibodies in cysts (with frequencies between 82% and 96%) and trophozoites (with frequencies between 86% and 97%) can be considered identification markers for G. duodenalis infections.

  9. Protein tyrosine phosphatase 1B (PTP1B) is required for cardiac lineage differentiation of mouse embryonic stem cells.

    PubMed

    Eshkiki, Zahra Shokati; Ghahremani, Mohammad Hossein; Shabani, Parisa; Firuzjaee, Sattar Gorgani; Sadeghi, Asie; Ghanbarian, Hossein; Meshkani, Reza

    2017-01-01

    Protein tyrosine phosphatase 1B (PTP1B) has been shown to regulate multiple cellular events such as differentiation, cell growth, and proliferation; however, the role of PTP1B in differentiation of embryonic stem (ES) cells into cardiomyocytes remains unexplored. In the present study, we investigated the effects of PTP1B inhibition on differentiation of ES cells into cardiomyocytes. PTP1B mRNA and protein levels were increased during the differentiation of ES cells into cardiomyocytes. Accordingly, a stable ES cell line expressing PTP1B shRNA was established. In vitro, the number and size of spontaneously beating embryoid bodies were significantly decreased in PTP1B-knockdown cells, compared with the control cells. Decreased expression of cardiac-specific markers Nkx2-5, MHC-α, cTnT, and CX43, as assessed by real-time PCR analysis, was further confirmed by immunocytochemistry of the markers. The results also showed that PTP1B inhibition induced apoptosis in both differentiated and undifferentiated ES cells, as presented by increasing the level of cleaved caspase-3, cytochrome C, and cleaved PARP. Further analyses revealed that PTP1B inhibition did not change proliferation and pluripotency of undifferentiated ES cells. Taken together, the data presented here suggest that PTP1B is essential for proper differentiation of ES cells into cardiomyocytes.

  10. Rapamycin Enhances Repressed Autophagy and Attenuates Aggressive Progression in a Rat Model of IgA Nephropathy.

    PubMed

    Liu, Di; Liu, Yexin; Chen, Guochun; He, Liyu; Tang, Chengyuan; Wang, Chang; Yang, Danyi; Li, Huiqiong; Dong, Zheng; Liu, Hong

    2017-01-01

    IgA nephropathy (IgAN) has been considered to be the most frequent form of primary glomerulonephritis that occurs worldwide with a variety of factors involved in its occurrence and development. The impact of autophagy in IgAN, however, remains partially unclear. This study was designed to investigate the effects of rapamycin in an IgAN model. After establishing an IgAN rat model, SD rats were divided into 4 groups: control, control + rapamycin, IgAN, IgAN + rapamycin. Proteinuria and the pathological changes and the level of autophagy of kidney were texted. Identify the expression of phosphorylation and total mammalian target of rapamycin (mTOR) and s6k1 as well as cyclin D1 in the kidney of rats through Western blot and immunohistochemistry. With rapamycin treatment, we observed a significant reduction in the progression of proteinuria as well as alleviation of pathological lesions in IgAN rats. Besides, autophagy was inhibited, while the mTOR/S6k1 pathway was activated and expression of cyclin D1 was increased in IgAN. Rapamycin treatment increased autophagy and decreased the expression of cyclin D1. These results may suggest that mTOR-mediated autophagy inhibition may result in mesangial cell proliferation in IgAN. © 2017 S. Karger AG, Basel.

  11. Pulmonary α-1,3-Glucan-Specific IgA-Secreting B Cells Suppress the Development of Cockroach Allergy1

    PubMed Central

    Patel, Preeyam S.; King, R. Glenn; Kearney, John F.

    2016-01-01

    There is a higher incidence of allergic conditions among children living in industrialized countries than those in developing regions. One explanation for this is reduced neonatal exposure to microbes and the consequent lack of immune stimulation. Sensitivity to cockroach allergen is highly correlated with the development of severe asthma. In this study, we determined that an antibody to microbial α-1,3-glucan binds an Enterobacter species and cockroach allergen. Neonatal, but not adult, mice immunized with this α-1,3-glucan-bearing Enterobacter (MK7) are protected against cockroach allergy. Following exposure to cockroach allergen, α-1,3-glucan-specific IgA-secreting cells are present in the lungs of mice immunized with MK7 as neonates, but not in the lungs of those immunized as adults. Mice that are unable to generate anti-α-1,3-glucan IgA antibodies were immunized with MK7 as neonates and were no longer protected against cockroach allergy. Thus, neonatal, but not adult, exposure to α-1,3-glucan results in suppressed development of cockroach allergy via pulmonary α-1,3-glucan-specific IgA-secreting cells. PMID:27581173

  12. The caspase-generated cleavage product of Ets-1 p51 and Ets-1 p27, Cp17, induces apoptosis.

    PubMed

    Choul-Li, Souhaila; Tulasne, David; Aumercier, Marc

    2016-11-04

    The transcription factor Ets-1 is involved in various physiological processes and invasive pathologies. Human Ets-1 exists under three isoforms: p51, the predominant full-length isoform, p42 and p27, shorter alternatively spliced isoforms. We have previously demonstrated that Ets-1 p51, but not the spliced variant Ets-1 p42, is processed by caspases in vitro and during apoptosis. However, the caspase cleavage of the second spliced variant Ets-1 p27 remains to investigate. In the present study, we demonstrate that Ets-1 p27 is a cleavage substrate of caspases. We show that Ets-1 p27 is processed in vitro by caspase-3, resulting in three C-terminal fragments Cp20, Cp17 and Cp14. Similarly, Ets-1 p27 was cleaved during apoptotic cell death induced by anisomycin, producing fragments consistent with those observed in in vitro cleavage assay. These fragments are generated by cleavage at three sites located in the exon VII-encoded region of Ets-1 p27. As a functional consequences, Cp17 fragment, the major cleavage product generated during apoptosis, induced itself apoptosis when transfected into cells. Our results show that Ets-1 p27 is cleaved in the same manner as Ets-1 p51 within the exon VII-encoded region, thus generating a stable C-terminal fragment that induces cell death by initiating apoptosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Different Pathological Roles of Toll-Like Receptor 9 on Mucosal B Cells and Dendritic Cells in Murine IgA Nephropathy

    PubMed Central

    Kajiyama, Tadahiro; Suzuki, Yusuke; Kihara, Masao; Suzuki, Hitoshi; Horikoshi, Satoshi; Tomino, Yasuhiko

    2011-01-01

    Although pathogenesis of IgA nephropathy (IgAN) is still obscure, pathological contribution of mucosal immunity including production of nephritogenic IgA and IgA immune complex (IC) has been discussed. We have reported that mucosal toll-like receptor (TLR)-9 is involved in the pathogenesis of human and murine IgAN. However, cell-type expressing TLR9 in mucosa remains unclear. To address this, we nasally challenged cell-specific CpG DNA ((i): dendritic cell: (DC), (ii): B cell, (iii): both), known as ligand for TLR9, to IgAN prone mice and analyzed disease phenotype of each group. After 8 times of the weekly administration, every group showed deterioration of glomerular damage. However, CpG-A-group showed clear extension of mesangial proliferative lesions with increase of serum IgA-IgG2a IC and its glomerular depositions, while CpG-B-group showed extent of glomerular sclerotic lesions with increase of serum and glomerular IgA and M2 macrophage infiltration. Present results indicate that mucosal TLR9 on B cells and DC may differently contribute to the progression of this disease via induction of nephritogenic IgA or IgA-IgG IC, respectively. This picture is suggestive for the pathological difference between child and adult IgAN. PMID:21765852

  14. Corticosteroids in IgA Nephropathy: A Retrospective Analysis from the VALIGA Study

    PubMed Central

    Tesar, Vladimir; Troyanov, Stéphan; Bellur, Shubha; Verhave, Jacobien C.; Cook, H. Terence; Feehally, John; Roberts, Ian S.D.; Cattran, Daniel

    2015-01-01

    Current guidelines suggest treatment with corticosteroids (CS) in IgA nephropathy (IgAN) when proteinuria is persistently ≥1 g/d despite 3–6 months of supportive care and when eGFR is >50 ml/min per 1.73 m2. Whether the benefits of this treatment extend to patients with an eGFR≤50 ml/min per 1.73 m2, other levels of proteinuria, or different renal pathologic lesions remains unknown. We retrospectively studied 1147 patients with IgAN from the European Validation Study of the Oxford Classification of IgAN (VALIGA) cohort classified according to the Oxford-MEST classification and medication used, with details of duration but not dosing. Overall, 46% of patients received immunosuppression, of which 98% received CS. Treated individuals presented with greater clinical and pathologic risk factors of progression. They also received more antihypertensive medication, and a greater proportion received renin angiotensin system blockade (RASB) compared with individuals without immunosuppressive therapy. Immunosuppression was associated with a significant reduction in proteinuria, a slower rate of renal function decline, and greater renal survival. Using a propensity score, we matched 184 subjects who received CS and RASB to 184 patients with a similar risk profile of progression who received only RASB. Within this group, CS reduced proteinuria and the rate of renal function decline and increased renal survival. These benefits extended to those with an eGFR≤50 ml/min per 1.73 m2, and the benefits increased proportionally with the level of proteinuria. Thus, CS reduced the risk of progression regardless of initial eGFR and in direct proportion to the extent of proteinuria in this cohort. PMID:25677392

  15. Non-classical forms of pemphigus: pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus and IgG/IgA pemphigus*

    PubMed Central

    Porro, Adriana Maria; Caetano, Livia de Vasconcelos Nasser; Maehara, Laura de Sena Nogueira; Enokihara, Milvia Maria dos Santos

    2014-01-01

    The pemphigus group comprises the autoimmune intraepidermal blistering diseases classically divided into two major types: pemphigus vulgaris and pemphigus foliaceous. Pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus and IgG/IgA pemphigus are rarer forms that present some clinical, histological and immunopathological characteristics that are different from the classical types. These are reviewed in this article. Future research may help definitively to locate the position of these forms in the pemphigus group, especially with regard to pemphigus herpetiformis and the IgG/ IgA pemphigus. PMID:24626654

  16. Hyperglycemia-induced Bcl-2/Bax-mediated apoptosis of Schwann cells via mTORC1/S6K1 inhibition in diabetic peripheral neuropathy.

    PubMed

    Zhu, Lin; Hao, Jun; Cheng, Meijuan; Zhang, Cuihong; Huo, Chunxiu; Liu, Yaping; Du, Wei; Zhang, Xianghong

    2018-06-15

    Schwann cell apoptosis is one of the characteristics of diabetic peripheral neuropathy (DPN). The mammalian target of rapamycin (mTOR) is a multifunctional signaling pathway that regulates cell apoptosis in various types of tissues and cells. To investigate whether the mTOR pathway is involved in cell apoptosis in the Schwann cells of DPN, diabetic mice and rat Schwann cells (RSC96) were chosen to detect phospho-mTOR (Ser 2448), phospho-S6K1 (Thr 389), phospho-4EBP1 (Thr 37/46), Bcl-2, Bax and cleaved caspase-3 by diverse pathological and biological techniques. The results showed that phospho-mTOR (Ser 2448) was decreased in the sciatic nerves of diabetic mice, concomitant with decreased Bcl-2, increased Bax, cleaved caspase-3 and cell apoptosis. In addition, high glucose treatment for 72 h caused a 35.95% decrease in the phospho-mTOR (Ser 2448)/mTOR ratio, a 65.50% decrease in the phospho-S6K1 (Thr 389)/S6K1 ratio, a 3.67-fold increase in the Bax/Bcl-2 ratio and a 1.47-fold increase in the cleaved caspase-3/caspase-3 ratio. Furthermore, mTORC1 inhibition, rather than mTORC2 inhibition, resulted in mitochondrial controlled apoptosis in RSC96 cells by silencing RAPTOR or RICTOR. Again, suppression of the mTORC1 pathway by a chemical inhibitor led to mitochondrial controlled apoptosis in cultured RSC96 cells in vitro. By contrast, activation of the mTORC1 pathway with MHY1485 prevented decreased phospho-S6K1 (Thr 389) levels caused by high glucose and cell apoptosis. Additionally, constitutive activation of S6K1 avoided high glucose-induced cell apoptosis in RSC96 cells. In summary, our findings suggest that activating mTORC1/S6K1 signaling in Schwann cells may be a promising strategy for the prevention and treatment of DPN. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Deleted in malignant brain tumors-1 protein (DMBT1): a pattern recognition receptor with multiple binding sites.

    PubMed

    Ligtenberg, Antoon J M; Karlsson, Niclas G; Veerman, Enno C I

    2010-01-01

    Deleted in Malignant Brain Tumors-1 protein (DMBT1), salivary agglutinin (DMBT1(SAG)), and lung glycoprotein-340 (DMBT1(GP340)) are three names for glycoproteins encoded by the same DMBT1 gene. All these proteins belong to the scavenger receptor cysteine-rich (SRCR) superfamily of proteins: a superfamily of secreted or membrane-bound proteins with SRCR domains that are highly conserved down to sponges, the most ancient metazoa. In addition to SRCR domains, all DMBT1s contain two CUB domains and one zona pellucida domain. The SRCR domains play a role in the function of DMBT1s, which is the binding of a broad range of pathogens including cariogenic streptococci, Helicobacter pylori and HIV. Mucosal defense proteins like IgA, surfactant proteins and lactoferrin also bind to DMBT1s through their SRCR domains. The binding motif on the SRCR domains comprises an 11-mer peptide in which a few amino acids are essential for binding (GRVEVLYRGSW). Adjacent to each individual SRCR domain are glycosylation domains, where the attached carbohydrate chains play a role in the binding of influenza A virus and Helicobacter pylori. The composition of the carbohydrate chains is not only donor specific, but also varies between different organs. These data demonstrate a role for DMBT1s as pattern recognition molecules containing various peptide and carbohydrate binding motifs.

  18. The secretory IgA system of lung secretions in chronic obstructive bronchitis: comparison of sputum with secretions obtained during fibreoptic bronchoscopy.

    PubMed Central

    Wiggins, J; Hill, S L; Stockley, R A

    1984-01-01

    The constituents of the secretory immunoglobulin A system (dimeric IgA, total secretory component and free secretory component) were measured in sputum sol phase, tracheal aspirates, and bronchoalveolar lavage fluids from 15 patients undergoing fibreoptic bronchoscopy. All of the proteins showed a progressive decrease in concentration from sputum to the bronchoalveolar lavage fluids (2p less than 0.001). Standardisation of samples by means of protein concentration ratios showed that all secretions were generally similar in respect of their secretory IgA profiles, although major differences remained in some individual patients. The between patient variability of the results was generally reduced by the use of protein concentration ratios, allowing closer comparison between subjects. When the secretion albumin concentration was used as a standard, however, it increased the variability of the sputum sol phase IgA components (2p less than 0.01), whereas it decreased the variability of the IgA components in the bronchoalveolar lavage fluid (2p less than 0.05). The role of albumin as a standard protein for assessing the secretory IgA system in lung secretions remains uncertain. PMID:6463931

  19. Par3 and aPKC regulate BACE1 endosome-to-TGN trafficking through PACS1.

    PubMed

    Sun, Miao; Zhang, Huaye

    2017-12-01

    The cleavage of amyloid precursor protein (APP) by β-site APP cleaving enzyme 1 (BACE1) is the rate-limiting step in beta amyloid generation during Alzheimer's disease (AD) pathogenesis. In AD brains, BACE1 is abnormally accumulated in endocytic compartments, where the acidic pH is optimal for its activity. However, mechanisms regulating the endosome-to-trans-Golgi network (TGN) retrieval of BACE1 remain unclear. Here, we show that partitioning defective 3 (Par3) facilitates BACE1 retrograde trafficking from endosomes to the TGN. Par3 functions through aPKC-mediated phosphorylation of BACE1 on Ser498, which in turn promotes the interaction between BACE1 and phosphofurin acidic cluster sorting protein 1 and facilitates the retrograde trafficking of BACE1 to the TGN. In human AD brains, there is a significant decrease in Ser498 phosphorylation of BACE1 suggesting that defective phosphorylation-dependent retrograde transport of BACE1 is important in AD pathogenesis. Together, our studies provide mechanistic insight into a novel role for Par3 and aPKC in regulating the retrograde endosome-to-TGN trafficking of BACE1 and shed light on the mechanisms of AD pathogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Aggregate complexes of HIV-1 induced by multimeric antibodies.

    PubMed

    Stieh, Daniel J; King, Deborah F; Klein, Katja; Liu, Pinghuang; Shen, Xiaoying; Hwang, Kwan Ki; Ferrari, Guido; Montefiori, David C; Haynes, Barton; Pitisuttithum, Punnee; Kaewkungwal, Jaranit; Nitayaphan, Sorachai; Rerks-Ngarm, Supachai; Michael, Nelson L; Robb, Merlin L; Kim, Jerome H; Denny, Thomas N; Tomaras, Georgia D; Shattock, Robin J

    2014-10-02

    Antibody mediated viral aggregation may impede viral transfer across mucosal surfaces by hindering viral movement in mucus, preventing transcytosis, or reducing inter-cellular penetration of epithelia thereby limiting access to susceptible mucosal CD4 T cells and dendritic cells. These functions may work together to provide effective immune exclusion of virus from mucosal tissue; however little is known about the antibody characteristics required to induce HIV aggregation. Such knowledge may be critical to the design of successful immunization strategies to facilitate viral immune exclusion at the mucosal portals of entry. The potential of neutralizing and non-neutralizing IgG and IgA monoclonals (mAbs) to induce HIV-1 aggregation was assessed by Dynamic light scattering (DLS). Although neutralizing and non-neutralizing IgG mAbs and polyclonal HIV-Ig efficiently aggregated soluble Env trimers, they were not capable of forming viral aggregates. In contrast, dimeric (but not monomeric) IgA mAbs induced stable viral aggregate populations that could be separated from uncomplexed virions. Epitope specificity influenced both the degree of aggregation and formation of higher order complexes by dIgA. IgA purified from serum of uninfected RV144 vaccine trial responders were able to efficiently opsonize viral particles in the absence of significant aggregation, reflective of monomeric IgA. These results collectively demonstrate that dIgA is capable of forming stable viral aggregates providing a plausible basis for testing the effectiveness of aggregation as a potential protection mechanism at the mucosal portals of viral entry.

  1. HIV-1 vaccines

    PubMed Central

    Excler, Jean-Louis; Robb, Merlin L; Kim, Jerome H

    2014-01-01

    The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure. PMID:24637946

  2. Neuroprotective effects of curcumin on endothelin-1 mediated cell death in hippocampal neurons.

    PubMed

    Stankowska, Dorota L; Krishnamoorthy, Vignesh R; Ellis, Dorette Z; Krishnamoorthy, Raghu R

    2017-06-01

    Alzheimer's disease is a progressive neurodegenerative disease characterized by loss of hippocampal neurons leading to memory deficits and cognitive decline. Studies suggest that levels of the vasoactive peptide endothelin-1 (ET-1) are increased in the brain tissue of Alzheimer's patients. Curcumin, the main ingredient of the spice turmeric, has been shown to have anti-inflammatory, anti-cancer, and neuroprotective effects. However, the mechanisms underlying some of these beneficial effects are not completely understood. The objective of this study was to determine if curcumin could protect hippocampal neurons from ET-1 mediated cell death and examine the involvement of c-Jun in this pathway. Primary hippocampal neurons from rat pups were isolated using a previously published protocol. Viability of the cells was measured by the live/dead assay. Immunoblot and immunohistochemical analyses were performed to analyze c-Jun levels in hippocampal neurons treated with either ET-1 or a combination of ET-1 and curcumin. Apoptotic changes were evaluated by immunoblot detection of cleaved caspase-3, cleaved fodrin, and a caspase 3/7 activation assay. ET-1 treatment produced a 2-fold increase in the levels of c-Jun as determined by an immunoblot analysis in hippocampal neurons. Co-treatment with curcumin significantly attenuated the ET-1 mediated increase in c-Jun levels. ET-1 caused increased neuronal cell death of hippocampal neurons indicated by elevation of cleaved caspase-3, cleaved fodrin and an increased activity of caspases 3 and 7 which was attenuated by co-treatment with curcumin. Blockade of JNK, an upstream effector of c-Jun by specific inhibitor SP600125 did not fully protect from ET-1 mediated activation of pro-apoptotic enzymes in primary hippocampal cells. Our data suggests that one mechanism by which curcumin protects against ET-1-mediated cell death is through blocking an increase in c-Jun levels. Other possible mechanisms include decreasing pro

  3. Postdose 3 G1 serum neutralizing antibody as correlate of protection for pentavalent rotavirus vaccine.

    PubMed

    Liu, G Frank; Hille, Darcy; Kaplan, Susan S; Goveia, Michelle G

    2017-10-03

    Although clinical trials of the pentavalent rotavirus vaccine (RotaTeq®, RV5) have demonstrated efficacy against RV gastroenteritis (RGE) in low and high-income settings, a clear correlate of protection or a measure of immune response that could predict efficacy has yet to be identified. This is the first time that immunogenicity data with both serum neutralized antibody (SNA) titers and anti-RV IgA titers from several clinical efficacy trials were pooled to provide a unique context for evaluating the correlation between immunogenicity and RGE risk or efficacy of RV5. The correlation between immunogenicity and RGE risk is evaluated with data at the individual subject level. The analyses show that higher Postdose 3 (PD3) G1 SNA titers are associated with lower odds of contracting any RGE. The correlation between immunogenicity and efficacy is assessed using aggregated population level data, which shows higher efficacy associated with higher PD3 G1 SNA geometric mean titer (GMT) ratio (between RV5 and placebo) and PD3 serum anti-RV IgA GMT ratio. Among high-income countries, efficacy plateaus over the range of PD3 G1 SNA GMT ratios and PD3 serum anti-RV IgA GMT ratios. From both individual- and population-level analyses, PD3 G1 SNA titers correlated most closely with the RGE risk or efficacy for RV5.

