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Sample records for ignar antibodies evidence

  1. Maturation of Shark Single-Domain (IgNAR) Antibodies: Evidence for Induced-Fit Binding

    SciTech Connect

    Stanfield, R.L.; Dooley, H.; Verdino, P.; Flajnik, M.F.; Wilson, I.A.; /Scripps Res. Inst. /Maryland U.

    2007-07-13

    Sharks express an unusual heavy-chain isotype called IgNAR, whose variable regions bind antigen as independent soluble domains. To further probe affinity maturation of the IgNAR response, we structurally characterized the germline and somatically matured versions of a type II variable (V) region, both in the presence and absence of its antigen, hen egg-white lysozyme. Despite a disulfide bond linking complementarity determining regions (CDRs) 1 and 3, both germline and somatically matured V regions displayed significant structural changes in these CDRs upon complex formation with antigen. Somatic mutations in the IgNAR V region serve to increase the number of contacts with antigen, as reflected by a tenfold increase in affinity, and one of these mutations appears to stabilize the CDR3 region. In addition, a residue in the HV4 loop plays an important role in antibody-antigen interaction, consistent with the high rate of somatic mutations in this non-CDR loop.

  2. The Shark Strikes Twice: Hypervariable Loop 2 of Shark IgNAR Antibody Variable Domains and Its Potential to Function as an Autonomous Paratope.

    PubMed

    Zielonka, Stefan; Empting, Martin; Könning, Doreen; Grzeschik, Julius; Krah, Simon; Becker, Stefan; Dickgießer, Stephan; Kolmar, Harald

    2015-08-01

    In this present study, we engineered hypervariable loop 2 (HV2) of the IgNAR variable domain in a way that it solely facilitates antigen binding, potentially functioning as an autonomous paratope. For this, the surface-exposed loop corresponding to HV2 was diversified and antigen-specific variable domain of IgNAR antibody (vNAR) molecules were isolated by library screening using yeast surface display (YSD) as platform technology. An epithelial cell adhesion molecule (EpCAM)-specific vNAR was used as starting material, and nine residues in HV2 were randomized. Target-specific clones comprising a new HV2-mediated paratope were isolated against cluster of differentiation 3ε (CD3ε) and human Fcγ while retaining high affinity for EpCAM. Essentially, we demonstrate that a new paratope comprising moderate affinities against a given target molecule can be engineered into the vNAR scaffold that acts independent of the original antigen-binding site, composed of complementarity-determining region 3 (CDR3) and CDR1. PMID:26003538

  3. Isolation of a pH-Sensitive IgNAR Variable Domain from a Yeast-Displayed, Histidine-Doped Master Library.

    PubMed

    Könning, Doreen; Zielonka, Stefan; Sellmann, Carolin; Schröter, Christian; Grzeschik, Julius; Becker, Stefan; Kolmar, Harald

    2016-04-01

    In recent years, engineering of pH-sensitivity into antibodies as well as antibody-derived fragments has become more and more attractive for biomedical and biotechnological applications. Herein, we report the isolation of the first pH-sensitive IgNAR variable domain (vNAR), which was isolated from a yeast-displayed, semi-synthetic master library. This strategy enables the direct identification of pH-dependent binders from a histidine-enriched CDR3 library. Displayed vNAR variants contained two histidine substitutions on average at random positions in their 12-residue CDR3 loop. Upon screening of seven rounds against the proof-of-concept target EpCAM (selection for binding at pH 7.4 and decreased binding at pH 6.0), a single clone was obtained that showed specific and pH-dependent binding as characterized by yeast surface display and biolayer interferometry. Potential applications for such pH-dependent vNAR domains include their employment in tailored affinity chromatography, enabling mild elution protocols. Moreover, utilizing a master library for the isolation of pH-sensitive vNAR variants may be a generic strategy to obtain binding entities with prescribed characteristics for applications in biotechnology, diagnostics, and therapy. PMID:26838965

  4. Antibody

    MedlinePlus

    An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples ... microorganisms (bacteria, fungi, parasites, and viruses) and chemicals. Antibodies may be produced when the immune system mistakenly ...

  5. Evidence of a saturable hepatic receptor for mouse monoclonal antibodies

    SciTech Connect

    De Nardo, G.L.; De Nardo, S.J.; Peng, J.S.; O'Grady, L.F.; Mills, S.L.; Epstein, A.L.; Cardiff, R.D.