  4. Application of Sparse Linear Discriminant Analysis and Elastic Net for Diagnosis of IgA Nephropathy: Statistical and Biological Viewpoints

    PubMed

    Mohammadi Majd, Tahereh; Kalantari, Shiva; Raeisi Shahraki, Hadi; Nafar, Mohsen; Almasi, Afshin; Samavat, Shiva; Parvin, Mahmoud; Hashemian, Amirhossein

    2018-03-10

    IgA nephropathy (IgAN) is the most common primary glomerulonephritis diagnosed based on renal biopsy. Mesangial IgA deposits along with the proliferation of mesangial cells are the histologic hallmark of IgAN. Non-invasive diagnostic tools may help to prompt diagnosis and therapy. The discovery of potential and reliable urinary biomarkers for diagnosis of IgAN depends on applying robust and suitable models. Applying two multivariate modeling methods on a urine proteomic dataset obtained from IgAN patients, and comparison of the results of these methods were the purpose of this study. Two models were constructed for urinary protein profiles of 13 patients and 8 healthy individuals, based on sparse linear discriminant analysis (SLDA) and elastic net regression methods. A panel of selected biomarkers with the best coefficients were proposed and further analyzed for biological relevance using functional annotation and pathway analysis. Transferrin, α1-antitrypsin, and albumin fragments were the most important up-regulated biomarkers, while fibulin-5, YIP1 family member 3, prasoposin, and osteopontin were the most important down-regulated biomarkers. Pathway analysis revealed that complement and coagulation cascades and extracellular matrix-receptor interaction pathways impaired in the pathogenesis of IgAN. SLDA and elastic net had an equal importance for diagnosis of IgAN and were useful methods for exploring and processing proteomic data. In addition, the suggested biomarkers are reliable candidates for further validation to non-invasive diagnose of IgAN based on urine examination.

  5. [Diabetes and autoimmune diseases: prevalence of celiac disease in children and adolescents with type 1 diabetes].

    PubMed

    Mont-Serrat, Camila; Hoineff, Claudio; Meirelles, Ricardo M R; Kupfer, Rosane

    2008-12-01

    Determine the prevalence of celiac disease in children and adolescents with type 1 diabetes mellitus (DM1) in attendance in Instituto Estadual de Diabetes e Endocrinologia Luiz Capriglione (IEDE). Blood samples were analyzed in 120 children and adolescents with DM1 from IEDE Diabetes Clinic for the IgA antitissue-transglutaminase antibody and dosage of the seric IgA. Those with positive serology were guided for upper endoscopy with small-bowel biopsy to confirm the celiac disease. The antibody was positive in 3 of the 120 patients. The small-bowel biopsy was confirmatory in all of the positive patients, leading to a prevalence of celiac disease of 2.5% in the studied group. The prevalence of celiac disease is increased in children and adolescents with DM1 when compared with normality. As most are asymptomatic, it is recommended periodical screening of celiac disease in children with DM1.

  6. A carboxy-terminal fragment of protein mu 1/mu 1C is present in infectious subvirion particles of mammalian reoviruses and is proposed to have a role in penetration.

    PubMed Central

    Nibert, M L; Fields, B N

    1992-01-01

    Penetration of a cell membrane as an early event in infection of cells by mammalian reoviruses appears to require a particular type of viral particle, the infectious subvirion particle (ISVP), which is generated from an intact virion by proteolytic cleavage of the outer capsid proteins sigma 3 and mu 1/mu 1C. Characterizations of the structural components and properties of ISVPs are thus relevant to attempts to understand the mechanism of penetration by reoviruses. In this study, a novel, approximately 13-kDa carboxy-terminal fragment (given the name phi) was found to be generated from protein mu 1/mu 1C during in vitro treatments of virions with trypsin or chymotrypsin to yield ISVPs. With trypsin treatment, both the carboxy-terminal fragment phi and the amino-terminal fragment mu 1 delta/delta were shown to be generated and to remain attached to ISVPs in stoichiometric quantities. Sites of protease cleavage were identified in the deduced amino acid sequence of mu 1 by determining the amino-terminal sequences of phi proteins: trypsin cleaves between arginine 584 and isoleucine 585, and chymotrypsin cleaves between tyrosine 581 and glycine 582. Findings in this study indicate that sequences in the phi portion of mu 1/mu 1C may participate in the unique functions attributed to ISVPs. Notably, the delta-phi cleavage junction was predicted to be flanked by a pair of long amphipathic alpha-helices. These amphipathic alpha-helices, together with the myristoyl group at the extreme amino terminus of mu 1/mu 1N, are proposed to interact directly with the lipid bilayer of a cell membrane during penetration by mammalian reoviruses. Images PMID:1328674

  7. Crystal structure of Pistol, a class of self-cleaving ribozyme

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Laura A.; Wang, Jimin; Steitz, Thomas A.

    2017-01-17

    Small self-cleaving ribozymes have been discovered in all evolutionary domains of life. They can catalyze site-specific RNA cleavage, and as a result, they have relevance in gene regulation. Comparative genomic analysis has led to the discovery of a new class of small self-cleaving ribozymes named Pistol. We report the crystal structure of Pistol at 2.97-Å resolution. Our results suggest that the Pistol ribozyme self-cleavage mechanism likely uses a guanine base in the active site pocket to carry out the phosphoester transfer reaction. The guanine G40 is in close proximity to serve as the general base for activating the nucleophile bymore » deprotonating the 2'-hydroxyl to initiate the reaction (phosphoester transfer). Furthermore, G40 can also establish hydrogen bonding interactions with the nonbridging oxygen of the scissile phosphate. The proximity of G32 to the O5' leaving group suggests that G32 may putatively serve as the general acid. The RNA structure of Pistol also contains A-minor interactions, which seem to be important to maintain its tertiary structure and compact fold. Our findings expand the repertoire of ribozyme structures and highlight the conserved evolutionary mechanism used by ribozymes for catalysis.« less

  8. Molecular Basis for the Relative Substrate Specificity of Human Immunodeficiency Virus Type 1 and Feline Immunodeficiency Virus Proteases

    PubMed Central

    Beck, Zachary Q.; Lin, Ying-Chuan; Elder, John H.

    2001-01-01

    We have used a random hexamer phage library to delineate similarities and differences between the substrate specificities of human immunodeficiency virus type 1 (HIV-1) and feline immunodeficiency virus (FIV) proteases (PRs). Peptide sequences were identified that were specifically cleaved by each protease, as well as sequences cleaved equally well by both enzymes. Based on amino acid distinctions within the P3-P3′ region of substrates that appeared to correlate with these cleavage specificities, we prepared a series of synthetic peptides within the framework of a peptide sequence cleaved with essentially the same efficiency by both HIV-1 and FIV PRs, Ac-KSGVF↓VVNGLVK-NH2 (arrow denotes cleavage site). We used the resultant peptide set to assess the influence of specific amino acid substitutions on the cleavage characteristics of the two proteases. The findings show that when Asn is substituted for Val at the P2 position, HIV-1 PR cleaves the substrate at a much greater rate than does FIV PR. Likewise, Glu or Gln substituted for Val at the P2′ position also yields peptides specifically susceptible to HIV-1 PR. In contrast, when Ser is substituted for Val at P1′, FIV PR cleaves the substrate at a much higher rate than does HIV-1 PR. In addition, Asn or Gln at the P1 position, in combination with an appropriate P3 amino acid, Arg, also strongly favors cleavage by FIV PR over HIV PR. Structural analysis identified several protease residues likely to dictate the observed specificity differences. Interestingly, HIV PR Asp30 (Ile-35 in FIV PR), which influences specificity at the S2 and S2′ subsites, and HIV-1 PR Pro-81 and Val-82 (Ile-98 and Gln-99 in FIV PR), which influence specificity at the S1 and S1′ subsites, are residues which are often involved in development of drug resistance in HIV-1 protease. The peptide substrate KSGVF↓VVNGK, cleaved by both PRs, was used as a template for the design of a reduced amide inhibitor, Ac-GSGVFΨ(CH2NH)VVNGL-NH2

  9. Anti-type II collagen antibodies, anti-CCP, IgA RF and IgM RF are associated with joint damage, assessed eight years after onset of juvenile idiopathic arthritis (JIA)

    PubMed Central

    2014-01-01

    Background Early appearance of antibodies specific for native human type II collagen (anti-CII) characterizes an early inflammatory and destructive phenotype in adults with rheumatoid arthritis (RA). The objective of this study was to investigate the occurrence of anti-CII, IgM RF, IgA RF and anti-CCP in serum samples obtained early after diagnosis, and to relate the occurrence of autoantibodies to outcome after eight years of disease in children with juvenile idiopathic arthritis (JIA). Methods The Nordic JIA database prospectively included JIA patients followed for eight years with data on remission and joint damage. From this database, serum samples collected from 192 patients, at a median of four months after disease onset, were analysed for IgG anti-CII, IgM RF, IgA RF and IgG anti-CCP. Joint damage was assessed based on Juvenile Arthritis Damage Index for Articular damage (JADI-A), a validated clinical instrument for joint damage. Results Elevated serum levels of anti-CII occurred in 3.1%, IgM RF in 3.6%, IgA RF in 3.1% and anti-CCP in 2.6% of the patients. Occurrence of RF and anti-CCP did to some extent overlap, but rarely with anti-CII. The polyarticular and oligoarticular extended categories were overrepresented in patients with two or more autoantibodies. Anti-CII occurred in younger children, usually without overlap with the other autoantibodies and was associated with high levels of C-reactive protein (CRP) early in the disease course. All four autoantibodies were significantly associated with joint damage, but not with active disease at the eight-year follow up. Conclusions Anti-CII, anti-CCP, IgA RF and IgM RF detected early in the disease course predicted joint damage when assessed after eight years of disease. The role of anti-CII in JIA should be further studied. PMID:24944545

  10. Effect of the Various Steps in the Processing of Human Milk in the Concentrations of IgA, IgM, and Lactoferrin.

    PubMed

    Arroyo, Gerardo; Ortiz Barrientos, Kevin Alexander; Lange, Karla; Nave, Federico; Miss Mas, Gabriela; Lam Aguilar, Pamela; Soto Galindo, Miguel Angel

    2017-09-01

    Human milk immune components are unique and important for the development of the newborn. Milk processing at the Human Milk Banks (HMB), however, causes partial destruction of immune proteins. The objective of this study was to determine the effects that heating during the milk processing procedure at the HMB had on the concentrations of IgA, IgM, and lactoferrin at three critical points in time. Fifty milk samples (150 mL) were collected from voluntary donors at the HMB at the Hospital Nacional Pedro de Bethancourt, located in Antigua Guatemala. Samples from three critical points in time during the milk processing procedure were selected for analysis: freezing/thawing I, freezing/thawing II, and pasteurization. IgA, IgM, and lactoferrin concentrations were determined during each critical point and compared with a baseline concentration. After milk processing, IgA, IgM, and lactoferrin mean concentrations were reduced by 30.0%, 36.0%, and 70.0%, respectively (p < 0.001). Reduction of biological activity was mainly attributed to pasteurization for IgA and lactoferrin (p < 0.001); the first freezing/thawing processes before pasteurization showed no significant reduction difference between mean concentrations of IgA (p = 0.160) and lactoferrin (p = 0.345) but showed a significant effect on IgM concentration (p = 0.016), and the second freezing/thawing procedure only showed a significant effect on IgA (p < 0.001). The effects of milk processing on the immune proteins that were evaluated in this study demonstrated a significant reduction.

  11. Targeted deletion of RANKL in M cell inducer cells by the Col6a1-Cre driver.

    PubMed

    Nagashima, Kazuki; Sawa, Shinichiro; Nitta, Takeshi; Prados, Alejandro; Koliaraki, Vasiliki; Kollias, George; Nakashima, Tomoki; Takayanagi, Hiroshi

    2017-11-04

    The gut-associated lymphoid tissues (GALTs), including Peyer's patches (PPs), cryptopatches (CPs) and isolated lymphoid follicles (ILFs), establish a host-microbe symbiosis by the promotion of immune reactions against gut microbes. Microfold cell inducer (MCi) cells in GALTs are the recently identified mesenchymal cells that express the cytokine RANKL and initiate bacteria-specific immunoglobulin A (IgA) production via induction of microfold (M) cell differentiation. In the previous study, the Twist2-Cre driver was utilized for gene deletion in mesenchymal cells including MCi cells. In order to investigate MCi cells more extensively, it will be necessary to develop experimental tools in addition to the Twist2-Cre driver mice and characterize such drivers in specificity and efficiency. Here we show that M cell differentiation and IgA production are impaired in the targeted deletion of RANKL by the Col6a1-Cre driver. We compared Col6a1-Cre with Twist2-Cre in terms of the specificity for mesenchymal cells in GALTs. Col6a1-Cre CAG-CAT-EGFP mice exhibited EGFP expression in podoplanin + CD31 - cells including MCi cells, while Twist2-Cre mice were shown to target endothelial cells and podoplanin + CD31 - cells. Tnfsf11 fl/Δ Col6a1-Cre mice exhibited the absence of M cells and severe IgA reduction together with an alteration in gut microbial composition. Moreover, we analyzed germ free mice to test whether changes in the microbiota are the cause of M cell deficiency. M cell differentiation was normal in the CPs/ILFs of germ free mice, indicating that MCi cells induce M cells independently of microbial colonization. This study demonstrates that Col6a1-Cre driver mice are as useful as Twist2-Cre driver mice for functional analyses of GALT-resident mesenchymal cells, including MCi cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Sensitivity and specificity of single IgA and IgG antibody concentrations for early diagnosis of pertussis in adults: an evaluation for outbreak management in public health practice

    PubMed Central

    Mertens, Paul LJM; Stals, Frans S; Steyerberg, Ewout W; Richardus, Jan H

    2007-01-01

    Background An accurate, practical laboratory test is needed to confirm clinical diagnosis of pertussis in adults during the first 3 symptomatic weeks, when treatment is effective and transmission can be interrupted. Methods The sensitivity and specificity of single IgA and IgG levels were assessed in a cohort study of a pertussis epidemic in 99 adults in a closed community. Sensitivities were assessed in the sera of 46 laboratory confirmed clinical pertussis cases during the first 3 weeks. Specificities were calculated in sera of 35 asymptomatic controls without clinical symptoms or laboratory confirmed infections from the same community (internal controls). We compared these specificities with the specificities of single IgA and IgG levels in 4275 external controls from a cross-section of the general Dutch population aged 21–79 years who had not coughed for more than 2 weeks in the past year, and without pertussis diagnoses. The study was done in the Netherlands when whole-cell pertussis vaccine was used in the national vaccination programme. Results Levels of 24 U/ml for IgA and 27 U/ml for IgG gave sensitivities of 100% and 75%, respectively, in the first 2 weeks, 100% in the third week, and 97% after the fourth week. The levels were reached within 2 days after onset of increase, and remained above these levels for roughly 7.2 and 5.1 months, respectively. Specificity was 82% for IgA and 89% for IgG in the internal controls and 90% in the external controls, respectively. Conclusion We suggest levels of 24 U/ml for IgA level and 27 U/ml (= 27 International Units (IU)/ml) for IgG as sensitive, specific, and practical for laboratory confirmation of clinical pertussis in adults in the first 3 weeks of outbreak management. PMID:17553132

  13. Corticosteroids in IgA Nephropathy: A Retrospective Analysis from the VALIGA Study.

    PubMed

    Tesar, Vladimir; Troyanov, Stéphan; Bellur, Shubha; Verhave, Jacobien C; Cook, H Terence; Feehally, John; Roberts, Ian S D; Cattran, Daniel; Coppo, Rosanna

    2015-09-01

    Current guidelines suggest treatment with corticosteroids (CS) in IgA nephropathy (IgAN) when proteinuria is persistently ≥1 g/d despite 3-6 months of supportive care and when eGFR is >50 ml/min per 1.73 m(2). Whether the benefits of this treatment extend to patients with an eGFR≤50 ml/min per 1.73 m(2), other levels of proteinuria, or different renal pathologic lesions remains unknown. We retrospectively studied 1147 patients with IgAN from the European Validation Study of the Oxford Classification of IgAN (VALIGA) cohort classified according to the Oxford-MEST classification and medication used, with details of duration but not dosing. Overall, 46% of patients received immunosuppression, of which 98% received CS. Treated individuals presented with greater clinical and pathologic risk factors of progression. They also received more antihypertensive medication, and a greater proportion received renin angiotensin system blockade (RASB) compared with individuals without immunosuppressive therapy. Immunosuppression was associated with a significant reduction in proteinuria, a slower rate of renal function decline, and greater renal survival. Using a propensity score, we matched 184 subjects who received CS and RASB to 184 patients with a similar risk profile of progression who received only RASB. Within this group, CS reduced proteinuria and the rate of renal function decline and increased renal survival. These benefits extended to those with an eGFR≤50 ml/min per 1.73 m(2), and the benefits increased proportionally with the level of proteinuria. Thus, CS reduced the risk of progression regardless of initial eGFR and in direct proportion to the extent of proteinuria in this cohort. Copyright © 2015 by the American Society of Nephrology.

  14. Relationship between the IgA antibody response against Streptococcus mutans GbpB and severity of dental caries in childhood.

    PubMed

    Colombo, Natália Helena; Pereira, Jesse Augusto; da Silva, Márjully Eduardo Rodrigues; Ribas, Laís Fernanda Fonseca; Parisotto, Thaís Manzano; Mattos-Graner, Renata de Oliveira; Smith, Daniel J; Duque, Cristiane

    2016-07-01

    Explore the associations between the severity of dental caries in childhood, mutans streptococci (MS) levels and IgA antibody response against Streptococcus mutans GbpB. Moreover, other caries-related etiological factors were also investigated. 36-60 month-old children were grouped into Caries-Free (CF, n=19), Early Childhood Caries (ECC, n=17) and Severe Early Childhood Caries (S-ECC, n=21). Data from socio-economic-cultural status, oral hygiene habits and dietary patterns were obtained from a questionnaire and a food-frequency diary filled out by parents. Saliva was collected from children for microbiological analysis and detection of salivary IgA antibody reactive with S. mutans GbpB in western blot. S-ECC children had reduced family income compared to those with ECC and CF. There was difference between CF and caries groups (ECC and S-ECC) in MS counts. Positive correlations between salivary IgA antibody response against GbpB and MS counts were found when the entire population was evaluated. When children with high MS counts were compared, S-ECC group showed significantly lower IgA antibody levels to GbpB compared to CF group. This finding was not observed for the ECC group. This study suggests that children with S-ECC have reduced salivary IgA immune responses to S. mutans GbpB, potentially compromising their ability to modify MS infection and its cariogenic potential. Furthermore, a reduced family income and high levels of MS were also associated with S-ECC. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. IGA resistance of TT Alloy 690 and concentration behavior of Broached Egg Crate tube support configuration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suzuki, S.; Kusakabe, T.; Yamamoto, H.

    1992-12-31

    In order to improve the reliability of the Steam Generator (SG), TT Alloy 690 and BEC (Broached Egg Crate) type tube support plate has been developed. Some tests are carried out to heighten the reliability for these improvements all the more and the following results are obtained. (1) SERT test (Slow Extension Rate Test) made clear that TT690 has less IGA susceptibility in comparison with MA600. (2) The alkaline susceptibility on the occurrence of IGA/SCC on TT690 and MA600 obtained by SERT corresponds to that obtained by Model Boiler test. (3) By model boiler test, superior concentration behaviors for BECmore » type tube support plate configuration have been recognized in comparison with Drill type. This result is obtained by the joint research of the five utilities (Kansai Epco, Hokkaido Epco, Shikoku Epco, Kyushu Epco, JAPCO) and MHI.« less

  16. Effect of Minerals on Intestinal IgA Production Using Deep Sea Water Drinks.

    PubMed

    Shiraishi, Hisashi; Fujino, Maho; Shirakawa, Naoki; Ishida, Nanao; Funato, Hiroki; Hirata, Ayumu; Abe, Noriaki; Iizuka, Michiro; Jobu, Kohei; Yokota, Junko; Miyamura, Mitsuhiko

    2017-01-01

    Minerals are essential for life, as they are a vital part of protein constituents, enzyme cofactors, and other components in living organisms. Deep sea water is characterized by its cleanliness and stable low temperature, and its possible health- and medical benefits are being studied. However, no study has yet evaluated the physical properties of the numerous commercially available deep sea water products, which have varying water sources and production methods. We analyzed these products' mineral content and investigated their effect on living organism, focusing on immune functions, and investigated the relation between physiological immunoactivities and mineral intake. We qualitatively analyzed the mineral compositions of the deep sea water drinks and evaluated the drinks' physical properties using principal component analysis, a type of multivariate analysis, of their mineral content. We create an iron and copper-deficient rat model and administered deep sea water drinks for 8 weeks. We then measured their fecal immunoglobulin A (IgA) to evaluate immune function. Principal component analysis suggested that physical properties of deep sea water drinks could be determined by their sources. Administration of deep sea water drinks increased fecal IgA, thus tending to stimulate immune function, but the extent of this effect varied by drink. Of the minerals contained in deep sea water, iron showed positive correlations with the fecal IgA. The principal component analysis used in this study is suitable for evaluating deep sea water containing many minerals, and our results form a useful basis for comparative evaluations of deep sea water's bioactivity.

  17. Secretory IgA: Designed for Anti-Microbial Defense

    PubMed Central

    Brandtzaeg, Per

    2013-01-01

    Prevention of infections by vaccination remains a compelling goal to improve public health. Mucosal vaccines would make immunization procedures easier, be better suited for mass administration, and most efficiently induce immune exclusion – a term coined for non-inflammatory antibody shielding of internal body surfaces, mediated principally by secretory immunoglobulin A (SIgA). The exported antibodies are polymeric, mainly IgA dimers (pIgA), produced by local plasma cells (PCs) stimulated by antigens that target the mucose. SIgA was early shown to be complexed with an epithelial glycoprotein – the secretory component (SC). A common SC-dependent transport mechanism for pIgA and pentameric IgM was then proposed, implying that membrane SC acts as a receptor, now usually called the polymeric Ig receptor (pIgR). From the basolateral surface, pIg-pIgR complexes are taken up by endocytosis and then extruded into the lumen after apical cleavage of the receptor – bound SC having stabilizing and innate functions in the secretory antibodies. Mice deficient for pIgR show that this is the only receptor responsible for epithelial export of IgA and IgM. These knockout mice show a variety of defects in their mucosal defense and changes in their intestinal microbiota. In the gut, induction of B-cells occurs in gut-associated lymphoid tissue, particularly the Peyer’s patches and isolated lymphoid follicles, but also in mesenteric lymph nodes. PC differentiation is accomplished in the lamina propria to which the activated memory/effector B-cells home. The airways also receive such cells from nasopharynx-associated lymphoid tissue but by different homing receptors. This compartmentalization is a challenge for mucosal vaccination, as are the mechanisms used by the mucosal immune system to discriminate between commensal symbionts (mutualism), pathobionts, and overt pathogens (elimination). PMID:23964273

  18. Discovery of potent peptide-mimetic antagonists for the human thrombin receptor, protease-activated receptor-1 (PAR-1).

    PubMed

    Maryanoff, Bruce E; Zhang, Han-Cheng; Andrade-Gordon, Patricia; Derian, Claudia K

    2003-03-01

    Protease-activated receptors (PARs) represent a unique family of seven-transmembrane G-protein-coupled receptors, which are enzymatically cleaved to expose a new extracellular N-terminus that acts as a tethered activating ligand. PAR-1 is cleaved and activated by the serine protease alpha-thrombin, is expressed in various tissues (e.g. platelets and vascular cells), and is involved in cellular responses associated with hemostasis, proliferation, and tissue injury. By using a de novo design approach, we have discovered a series of potent heterocycle-based peptide-miimetic antagonists of PAR-1, exemplified by advanced leads RWJ-56110 (22) and RWJ-58259 (32). These compounds are potent, selective PAR-1 antagonists, devoid of PAR-1 agonist and thrombin inhibitory activity: they bind to PAR-1, interfere with calcium mobilization and cellular functions associated with PAR-1, and do not affect PAR-2, PAR-3, or PAR-4. RWJ-56110 was determined to be a direct inhibitor of PAR-1 activation and internalization, without affecting PAR-1 N-terminal cleavage. At high concentrations of alpha-thrombin, RWJ-56110 fully blocked activation responses in human vascular cells, but not in human platelets; whereas, at high concentrations of TRAP-6, RWJ-56110 blocked activation responses in both cell types. This result is consistent with the presence of another thrombin receptor on human platelets, namely PAR-4. RWJ-56110 and RWJ-58259 clearly interrupt the binding of a tethered ligand to its receptor. RWJ-58259 demonstrated antirestenotic activity in a rat balloon angioplasty model and antithrombotic activity in a cynomolgus monkey arterial injury model. Such PAR-1 antagonists should not only serve as useful tools to delineate the physiological and pathophysiological roles of PAR-1, but also may have therapeutic potential for treating thrombosis and restenosis in humans.

  19. Microparticulate Caspase-1 Regulates Gasdermin-D and Pulmonary Vascular Endothelial Cell Injury.

    PubMed

    Mitra, Srabani; Exline, Matthew; Habyarimana, Fabien; Gavrilin, Mikhail; Baker, Paul; Masters, Seth L; Wewers, Mark D; Sarkar, Anasuya

    2018-01-24

    Lung endothelial cell apoptosis and injury occurs throughout all stages of acute lung injury (ALI/ARDS) and impacts disease progression. Caspases 1, 4 and 5 are essential for completion of the apoptotic program known as pyroptosis that also involves pro-inflammatory cytokines. Because GSDM-D mediates pyroptotic death and is essential for pore formation, we hypothesized that it may direct caspase-1 encapsulated microparticle (MP) release and mediate endothelial cell death. Our current work provides evidence that GSDM-D is released by LPS stimulated THP1 monocytic cells where it is packaged into microparticles along with active caspase-1. Furthermore, only MP released from stimulated monocytic cells that contain both cleaved GSDM-D and active caspase-1 induce endothelial cell apoptosis. MPs pretreated with caspase-1 inhibitor, YVAD, or pan-caspase inhibitor, ZVAD, do not contain cleaved GSDM-D. MPs from caspase-1KO cells are also deficient in p30 active GSDM-D, further confirming that caspase-1 regulates GSDM-D function. Although control MPs contained cleaved GSDM-D without caspase-1, these fractions were unable to induce cell death, suggesting that encapsulation of both caspase-1 and GSDM-D is essential for cell death induction. Release of microparticulate active caspase-1 was abrogated in GSDM-KO cells, although cytosolic caspase-1 activation was not impaired. Lastly, higher levels of microparticulate GSDM-D was detected in septic ARDS patient plasma when compared to healthy donors. Taken together, these findings suggest that GSDM-D regulates the release of microparticulate active caspase-1 from monocytes essential for induction of cell death and thereby may play a critical role in sepsis-induced endothelial cell injury.

  20. The structural and electronic properties of cleaved silicon (111) surfaces following adsorption of silver

    NASA Astrophysics Data System (ADS)

    Le Lay, G.; Chauvet, A.; Manneville, M.; Kern, R.

    Silver overlayers for coverages ranging from zero to several monolayers are evaporated on vacuum-cleaved (111) silicon surfaces and carefully examined using low-energy electron diffraction (diffraction patterns and I(v) curves), and Auger electron spectroscopy (condensation/desorption curves), with the aim of establishing a closer correlation between the adsorption process, the different superlattices observed (i.e. 7 × 7-R(±19°1), 3 × 3-R(30° ), 3 × 1 and 6 × 1), the growth mechanism of the deposit on the one hand and the electronic properties of the system recently probed using photoemission yield spectroscopy on the other hand. These new results basically confirm the direct relations we had previously shown between the growth mode as monitored with electron diffraction LEED, RHEED, TED and Auger spectroscopy, and the electronic structures as investigated by low energy electron spectroscopy, but permit a deeper insight into the adsorption process at low coverage. At room temperature on the 2 × 1 cleavage structure where the silver-silicon interaction is weak, the adsorbed phase is completed at about 6/7 of a monolayer (θ ≃ 6/7) and a local arrangement of vacancies in the adlayer yields the 7 superstructure, while little effect on the silicon dangling bonds is noticed, but when silver two-dimensional islands (θ > 6/7) growing in a quasi layer fashion have covered the substrate surface. At higher temperatures three-dimensional growth of crystallites occurs after completion of the 3 phase whose saturation coverage increases with condensation temperatures, maxima ranging from θ ˜ 0.7 to θ ˜ 1.0 ( T ˜ 500°C) for different cleaves. This Si(111) 3-Ag surface exhibits again the same dangling bond peak as a clean 2 × 1 Si surface, despite the fact that the interaction between Ag and Si is now rather strong, as is confirmed by desorption experiments ( T ˜ 600°C). We thus critically discuss the geometrical models of this 3 phase previously devised and

  1. Multiple inflammasomes may regulate the interleukin-1-driven inflammation in protracted bacterial bronchitis.

    PubMed

    Chen, Alice C-H; Tran, Hai B; Xi, Yang; Yerkovich, Stephanie T; Baines, Katherine J; Pizzutto, Susan J; Carroll, Melanie; Robertson, Avril A B; Cooper, Matthew A; Schroder, Kate; Simpson, Jodie L; Gibson, Peter G; Hodge, Greg; Masters, Ian B; Buntain, Helen M; Petsky, Helen L; Prime, Samantha J; Chang, Anne B; Hodge, Sandra; Upham, John W

    2018-01-01

    Protracted bacterial bronchitis (PBB) in young children is characterised by prolonged wet cough, prominent airway interleukin (IL)-1β expression and infection, often with nontypeable Haemophilus influenzae (NTHi). The mechanisms responsible for IL-1-driven inflammation in PBB are poorly understood. We hypothesised that the inflammation in PBB involves the NLRP3 and/or AIM2 inflammasome/IL-1β axis. Lung macrophages obtained from bronchoalveolar lavage (BAL), peripheral blood mononuclear cells (PBMCs), blood monocytes and monocyte-derived macrophages from patients with PBB and age-matched healthy controls were cultured in control medium or exposed to live NTHi. In healthy adult PBMCs, CD14 + monocytes contributed to 95% of total IL-1β-producing cells upon NTHi stimulation. Stimulation of PBB PBMCs with NTHi significantly increased IL-1β expression (p<0.001), but decreased NLRC4 expression (p<0.01). NTHi induced IL-1β secretion in PBMCs from both healthy controls and patients with recurrent PBB. This was inhibited by Z-YVAD-FMK (a caspase-1 selective inhibitor) and by MCC950 (a NLRP3 selective inhibitor). In PBB BAL macrophages inflammasome complexes were visualised as fluorescence specks of NLRP3 or AIM2 colocalised with cleaved caspase-1 and cleaved IL-1β. NTHi stimulation induced formation of specks of cleaved IL-1β, NLRP3 and AIM2 in PBMCs, blood monocytes and monocyte-derived macrophages. We conclude that both the NLRP3 and AIM2 inflammasomes probably drive the IL-1β-dominated inflammation in PBB.

  2. Multiple inflammasomes may regulate the interleukin-1-driven inflammation in protracted bacterial bronchitis

    PubMed Central

    Chen, Alice C-H.; Tran, Hai B.; Xi, Yang; Yerkovich, Stephanie T.; Baines, Katherine J.; Pizzutto, Susan J.; Carroll, Melanie; Robertson, Avril A.B.; Cooper, Matthew A.; Schroder, Kate; Simpson, Jodie L.; Gibson, Peter G.; Hodge, Greg; Masters, Ian B.; Buntain, Helen M.; Petsky, Helen L.; Chang, Anne B.; Hodge, Sandra; Upham, John W.

    2018-01-01

    Protracted bacterial bronchitis (PBB) in young children is characterised by prolonged wet cough, prominent airway interleukin (IL)-1β expression and infection, often with nontypeable Haemophilus influenzae (NTHi). The mechanisms responsible for IL-1-driven inflammation in PBB are poorly understood. We hypothesised that the inflammation in PBB involves the NLRP3 and/or AIM2 inflammasome/IL-1β axis. Lung macrophages obtained from bronchoalveolar lavage (BAL), peripheral blood mononuclear cells (PBMCs), blood monocytes and monocyte-derived macrophages from patients with PBB and age-matched healthy controls were cultured in control medium or exposed to live NTHi. In healthy adult PBMCs, CD14+ monocytes contributed to 95% of total IL-1β-producing cells upon NTHi stimulation. Stimulation of PBB PBMCs with NTHi significantly increased IL-1β expression (p<0.001), but decreased NLRC4 expression (p<0.01). NTHi induced IL-1β secretion in PBMCs from both healthy controls and patients with recurrent PBB. This was inhibited by Z-YVAD-FMK (a caspase-1 selective inhibitor) and by MCC950 (a NLRP3 selective inhibitor). In PBB BAL macrophages inflammasome complexes were visualised as fluorescence specks of NLRP3 or AIM2 colocalised with cleaved caspase-1 and cleaved IL-1β. NTHi stimulation induced formation of specks of cleaved IL-1β, NLRP3 and AIM2 in PBMCs, blood monocytes and monocyte-derived macrophages. We conclude that both the NLRP3 and AIM2 inflammasomes probably drive the IL-1β-dominated inflammation in PBB. PMID:29594175

  3. [Fabry nephropathy in a female with superposed IgA glomerulonephritis].

    PubMed

    Pisani, A; Sessa, A; Sabbatini, M; Andreucci, M V; Fusco, C; Balletta, M; Cianciaruso, B

    2005-01-01

    In Anderson-Fabry disease (AFd), the kidney is affected in all hemizygous males and in some heterozygous females. Female carriers can present subtle renal abnormalities due to glycosphingolipid (GSL) accumulation within renal cells. Renal biopsy is rarely performed in female Fabry patients because clinical renal manifestations are usually lacking. However, female carriers can accumulate GSL in their renal cells despite the absence of clinically evident kidney disease. We performed a kidney biopsy in a 52-year-old female patient, a Fabry disease carrier. The patient showed normal glomerular filtration rate, persistent microhematuria and proteinuria (about 1.7 g/24 hr), cornea "verticillata", and evident left ventricular hypertrophy. The molecular study documented a missense mutation R227Q in exon 5 of the alpha-galactosidase A gene. Optical microscopy showed electron-dense mesangial deposits due IgA glomerulonephritis, as confirmed by immunofluorescence. We decided to start therapy with angiotensin-converting enzyme inhibitors (ACE-I). After 8 months of treatment, the patient demonstrated proteinuria of 0.9 g/24 hr. To decide when to start treatment using enzyme replacement therapy (ERT) with human recombinant GAL A (Fabrazyme), we decided to perform an electron microscopy study of the renal biopsy. The renal ultrastructural findings were typical GSL inclusions in all kinds of glomerular cells, in tubular epithelial cells and in endothelial cells of interstitial capillaries, confirming the hypothesis of Fabry nephropathy. Consequently, Fabrazyme was given at a standard dose of 1 mg/kg every 2 weeks. After 24 months of combined treatment (ACE-I-Fabrazyme), proteinuria decreased to 0.2 g/24 hr. The importance of performing the ultrastructural examination of the kidney biopsy is stressed, especially in heterozygous Fabry patients to evaluate the need to treat them with ERT and to evaluate the degree of renal involvement.

  4. Human milk containing specific secretory IgA inhibits binding of Giardia lamblia to nylon and glass surfaces.

    PubMed

    Samra, H K; Ganguly, N K; Mahajan, R C

    1991-06-01

    The effects of human milk, containing specific secretory IgA, on the adherence of Giardia lamblia trophozoites in the presence and in the absence of intestinal mucus in vitro were studied. It was found that the trophozoites treated with breast milk, containing specific secretory IgA to G. lamblia, showed a significant decrease (p less than 0.01) in adherence to nylon fibre columns and glass surfaces than did trophozoites treated with milk containing no SIgA antibodies. The adherence to glass surfaces was significantly more (p less than 0.01) in the presence of intestinal mucus than when the mucus was absent. Milk that did not contain specific secretory SIgA to G. lamblia did not decrease the adherence to glass surfaces either in the presence or in the absence of mucus. The fluorescence study revealed the binding of specific secretory IgA on the trophozoite surface. The results suggest that binding of SIgA antibodies in milk to G. lamblia trophozoites inhibits parasite adherence, thus protecting against this infection in breast-fed babies.

  5. Active tuberculosis patients have high levels of IgA anti-alpha-crystallin and isocitrate lyase proteins.

    PubMed

    Talavera-Paulín, M; García-Morales, L; Ruíz-Sánchez, B P; Caamal-Ley, Á D; Hernández-Solis, A; Ramírez-Casanova, E; Cicero-Sabido, R; Espitia, C; Helguera-Repetto, C; González-Y-Merchand, J A; Flores-Mejía, R; Estrada-Parra, S; Estrada-García, I; Chacón-Salinas, R; Wong-Baeza, I; Serafín-López, J

    2016-12-01

    Mexico City, Mexico. To identify proteins synthetised by Mycobacterium tuberculosis in hypoxic culture, which resemble more closely a granuloma environment than aerobic culture, and to determine if they are recognised by antibodies from patients with active pulmonary tuberculosis (PTB). Soluble extracts from M. tuberculosis H37Rv cultured under aerobic or hypoxic conditions were analysed using two-dimensional polyacrylamide gel electrophoresis, and proteins over-expressed under hypoxia were identified by mass spectrometry. The presence of immunoglobulin (Ig) G, IgA and IgM antibodies against these proteins was determined in the serum of 42 patients with active PTB and 42 healthy controls. We selected three M. tuberculosis H37Rv proteins (alpha-crystallin protein [Acr, Rv2031c], universal stress protein Rv2623 and isocitrate lyase [ICL, RV0467]) that were over-expressed under hypoxia. Titres of anti-Acr and anti-ICL IgA antibodies were higher in patients than in healthy controls, with an area under the receiver operating characteristic curve of 0.71 for anti-ICL IgA antibodies. ICL could be used in combination with other M. tuberculosis antigens to improve the sensitivity and specificity of current serological TB diagnostic methods.

  6. Circulating IgA immune complexes in patients with psoriasis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hall, R.P.; Peck, G.L.; Lawley, T.J.

    1983-06-01

    The sera of 21 patients with psoriasis were examined for the presence of IgA-containing circulating immune complexes (CIC) using the Raji IgA radioimmunoassay. In addition, the Raji IgG radioimmunoassay and 125I-Clq binding assay were used to detect IgG- and IgM-containing CIC. Twenty-five patients with other hyperkeratotic skin disorders were studied as controls. Patients were studied before institution of systemic therapy with etretinate (20 patients) or 13-cis-retinoic acid (1 patient). In addition, sera of 15 of the patients treated with etretinate were studied before, during, and after therapy. The extent of pretreatment disease involvement as well as response to therapy weremore » evaluated in a blinded fashion. Fourteen of 21 (67%) patients with psoriasis had evidence of IgA-containing CIC at some time during the course of their disease, as compared to only 1 of 25 patients with other hyperkeratotic skin disorders. In contrast, only 2 of 19 (11%) had evidence of IgG-containing CIC using the Raji IgG assay, and only 1 of 19 (5%) had evidence of IgG- or IgM-containing CIC using the 125I-Clq binding assay. A positive correlation was found between the extent of pretreatment disease involvement and the level of IgA-containing CIC by linear regression analysis (p . 0.01). There was, however, no correlation between clinical improvement and the presence or level of IgA-containing CIC in 15 patients followed during therapy. Sucrose density gradient analysis of the IgA-containing CIC found in 2 of these patients demonstrated IgA-containing CIC in the 9S to 13S region. The finding of IgA-containing CIC in a significant number of patients with psoriasis and the relative absence of IgG- or IgM-containing CIC suggest that IgA-containing CIC may play a role in psoriasis.« less

  7. Pre-transplant course and risk of kidney transplant failure in IgA nephropathy patients.

    PubMed

    Bjørneklett, Rune; Vikse, Bjørn Egil; Smerud, Hilde Kloster; Bostad, Leif; Leivestad, Torbjørn; Hartmann, Anders; Iversen, Bjarne M

    2011-01-01

    There is lack of knowledge to what degree clinical/morphological presentation and course of IgA nephropathy (IgAN) prior to end-stage renal disease are risk factors for graft loss after kidney transplantation. Patients with IgAN between 1988 and 2006 (registered in the Norwegian Kidney Biopsy Registry) who later received a kidney transplant (registered in the Norwegian Renal Registry) were included. The cohort was followed up regarding death-censored graft loss throughout 2008. Graft survival with a rapid progressive (RP) vs. a slow progressive (SP) course of pre-Tx IgAN (annual GFR > or <30 mL/min/1.73 m(2) ) was studied. Among 106 included patients, there were 14 graft losses giving a graft loss rate of 1.9/100 patient years. Follow-up until the first kidney transplant was 6.9 ± 4.4 (range 0.1-19) yr. Patients with pre-Tx RP had a higher graft loss rate compared with SP patients (6.3 vs.1.3/100 patient years, p < 0.001). Graft loss rate with living-related donor (LRD) was similar to unrelated donor (UD) grafts. Most RP patients had received LRD grafts, and in SP patients, graft survival with LRD grafts was better than UD grafts (0.3 vs.2.1/100 patient years, p = 0.055). A rapid pre-transplant course is a strong risk factor for transplant failure in patients with IgAN. © 2011 John Wiley & Sons A/S.

  8. Cell entry by a novel European filovirus requires host endosomal cysteine proteases and Niemann-Pick C1

    PubMed Central

    Ng, Melinda; Ndungo, Esther; Jangra, Rohit K.; Cai, Yingyun; Postnikova, Elena; Radoshitzky, Sheli R.; Dye, John M.; de Arellano, Eva Ramírez; Negredo, Ana; Palacios, Gustavo; Kuhn, Jens H.; Chandran, Kartik

    2014-01-01

    Lloviu virus (LLOV), a phylogenetically divergent filovirus, is the proposed etiologic agent of die-offs of Schreiber’s long-fingered bats (Miniopterus schreibersii) in western Europe. Studies of LLOV remain limited because the infectious agent has not yet been isolated. Here, we generated a recombinant vesicular stomatitis virus expressing the LLOV spike glycoprotein (GP) and used it to show that LLOV GP resembles other filovirus GP proteins in structure and function. LLOV GP must be cleaved by endosomal cysteine proteases during entry, but is much more protease-sensitive than EBOV GP. The EBOV/MARV receptor, Niemann Pick C1 (NPC1), is also required for LLOV entry, and its second luminal domain is recognized with high affinity by a cleaved form of LLOV GP, suggesting that receptor binding would not impose a barrier to LLOV infection of humans and non-human primates. The use of NPC1 as an intracellular entry receptor may be a universal property of filoviruses. PMID:25310500

  9. Aminopeptidase N1 (EtAPN1), an M1 Metalloprotease of the Apicomplexan Parasite Eimeria tenella, Participates in Parasite Development

    PubMed Central

    Gras, Simon; Byzia, Anna; Gilbert, Florence B.; McGowan, Sheena; Drag, Marcin; Niepceron, Alisson; Lecaille, Fabien; Lalmanach, Gilles; Brossier, Fabien

    2014-01-01

    Aminopeptidases N are metalloproteases of the M1 family that have been reported in numerous apicomplexan parasites, including Plasmodium, Toxoplasma, Cryptosporidium, and Eimeria. While investigating the potency of aminopeptidases as therapeutic targets against coccidiosis, one of the most important avian diseases caused by the genus Eimeria, we identified and characterized Eimeria tenella aminopeptidase N1 (EtAPN1). Its inhibition by bestatin and amastatin, as well as its reactivation by divalent ions, is typical of zinc-dependent metalloproteases. EtAPN1 shared a similar sequence, three-dimensional structure, and substrate specificity and similar kinetic parameters with A-M1 from Plasmodium falciparum (PfA-M1), a validated target in the treatment of malaria. EtAPN1 is synthesized as a 120-kDa precursor and cleaved into 96-, 68-, and 38-kDa forms during sporulation. Further, immunolocalization assays revealed that, similar to PfA-M1, EtAPN1 is present during the intracellular life cycle stages in both the parasite cytoplasm and the parasite nucleus. The present results support the hypothesis of a conserved role between the two aminopeptidases, and we suggest that EtAPN1 might be a valuable target for anticoccidiosis drugs. PMID:24839124

  10. Effects of High-Intensity Interval and Moderate-Intensity Continuous Exercise on Inflammatory, Leptin, IgA, and Lipid Peroxidation Responses in Obese Males.