    1985-05-01

    Monoclonal antibodies (MAb) can be labeled with I-123 at high specific activities, so that large amounts of radioactivity attached to small amounts of protein can be injected for radioimmunoimaging. This conserves antibody and decreases the opportunity for foreign protein reactions and target tissue binding site saturation. In order to assess the effects on pharmacokinetics and imaging, the authors administered microgram amounts of I-123-MAb (Lyn-1, IgG2a or B6.01, IgGl with and following 4-5 milligram preloading with MAb on separate occasions to 4 patients with a target tumor (B cell lymphoma) and 2 patients without a target tumor (breast cancer). Pharmacokinetics were observed in blood and urine by counting whole samples and HPLC fractions of these samples and in organs by serial imaging. Early blood clearance and urinary excretion were faster after injection of microgram amounts of MAb, but subsequently were comparable to those obtained after preload. This paper concludes that the amount of administered MAb dramatically influences the pharmacokinetics of mouse MAb. Saturable hepatic Fc receptors are probably the source of these observations. Reports of accelerated deiodination of MAb are related to this phenomenon. Optimal imaging and treatment with MAb requires saturation of these hepatic receptors.

  6. Leptospiral Antibodies in Cattle in Alberta and Evidence of an Emerging Serovar

    PubMed Central

    Kingscote, Barbara

    1988-01-01

    Antibodies to Leptospira interrogans serovars hardjo and pomona were present in 8.3% and 0.5% of sera respectively, from adult female cattle in Alberta surveyed in 1984-85. Criterion for a positive serum sample was 50% agglutination at 1/100 dilution in the microscopic agglutination test. A positive herd contained one or more cows with positive serum. Prevalences were calculated on sample sizes that would give 80-95% reliability. Hardjo antibody prevalences and hardjo-positive herd prevalences were 0-53.9% and 0-83.3%, respectively, among 65 municipalities surveyed. Pomona prevalences by comparison were 0-3.4% and 0-11.7% respectively. Hardjo had increased significantly since 1980-82, and antibodies were found throughout the province. Pomona occurred mainly in southeastern Alberta, where it was isolated from cattle, swine and skunks. Hardjo was isolated only from cattle and it was found in many areas. Antibodies to icterohaemorrhagiae were present in 0.4% of sera from parts of Alberta surveyed in 1980; evidence of the presence of leptospires related to this serovar in bovine and porcine urinary tracts was obtained by immunofluorescence. ImagesFigure 3. PMID:17423101

  7. Aspergillus fumigatus-specific antibodies in allergic bronchopulmonary aspergillosis and aspergilloma: evidence for a polyclonal antibody response.

    PubMed Central

    Brummund, W; Resnick, A; Fink, J N; Kurup, V P

    1987-01-01

    Patients with the Aspergillus-induced diseases allergic bronchopulmonary aspergillosis (ABPA), aspergilloma (fungus ball), and Aspergillus skin test-positive asthma were differentiated immunologically by radioimmunoassay based on their total immunoglobulin E (IgE) and Aspergillus fumigatus-specific IgE levels. In this study, a new, highly sensitive biotin-avidin-linked immunosorbent assay was used to evaluate A. fumigatus-specific antibodies of all immunoglobulin classes. Studied populations included 13 patients with ABPA, 12 with aspergilloma, 9 with Aspergillus skin test-positive asthma, and 9 normal individuals without asthma. A. fumigatus-specific antibodies of all classes were elevated in patients with ABPA, variably elevated in those with aspergilloma, and lowest in the other two groups. This assay demonstrated significantly higher specific IgE antibody levels in the ABPA group over those of the other groups, even with 1:1,000 dilutions of the sera. This study demonstrated that ABPA is a disease characterized by a polyclonal antibody response to Aspergillus antigen and not just a response to IgE and IgG antibody classes. The measurement of other antibody classes, particularly IgD and IgA, could enhance the immunodiagnosis of ABPA. The biotin-avidin-linked immunosorbent assay was found to be a highly sensitive assay that can be a clinically useful alternative to radioimmunoassay in the measurement of A. fumigatus-specific antibodies. PMID:3539998

  8. Rigidity Emerges during Antibody Evolution in Three Distinct Antibody Systems: Evidence from QSFR Analysis of Fab Fragments

    PubMed Central

    Li, Tong; Tracka, Malgorzata B.; Uddin, Shahid; Casas-Finet, Jose; Jacobs, Donald J.; Livesay, Dennis R.