    PubMed

    de Souza, Daniel C; Matos, Victor A F; Dos Santos, Victor O A; Medeiros, Italo F; Marinho, Cristiane S R; Nascimento, Paulo R P; Dorneles, Gilson P; Peres, Alessandra; Müller, Carlos H; Krause, Maurício; Costa, Eduardo C; Fayh, Ana P T

    2018-01-01

    Purpose: To compare the effects of a single high-intensity interval exercise session (HIIE) with a moderate-intensity continuous exercise session (MICE) on the inflammatory profile, IgA levels, and lipid peroxidation in sedentary obese males. Methods: Ten sedentary obese men (age 28.5 ± 2.7 years; BMI 35.9 ± 4.9 kg/m 2 ; body fat 40.6 ± 2.0%) performed three experimental sessions, on separate days with 1 week wash-out period between interventions, according to a randomized order: (1) HIIE: 10 × 60 s at 90% of the HR max alternated by 60 s of active recovery; (2) MICE: 20 min at 70% of the HR max; (3) Rest-control. Blood and saliva samples were collected before, immediately after and 60 min after the end of each session in order to analyse serum levels of cytokines, IgA, and lipoperoxidation markers. Results: Leptin levels decreased immediately after HIIE ( P = 0.033) and was different from the MICE ( P = 0.025). IFN-γ levels were reduced immediately after ( P = 0.032) and 60 min after HIIE ( P = 0.003) compared to baseline, and it also increased IL-4 levels immediately after exercise ( P = 0.007) compared to resting values. MICE promoted an increase in IFN-γ levels immediately after exercise ( P = 0.025) and 60 min after exercise ( P = 0.004) in relation to baseline. Both exercise conditions increased IL-6 levels up to 60 min after exercise ( P < 0.05). The IFN-γ/IL-4 ratio decreased immediately after ( P = 0.002) and 60 min after HIIE ( P = 0.005) in relation to pre-exercise. No changes were found for IgA-S and TBARS for any of the conditions. Conclusion: A single HIIE session is able to decrease IFN-γ/IL-4 ratio, indicating an anti-inflammatory response, without alterations in the function of the mucosal immune system and lipoperoxidation. On the other hand, a brief session of MICE induced changes in the pattern of cytokines associated with increased cellular immune function.

  11. Effects of High-Intensity Interval and Moderate-Intensity Continuous Exercise on Inflammatory, Leptin, IgA, and Lipid Peroxidation Responses in Obese Males

    PubMed Central

    de Souza, Daniel C.; Matos, Victor A. F.; dos Santos, Victor O. A.; Medeiros, Italo F.; Marinho, Cristiane S. R.; Nascimento, Paulo R. P.; Dorneles, Gilson P.; Peres, Alessandra; Müller, Carlos H.; Krause, Maurício; Costa, Eduardo C.; Fayh, Ana P. T.

    2018-01-01

    Purpose: To compare the effects of a single high-intensity interval exercise session (HIIE) with a moderate-intensity continuous exercise session (MICE) on the inflammatory profile, IgA levels, and lipid peroxidation in sedentary obese males. Methods: Ten sedentary obese men (age 28.5 ± 2.7 years; BMI 35.9 ± 4.9 kg/m2; body fat 40.6 ± 2.0%) performed three experimental sessions, on separate days with 1 week wash-out period between interventions, according to a randomized order: (1) HIIE: 10 × 60 s at 90% of the HRmax alternated by 60 s of active recovery; (2) MICE: 20 min at 70% of the HRmax; (3) Rest—control. Blood and saliva samples were collected before, immediately after and 60 min after the end of each session in order to analyse serum levels of cytokines, IgA, and lipoperoxidation markers. Results: Leptin levels decreased immediately after HIIE (P = 0.033) and was different from the MICE (P = 0.025). IFN-γ levels were reduced immediately after (P = 0.032) and 60 min after HIIE (P = 0.003) compared to baseline, and it also increased IL-4 levels immediately after exercise (P = 0.007) compared to resting values. MICE promoted an increase in IFN-γ levels immediately after exercise (P = 0.025) and 60 min after exercise (P = 0.004) in relation to baseline. Both exercise conditions increased IL-6 levels up to 60 min after exercise (P < 0.05). The IFN-γ/IL-4 ratio decreased immediately after (P = 0.002) and 60 min after HIIE (P = 0.005) in relation to pre-exercise. No changes were found for IgA-S and TBARS for any of the conditions. Conclusion: A single HIIE session is able to decrease IFN-γ/IL-4 ratio, indicating an anti-inflammatory response, without alterations in the function of the mucosal immune system and lipoperoxidation. On the other hand, a brief session of MICE induced changes in the pattern of cytokines associated with increased cellular immune function. PMID:29875681

  12. shRNA-Mediated Silencing of Y-Box Binding Protein-1 (YB-1) Suppresses Growth of Neuroblastoma Cell SH-SY5Y In Vitro and In Vivo

    PubMed Central

    Wang, Hong; Sun, Ruowen; Gu, Min; Li, Shuang; Zhang, Bin; Chi, Zuofei; Hao, Liangchun

    2015-01-01

    Y-box binding protein-1 (YB-1), a member of cold-shock protein superfamily, has been demonstrated to be associated with tumor malignancy, and is proposed as a prognostic marker in multiple carcinomas. However, the role of YB-1 in neuroblastoma has not been well studied. To investigate the functional role of YB-1 in neuroblastoma, we established a YB-1-silenced neuroblastoma cell strain by inhibiting YB-1 expression using a shRNA knockdown approach. YB-1-silenced neuroblastoma SH-SY5Y cells exhibited a pronounced reduction in cell proliferation and an increased rate of apoptosis in vitro and in vivo xenograft tumor model. At molecular level, YB-1 silencing resulted in downregulation of Cyclin A, Cyclin D1 and Bcl-2, as well as upregulated levels of Bax, cleaved caspase-3 and cleaved PARP-1. We further demonstrated that YB-1 transcriptionally regulated Cyclin D1 expression by chromatin-immunoprecipitation and luciferase reporter assays. In addition, xenograft tumors derived from neuroblastoma SH-SY5Y cell line were treated with YB-1 shRNA plasmids by intra-tumor injection, and YB-1 targeting effectively inhibited tumor growth and induced cell death. In summary, our findings suggest that YB-1 plays a critical role in neuroblastoma development, and it may serve as a potential target for neuroblastoma therapy. PMID:25993060

  13. Modeling of TREX1-Dependent Autoimmune Disease using Human Stem Cells Highlights L1 Accumulation as a Source of Neuroinflammation.

    PubMed

    Thomas, Charles A; Tejwani, Leon; Trujillo, Cleber A; Negraes, Priscilla D; Herai, Roberto H; Mesci, Pinar; Macia, Angela; Crow, Yanick J; Muotri, Alysson R

    2017-09-07

    Three-prime repair exonuclease 1 (TREX1) is an anti-viral enzyme that cleaves nucleic acids in the cytosol, preventing accumulation and a subsequent type I interferon-associated inflammatory response. Autoimmune diseases, including Aicardi-Goutières syndrome (AGS) and systemic lupus erythematosus, can arise when TREX1 function is compromised. AGS is a neuroinflammatory disorder with severe and persistent intellectual and physical problems. Here we generated a human AGS model that recapitulates disease-relevant phenotypes using pluripotent stem cells lacking TREX1. We observed abundant extrachromosomal DNA in TREX1-deficient neural cells, of which endogenous Long Interspersed Element-1 retrotransposons were a major source. TREX1-deficient neurons also exhibited increased apoptosis and formed three-dimensional cortical organoids of reduced size. TREX1-deficient astrocytes further contributed to the observed neurotoxicity through increased type I interferon secretion. In this model, reverse-transcriptase inhibitors rescued the neurotoxicity of AGS neurons and organoids, highlighting their potential utility in therapeutic regimens for AGS and related disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. The TRPM7 chanzyme is cleaved to release a chromatin modifying kinase

    PubMed Central

    Krapivinsky, Grigory; Krapivinsky, Luba; Manasian, Yunona; Clapham, David E.

    2014-01-01

    SUMMARY TRPM7 is a ubiquitous ion channel and kinase, a unique ‘chanzyme’, required for proper early embryonic development. It conducts Zn2+, Mg2+, Ca2+ as well as monovalent cations, and contains a functional serine/threonine kinase at its carboxyl terminus. Here, we show that in normal tissues and cell lines, the kinase is proteolytically cleaved from the channel domain in a cell type-specific manner. These TRPM7 Cleaved Kinase fragments (M7CKs) translocate to the nucleus and bind multiple components of chromatin remodeling complexes, including Polycomb group proteins. In the nucleus, the kinase phosphorylates specific serines/threonines of histones. M7CK-dependent phosphorylation of H3Ser10 at promoters of TRPM7-dependent genes correlates with their activity. We also demonstrate that cytosolic free [Zn2+] is TRPM7-dependent and regulates M7CK binding to transcription factors containing zinc-finger domains. These findings suggest that TRPM7-mediated modulation of intracellular Zn2+ concentration couples ion channel signaling to epigenetic chromatin covalent modifications that affect gene expression patterns. PMID:24855944

  15. Purification of an IgA Monoclonal Antibody Specific for the Acr Protein of Mycobacterium tuberculosis by Immunoaffinity Chromatography

    PubMed Central

    REYES, Fátima; OTERO, Oscar; CAMACHO, Frank; SARMIENTO, María Elena; ACOSTA, Armando

    2013-01-01

    Background: A monoclonal antibody (mAb) of the IgA isotype, designated TBA61, is specific for the Acr protein of Mycobacterium tuberculosis (MTB). TBA61 has been used in studies exploring protection against tuberculosis (TB), and its efficacy has been proven using different challenge models. To purify the mouse IgA isotype, a combination of methods, such as globulin precipitation, ion exchange, and gel filtration, is usually required to achieve a satisfactory degree of purity. Methods: To minimise the number of chromatographic steps, we proposed to employ immunoaffinity chromatography using the Acr protein of MTB as a specific ligand for this mAb. For this purpose, the HspX gene was cloned and expressed in Escherichia coli, and recombinant Acr (rAcr) was coupled to a cyanogen bromide-activated Sepharose 4B matrix, which was used to purify TBA61 mAb from ascites produced in mice in a single step. Results: The recovery from the purification procedure was 1.46 mg per mL of ascites. Analysis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot showed a high purity. The purified mAb retained its reactivity against the Acr protein based on enzyme-linked immunosorbent assay (ELISA) and western blot. Conclusion: The purification method used is rapid, simple, and specific and can be easily scaled up. PMID:24643305

  16. HIV-1 Infection Induces Interleukin-1β Production via TLR8 Protein-dependent and NLRP3 Inflammasome Mechanisms in Human Monocytes*

    PubMed Central

    Guo, Haitao; Gao, Jianmei; Taxman, Debra J.; Ting, Jenny P. Y.; Su, Lishan

    2014-01-01

    The induction of inflammatory cytokines such as IL-1β is associated with the progression of human immunodeficiency virus, type 1 (HIV-1) disease or AIDS. Unlike most inflammatory cytokines that are regulated by NF-κB at the transcriptional level, production of mature IL-1β also depends on inflammasome activation. The mechanism by which HIV-1 induces pro-IL-1β expression and activates inflammasomes to cleave pro-IL-1β into its bioactive form is not clearly defined. We report here that HIV-1 infection in human monocytes efficiently induced IL-1β expression and inflammasome activation. Toll-like receptor 8 (TLR8) was required for inducing pro-IL-1β expression, whereas the NLRP3 inflammasome was required for IL-1β maturation and release. Furthermore, the lysosomal protease cathepsin B and HIV-1 induced production of reactive oxygen species were critical for HIV-induced inflammasome activation and IL-1β production. HIV-1 entry, reverse transcription, and integration were all required for both pro-IL-1β expression and inflammasome activation. Finally, we show that HIV-1-derived RNA was sufficient to induce both pro-IL-1β expression and inflammasome activation. We conclude that HIV-1 infection induced the expression of pro-IL-1β via TLR8-mediated mechanisms and activated caspase-1 through the NLRP3 inflammasome to cleave pro-IL-1β into bioactive IL-1β. These findings help to elucidate mechanisms of HIV-1 disease progression and identify novel targets for treating HIV-1 induced inflammation and immune activation. PMID:24939850

  17. Protection against Foot-and-Mouth Disease Virus in Guinea Pigs via Oral Administration of Recombinant Lactobacillus plantarum Expressing VP1

    PubMed Central

    Wang, Miao; Pan, Li; Zhou, Peng; Lv, Jianliang; Zhang, Zhongwang; Wang, Yonglu; Zhang, Yongguang

    2015-01-01

    Mucosal vaccination is an effective strategy for generating antigen-specific immune responses against mucosal infections of foot-and-mouth disease virus (FMDV). In this study, Lactobacillus plantarum strains NC8 and WCFS1 were used as oral delivery vehicles containing a pSIP411-VP1 recombinant plasmid to initiate mucosal and systemic immune responses in guinea pigs. Guinea pigs were orally vaccinated (three doses) with NC8-pSIP411, NC8-pSIP411-VP1, WCFS1-pSIP411, WCFS1-pSIP411-VP1 or milk. Animals immunized with NC8-pSIP411-VP1 and WCFS1-pSIP411-VP1 developed high levels of antigen-specific serum IgG, IgA, IgM, mucosal secretory IgA (sIgA) and neutralizing antibodies, and revealed stronger cell-mediated immune responses and enhanced protection against FMDV challenge compared with control groups. The recombinant pSIP411-VP1 effectively improved immunoprotection against FMDV in guinea pigs. PMID:26629822

  18. Structural Analysis of a Family 81 Glycoside Hydrolase Implicates Its Recognition of β-1,3-Glucan Quaternary Structure.

    PubMed

    Pluvinage, Benjamin; Fillo, Alexander; Massel, Patricia; Boraston, Alisdair B

    2017-09-05

    Family 81 glycoside hydrolases (GHs), which are known to cleave β-1,3-glucans, are found in archaea, bacteria, eukaryotes, and viruses. Here we examine the structural and functional features of the GH81 catalytic module, BhGH81, from the Bacillus halodurans protein BH0236 to probe the molecular basis of β-1,3-glucan recognition and cleavage. BhGH81 displayed activity on laminarin, curdlan, and pachyman, but not scleroglucan; the enzyme also cleaved β-1,3-glucooligosaccharides as small as β-1,3-glucotriose. The crystal structures of BhGH81 in complex with various β-1,3-glucooligosaccharides revealed distorted sugars in the -1 catalytic subsite and an arrangement consistent with an inverting catalytic mechanism having a proposed conformational itinerary of 2 S 0 → 2,5 B ‡ → 5 S 1 . Notably, the architecture of the catalytic site, location of an adjacent ancillary β-1,3-glucan binding site, and the surface properties of the enzyme indicate the likely ability to recognize the double and/or triple-helical quaternary structures adopted by β-1,3-glucans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Impaired Antibody-mediated Protection and Defective IgA B-Cell Memory in Experimental Infection of Adults with Respiratory Syncytial Virus.

    PubMed

    Habibi, Maximillian S; Jozwik, Agnieszka; Makris, Spyridon; Dunning, Jake; Paras, Allan; DeVincenzo, John P; de Haan, Cornelis A M; Wrammert, Jens; Openshaw, Peter J M; Chiu, Christopher

    2015-05-01

    Despite relative antigenic stability, respiratory syncytial virus (RSV) reinfects throughout life. After more than 40 years of research, no effective human vaccine exists and correlates of protection remain poorly defined. Most current vaccine candidates seek to induce high levels of RSV-specific serum neutralizing antibodies, which are associated with reduced RSV-related hospitalization rates in observational studies but may not actually prevent infection. To characterize correlates of protection from infection and the generation of RSV-specific humoral memory to promote effective vaccine development. We inoculated 61 healthy adults with live RSV and studied protection from infection by serum and mucosal antibody. We analyzed RSV-specific peripheral blood plasmablast and memory B-cell frequencies and antibody longevity. Despite moderately high levels of preexisting serum antibody, 34 (56%) became infected, of whom 23 (68%) developed symptomatic colds. Prior RSV-specific nasal IgA correlated significantly more strongly with protection from polymerase chain reaction-confirmed infection than serum neutralizing antibody. Increases in virus-specific antibody titers were variable and transient in infected subjects but correlated with plasmablasts that peaked around Day 10. During convalescence, only IgG (and no IgA) RSV-specific memory B cells were detectable in peripheral blood. This contrasted with natural influenza infection, in which virus-specific IgA memory B cells were readily recovered. This observed specific defect in IgA memory may partly explain the ability of RSV to cause recurrent symptomatic infections. If so, vaccines able to induce durable RSV-specific IgA responses may be more protective than those generating systemic antibody alone.

  20. Towards Universal Screening for Toxoplasmosis: Rapid, Cost-effective and Simultaneous Detection of Toxoplasma Anti-IgG, IgM and IgA Antibodies Using Very Small Serum Volumes

    EPA Pesticide Factsheets

    No dataset associated with this publication.This dataset is associated with the following publication:Augustine, S. Towards Universal Screening for Toxoplasmosis: Rapid, Cost-effective and Simultaneous Detection of Toxoplasma Anti-IgG, IgM and IgA Antibodies Using Very Small Serum Volumes. JOURNAL OF CLINICAL MICROBIOLOGY. American Society for Microbiology, Washington, DC, USA, 56(7): 1-2, (2016).

  1. Correlation between serum levels of vitamin B12 and anti-Helicobacter pylori IgA antibodies in vitamin B12 deficient Palestinian patients.

    PubMed

    Abu Hilu, Rasmi; Dudeen, Osama; Barghouthi, Sameer Abdullatif

    2015-01-01

    H. pylori infection and vitamin B12 (vB12) deficiency have high prevalence rates among Palestinians. It was observed that most people who suffered from vB12 deficiency were positive for H. pylori. The correlation between H. pylori infection and vB12 deficiency was investigated in a representative segment of the Palestinian population. ELISA was used to determine levels of vitamin B12 (vB12) and anti-H. pylori IgA in sera from 238 participants from Al-Khalil district (Hebron), Palestine. There was a strong negative Pearson's correlation coefficient (r = -0.45; P = 0.00001) between levels of anti-H. pylori IgA and vB12 levels in sera drawn from 238 participants (133 patients and 105 control subjects). Two important contaminating variables were identified in this study: healthy control subjects with elevated anti-H. pylori IgA titers and vB12-deficient patients testing negative for anti-H. pylori IgA antibodies. The exclusion of the sources of contamination resulted in a stronger negative correlation; r = -0.58 (P = 0.00001). The study provided a good screening system that may predict vB12 deficiency before its actual manifestation. If not treated, asymptomatic subjects showing increased anti-H.pylori IgA titers (> 15 NTU/mL) are likely to be at risk of developing vB12 deficiency.

  2. Lacrimal secretory IgA in active posterior uveitis induced by Toxoplasma gondii.

    PubMed

    Lynch, Maria Isabel; Cordeiro, Francisco; Ferreira, Silvana; Ximenes, Ricardo; Oréfice, Fernando; Malagueño, Elizabeth

    2004-12-01

    It is quite difficult to diagnose active toxoplasmosis in patients with ocular toxoplasmosis. Active posterior uveitis presumably due to Toxoplasma gondii infection (APUPT) is seldom produced during a prime-infection; hence most patients do not show high IgM antibodies. High levels of IgA have been described in active toxoplasmosis. The purpose of this study was to investigate possible association between APUPT and the specific anti-parasite sIgA in tears. The study was carried out as case-control. Tears of 25 clinically confirmed APUPT patients and 50 healthy control subjects were analyzed. All were IgG seropositive. Specific sIgA was determined by ELISA assay using T. gondii RH strain crude extract. Anti-T. gondii sIgA was found in 84% of the cases and in 22% of the control subjects. The intensity of the reaction was higher in APUPT cases (P = 0.007). There was strong association between APUPT patients and lacrimal sIgA (odds-ratio 18.61, P = 0.0001). ELISA test sensitivity was 84% and specificity 78%. Our data suggest that anti-T.gondii secretory IgA found in tears may become an important marker for active ocular toxoplasmosis.

  3. Predicting Post-Transplant Recurrence of IgA Nephropathy: The Importance of Crescents.

    PubMed

    Avasare, Rupali S; Rosenstiel, Paul E; Zaky, Ziad S; Tsapepas, Demetra S; Appel, Gerald B; Markowitz, Glen S; Bomback, Andrew S; Canetta, Pietro A

    2017-01-01

    Most studies that have assessed the predictors of recurrent IgA nephropathy (IgAN) in the renal allograft have focused on post-transplant features. Identifying high-risk pre-transplant features of IgAN is useful for counseling patients and may help in tailoring post-transplant immunosuppression. We investigated the pre-transplant clinical and biopsy features of 62 patients with IgAN who received transplants at Columbia University Medical Center from 2001 to 2012 and compared the characteristics and outcomes of patients with IgAN recurrence to those without recurrence. The primary outcome was time to recurrent IgAN. Secondary outcomes were a composite of doubling of creatinine or allograft failure, and recurrent IgAN as a cause of allograft dysfunction. Of the 62 patients, 14 had recurrent IgAN in the allograft. Mean time to recurrence was 2.75 years. Those with recurrent disease were younger at the time of native kidney biopsy (29 vs. 41 years, p < 0.0009). Black race and Hispanic ethnicity composed a higher proportion of the recurrent disease group. On multivariable analysis, significant predictors of recurrent IgAN included age at diagnosis (hazards ratio (HR) 0.911, 95% CI 0.85-0.98), burden of crescents on native biopsy (HR 1.21 per 10% increase in crescents, 95% CI 1.00-1.47) and allograft rejection (HR 3.59, 95% CI 1.10-11.7). Features of native IgAN can help predict the risk of recurrent disease in the renal allograft. In particular, immunologically active disease represented by earlier age of onset and greater burden of crescents on native biopsy is more likely to recur after transplant. © 2017 S. Karger AG, Basel.

  4. Patients with IgA nephropathy exhibit high systemic PDGF-DD levels.

    PubMed

    Boor, Peter; Eitner, Frank; Cohen, Clemens D; Lindenmeyer, Maja T; Mertens, Peter R; Ostendorf, Tammo; Floege, Jürgen

    2009-09-01

    Platelet-derived growth factor (PDGF) is a central mediator of mesangioproliferative glomerulonephritis (GN). In experimental mesangioproliferative GN, PDGF-DD serum levels, unlike PDGF-BB, increased up to 1000-fold. We assessed disease activity in 72 patients with GN, established a novel PDGF-D ELISA and then determined their PDGF-DD levels. In parallel, we studied renal PDGF-DD mRNA expression by RT-PCR. PDGF-DD serum levels in patients with IgA nephropathy (IgAN) were significantly higher (1.67 +/- 0.45 ng/ml) and in patients with lupus nephritis significantly lower (0.66 +/- 0.86 ng/ml) compared to healthy controls (1.17 +/- 0.46 ng/ml), while patients with focal segmental glomerulosclerosis, membranous GN and ANCA-positive vasculitis did not differ from controls. The subgroup of IgAN patients with elevated PDGF-DD levels (27% of samples) did not differ in their clinical features from those with normal PDGF-DD levels. In IgAN patients with repetitive PDGF-DD determinations, most exhibited only minor fluctuations of serum levels over time. Intrarenal PDGF-DD mRNA expression did not differ between controls and patients, suggesting an extrarenal source of the elevated PDGF-DD in IgAN. Serum PDGF-DD levels were specifically elevated in patients with IgAN, in particular in those with early disease, i.e. preserved renal function. Our data support the rationale for anti-PDGF-DD therapy in mesangioproliferative GN.

  5. Comparative study on the development of intestinal mucin 2, IgA and polymeric Ig receptor expressions between broiler chickens and Pekin ducks

    USDA-ARS?s Scientific Manuscript database

    Intestinal mucin2 (MUC2), a major gel-forming mucin, represents a primary barrier component of mucus layers and target site for secretory IgA. Polymeric Ig receptor (pIgR) expressed on the basolateral surface of epithelium, is used to transport polymeric IgA from the lamina propria into luminal muci...

  6. Moderate acute exercise (70% VO2 peak) induces TGF-β, α-amylase and IgA in saliva during recovery.

    PubMed

    Rosa, L; Teixeira, Aas; Lira, Fs; Tufik, S; Mello, Mt; Santos, Rvt

    2014-03-01

    Strenuous exercise promotes changes in salivary IgA and can be associated with a high incidence of upper respiratory tract Infections. However, moderate exercise enhances immune function. The effect of exercise on salivary IgA has been well studied, but its effect on other immunological parameters is poorly studied. Thus, this study determined the effect of moderate acute exercise on immunological salivary parameters, such as the levels of cytokines (TGF-β and IL-5), IgA, α-amylase and total protein, over 24 h. Ten male adult subjects exercised for 60 min at an intensity of 70% VO2 peak. Saliva samples were collected before ('basal') and 0, 12 and 24 h after an exercise session. The total salivary protein was lower after 12 and 24 h than immediately after exercise, whereas α-amylase increased at 12 and 24 h after exercise compared with basal levels. The IgA concentration was increased at 24 h after exercise relative to immediately after exercise, and there was no difference in the IL-5 while TGF-β concentration increased in recovery. In conclusion, 70% VO2 peak exercise does not induce changes immediately after exercise, but after 24 h, it produces an increase in salivary TGF-β without changing IL-5. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. PrP(C) homodimerization stimulates the production of PrPC cleaved fragments PrPN1 and PrPC1.

    PubMed

    Béland, Maxime; Motard, Julie; Barbarin, Alice; Roucou, Xavier

    2012-09-19

    An endoproteolytic cleavage termed α-cleavage between residues 111/112 is a characteristic feature of the cellular prion protein (PrP(C)). This cleavage generates a soluble N-terminal fragment (PrPN1) and a glycosylphosphatidylinositol-anchored C-terminal fragment (PrPC1). Independent studies demonstrate that modulating PrP(C) α-cleavage represents a potential therapeutic strategy in prion diseases. The regulation of PrP(C) α-cleavage is unclear. The only known domain that is essential for the α-cleavage to occur is a hydrophobic domain (HD). Importantly, the HD is also essential for the formation of PrP(C) homodimers. To explore the role of PrP(C) homodimerization on the α-cleavage, we used a well described inducible dimerization strategy whereby a chimeric PrP(C) composed of a modified FK506-binding protein (Fv) fused with PrP(C) and termed Fv-PrP is incubated in the presence of a dimerizer AP20187 ligand. We show that homodimerization leads to a considerable increase of PrP(C) α-cleavage in cultured cells and release of PrPN1 and PrPC1. Interestingly, enforced homodimerization increased PrP(C) levels at the plasma membrane, and preventing PrP(C) trafficking to the cell surface inhibited dimerization-induced α-cleavage. These observations were confirmed in primary hippocampal neurons from transgenic mice expressing Fv-PrP. The proteases responsible for the α-cleavage are still elusive, and in contrast to initial studies we confirm more recent investigations that neither ADAM10 nor ADAM17 are involved. Importantly, PrPN1 produced after PrP(C) homodimerization protects against toxic amyloid-β (Aβ) oligomers. Thus, our results show that PrP(C) homodimerization is an important regulator of PrP(C) α-cleavage and may represent a potential therapeutic avenue against Aβ toxicity in Alzheimer's disease.

  8. Migration of antigen-presenting B cells from peripheral to mucosal lymphoid tissues may induce intestinal antigen-specific IgA following parenteral immunization.

    PubMed

    Coffin, S E; Clark, S L; Bos, N A; Brubaker, J O; Offit, P A

    1999-09-15

    Parenterally administered immunizations have long been used to induce protection from mucosal pathogens such as Bordetella pertussis and influenza virus. We previously found that i.m. inoculation of mice with the intestinal pathogen, rotavirus, induced virus-specific Ab production by intestinal lymphocytes. We have now used adoptive transfer studies to identify the cell types responsible for the generation of virus-specific Ab production by gut-associated lymphoid tissue (GALT) after i.m. immunization. Three days after i.m. immunization with rotavirus, cells obtained from the draining peripheral lymph nodes of donor mice were transferred into naive recipient mice. We found that intestinal lymphocytes produced rotavirus-specific Igs (IgM, IgA, and IgG) 2 wk after transfer of either unfractionated cells, or unfractionated cells rendered incapable of cellular division by mitomycin C treatment. Additional studies demonstrated that rotavirus-specific IgA, but not IgG, was produced by intestinal lymphocytes after transfer of purified B cells. Ig allotype analysis revealed that rotavirus-specific IgA was produced by intestinal B cells of recipient origin, suggesting that migration of Ag-presenting B cells from peripheral lymphoid tissues to GALT may contribute to the generation of mucosal IgA responses after parenteral immunization. Strategies that promote Ag uptake and presentation by B cells may enhance mucosal IgA production following parenteral immunization.

  9. Effect of timing of development on total cell number and expression profile of HSP-70.1 and GLUT-1 in buffalo (Bubalus bubalis) oocytes and preimplantation embryos produced in vitro.

    PubMed

    Rajhans, Rajib; Kumar, G Sai; Dubey, Pawan K; Sharma, G Taru

    2010-03-29

    The present study was designed to compare the expression profile of two developmentally important genes (HSP-70.1 and GLUT-1) and TCN (total cell number) count in fast (group A) and slow (group B) cleaved buffalo embryos to access their in vitro developmental competence. Buffalo COCs (cumulus oocyte complexes) were collected from local abattoir ovaries and subjected to in vitro maturation in: TCM-199 supplemented with 10% FBS (fetal bovine serum), BSA (3 mg/ml), sodium pyruvate (0.25 mM) and 20 ng/ml EGF (epidermal growth factor) at 38.5 degrees C under 5% CO2. In vitro derived embryos were collected at 4-8, 8-16 cell, morula and blastocyst stages at specific time points for gene expression analysis and total cell count. A semiquantitative RT-PCR (reverse transcriptase-PCR) assay was used to determine the HSP-70.1 and GLUT-1 transcripts. Results showed that developmental competence and TCN count in fast (group A)-cleaving embryos was significantly (P<0.05) higher than in the slow group (group B). The gene transcript of HSP-70.1 and GLUT-1 was expressed in oocytes (immature and mature) and throughout the embryonic developmental stages in the fast group (group A), while in the slow (group B) cleaving embryos, the expression of HSP-70.1 was absent in all the embryonic developmental stages, and expression of GLUT-1 was absent after 8-16 cell stage. In conclusion, TCN count and expression profile of HSP-70.1 and GLUT-1 genes in buffalo embryos are different taking into account the cleavage rate. Quality of such embryos for research purposes, TCN and expression profiling of developmentally important genes should be employed to optimize the in vitro culture system to produce superior quality of embryos.

  10. IgA deficiency in wolves from Canada and Scandinavia.

    PubMed

    Frankowiack, Marcel; Olsson, Mia; Cluff, H Dean; Evans, Alina L; Hellman, Lars; Månsson, Johan; Arnemo, Jon M; Hammarström, Lennart

    2015-05-01

    Immunoglobulin A deficiency (IgAD) is the most common primary immunodeficiency in both humans and selected breeds of domestic dogs. In both species, IgAD is associated with recurrent infections and immune mediated diseases. Previous results imply that IgAD is also common in the wild ancestor of domestic dogs, the gray wolf. Here, we report that serum IgA concentrations are significantly different in Scandinavian and Canadian wolves (p = 3.252e-15) with an increased prevalence for IgAD in Scandinavian wolves (60%), which is as high as those found in high-risk dog breeds. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Differential restriction patterns of mRNA decay factor AUF1 during picornavirus infections.

    PubMed

    Cathcart, Andrea L; Semler, Bert L

    2014-07-01

    During infection by picornaviruses, the cellular environment is modified to favour virus replication. This includes the modification of specific host proteins, including the recently discovered viral proteinase cleavage of mRNA decay factor AU-rich binding factor 1 (AUF1). This cellular RNA-binding protein was shown previously to act as a restriction factor during poliovirus, rhinovirus and coxsackievirus infection. During infection by these viruses, AUF1 relocalizes to the cytoplasm and is cleaved by the viral 3C/3CD proteinase. In this study, we demonstrated that replication of encephalomyocarditis virus (EMCV), a picornavirus belonging to the genus Cardiovirus, is AUF1 independent. During EMCV infection, AUF1 relocalized to the cytoplasm; however, unlike what is seen during enterovirus infections, AUF1 was not cleaved to detectable levels, even at late times after infection. This suggests that AUF1 does not act broadly as an inhibitor of picornavirus infections but may instead act as a selective restriction factor targeting members of the genus Enterovirus. © 2014 The Authors.

  12. Incorporation of the catalytic domain of a hammerhead ribozyme into antisense RNA enhances its inhibitory effect on the replication of human immunodeficiency virus type 1.

    PubMed Central

    Homann, M; Tzortzakaki, S; Rittner, K; Sczakiel, G; Tabler, M

    1993-01-01

    The catalytic domain of a hammerhead ribozyme was incorporated into a 413 nucleotides long antisense RNA directed against the 5'-leader/gag region of the human immunodeficiency virus type 1 (HIV-1) (pos. +222 to +634). The resulting catalytic antisense RNA was shown to cleave its target RNA in vitro specifically at physiological ion strength and temperature. We compared the antiviral effectiveness of this catalytic antisense RNA with that of the corresponding unmodified antisense RNA and with a mutated catalytic antisense RNA, which did not cleave the substrate RNA in vitro. Each of these RNAs was co-transfected into human SW480 cells together with infectious complete proviral HIV-1 DNA, followed by analysis of HIV-1 replication. The presence of the catalytically active domain resulted in 4 to 7 fold stronger inhibition of HIV-1 replication as compared to the parental antisense RNA and the inactive mutant. Kinetic and structural studies performed in vitro indicated that the ability for double strand formation was not changed in catalytic antisense RNA versus parental antisense RNA. Together, these data suggest that the ability to cleave target RNA is a crucial prerequisite for the observed increase of inhibition of the replication of HIV-1. Images PMID:8332489

  13. Discovery of new risk loci for IgA nephropathy implicates genes involved in immunity against intestinal pathogens

    PubMed Central

    Kiryluk, Krzysztof; Li, Yifu; Scolari, Francesco; Sanna-Cherchi, Simone; Choi, Murim; Verbitsky, Miguel; Fasel, David; Lata, Sneh; Prakash, Sindhuri; Shapiro, Samantha; Fischman, Clara; Snyder, Holly J.; Appel, Gerald; Izzi, Claudia; Viola, Battista Fabio; Dallera, Nadia; Vecchio, Lucia Del; Barlassina, Cristina; Salvi, Erika; Bertinetto, Francesca Eleonora; Amoroso, Antonio; Savoldi, Silvana; Rocchietti, Marcella; Amore, Alessandro; Peruzzi, Licia; Coppo, Rosanna; Salvadori, Maurizio; Ravani, Pietro; Magistroni, Riccardo; Ghiggeri, Gian Marco; Caridi, Gianluca; Bodria, Monica; Lugani, Francesca; Allegri, Landino; Delsante, Marco; Maiorana, Mariarosa; Magnano, Andrea; Frasca, Giovanni; Boer, Emanuela; Boscutti, Giuliano; Ponticelli, Claudio; Mignani, Renzo; Marcantoni, Carmelita; Di Landro, Domenico; Santoro, Domenico; Pani, Antonello; Polci, Rosaria; Feriozzi, Sandro; Chicca, Silvana; Galliani, Marco; Gigante, Maddalena; Gesualdo, Loreto; Zamboli, Pasquale; Maixnerová, Dita; Tesar, Vladimir; Eitner, Frank; Rauen, Thomas; Floege, Jürgen; Kovacs, Tibor; Nagy, Judit; Mucha, Krzysztof; Pączek, Leszek; Zaniew, Marcin; Mizerska-Wasiak, Małgorzata; Roszkowska-Blaim, Maria; Pawlaczyk, Krzysztof; Gale, Daniel; Barratt, Jonathan; Thibaudin, Lise; Berthoux, Francois; Canaud, Guillaume; Boland, Anne; Metzger, Marie; Panzer, Ulf; Suzuki, Hitoshi; Goto, Shin; Narita, Ichiei; Caliskan, Yasar; Xie, Jingyuan; Hou, Ping; Chen, Nan; Zhang, Hong; Wyatt, Robert J.; Novak, Jan; Julian, Bruce A.; Feehally, John; Stengel, Benedicte; Cusi, Daniele; Lifton, Richard P.; Gharavi, Ali G.

    2014-01-01

    We performed a genome-wide association study (GWAS) of IgA nephropathy (IgAN), the most common form of glomerulonephritis, with discovery and follow-up in 20,612 individuals of European and East Asian ancestry. We identified six novel genome-wide significant associations, four in ITGAM-ITGAX, VAV3 and CARD9 and two new independent signals at HLA-DQB1 and DEFA. We replicated the nine previously reported signals, including known SNPs in the HLA-DQB1 and DEFA loci. The cumulative burden of risk alleles is strongly associated with age at disease onset. Most loci are either directly associated with risk of inflammatory bowel disease (IBD) or maintenance of the intestinal epithelial barrier and response to mucosal pathogens. The geo-spatial distribution of risk alleles is highly suggestive of multi-locus adaptation and the genetic risk correlates strongly with variation in local pathogens, particularly helminth diversity, suggesting a possible role for host-intestinal pathogen interactions in shaping the genetic landscape of IgAN. PMID:25305756

  14. Antihistone Properties of C1 Esterase Inhibitor Protect against Lung Injury.

    PubMed

    Wygrecka, Malgorzata; Kosanovic, Djuro; Wujak, Lukasz; Reppe, Katrin; Henneke, Ingrid; Frey, Helena; Didiasova, Miroslava; Kwapiszewska, Grazyna; Marsh, Leigh M; Baal, Nelli; Hackstein, Holger; Zakrzewicz, Dariusz; Müller-Redetzky, Holger C; de Maat, Steven; Maas, Coen; Nolte, Marc W; Panousis, Con; Schermuly, Ralph T; Seeger, Werner; Witzenrath, Martin; Schaefer, Liliana; Markart, Philipp

    2017-07-15

    Acute respiratory distress syndrome is characterized by alveolar epithelial cell injury, edema formation, and intraalveolar contact phase activation. To explore whether C1 esterase inhibitor (C1INH), an endogenous inhibitor of the contact phase, may protect from lung injury in vivo and to decipher the possible underlying mechanisms mediating protection. The ability of C1INH to control the inflammatory processes was studied in vitro and in vivo. Here, we demonstrate that application of C1INH alleviates bleomycin-induced lung injury via direct interaction with extracellular histones. In vitro, C1INH was found to bind all histone types. Interaction with histones was independent of its protease inhibitory activity, as demonstrated by the use of reactive-center-cleaved C1INH, but dependent on its glycosylation status. C1INH sialylated-N- and -O-glycans were not only essential for its interaction with histones but also to protect against histone-induced cell death. In vivo, histone-C1INH complexes were detected in bronchoalveolar lavage fluid from patients with acute respiratory distress syndrome and multiple models of lung injury. Furthermore, reactive-center-cleaved C1INH attenuated pulmonary damage evoked by intravenous histone instillation. Collectively, C1INH administration provides a new therapeutic option for disorders associated with histone release.

  15. InhA1-Mediated Cleavage of the Metalloprotease NprA Allows Bacillus cereus to Escape From Macrophages.

    PubMed

    Haydar, Abbass; Tran, Seav-Ly; Guillemet, Elisabeth; Darrigo, Claire; Perchat, Stéphane; Lereclus, Didier; Coquet, Laurent; Jouenne, Thierry; Ramarao, Nalini

    2018-01-01

    Bacillus cereus is a Gram-positive spore-forming bacterium causing food poisoning and serious opportunistic infections. These infections are characterized by bacterial accumulation in the host despite the induction of inflammation. To circumvent inflammation, bacteria must resist the bactericidal activity of professional phagocytes, which constitute a first line of host defense against pathogens. Interactions between phagocytic cells and B. cereus are still poorly characterized and the mechanism of resistance to the host immune system is not known yet. We have previously shown that the spores are phagocytosed by macrophages but survive and escape from these cells. The metalloprotease InhA1 is a key effector involved in these processes. inhA1 -deficient spores are retained intracellularly, in contrast to the wild type strain spores. NprA is also a B. cereus metalloprotease able to cleave tissue components such as fibronectin, laminin, and collagen. Here, we show that NprA, concomitantly secreted with InhA1 in the B. cereus secretome, is essential to promote bacterial escape from macrophages. We show that InhA1 cleaves NprA at specific sites. This cleavage allows liberation of the mature form of the NprA protein in the supernatant of the wild type strain. This mature form of NprA is actually the principal effector allowing bacterial escape from host macrophages.

  16. Platelet endothelial cell adhesion molecule 1 deficiency misguides venous thrombus resolution.

    PubMed

    Kellermair, Joerg; Redwan, Bassam; Alias, Sherin; Jabkowski, Joerg; Panzenboeck, Adelheid; Kellermair, Lukas; Winter, Max P; Weltermann, Ansgar; Lang, Irene M

    2013-11-07

    Platelet endothelial cell adhesion molecule 1 (PECAM-1) is involved in leukocyte migration and angiogenesis, which are key components of venous thrombus resolution. This study investigated the effect of PECAM-1 deficiency on thrombus resolution in FVB/n mice and the extent to which levels of soluble PECAM-1 (sPECAM-1) correlate with delayed thrombus resolution in humans after acute symptomatic deep vein thrombosis (DVT). In a mouse stagnant flow venous thrombosis model Pecam-1(-/-) thrombi were larger, persisted for longer periods of time, and displayed attenuated macrophage invasion and decreased vessel formation in the presence of increased fibrosis. In humans, higher levels of truncated plasma sPECAM-1 possibly cleaved from cell surfaces, were found in patients with delayed thrombus resolution (assessed via duplex-based thrombus scoring) relative to those whose thrombi resolved (median, 25th/75th percentile): 92.5 (87.7/103.4) ng/mL vs 71.5 (51.1/81.0) ng/mL; P < .001. Furthermore, unresolved human deep vein thrombus specimens stained positively with antibodies specific for the extracellular, but not the cytoplasmic domain of PECAM-1, consistent with accumulation of cleaved PECAM-1. Our data suggest a regulatory role of PECAM-1 in venous thrombus resolution and suggest a predictive value of sPECAM-1 for postthrombotic syndrome (PTS) after acute DVT.

  17. An avirulent Brachyspira hyodysenteriae strain elicits intestinal IgA and slows down spread of swine dysentery.

    PubMed

    Mahu, Maxime; Boyen, Filip; Canessa, Stefano; Zavala Marchan, Jackeline; Haesebrouck, Freddy; Martel, An; Pasmans, Frank

    2017-10-05

    Swine dysentery caused by Brachyspira hyodysenteriae, results in substantial economic losses in swine producing countries worldwide. Although a number of different vaccine approaches have been explored with regard to this disease, they show limitations and none of them have reached the market. We here determine the vaccine potential of a weakly haemolytic B. hyodysenteriae strain. The virulence of this strain was assessed in experimental infection trials and its protection against swine dysentery was quantified in a vaccination-challenge experiment using a seeder infection model. Systemic IgG production and local IgA production were monitored in serum and faeces respectively. Across all trials, pigs that were colonized by virulent, strongly haemolytic B. hyodysenteriae strains consistently developed swine dysentery, in contrast to none of the pigs colonized by the weakly haemolytic B. hyodysenteriae vaccine strain. In the seeder vaccination trial nearly all immunised animals developed swine dysentery on subsequent challenge with a virulent strain, but the speed of spread of swine dysentery and faecal score were significantly reduced in animals immunised with the weakly haemolytic strain compared to sham-immunised animals. The IgA response of immunised animals upon challenge with a virulent B. hyodysenteriae strain significantly correlated to a later onset of disease. The correlation between local IgA production and protection induced by a weakly haemolytic B. hyodysenteriae strain provides leads for future vaccine development against swine dysentery.

  18. Proteolysis of plasminogen activator inhibitor-1 by Yersinia pestis remodulates the host environment to promote virulence.