    2015-01-01

    The effects of somatic mutations that transform polyspecific germline (GL) antibodies to affinity mature (AM) antibodies with monospecificity are compared among three GL-AM Fab pairs. In particular, changes in conformational flexibility are assessed using a Distance Constraint Model (DCM). We have previously established that the DCM can be robustly applied across a series of antibody fragments (VL to Fab), and subsequently, the DCM was combined with molecular dynamics (MD) simulations to similarly characterize five thermostabilizing scFv mutants. The DCM is an ensemble based statistical mechanical approach that accounts for enthalpy/entropy compensation due to network rigidity, which has been quite successful in elucidating conformational flexibility and Quantitative Stability/Flexibility Relationships (QSFR) in proteins. Applied to three disparate antibody systems changes in QSFR quantities indicate that the VH domain is typically rigidified, whereas the VL domain and CDR L2 loop become more flexible during affinity maturation. The increase in CDR H3 loop rigidity is consistent with other studies in the literature. The redistribution of conformational flexibility is largely controlled by nonspecific changes in the H-bond network, although certain Arg to Asp salt bridges create highly localized rigidity increases. Taken together, these results reveal an intricate flexibility/rigidity response that accompanies affinity maturation. PMID:26132144

  9. Structural insights and biomedical potential of IgNAR scaffolds from sharks

    PubMed Central

    Zielonka, Stefan; Empting, Martin; Grzeschik, Julius; Könning, Doreen; Barelle, Caroline J; Kolmar, Harald

    2015-01-01

    In addition to antibodies with the classical composition of heavy and light chains, the adaptive immune repertoire of sharks also includes a heavy-chain only isotype, where antigen binding is mediated exclusively by a small and highly stable domain, referred to as vNAR. In recent years, due to their high affinity and specificity combined with their small size, high physicochemical stability and low-cost of production, vNAR fragments have evolved as promising target-binding scaffolds that can be tailor-made for applications in medicine and biotechnology. This review highlights the structural features of vNAR molecules, addresses aspects of their generation using immunization or in vitro high throughput screening methods and provides examples of therapeutic, diagnostic and other biotechnological applications. PMID:25523873

  10. Atypical antigen recognition mode of a shark immunoglobulin new antigen receptor (IgNAR) variable domain characterized by humanization and structural analysis.

    PubMed

    Kovalenko, Oleg V; Olland, Andrea; Piché-Nicholas, Nicole; Godbole, Adarsh; King, Daniel; Svenson, Kristine; Calabro, Valerie; Müller, Mischa R; Barelle, Caroline J; Somers, William; Gill, Davinder S; Mosyak, Lidia; Tchistiakova, Lioudmila

    2013-06-14

    The immunoglobulin new antigen receptors (IgNARs) are a class of Ig-like molecules of the shark immune system that exist as heavy chain-only homodimers and bind antigens by their single domain variable regions (V-NARs). Following shark immunization and/or in vitro selection, V-NARs can be generated as soluble, stable, and specific high affinity monomeric binding proteins of ∼12 kDa. We have previously isolated a V-NAR from an immunized spiny dogfish shark, named E06, that binds specifically and with high affinity to human, mouse, and rat serum albumins. Humanization of E06 was carried out by converting over 60% of non-complementarity-determining region residues to those of a human germ line Vκ1 sequence, DPK9. The resulting huE06 molecules have largely retained the specificity and affinity of antigen binding of the parental V-NAR. Crystal structures of the shark E06 and its humanized variant (huE06 v1.1) in complex with human serum albumin (HSA) were determined at 3- and 2.3-Å resolution, respectively. The huE06 v1.1 molecule retained all but one amino acid residues involved in the binding site for HSA. Structural analysis of these V-NARs has revealed an unusual variable domain-antigen interaction. E06 interacts with HSA in an atypical mode that utilizes extensive framework contacts in addition to complementarity-determining regions that has not been seen previously in V-NARs. On the basis of the structure, the roles of various elements of the molecule are described with respect to antigen binding and V-NAR stability. This information broadens the general understanding of antigen recognition and provides a framework for further design and humanization of shark IgNARs. PMID:23632026

  11. Evidence for a novel human-specific xeno-auto-antibody response against vascular endothelium.

    PubMed

    Pham, Tho; Gregg, Christopher J; Karp, Felix; Chow, Renee; Padler-Karavani, Vered; Cao, Hongzhi; Chen, Xi; Witztum, Joseph L; Varki, Nissi M; Varki, Ajit