    PubMed

    Eddy, J L; Schroeder, J A; Zimbler, D L; Caulfield, A J; Lathem, W W

    2016-09-01

    Essentials Effect of plasminogen activator inhibitor (PAI)-1 on plague and its Y. pestis cleavage is unknown. An intranasal mouse model of infection was used to determine the role of PAI-1 in pneumonic plague. PAI-1 is cleaved and inactivated by the Pla protease of Y. pestis in the lung airspace. PAI-1 impacts both bacterial outgrowth and the immune response to respiratory Y. pestis infection. Click to hear Dr Bock discuss pathogen activators of plasminogen. Background The hemostatic regulator plasminogen activator inhibitor-1 (PAI-1) inactivates endogenous plasminogen activators and aids in the immune response to bacterial infection. Yersinia pestis, the causative agent of plague, produces the Pla protease, a virulence factor that is required during plague. However, the specific hemostatic proteins cleaved by Pla in vivo that contribute to pathogenesis have not yet been fully elucidated. Objectives To determine whether PAI-1 is cleaved by the Pla protease during pneumonic plague, and to define the impact of PAI-1 on Y. pestis respiratory infection in the presence or absence of Pla. Methods An intranasal mouse model of pneumonic plague was used to assess the levels of total and active PAI-1 in the lung airspace, and the impact of PAI-1 deficiency on bacterial pathogenesis, the host immune response and plasmin generation following infection with wild-type or ∆pla Y. pestis. Results We found that Y. pestis cleaves and inactivates PAI-1 in the lungs in a Pla-dependent manner. The loss of PAI-1 enhances Y. pestis outgrowth in the absence of Pla, and is associated with increased conversion of plasminogen to plasmin. Furthermore, we found that PAI-1 regulates immune cell recruitment, cytokine production and tissue permeability during pneumonic plague. Conclusions Our data demonstrate that PAI-1 is an in vivo target of the Pla protease in the lungs, and that PAI-1 is a key regulator of the pulmonary innate immune response. We conclude that the inactivation of PAI-1 by Y

  19. Cathepsins limit macrophage necroptosis through cleavage of Rip1 kinase.

    PubMed

    McComb, Scott; Shutinoski, Bojan; Thurston, Susan; Cessford, Erin; Kumar, Kriti; Sad, Subash

    2014-06-15

    It has recently been shown that programmed necrosis, necroptosis, may play a key role in the development of inflammation. Deciphering the regulation of this pathway within immune cells may therefore have implications in pathology associated with inflammatory diseases. We show that treatment of macrophages with the pan caspase inhibitor (zVAD-FMK) results in both increased phosphorylation and decreased cleavage of receptor interacting protein kinase-1 (Rip1), leading to necroptosis that is dependent on autocrine TNF signaling. Stimulation of cells with TLR agonists such as LPS in the presence of zVAD-FMK also induced Rip1-phosphorylation via a TNFR-independent mechanism. Further examination of Rip1 expression under these stimulatory conditions revealed a regulatory cleavage of Rip1 in macrophages that is not apparently attributable to caspase-8. Instead, we provide novel evidence that cysteine family cathepsins, which are highly abundant in myeloid cells, can also cleave Rip1 kinase. Using small interfering RNA knockdown, specific cathepsin inhibitors, and cell-free cleavage assays, we demonstrate that cysteine cathepsins B and S can directly cleave Rip1. Finally, we demonstrate that only through combined inhibition of cathepsins and caspase-8 could a potent induction of macrophage necroptosis be achieved. These data reveal a novel mechanism of regulation of necroptosis by cathepsins within macrophage cells. Copyright © 2014 by The American Association of Immunologists, Inc.

  20. Purification and Characterisation of Immunoglobulins from the Australian Black Flying Fox (Pteropus alecto) Using Anti-Fab Affinity Chromatography Reveals the Low Abundance of IgA

    PubMed Central

    Shiell, Brian J.; Beddome, Gary; Cowled, Christopher; Peck, Grantley R.; Huang, Jing; Grimley, Samantha L.; Baker, Michelle L.; Michalski, Wojtek P.

    2013-01-01

    There is now an overwhelming body of evidence that implicates bats in the dissemination of a long list of emerging and re-emerging viral agents, often causing illnesses or death in both animals and humans. Despite this, there is a paucity of information regarding the immunological mechanisms by which bats coexist with highly pathogenic viruses. Immunoglobulins are major components of the adaptive immune system. Early studies found bats may have quantitatively lower antibody responses to model antigens compared to conventional laboratory animals. To further understand the antibody response of bats, the present study purified and characterised the major immunoglobulin classes from healthy black flying foxes, Pteropus alecto. We employed a novel strategy, where IgG was initially purified and used to generate anti-Fab specific antibodies. Immobilised anti-Fab specific antibodies were then used to capture other immunoglobulins from IgG depleted serum. While high quantities of IgM were successfully isolated from serum, IgA was not. Only trace quantities of IgA were detected in the serum by mass spectrometry. Immobilised ligands specific to IgA (Jacalin, Peptide M and staphylococcal superantigen-like protein) also failed to capture P. alecto IgA from serum. IgM was the second most abundant serum antibody after IgG. A survey of mucosal secretions found IgG was the dominant antibody class rather than IgA. Our study demonstrates healthy P. alecto bats have markedly less serum IgA than expected. Higher quantities of IgG in mucosal secretions may be compensation for this low abundance or lack of IgA. Knowledge and reagents developed within this study can be used in the future to examine class-specific antibody response within this important viral host. PMID:23308125

  1. Purification and characterisation of immunoglobulins from the Australian black flying fox (Pteropus alecto) using anti-fab affinity chromatography reveals the low abundance of IgA.

    PubMed

    Wynne, James W; Di Rubbo, Antonio; Shiell, Brian J; Beddome, Gary; Cowled, Christopher; Peck, Grantley R; Huang, Jing; Grimley, Samantha L; Baker, Michelle L; Michalski, Wojtek P

    2013-01-01

    There is now an overwhelming body of evidence that implicates bats in the dissemination of a long list of emerging and re-emerging viral agents, often causing illnesses or death in both animals and humans. Despite this, there is a paucity of information regarding the immunological mechanisms by which bats coexist with highly pathogenic viruses. Immunoglobulins are major components of the adaptive immune system. Early studies found bats may have quantitatively lower antibody responses to model antigens compared to conventional laboratory animals. To further understand the antibody response of bats, the present study purified and characterised the major immunoglobulin classes from healthy black flying foxes, Pteropus alecto. We employed a novel strategy, where IgG was initially purified and used to generate anti-Fab specific antibodies. Immobilised anti-Fab specific antibodies were then used to capture other immunoglobulins from IgG depleted serum. While high quantities of IgM were successfully isolated from serum, IgA was not. Only trace quantities of IgA were detected in the serum by mass spectrometry. Immobilised ligands specific to IgA (Jacalin, Peptide M and staphylococcal superantigen-like protein) also failed to capture P. alecto IgA from serum. IgM was the second most abundant serum antibody after IgG. A survey of mucosal secretions found IgG was the dominant antibody class rather than IgA. Our study demonstrates healthy P. alecto bats have markedly less serum IgA than expected. Higher quantities of IgG in mucosal secretions may be compensation for this low abundance or lack of IgA. Knowledge and reagents developed within this study can be used in the future to examine class-specific antibody response within this important viral host.

  2. The Escherichia coli Subtilase Cytotoxin A Subunit Specifically Cleaves Cell-surface GRP78 Protein and Abolishes COOH-terminal-dependent Signaling

    PubMed Central

    Ray, Rupa; de Ridder, Gustaaf G.; Eu, Jerry P.; Paton, Adrienne W.; Paton, James C.; Pizzo, Salvatore V.

    2012-01-01

    GRP78, a molecular chaperone with critical endoplasmic reticulum functions, is aberrantly expressed on the surface of cancer cells, including prostate and melanoma. Here it functions as a pro-proliferative and anti-apoptotic signaling receptor via NH2-terminal domain ligation. Auto-antibodies to this domain may appear in cancer patient serum where they are a poor prognostic indicator. Conversely, GRP78 COOH-terminal domain ligation is pro-apoptotic and anti-proliferative. There is no method to disrupt cell-surface GRP78 without compromising the total GRP78 pool, making it difficult to study cell-surface GRP78 function. We studied six cell lines representing three cancer types. One cell line per group expresses high levels of cell-surface GRP78, and the other expresses low levels (human hepatoma: Hep3B and HepG2; human prostate cancer: PC3 and 1-LN; murine melanoma: B16F0 and B16F1). We investigated the effect of Escherichia coli subtilase cytoxin catalytic subunit (SubA) on GRP78. We report that SubA specifically cleaves cell-surface GRP78 on HepG2, 1-LN, and B16F1 cells without affecting intracellular GRP78. B16F0 cells (GRP78low) have lower amounts of cleaved cell-surface GRP78. SubA has no effect on Hep3B and PC3 cells. The predicted 28-kDa GRP78 COOH-terminal fragment is released into the culture medium by SubA treatment, and COOH-terminal domain signal transduction is abrogated, whereas pro-proliferative signaling mediated through NH2-terminal domain ligation is unaffected. These experiments clarify cell-surface GRP78 topology and demonstrate that the COOH-terminal domain is necessary for pro-apoptotic signal transduction occurring upon COOH-terminal antibody ligation. SubA is a powerful tool to specifically probe the functions of cell-surface GRP78. PMID:22851173

  3. The Escherichia coli subtilase cytotoxin A subunit specifically cleaves cell-surface GRP78 protein and abolishes COOH-terminal-dependent signaling.

    PubMed

    Ray, Rupa; de Ridder, Gustaaf G; Eu, Jerry P; Paton, Adrienne W; Paton, James C; Pizzo, Salvatore V

    2012-09-21

    GRP78, a molecular chaperone with critical endoplasmic reticulum functions, is aberrantly expressed on the surface of cancer cells, including prostate and melanoma. Here it functions as a pro-proliferative and anti-apoptotic signaling receptor via NH(2)-terminal domain ligation. Auto-antibodies to this domain may appear in cancer patient serum where they are a poor prognostic indicator. Conversely, GRP78 COOH-terminal domain ligation is pro-apoptotic and anti-proliferative. There is no method to disrupt cell-surface GRP78 without compromising the total GRP78 pool, making it difficult to study cell-surface GRP78 function. We studied six cell lines representing three cancer types. One cell line per group expresses high levels of cell-surface GRP78, and the other expresses low levels (human hepatoma: Hep3B and HepG2; human prostate cancer: PC3 and 1-LN; murine melanoma: B16F0 and B16F1). We investigated the effect of Escherichia coli subtilase cytoxin catalytic subunit (SubA) on GRP78. We report that SubA specifically cleaves cell-surface GRP78 on HepG2, 1-LN, and B16F1 cells without affecting intracellular GRP78. B16F0 cells (GRP78(low)) have lower amounts of cleaved cell-surface GRP78. SubA has no effect on Hep3B and PC3 cells. The predicted 28-kDa GRP78 COOH-terminal fragment is released into the culture medium by SubA treatment, and COOH-terminal domain signal transduction is abrogated, whereas pro-proliferative signaling mediated through NH(2)-terminal domain ligation is unaffected. These experiments clarify cell-surface GRP78 topology and demonstrate that the COOH-terminal domain is necessary for pro-apoptotic signal transduction occurring upon COOH-terminal antibody ligation. SubA is a powerful tool to specifically probe the functions of cell-surface GRP78.

  4. DPP8/9 inhibition induces pro-caspase-1-dependent monocyte and macrophage pyroptosis

    PubMed Central

    Okondo, Marian C.; Johnson, Darren C.; Sridharan, Ramya; Go, Eun Bin; Chui, Ashley J.; Wang, Mitchell S.; Poplawski, Sarah E.; Wu, Wengen; Liu, Yuxin; Lai, Jack H.; Sanford, David G.; Arciprete, Michael O.; Golub, Todd R.; Bachovchin, William W.; Bachovchin, Daniel A.

    2017-01-01

    Val-boroPro (talabostat, PT-100), a nonselective inhibitor of post-proline cleaving serine proteases, stimulates mammalian immune systems through an unknown mechanism of action. Despite this lack of mechanistic understanding, Val-boroPro has attracted significant interest as a potential anticancer agent, reaching Phase III trials in humans. Here we show that Val-boroPro stimulates the immune system by triggering a proinflammatory form of cell death in monocytes and macrophages known as pyroptosis. We demonstrate that the inhibition of two serine proteases, DPP8 and DPP9, activates the proprotein form of caspase-1 independent of the inflammasome adaptor ASC. Activated pro-caspase-1 does not efficiently process itself or IL-1β, but does cleave and activate gasdermin D to induce pyroptosis. Mice lacking caspase-1 do not show immune stimulation after treatment with Val-boroPro. Our data identifies the first small molecule that induces pyroptosis and reveals a new checkpoint that controls the activation of the innate immune system. PMID:27820798

  5. Use of eculizumab in crescentic IgA nephropathy: proof of principle and conundrum?

    PubMed Central

    Ring, Troels; Pedersen, Birgitte Bang; Salkus, Giedrius; Goodship, Timothy H.J.

    2015-01-01

    IgA nephropathy (IgAN) is characterized by a variable clinical course and multifaceted pathophysiology. There is substantial evidence to suggest that complement activation plays a pivotal role in the pathogenesis of the disease. Therefore, complement inhibition using the humanized anti-C5 monoclonal antibody eculizumab could be a rational treatment. We report here a 16-year-old male with the vasculitic form of IgAN who failed to respond to aggressive conventional therapy including high-dose steroids, cyclophosphamide and plasma exchange and who was treated with four weekly doses of 900 mg eculizumab followed by a single dose of 1200 mg. He responded rapidly to this treatment and has had a stable creatinine around 150 µmol/L (1.67 mg/dL) for >6 months. However, proteinuria was unabated on maximal conventional anti-proteinuric treatment, and a repeat renal biopsy 11 months after presentation revealed severe chronic changes. We believe this case provides proof of principle that complement inhibition may be beneficial in IgAN but also that development of chronicity may be independent of complement. PMID:26413271

  6. A mucosally targeted subunit vaccine candidate eliciting HIV-1 transcytosis-blocking Abs

    PubMed Central

    Matoba, Nobuyuki; Magérus, Aude; Geyer, Brian C.; Zhang, Yunfang; Muralidharan, Mrinalini; Alfsen, Annette; Arntzen, Charles J.; Bomsel, Morgane; Mor, Tsafrir S.

    2004-01-01

    A vaccine that would engage the mucosal immune system against a broad range of HIV-1 subtypes and prevent epithelial transmission is highly desirable. Here we report fusing the mucosal targeting B subunit of cholera toxin to the conserved galactosylceramide-binding domain (including the ELDKWA-neutralizing epitope) of the HIV-1 gp41 envelope protein, which mediates the transcytosis of HIV-1 across the mucosal epithelia. Chimeric protein expressed in bacteria or plants assembled into oligomers that were capable of binding galactosyl-ceramide and GM1 gangliosides. Mucosal (intranasal) administration in mice of the purified chimeric protein followed by an i.p. boost resulted in transcytosis-neutralizing serum IgG and mucosal IgA responses and induced immunological memory. Plant production of mucosally targeted immunogens could be particularly useful for immunization programs in developing countries, where desirable product traits include low cost of manufacture, heat stability, and needle-free delivery. PMID:15347807

  7. Hydrolysed fumonisin B1 and N-(deoxy-D-fructos-1-yl)-fumonisin B1: stability and catabolic fate under simulated human gastrointestinal conditions.

    PubMed

    Cirlini, Martina; Hahn, Irene; Varga, Elisabeth; Dall'Asta, Margherita; Falavigna, Claudia; Calani, Luca; Berthiller, Franz; Del Rio, Daniele; Dall'Asta, Chiara

    2015-02-01

    Food processing may induce thermal degradation of fumonisins in corn via Maillard-type reactions, or alkaline hydrolysis via loss of the two tricarballylic acid moieties. In the former case, N-(1-deoxy-D-fructos-1-yl)-fumonisin B(1) (NDF) can be formed, while the latter derivative is called hydrolysed fumonisin B(1) (HFB(1)). The aim of this study was to deepen the knowledge about the gastrointestinal stability of HFB(1) and NDF in humans. Due to the lack of standard, NDF was chemically synthesised and cleaned up in high purity to be used for further experiments. While NDF is already partially cleaved (about 41%) during simulated digestion, it remained rather stable towards human colon microflora. In contrast to this, HFB(1) is partially metabolised by the colon microflora to unknown compounds after 24 h of fermentation, as seen by a loss of about 22%. Concluding, the cleavage of NDF during digestion as well as the likely metabolisation of HFB(1) emphasise the need for animal trials to ascertain their toxicity in vivo.

  8. Distinct patterns of IgG and IgA against food and microbial antigens in serum and feces of patients with inflammatory bowel diseases.

    PubMed

    Frehn, Lisa; Jansen, Anke; Bennek, Eveline; Mandic, Ana D; Temizel, Ilknur; Tischendorf, Stefanie; Verdier, Julien; Tacke, Frank; Streetz, Konrad; Trautwein, Christian; Sellge, Gernot

    2014-01-01

    Inflammatory bowel disease (IBD) is associated with a defective intestinal barrier and enhanced adaptive immune responses against commensal microbiota. Immune responses against food antigens in IBD patients remain poorly defined. IgG and IgA specific for food and microfloral antigens (wheat and milk extracts; purified ovalbumin; Escherichia coli and Bacteroides fragilis lysates; mannan from Saccharomyces cerevisiae) were analyzed by ELISA in the serum and feces of patients with Crohn's disease (CD; n = 52 for serum and n = 20 for feces), ulcerative colitis (UC; n = 29; n = 17), acute gastroenteritis/colitis (AGE; n = 12; n = 9) as well as non-inflammatory controls (n = 61; n = 39). Serum anti-Saccharomyces cerevisiae antibodies (ASCA) and anti-B. fragilis IgG and IgA levels were increased in CD patients whereas antibody (Ab) levels against E. coli and food antigens were not significantly different within the patient groups and controls. Subgroup analysis revealed that CD patients with severe diseases defined by stricturing and penetrating lesions have slightly higher anti-food and anti-microbial IgA levels whereas CD and UC patients with arthropathy have decreased anti-food IgG levels. Treatment with anti-TNF-α Abs in CD patients was associated with significantly decreased ASCA IgG and IgA and anti-E. coli IgG. In the feces specific IgG levels against all antigens were higher in CD and AGE patients while specific IgA levels were higher in non-IBD patients. Anti-food IgG and IgA levels did not correlate with food intolerance. In contrast to anti-microbial Abs, we found only minor changes in serum anti-food Ab levels in specific subgroups of IBD patients. Fecal Ab levels towards microbial and food antigens show distinct patterns in controls, CD and UC patients.

  9. Total serum IgE and parasite-specific IgG and IgA antibodies in human strongyloidiasis.

    PubMed

    Rossi, C L; Takahashi, E E; Partel, C D; Teodoro, L G; da Silva, L J

    1993-01-01

    Total serum IgE, and Strongyloides-specific IgG and IgA antibodies were studied in 27 patients with parasitologically proven strongyloidiasis. Clinical manifestations in this case series were investigated by a retrospective study of the patient's records. Total serum IgE levels were elevated (greater than 250 IU/ml) in 59% of the patients (mean concentration = 1364 IU/ml). Parasite-specific IgG and IgA antibodies were detected by ELISA in the serum of 23 (85.2%) and 21 (77.8%) patients, respectively. Elevated serum IgE and clinical manifestations were not useful indexes of the presence of strongyloidiasis. On the other hand, our results support the view that serologic tests, particularly ELISA for detecting Strongyloides-specific IgG antibodies, can be usefully exploited for diagnostic purposes in strongyloidiasis.

  10. Characterization of PgPepO, a bacterial homologue of endothelin-converting enzyme-1.

    PubMed

    Carson, Julie A; Ansai, Toshihiro; Awano, Shuji; Yu, Weixian; Takehara, Tadamichi; Turner, Anthony J

    2002-08-01

    PgPepO is a homologue of endothelin-converting enzyme-1 (ECE-1), with which it shares 31% identity. PgPepO was isolated from the periodontal pathogen Porphyromonas gingivalis. Recent studies have suggested a link between periodontal and cardiovascular disease, and several groups have suggested that bacterial and viral infections may contribute to the latter. P. gingivalis possesses the ability to invade, and multiply within, aortic endothelial cells and has been localized to atherosclerotic plaques. PgPepO was expressed and purified to homogeneity and we have begun detailed functional analysis, in terms of substrate preference and inhibitor specificity, in order to provide active-site comparisons with other members of the neprilysin (NEP)/ECE family. PgPepO possesses similar substrate specificity to ECE-1 and has been shown to cleave big endothelin-1 (big ET-1), big ET-2 and big ET-3, converting the substrates into their respective mature endothelin peptides. Substance P, angiotensin I, angiotensin II and neurotensin are all cleaved at multiple sites by PgPepO and the kinetics of these reactions have been compared. The potent vasoconstrictor urotensin II is not hydrolysed by PgPepO. Cleavage of bradykinin by PgPepO occurs at the Pro(7)-Phe(8) bond and is inhibited by the NEP and ECE-1 inhibitor phosphoramidon in a pH-dependent fashion (IC(50) =10 microM at pH 7.0) but not by thiorphan, an NEP-specific inhibitor. PgPepO activity is completely inhibited by EDTA. Characterization of this enzyme is important in elucidating possible links between periodontal pathogens and cardiovascular disorders such as atherosclerosis, and provides an opportunity to gain structural information on a bacterial protein with striking similarity to human ECE-1.

  11. Type 1 Does The Two-Step: Type 1 Secretion Substrates With A Functional Periplasmic Intermediate.

    PubMed

    Smith, Timothy J; Sondermann, Holger; O'Toole, George A

    2018-06-04

    Bacteria have evolved several secretion strategies for polling and responding to environmental flux and insult. Of these, the type 1 secretion system (T1SS) is known to secrete an array of biologically diverse proteins - from small < 10 kDa bacteriocins to gigantic adhesins with a mass over 1 MDa. For the last several decades T1SS have been characterized as a one-step translocation strategy whereby the secreted substrate is transported directly into the extracellular environment from the cytoplasm with no periplasmic intermediate. Recent phylogenetic, biochemical, and genetic evidence point to a distinct sub-group of T1SS machinery linked with a bacterial transglutaminase-like cysteine proteinase (BTLCP), which uses a two-step secretion mechanism. BTLCP-linked T1SS transport a class of repeats-in-toxin (RTX) adhesins that are critical for biofilm formation. The prototype of this RTX adhesin group, LapA of Pseudomonas fluorescens Pf0-1, uses a novel N-terminal retention module to anchor the adhesin at the cell surface as a secretion intermediate threaded through the outer membrane-localized, TolC-like protein LapE. This secretion intermediate is post-translationally cleaved by the BTLCP family LapG protein to release LapA from its cognate T1SS pore. Thus, secretion of LapA and related RTX adhesins into the extracellular environment appears to be a T1SS-mediated, two-step process that involves a periplasmic intermediate. In this review, we contrast the T1SS machinery and substrates of the BLTCP-linked two-step secretion process with those of the classical one-step T1SS to better understand the newly recognized and expanded role of this secretion machinery. Copyright © 2018 American Society for Microbiology.

  12. An Efficient Lanthanide-Dependent DNAzyme Cleaving 2'-5'-Linked RNA.

    PubMed

    Zhou, Wenhu; Ding, Jinsong; Liu, Juewen

    2016-05-17

    RNA can form two types of linkage. In addition to the predominant 3'-5' linkage, 2'-5'-linked RNA is also important in biology, medicine, and prebiotic studies. Here, in vitro selection was used to isolate a DNAzyme that specifically cleaves 2'-5' RNA by using Ce(3+) as the metal cofactor, but leaves the 3'-5' counterpart intact. This Ce5 DNAzyme requires trivalent light lanthanide ions and shows a rate of 0.16 min(-1) in the presence of 10 μm Ce(3+) ; the activity decreases with heavier lanthanide ions. This is the fastest DNAzyme reported for this reaction, and it might enable applications in chemical biology. As a proof-of-concept, using this DNAzyme, the reactions between phosphorothioate-modified RNA and strongly thiophilic metals (Hg(2+) and Tl(3+) ) were studied as a function of pH. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Activation and cleavage of SASH1 by caspase-3 mediates an apoptotic response.

    PubMed

    Burgess, Joshua T; Bolderson, Emma; Adams, Mark N; Baird, Anne-Marie; Zhang, Shu-Dong; Gately, Kathy A; Umezawa, Kazuo; O'Byrne, Kenneth J; Richard, Derek J

    2016-11-10

    Apoptosis is a highly regulated cellular process that functions to remove undesired cells from multicellular organisms. This pathway is often disrupted in cancer, providing tumours with a mechanism to avoid cell death and promote growth and survival. The putative tumour suppressor, SASH1 (SAM and SH3 domain containing protein 1), has been previously implicated in the regulation of apoptosis; however, the molecular role of SASH1 in this process is still unclear. In this study, we demonstrate that SASH1 is cleaved by caspase-3 following UVC-induced apoptosis. Proteolysis of SASH1 enables the C-terminal fragment to translocate from the cytoplasm to the nucleus where it associates with chromatin. The overexpression of wild-type SASH1 or a cleaved form of SASH1 representing amino acids 231-1247 leads to an increase in apoptosis. Conversely, mutation of the SASH1 cleavage site inhibits nuclear translocation and prevents the initiation of apoptosis. SASH1 cleavage is also required for the efficient translocation of the transcription factor nuclear factor-κB (NF-κB) to the nucleus. The use of the NF-κB inhibitor DHMEQ demonstrated that the effect of SASH1 on apoptosis was dependent on NF-κB, indicating a codependence between SASH1 and NF-κB for this process.

  14. Methylation of PLCD1 and adenovirus-mediated PLCD1 overexpression elicits a gene therapy effect on human breast cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mu, Haixi; Department of Endocrine and breast Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016; Wang, Na

    Our previous study showed that PLCD1 significantly decreases cell proliferation and affects cell cycle progression in breast cancer cells. In the present study, we aimed to investigate its functional and molecular mechanisms, and whether or not can become a new target for gene therapies. We found reduced PLCD1 protein expression in breast tumor tissues compared with paired surgical margin tissues. PLCD1 promoter CpG methylation was detected in 55 of 96 (57%) primary breast tumors, but not in surgical-margin tissues and normal breast tissues. Ectopic expression of PLCD1 inhibited breast tumor cell proliferation in vivo by inducing apoptosis and suppressed tumormore » cell migration by regulating cytoskeletal reorganization proteins including RhoA and phospho-cofilin. Furthermore, we found that PLCD1 induced p53 accumulation, increased p27 and p21 protein levels, and cleaved PARP. Finally, we constructed an adenoviral vector expressing PLCD1 (AdH5-PLCD1), which exhibited strong cytotoxicity in breast cancer cells. Our findings provide insights into the development of PLCD1 gene therapies for breast cancer and perhaps, other human cancers. - Highlights: • PLCD1 is downregulated via hypermethylation in breast cancer. • PLCD1 suppressed cell migration by regulating cytoskeletal reorganization proteins. • Adenovirus AdHu5-PLCD1 may be a novel therapeutic option for breast cancer.« less

  15. Extracapillary proliferation in IgA nephropathy; recent findings and new ideas.

    PubMed

    Nasri, Hamid; Mubarak, Muhammed

    2015-01-01

    IgA nephropathy (IgAN) is an autoimmune disorder and is the most common form of primary glomerulonephritis (GN) worldwide. Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO) and Web of Science have been searched. It is a slowly progressing disorder that leads to end-stage renal disease (ESRD) in up to 50% of the patients within 25 years of the onset of the disease. IgAN is defined by predominant IgA deposition in the mesangial area on immunofluorescence (IF) microscopy. Its histology varies from mild focal segmental proliferation of mesangial cells to severe diffuse global proliferation with extracapillary proliferation (crescent formation). The Oxford classification, designed in 2009, is a new classification for the evaluation of morphologic lesions of IgAN. This classification, containing four pathology variables, was found to have prognostic implications. The variables included are mesangial hypercellularity (M), endocapillary proliferation (E), segmental glomerulosclerosis (S) and the proportion of interstitial fibrosis and tubular atrophy (T). However, crescents were not included in the Oxford classification. In this mini-review, we describe the recent publications about the significance of extracapillary proliferation in IgAN and we conclude that, there is much controversy about the role of extracapillary proliferation as a significant prognostic factor in IgAN. Hence, it is important to re-consider crescents in IgAN patients. Therefore, we suggest further investigations on this aspect of IgAN disease.

  16. Extracapillary proliferation in IgA nephropathy; recent findings and new ideas

    PubMed Central

    Nasri, Hamid; Mubarak, Muhammed

    2015-01-01

    Context: IgA nephropathy (IgAN) is an autoimmune disorder and is the most common form of primary glomerulonephritis (GN) worldwide. Evidence Acquisitions: Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO) and Web of Science have been searched. Results: It is a slowly progressing disorder that leads to end-stage renal disease (ESRD) in up to 50% of the patients within 25 years of the onset of the disease. IgAN is defined by predominant IgA deposition in the mesangial area on immunofluorescence (IF) microscopy. Its histology varies from mild focal segmental proliferation of mesangial cells to severe diffuse global proliferation with extracapillary proliferation (crescent formation). The Oxford classification, designed in 2009, is a new classification for the evaluation of morphologic lesions of IgAN. This classification, containing four pathology variables, was found to have prognostic implications. The variables included are mesangial hypercellularity (M), endocapillary proliferation (E), segmental glomerulosclerosis (S) and the proportion of interstitial fibrosis and tubular atrophy (T). However, crescents were not included in the Oxford classification. Conclusions: In this mini-review, we describe the recent publications about the significance of extracapillary proliferation in IgAN and we conclude that, there is much controversy about the role of extracapillary proliferation as a significant prognostic factor in IgAN. Hence, it is important to re-consider crescents in IgAN patients. Therefore, we suggest further investigations on this aspect of IgAN disease. PMID:25657978

  17. Establishment and characterization of a novel head and neck squamous cell carcinoma cell line USC-HN1.

    PubMed

    Liebertz, Daniel J; Lechner, Melissa G; Masood, Rizwan; Sinha, Uttam K; Han, Jing; Puri, Raj K; Correa, Adrian J; Epstein, Alan L

    2010-02-22

    Head and neck squamous cell carcinoma (HNSCC) is an aggressive and lethal malignancy. Publically available cell lines are mostly of lingual origin, or have not been carefully characterized. Detailed characterization of novel HNSCC cell lines is needed in order to provide researchers a concrete keystone on which to build their investigations. The USC-HN1 cell line was established from a primary maxillary HNSCC biopsy explant in tissue culture. The immortalized cells were then further characterized by heterotransplantation in Nude mice; immunohistochemical staining for relevant HNSCC biomarkers; flow cytometry for surface markers; cytogenetic karyotypic analysis; human papillomavirus and Epstein-Barr virus screening; qRT-PCR for oncogene and cytokine analysis; investigation of activated, cleaved Notch1 levels; and detailed 35,000 gene microarray analysis. Characterization experiments confirmed the human HNSCC origin of USC-HN1, including a phenotype similar to the original tumor. Viral screening revealed no HPV or EBV infection, while western blotting displayed significant upregulation of activated, cleaved Notch1. USC-HN1, a novel immortalized cell line has been derived from a maxillary HNSCC. Characterization studies have shown that the cell line is of HNSCC origin and displays many of the same markers previously reported in the literature. USC-HN1 is available for public research and will further the investigation of HNSCC and the development of new therapeutic modalities.

  18. Adaptor protein 2–mediated endocytosis of the β-secretase BACE1 is dispensable for amyloid precursor protein processing

    PubMed Central

    Prabhu, Yogikala; Burgos, Patricia V.; Schindler, Christina; Farías, Ginny G.; Magadár, Javier G.; Bonifacino, Juan S.

    2012-01-01

    The β-site amyloid precursor protein (APP)–cleaving enzyme 1 (BACE1) is a transmembrane aspartyl protease that catalyzes the proteolytic processing of APP and other plasma membrane protein precursors. BACE1 cycles between the trans-Golgi network (TGN), the plasma membrane, and endosomes by virtue of signals contained within its cytosolic C-terminal domain. One of these signals is the DXXLL-motif sequence DISLL, which controls transport between the TGN and endosomes via interaction with GGA proteins. Here we show that the DISLL sequence is embedded within a longer [DE]XXXL[LI]-motif sequence, DDISLL, which mediates internalization from the plasma membrane by interaction with the clathrin-associated, heterotetrameric adaptor protein 2 (AP-2) complex. Mutation of this signal or knockdown of either AP-2 or clathrin decreases endosomal localization and increases plasma membrane localization of BACE1. Remarkably, internalization-defective BACE1 is able to cleave an APP mutant that itself cannot be delivered to endosomes. The drug brefeldin A reversibly prevents BACE1-catalyzed APP cleavage, ruling out that this reaction occurs in the endoplasmic reticulum (ER) or ER–Golgi intermediate compartment. Taken together, these observations support the notion that BACE1 is capable of cleaving APP in late compartments of the secretory pathway. PMID:22553349

  19. Cleavage of the urokinase receptor (uPAR) on oral cancer cells: regulation by transforming growth factor - β1 (TGF-β1) and potential effects on migration and invasion.

    PubMed

    Magnussen, Synnove Norvoll; Hadler-Olsen, Elin; Costea, Daniela Elena; Berg, Eli; Jacobsen, Cristiane Cavalcanti; Mortensen, Bente; Salo, Tuula; Martinez-Zubiaurre, Inigo; Winberg, Jan-Olof; Uhlin-Hansen, Lars; Svineng, Gunbjorg

    2017-05-19

    Urokinase plasminogen activator (uPA) receptor (uPAR) is up-regulated at the invasive tumour front of human oral squamous cell carcinoma (OSCC), indicating a role for uPAR in tumour progression. We previously observed elevated expression of uPAR at the tumour-stroma interface in a mouse model for OSCC, which was associated with increased proteolytic activity. The tumour microenvironment regulated uPAR expression, as well as its glycosylation and cleavage. Both full-length- and cleaved uPAR (uPAR (II-III)) are involved in highly regulated processes such as cell signalling, proliferation, migration, stem cell mobilization and invasion. The aim of the current study was to analyse tumour associated factors and their effect on uPAR cleavage, and the potential implications for cell proliferation, migration and invasion. Mouse uPAR was stably overexpressed in the mouse OSCC cell line AT84. The ratio of full-length versus cleaved uPAR as analysed by Western blotting and its regulation was assessed by addition of different protease inhibitors and transforming growth factor - β1 (TGF-β1). The role of uPAR cleavage in cell proliferation and migration was analysed using real-time cell analysis and invasion was assessed using the myoma invasion model. We found that when uPAR was overexpressed a proportion of the receptor was cleaved, thus the cells presented both full-length uPAR and uPAR (II-III). Cleavage was mainly performed by serine proteases and urokinase plasminogen activator (uPA) in particular. When the OSCC cells were stimulated with TGF-β1, the production of the uPA inhibitor PAI-1 was increased, resulting in a reduction of uPAR cleavage. By inhibiting cleavage of uPAR, cell migration was reduced, and by inhibiting uPA activity, invasion was reduced. We could also show that medium containing soluble uPAR (suPAR), and cleaved soluble uPAR (suPAR (II-III)), induced migration in OSCC cells with low endogenous levels of uPAR. These results show that soluble factors in

  20. Prognostic impact of serum bilirubin level on long-term renal survival in IgA nephropathy.

    PubMed

    Tanaka, Shigeru; Ninomiya, Toshiharu; Masutani, Kosuke; Nagata, Masaharu; Tsuchimoto, Akihiro; Tsuruya, Kazuhiko; Kitazono, Takanari

    2015-12-01

    Serum bilirubin has been recognized as a novel endogenous antioxidant. The aim of our study was to evaluate the impact of serum bilirubin on kidney prognosis in IgA nephropathy (IgAN). We followed retrospectively 694 patients with IgAN diagnosed by renal biopsy between 1982 and 2010. The risk factors for developing end-stage renal disease (ESRD) were estimated using a Cox proportional hazard model. Predictive performance between models with or without serum bilirubin was evaluated by calculating the net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Seventy-seven patients developed ESRD during the median 4.9 years of follow-up. Estimated glomerular filtration rate, proteinuria and histological severity were inversely related to bilirubin levels. In multivariate analysis, serum bilirubin was an independent risk factor for ESRD (hazard ratio for every 0.1 mg/dL decrease in serum bilirubin, 1.18; 95 % CI, 1.04-1.33). The incidence rate of ESRD decreased linearly with the increases in bilirubin levels (P for trend <0.01). When bilirubin was incorporated into a model with conventional ESRD risk factors, the NRI and IDI were 0.281 (P = 0.02) and 0.019 (P = 0.01), respectively. We demonstrated that lower bilirubin levels were significantly associated with higher risk of ESRD in IgAN. In addition, bilirubin provided incremental predictive value in the risk assessment for progression of IgAN beyond that provided by standard risk factors.

  1. Styrene Polymerization under Ambient Conditions by using a Transient 1,3,2-Diazaphospholane-2-oxyl Complex.

    PubMed

    Heurich, Tobias; Qu, Zheng-Wang; Kunzmann, Robert; Schnakenburg, Gregor; Engeser, Marianne; Nožinović, Senada; Streubel, Rainer

    2018-04-25

    A combined theoretical and experimental study on the formation and reactivity of a P-OTEMP (P-bound TEMPO (TEMPO=2,2,6,6-tetramethyl-piperidin-1-oxyl)) substituted 1,3,2-diazaphospholane W(CO) 5 complex is presented, including DFT-based mechanistic details. The complex possesses a thermally labile O-N bond that cleaves homolytically yielding the transient 1,3,2-diazaphospholane-2-oxyl complex [(CO) 5 W(R 2 PO . )], which acts as a radical initiator for styrene polymerization under ambient conditions. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. PLK1 regulation of PCNT cleavage ensures fidelity of centriole separation during mitotic exit.

    PubMed

    Kim, Jaeyoun; Lee, Kwanwoo; Rhee, Kunsoo

    2015-12-09

    Centrioles are duplicated and segregated in close link to the cell cycle. During mitosis, daughter centrioles are disengaged and eventually separated from mother centrioles. New daughter centrioles may be generated only after centriole separation. Therefore, centriole separation is considered a licensing step for centriole duplication. It was previously known that separase specifically cleaves pericentrin (PCNT) during mitotic exit. Here we report that PCNT has to be phosphorylated by PLK1 to be a suitable substrate of separase. Phospho-resistant mutants of PCNT are not cleaved by separase and eventually inhibit centriole separation. Furthermore, phospho-mimetic PCNT mutants rescue centriole separation even in the presence of a PLK1 inhibitor. On the basis on these results, we propose that PLK1 phosphorylation is a priming step for separase-mediated cleavage of PCNT and eventually for centriole separation. PLK1 phosphorylation of PCNT provides an additional layer of regulatory mechanism to ensure the fidelity of centriole separation during mitotic exit.

  3. The Akt/mTOR/p70S6K pathway is activated in IgA nephropathy and rapamycin may represent a viable treatment option.

    PubMed

    Tian, Jihua; Wang, Yanhong; Guo, Haixiu; Li, Rongshan

    2015-12-01

    IgA nephropathy (IgAN) is one of the most frequent forms of glomerulonephritis, and 20 to 40% of patients progress to end-stage renal disease (ESRD) within 20 years of disease onset. However, little is known about the molecular pathways involved in the altered physiology of mesangial cells during IgAN progression. This study was designed to explore the role of mTOR signaling and the potential of targeted rapamycin therapy in a rat model of IgAN. After establishing an IgA nephropathy model, the rats were randomly divided into four groups: control, control+rapamycin, IgAN and IgA+rapamycin. Western blotting and immunohistochemistry were performed to determine phospho-Akt, p70S6K and S6 protein levels. Coomassie Brilliant Blue was utilized to measure 24-h urinary protein levels. The biochemical parameters of the rats were analyzed with an autoanalyzer. To evaluate IgA deposition in the glomeruli, FITC-conjugated goat anti-rat IgA antibody was used for direct immunofluorescence. Cellular proliferation and the mesangial matrix in glomeruli were assayed via histological and morphometric procedures. Our results showed that p70S6K, S6 and Akt phosphorylation were significantly upregulated in IgAN rats, and rapamycin effectively inhibited p70S6K and S6 phosphorylation. A low dose of the mTOR inhibitor rapamycin reduced proteinuria, inhibited IgA deposition, and protected kidney function in an IgAN rat model. Low-dose rapamycin treatment corresponded to significantly lower cellular proliferation rates and a decreased mesangial matrix in the glomeruli. In conclusion, the Akt/mTOR/p70S6K pathway was activated in IgAN, and our findings suggested that rapamycin may represent a viable option for the treatment of IgAN. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Intranasal coadministration of Cholera toxin with amoeba lysates modulates the secretion of IgA and IgG antibodies, production of cytokines and expression of pIgR in the nasal cavity of mice in the model of Naegleria fowleri meningoencephalitis.

    PubMed

    Carrasco-Yepez, Maricela; Campos-Rodriguez, Rafael; Lopez-Reyes, Israel; Bonilla-Lemus, Patricia; Rodriguez-Cortes, Antonio Yahve; Contis-Montes de Oca, Arturo; Jarillo-Luna, Adriana; Miliar-Garcia, Angel; Rojas-Hernandez, Saul

    2014-11-01

    The nasal mucosa is the first contact with antigens to induce IgA response. The role of this site has rarely been studied. We have shown than intranasal administration with Naegleria fowleri lysates plus Cholera toxin (CT) increased the protection (survival up to 100%) against N. fowleri infection in mice and apparently antibodies IgA and IgG together with polymorphonuclear (PMN) cells avoid the attachment of N. fowleri to apical side of the nasal epithelium. We also observed that nasal immunization resulted in the induction of antigen-specific IgG subclasses (IgG1 and IgG2a) in nasal washes at days 3 and 9 after the challenge and IgA and IgG in the nasal cavity, compared to healthy and infected mice. We found that immunization with both treatments, N. fowleri lysates plus CT or CT alone, increased the expression of the genes for alpha chain, its receptor (pIgR), and it also increased the expression of the corresponding proteins evidenced by the ∼65 and ∼74kDa bands, respectively. Since the production of pIgR, IgA and IgG antibodies, is up-regulated by some factors, we analyzed the expression of genes for IL-10, IL-6, IFN-γ, TNF-α and IL-1β by using RT-PCR of nasal passages. Immunization resulted in an increased expression of IL-10, IL-6, and IFN-γ cytokines. We also aimed to examine the possible influences of immunization and challenge on the production of inflammatory cytokines (TNF-α and IL-1β). We observed that the stimulus of immunization inhibits the production of TNF-α compared to the infected group where the infection without immunization causes an increase in it. Thus, it is possible that the coexistence of selected cytokines produced by our immunization model may provide a highly effective immunological environment for the production of IgA, IgG and pIgR as well as a strong activation of the PMN in mucosal effector tissue such as nasal passages. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Meprin A impairs epithelial barrier function, enhances monocyte migration, and cleaves the tight junction protein occludin

    PubMed Central

    Bao, Jialing; Yura, Renee E.; Matters, Gail L.; Bradley, S. Gaylen; Shi, Pan; Tian, Fang

    2013-01-01

    Meprin metalloproteases are highly expressed at the luminal interface of the intestine and kidney and in certain leukocytes. Meprins cleave a variety of substrates in vitro, including extracellular matrix proteins, adherens junction proteins, and cytokines, and have been implicated in a number of inflammatory diseases. The linkage between results in vitro and pathogenesis, however, has not been elucidated. The present study aimed to determine whether meprins are determinative factors in disrupting the barrier function of the epithelium. Active meprin A or meprin B applied to Madin-Darby canine kidney (MDCK) cell monolayers increased permeability to fluorescein isothiocyanate-dextran and disrupted immunostaining of the tight junction protein occludin but not claudin-4. Meprin A, but not meprin B, cleaved occludin in MDCK monolayers. Experiments with recombinant occludin demonstrated that meprin A cleaves the protein between Gly100 and Ser101 on the first extracellular loop. In vivo experiments demonstrated that meprin A infused into the mouse bladder increased the epithelium permeability to sodium fluorescein. Furthermore, monocytes from meprin knockout mice on a C57BL/6 background were less able to migrate through an MDCK monolayer than monocytes from their wild-type counterparts. These results demonstrate the capability of meprin A to disrupt epithelial barriers and implicate occludin as one of the important targets of meprin A that may modulate inflammation. PMID:23804454

  6. Nicotiana benthamiana α-galactosidase A1.1 can functionally complement human α-galactosidase A deficiency associated with Fabry disease.

    PubMed

    Kytidou, Kassiani; Beekwilder, Jules; Artola, Marta; van Meel, Eline; Wilbers, Ruud H P; Moolenaar, Geri F; Goosen, Nora; Ferraz, Maria J; Katzy, Rebecca; Voskamp, Patrick; Florea, Bogdan I; Hokke, Cornelis H; Overkleeft, Herman S; Schots, Arjen; Bosch, Dirk; Pannu, Navraj; Aerts, Johannes M F G

    2018-04-19

    α-Galactosidases (EC 3.2.1.22) are retaining glycosidases that cleave terminal α-linked galactose residues from glycoconjugate substrates. α-Galactosidases take part in the turnover of cell wall-associated galactomannans in plants and in the lysosomal degradation of glycosphingolipids in animals. Deficiency of human α-galactosidase A (α-Gal A) causes Fabry disease (FD), a heritable, X-linked lysosomal storage disorder, characterized by accumulation of globotriaosylceramide (Gb3) and globotriaosylsphingosine (lysoGb3). Current management of FD involves enzyme-replacement therapy (ERT). An activity-based probe (ABP) covalently labeling the catalytic nucleophile of α-Gal A has been previously designed to study α-galactosidases for use in FD therapy. Here, we report that this ABP labels proteins in Nicotiana benthamiana leaf extracts, enabling the identification and biochemical characterization of an N. benthamiana α-galactosidase we name here A1.1 (gene accession GJZM-1660). The transiently overexpressed and purified enzyme was a monomer lacking N-glycans and was active toward 4-methylumbelliferyl-α-D-galactopyranoside substrate (Km = 0.17 mM) over a broad pH range. A1.1 structural analysis by X-ray crystallography revealed marked similarities with human α-Gal A, even including A1.1's ability to hydrolyze Gb3 and lysoGb3, which are not endogenous in plants. Of note, A1.1 uptake into FD fibroblasts reduced the elevated lysoGb3 levels in these cells, consistent with A1.1 delivery to lysosomes as revealed by confocal microscopy. The ease of production and the features of A1.1, such as stability over a broad pH range, combined with its capacity to degrade glycosphingolipid substrates, warrant further examination of its value as a potential therapeutic agent for ERT-based FD management. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Quantification of equine immunoglobulin A in serum and secretions by a fluorescent bead-based assay.

    PubMed

    Schnabel, Christiane L; Babasyan, Susanna; Freer, Heather; Wagner, Bettina

    2017-06-01

    Only few quantitative reports exist about the concentrations and induction of immunoglobulin A (IgA) in mucosal secretions of horses. Despite this, it is widely assumed that IgA is the predominant immunoglobulin on mucosal surfaces in the horse. Here, two new monoclonal antibodies (mAbs) against equine IgA, clones 84-1 and 161-1, were developed and characterized in detail. Both IgA mAbs specifically bound monomeric and dimeric equine IgA in different applications, such as Western blots and fluorescent bead-based assays. Cross-reactivity with other equine immunoglobulin isotypes was not observed. The new IgA mAb 84-1 was used in combination with the previously characterized anti-equine IgA mAb BVS2 for the development and validation of a fluorescent bead-based assay to quantify total IgA in equine serum and various secretions. The IgA assay's linear detection ranged from 64pg/ml to 1000ng/ml. For the quantification of IgA in serum or in secretions an IgA standard was purified from serum or nasal wash fluid (secretory IgA), respectively. The different standards were needed for accurate IgA quantification in the respective samples taking the different signal intensities of monomeric and dimeric IgA on the florescent bead-based assay into account. IgA was quantified by the bead-based assay established here in different equine samples of healthy adult individuals. In serum the median total IgA was 0.45mg/ml for Thoroughbred horses (TB, n=10) and 1.16mg/ml in Icelandic horses (ICH, n=12). In nasopharyngeal secretions of TB (n=7) 0.13mg/ml median total IgA was measured, and 0.25mg/ml for ICH (n=12). Saliva of ICH (n=6) contained a median of 0.15mg/ml, colostrum of Warmbloods (n=8) a median of 1.89mg/ml IgA. Compared to IgG1 and IgG4/7 quantified in the same samples, IgA appeared as the major immunoglobulin isotype in nasopharyngeal secretions and saliva while it is a minor isotype in serum and colostrum. The newly developed monoclonal antibodies against equine IgA and the

  8. Immunoexpression of cleaved caspase-3 shows lower apoptotic area indices in lip carcinomas than in intraoral cancer.

    PubMed

    Leite, Ana Flávia Schueler de Assumpção; Bernardo, Vagner Gonçalves; Buexm, Luisa Aguirre; Fonseca, Eliene Carvalho da; Silva, Licínio Esmeraldo da; Barroso, Danielle Resende Camisasca; Lourenço, Simone de Queiroz Chaves

    2016-01-01

    This study aimed to evaluate apoptosis by assessing cleaved caspase-3 immunoexpression in hyperplastic, potentially malignant disorder (PMD), and malignant tumors in intraoral and lower lip sites. A retrospective study using paraffin blocks with tissues from patients with inflammatory fibrous hyperplasia (IFH), actinic cheilitis, oral leukoplakia, lower lip and intraoral squamous cell carcinoma (SCC) was performed. The tissues were evaluated by immunohistochemical analysis with anti-cleaved caspase-3 antibody. Apoptotic area index was then correlated with lesion type. From 120 lesions assessed, 55 (46%) were cleaved caspase-3-positive. The SCC samples (n=40) had the highest apoptotic area indices (n=35; 87.5%). Significant differences were detected between SCCs and PMDs (p=0.0003), as well as SCCs and IFHs (p=0.001), regarding caspase-3 immunopositivity. Carcinomas of the lower lip had lower apoptotic area indices than intraoral cancer (p=0.0015). Cleaved caspase-3 immunoexpression showed differences in oral SCCs and PMDs and demonstrated a distinct role of apoptosis in carcinogenesis of intraoral and lower lip cancer. In future, the expression of cleaved caspase-3 with other target molecules in oral cancer may be helpful in delineating the prognosis and treatment of these tumors.

  9. [Effect of NOR1 gene knockdown on the biological behavior of HeLa cells].

    PubMed

    Tan, Yixin; Li, Wenjuan; Yi, Mei; Wang, Wei; Zheng, Pan; Zhang, Haijing; Xiang, Bo; Li, Guiyuan

    2014-08-01

    To explore the effect of the oxidored nitro domain containing protein 1 (NOR1) gene knockdown on the biological behavior of HeLa cells in cervical carcinoma. The recombinant plasmids pSUPER-shNOR1-1, pSUPER-shNOR1-2 and pSUPERscramble, which targeted to NOR1 gene, were constructed by pSUPER.neo+GFP vector, transfected into HeLa cells respectively using Lipofectamine 2000 reagent, and followed by G418 selection. The expression level of NOR1 mRNA and protein were determined by RT-PCR and Western blotting, respectively. Methyl thiazolyl tetrazolium (MTT) assay was performed to determine the growth curve of cell viability. The stable transfectants were treated with H₂O₂ and cell apoptosis was determined by Hoechst 33258 staining and terminal deoxynucleotidyl transferasemediated dUTP nick end labeling (TUNEL) assay. The expression levels of Bcl-2, cleaved caspase 9 and poly ADP-ribose polymerase (PARP) were measured by Western blot. NOR1- knockdown HeLa cells were successfully constructed by transfection of pSUPER-shNOR1-1 or pSUPER-shNOR1-2 plasmids into HeLa cells. MTT assay showed that the silence of endogenous NOR1 in HeLa cells could lead to the increase in cell viability and proliferation, and the inhibition of H₂O₂-induced apoptosis compared with the negative control. Western blot showed that the expression level of active caspase 9 and cleaved PARP was inhibited in NOR1-knockdown cells when they were treated with H₂O₂ while the expression level of Bcl-2 protein increased. Silence of endogenous NOR1 facilitates the cell viability and growth of HeLa cells, and attenuates HeLa cells apoptosis induced by H₂O₂, which might be mediated by up-regulation of Bcl-2 level and down-regulation of the cleaved caspase 9 cascade.

  10. [Clinical significance of analysis of immunoglobulin A levels in saliva].

    PubMed

    Bokor-Bratić, M

    2000-01-01

    plasma cells locally in the salivary glands. There is still little convincing evidence for the origin of predominantly immunoglobulin A secreting plasma cells in salivary glands. DETECTION OF IMMUNOGLOBULIN A IN SALIVA: Radial immunodiffusion (RID) was the most applicable method for detecting salivary immunoglobulin A. However, there are more sensitive and automatic methods such as nephelometry and ELISA. A standard level of immunoglobulin in saliva is still in question since the concentration varies in relation to origin of saliva, method of collection and stimulation of secretion (Table 1). PERIODONTAL DISEASE: Studies of the salivary immunoglobulin A in patients with periodontal disease and healthy persons showed that there are differences which can be used in detection of high-risk groups and individuals. If the bacterial adherence to the mucosa is a prerequisite for bacterial evolution in subgingival or any other region of the oral cavity respectively introduction in periodontitis development, than it is to be presumed that the basic function of salivary immunoglobulin A is inhibition of bacterial adherence rather than antigens destruction. Several bacterial species frequently isolated from the oral cavity of patients with periodontitis have been identified as producers of IgA protease. These enzymes cleave serum IgA and secretory IgA equally well. Additionally, most of the IgA proteases studied have cleaved the A1 and A2 subclass. Several studies have demonstrated that cleavage of human IgA occurs in vivo, resulting in generation of intact Fab alpha and (Fc alpha)2 fragment. Moreover, when bacteria are exposed to Fab alpha fragments released from IgA after cleavage by IgA protease, their surface antigens are likely to be occupied by Fab alpha fragments. These Fab alpha fragments left on the bacterial surface may mediate adhesion. Together, these results indicate that IgA proteases, by promoting adherence, contribute the pathogenic potential of bacteria in the oral

  11. Functional analyses of the three simian hemorrhagic fever virus nonstructural protein 1 papain-like proteases.

    PubMed

    Vatter, Heather A; Di, Han; Donaldson, Eric F; Radu, Gertrud U; Maines, Taronna R; Brinton, Margo A

    2014-08-01

    The N-terminal region of simian hemorrhagic fever virus (SHFV) nonstructural polyprotein 1a is predicted to encode three papain-like proteases (PLP1α, PLP1β, and PLP1γ). Catalytic residues and cleavage sites for each of the SHFV PLP1s were predicted by alignment of the SHFV PLP1 region sequences with each other as well as with those of other arteriviruses, and the predicted catalytic residues were shown to be proximal by homology modeling of the SHFV nsp1s on porcine respiratory and reproductive syndrome virus (PRRSV) nsp1 crystal structures. The functionality of the predicted catalytic Cys residues and cleavage sites was tested by analysis of the autoproteolytic products generated in in vitro transcription/translation reactions done with wild-type or mutant SHFV nsp1 constructs. Cleavage sites were also analyzed by mass spectroscopy analysis of selected immunoprecipitated cleavage products. The data showed that each of the three SHFV PLP1s is an active protease. Cys63 was identified as the catalytic Cys of SHFV PLP1α and is adjacent to an Ala instead of the canonical Tyr observed in other arterivirus PLP1s. SHFV PLP1γ is able to cleave at both downstream and upstream nsp1 junction sites. Although intermediate precursor polyproteins as well as alternative products generated by each of the SHFV PLP1s cleaving at sites within the N-terminal region of nsp1β were produced in the in vitro reactions, Western blotting of SHFV-infected, MA104 cell lysates with SHFV nsp1 protein-specific antibodies detected only the three mature nsp1 proteins. SHFV is unique among arteriviruses in having three N-terminal papain-like protease 1 (PLP1) domains. Other arteriviruses encode one or two active PLP1s. This is the first functional study of the SHFV PLP1s. Analysis of the products of in vitro autoprocessing of an N-terminal SHFV nonstructural 1a polypeptide fragment showed that each of the three SHFV PLP1s is active, and the predicted catalytic Cys residues and cleavage sites

  12. Glycosylation of immunoglobulin A influences its receptor binding.

    PubMed

    Basset, C; Devauchelle, V; Durand, V; Jamin, C; Pennec, Y L; Youinou, P; Dueymes, M

    1999-12-01

    Immunoglobulin A (IgA), which is heavily glycosylated, interacts with a variety of receptors, e.g. the asialoglycoprotein receptor (ASGP-R), which binds terminal galactose residues, and the Fcalpha receptor (FcalphaRI). It has thus been proposed that elevated serum levels of IgA in primary Sjögren's syndrome (pSS) are caused by its defective clearance. To test this hypothesis, we developed a method (based on sialyl transferases eluted from a hepatoma cell line) to increase the amount of sialic acid (SA) on IgA, and used a battery of IgA1- and IgA2-specific glycosidases to reduce this amount. Binding of IgA1 and IgA2 to ASGP-R and FcalphaRI was found to be sugar dependent because oversialylated IgA bound less than native or desialylated IgA. However, individual sugars did not play a direct role in this binding. Given that IgA are oversialylated in pSS, defective clearance of IgA may indeed be ascribed to an excess of SA in IgA1 and IgA2.

  13. Mangiferin Enhanced Autophagy via Inhibiting mTORC1 Pathway to Prevent High Glucose-Induced Cardiomyocyte Injury.

    PubMed

    Hou, Jun; Zheng, Dezhi; Xiao, Wenjing; Li, Dandan; Ma, Jie; Hu, Yonghe

    2018-01-01

    Mangiferin functions as a perfect anti-oxidative compound in the diabetic heart, however, the exact mechanism remains to be elucidated. Here, we show the cardioprotective effect of mangiferin under high glucose-induced cardiotoxic condition mainly contributed to enhanced autophagy via suppressing mTORC1 downstream signal transduction. Primary neonatal rat cardiomyocytes were cultured to detect myocytes injury, autophagy, and related signal transduction under different doses of glucose and mangiferin treatment. High glucose (30 mM) reduced autophagic flux, and increased myocyte apoptosis and death compared with normal glucose (5.5 mM) as determined by variation of autophagy markers LC3-II, p62, parkin, GFP-LC3, or mRFP-LC3 fluorescence puncta, cell viability, cleaved caspase 3, cleaved PARP apoptosis indices, reactive oxygen species (ROS), MAO, and PI death indices. Conversely, mangiferin inhibited hyperglycemia associated oxidative stress by reducing ROS, MAO, cleaved caspase 3, and cleaved PARP generation, reestablishing cell viability, mitochondrial membrane potential, and enhancing autophagic flux, thereby preventing myocytes from high glucose-induced toxicity. Furthermore, cardioprotection with mangiferin was potentially related to the decreased mTOR phosphorylation and suppression of mTORC1 downstream signaling pathway. These data indicated the valuable effects of mangiferin on regulation of cardiac autophagy and pointed to the promising utilization for hyperglycemia control.

  14. The nature of the air-cleaved mica surface

    NASA Astrophysics Data System (ADS)

    Christenson, Hugo K.; Thomson, Neil H.

    2016-06-01

    The accepted image of muscovite mica is that of an inert and atomically smooth surface, easily prepared by cleavage in an ambient atmosphere. Consequently, mica is extensively used a model substrate in many fundamental studies of surface phenomena and as a substrate for AFM imaging of biomolecules. In this review we present evidence from the literature that the above picture is not quite correct. The mica used in experimental work is almost invariably cleaved in laboratory air, where a reaction between the mica surface, atmospheric CO2 and water occurs immediately after cleavage. The evidence suggests very strongly that as a result the mica surface becomes covered by up to one formula unit of K2CO3 per nm2, which is mobile under humid conditions, and crystallises under drier conditions. The properties of mica in air or water vapour cannot be fully understood without reference to the surface K2CO3, and many studies of the structure of adsorbed water on mica surfaces may need to be revisited. With this new insight, however, the air-cleaved mica should provide exciting opportunities to study phenomena such as two-dimensional ion diffusion, electrolyte effects on surface conductivity, and two-dimensional crystal nucleation.

  15. Expression of membrane-type 1 matrix metalloproteinase (MT1-MMP) on prostate cancer cell lines.

    PubMed

    Nagakawa, O; Murakami, K; Yamaura, T; Fujiuchi, Y; Murata, J; Fuse, H; Saiki, I

    2000-07-31

    Membrane-type metalloproteinase-1 (MT1-MMP) is a transmembrane metalloproteinase, which activates proMMP-2 and expressed on the cell surface in many invasive cancer cells. We investigated the expression of MT1-MMP in prostate cancer cell lines. MT1-MMP protein and mRNA were expressed in PC-3, DU-145 and TSU-pr1 cells (androgen-independent prostate cancer cell lines), but in LNCaP cells (androgen-dependent prostate cancer cell line). MT1-MMP protein was negative and mRNA was low to detect by RT-PCR. Cell lysate of PC-3 cleaved proMMP-2 to the active form. In addition, both hepatocyte growth factor (HGF) and gastrin-releasing peptide (GRP) increased Matrigel invasion and induced the expression of MT1-MMP protein in DU-145 prostate cancer cells. These results suggest that MT1-MMP is indeed the tumor-specific activator of proMMP-2 in androgen-independent prostate cancer cells and plays an important role in the invasive properties of prostate cancer cells.

  16. Effects of the HIF1 inhibitor, echinomycin, on growth and NOTCH signalling in leukaemia cells.

    PubMed

    Yonekura, Satoru; Itoh, Mai; Okuhashi, Yuki; Takahashi, Yusuke; Ono, Aya; Nara, Nobuo; Tohda, Shuji

    2013-08-01

    To examine the effects of echinomycin, a compound that inhibits DNA-binding activity of hypoxia-inducible factor-1 (HIF1), on leukaemia cell growth. Three acute myeloid leukaemia cell lines and three T-lymphoblastic leukaemia cell lines were cultured with echinomycin. Cell growth, mRNA and protein expression levels were examined by WST-1 assay, reverse-transcription polymerase chain reaction and immunoblotting, respectively. HIF1α protein was expressed in all cell lines under normoxia. Treatment with echinomycin suppressed cell growth and induced apoptosis in association with decreased mRNA expression of HIF1 targets, glucose transporter-1 (GLUT1) and B-cell CLL/lymphoma-2 (BCL2). Echinomycin also suppressed the protein expression of NOTCH1, cleaved NOTCH1, v-myc myelocytomatosis viral oncogene homolog (MYC), v-akt murine thymoma viral oncogene homolog-1 (AKT), phosphorylated AKT, mechanistic target of rapamycin (mTOR), and phosphorylated mTOR and increased that of cleaved caspase-3 in some cell lines. Echinomycin suppresses leukaemia cell growth in association with reduced NOTCH1 expression. This is the first report to show that HIF inhibitor treatment suppresses NOTCH1 signalling. HIF inhibitors could be novel candidates for a molecular-targeted therapy against leukaemia.

  17. Role of Serum Mycoplasma pneumoniae IgA, IgM, and IgG in the Diagnosis of Mycoplasma pneumoniae-Related Pneumonia in School-Age Children and Adolescents

    PubMed Central

    Lee, Wei-Ju; Huang, Eng-Yen; Tsai, Chih-Min; Kuo, Kuang-Che; Huang, Yi-Chuan; Hsieh, Kai-Sheng; Niu, Chen-Kuang

    2016-01-01

    ABSTRACT Mycoplasma pneumoniae is an important causative pathogen of community-acquired pneumonia in children. Rapid and reliable laboratory diagnosis of M. pneumoniae infection is important so that appropriate antibiotic treatment can be initiated to reduce the misuse of drugs and resistance rates. Anti-M. pneumoniae immunoglobulin M (IgM) is an indicator of recent primary infection but can persist for several months after initial infection. It has been suggested that anti-M. pneumoniae immunoglobulin A (IgA) can be a reliable indicator for recent M. pneumoniae infection in adults. We investigated the clinical diagnostic value of M. pneumoniae IgA in school-age children and adolescents with M. pneumoniae-related pneumonia. Eighty children with pneumonia and seropositive for M. pneumoniae IgM or with a 4-fold increase of anti-M. pneumoniae immunoglobulin G (IgG) were enrolled from May 2015 to March 2016. The titers of M. pneumoniae IgA, IgM, and IgG, the clinical features, and laboratory examinations of blood, C-reactive protein, and liver enzymes were analyzed. The initial positivity rates for M. pneumoniae IgM and IgA upon admission to the hospital were 63.6 and 33.8%, respectively. One week after admission, the cumulative positivity rates for M. pneumoniae IgM and IgA increased to 97.5 and 56.3%, respectively. Detection of M. pneumoniae IgM was more sensitive than detection of M. pneumoniae IgA for the diagnosis of M. pneumoniae-related pneumonia in school-age children and adolescents; however, paired sera are necessary for a more accurate diagnosis. PMID:27760779

  18. S1 of distinct IBV population expressed from recombinant adenovirus confers protection against challenge.

    PubMed

    Toro, H; Zhang, J F; Gallardo, R A; van Santen, V L; van Ginkel, F W; Joiner, K S; Breedlove, C

    2014-06-01

    Protective properties of three distinct infectious bronchitis virus (IBV) Ark Delmarva poultry industry (ArkDPI) S1 proteins encoded from replication-defective recombinant adenovirus vectors were investigated. Using a suboptimal dose of each recombinant virus, we demonstrated that IBV S1 amino acid sequences showing > or = 95.8% amino acid identity to the S1 of the challenge strain differed in their ability at conferring protection. Indeed, the S1 sequence of the IBV population previously designated C4 (AdIBVS1.C4), which protected the most poorly, differs from the S1 sequence of population C2 (AdIBVS1.C2), which provided the highest protection, only at amino acid position 56. The fact that a change in one amino acid in this region significantly altered the induction of a protective immune response against this protein provides evidence that the first portion of S1 displays relevant immunoprotective epitopes. Use of an optimal dose of AdIBVS1.C2 effectively protected chickens from clinical signs and significantly reduced viral load after IBV Ark virulent challenge. Moreover, increased numbers of both IgA and IgG IBV-specific antibody secreting lymphocytes were detected in the spleen after challenge. The increased response detected for both IgA and IgG lymphocytes after challenge might be explained by vaccine-induced B memory cells. The fact that a single vaccination with Ad/IBVS1.C2 provides protection against IBV challenge is promising, because Ad-vectored vaccines can be mass delivered by in ovo inoculation using automated in ovo injectors.

  19. Inducible Transgenic Models of BRCA1 Function

    DTIC Science & Technology

    1999-10-01

    inducible expression vectors were created to conditionally express four different hammerhead ribozymes designed to specifically cleave the Brca...transcript. Hammerhead ribozymes are catalytic RNAs that efficiently cleave RNA and thereby down- regulate gene expression. Hammerhead ribozymes can cleave...any RNA containing its 5’-UH-3’ consensus sequence where U can be replaced by a C, and H=C, U or A. Hammerhead ribozymes effectively and selectively

  20. Inducible Transgenic Models of BRCA1 Function

    DTIC Science & Technology

    2000-10-01

    four different hammerhead ribozymes designed to specifically cleave the Brcal transcript. Hammerhead ribozymes are catalytic RNAs that efficiently...cleave RNA and thereby down- regulate gene expression. Hammerhead ribozymes can cleave any RNA containing a 5’-UH-3’ consensus sequence where U can be...replaced by C, and H=C, U or A. Hammerhead ribozymes have been shown to effectively and selectively inhibit gene expression in bacteria, plants, cell