    2009-12-10

    Humans are genetically unable to synthesize the common mammalian sialic acid N-glycolylneuraminic acid (Neu5Gc). However, Neu5Gc can be metabolically incorporated and covalently expressed on cultured human cell surfaces. Meanwhile, humans express varying and sometimes high titers of polyclonal anti-Neu5Gc antibodies. Here, a survey of human tissues by immunohistochemistry with both a monospecific chicken anti-Neu5Gc antibody and with affinity-purified human anti-Neu5Gc antibodies demonstrates endothelial expression of Neu5Gc, likely originating from Neu5Gc-rich foods like red meats. We hypothesized that the combination of Neu5Gc incorporation and anti-Neu5Gc antibodies can induce endothelial activation. Indeed, the incubation of high-titer human sera with Neu5Gc-fed endothelial cells led to Neu5Gc-dependent antibody binding, complement deposition, endothelial activation, selectin expression, increased cytokine secretion, and monocyte binding. The proinflammatory cytokine tumor necrosis factor-alpha also selectively enhanced human anti-Neu5Gc antibody reactivity. Anti-Neu5Gc antibodies affinity-purified from human serum also directed Neu5Gc-dependent complement deposition onto cultured endothelial cells. These data indicate a novel human-specific mechanism in which Neu5Gc-rich foods deliver immunogenic Neu5Gc to the endothelium, giving anti-Neu5Gc antibody- and complement-dependent activation, and potentially contributing to human vascular pathologies. In the case of atherosclerosis, Neu5Gc is present both in endothelium overlying plaques and in subendothelial regions, providing multiple pathways for accelerating inflammation in this disease. PMID:19828701

  12. Immune escape by human immunodeficiency virus type 1 from neutralizing antibodies: evidence for multiple pathways.

    PubMed Central

    Watkins, B A; Reitz, M S; Wilson, C A; Aldrich, K; Davis, A E; Robert-Guroff, M

    1993-01-01

    Sera from many HIV-1-infected individuals contain broadly reactive, specific neutralizing antibodies. Despite their broad reactivity, variant viruses, resistant to neutralization, can be selected in vitro in the presence of such antisera. We have previously shown that neutralization resistance of an escape mutant with an amino acid substitution in the transmembrane protein (A582T) occurs because of alteration of a conformational epitope that is recognized by neutralizing antibodies directed against the CD4 binding site. In this report we demonstrate that immune escape via a single-amino-acid substitution (A281V) within a conserved region of the envelope glycoprotein gp120 confers neutralization resistance against a broadly reactive neutralizing antiserum from a seropositive individual. We show this alteration affects V3 and additional regions unrelated to V3 or the CD4 binding site. Together with previous studies on escape mutants selected in vitro, our findings suggest that immune-selective pressure can arise by multiple pathways. PMID:7693973

  13. Humans Have Antibodies against a Plant Virus: Evidence from Tobacco Mosaic Virus

    PubMed Central

    Liu, Ruolan; Vaishnav, Radhika A.; Roberts, Andrew M.; Friedland, Robert P.

    2013-01-01

    Tobacco mosaic virus (TMV), a widespread plant pathogen, is found in tobacco (including cigarettes and smokeless tobacco) as well as in many other plants. Plant viruses do not replicate or cause infection in humans or other mammals. This study was done to determine whether exposure to tobacco products induces an immune response to TMV in humans. Using a sandwich ELISA assay, we detected serum anti-TMV antibodies (IgG, IgG1, IgG3, IgG4, IgA, and IgM) in all subjects enrolled in the study (20 healthy smokers, 20 smokeless-tobacco users, and 20 non-smokers). Smokers had a higher level of serum anti-TMV IgG antibodies than non-smokers, while the serum level of anti-TMV IgA from smokeless tobacco users was lower than smokers and non-smokers. Using bioinformatics, we also found that the human protein TOMM40L (an outer mitochondrial membrane 40 homolog – like translocase) contains a strong homology of six contiguous amino acids to the TMV coat protein, and TOMM40L peptide exhibited cross-reactivity with anti-TMV antibodies. People who smoke cigarettes or other tobacco products experience a lower risk of developing Parkinson’s disease, but the mechanism by which this occurs is unclear. Our results showing molecular mimicry between TMV and human TOMM40L raise the question as to whether TMV has a potential role in smokers against Parkinson’s disease development. The potential mechanisms of molecular mimicry between plant viruses and human disease should be further explored. PMID:23573274

  14. Monoclonal antibody evidence for structural similarities between the central rod regions of actinin and dystrophin.

    PubMed

    Nguyen, T M; Ellis, J M; Ginjaar, I B; van Paassen, M M; van Ommen, G J; Moorman, A F; Cartwright, A J; Morris, G E

    1990-10-15

    A monoclonal antibody, MANDYS141, binds to both dystrophin and actinin on Western blots (SDS-denatured), but only to actinin in frozen sections of human muscle (native conformation). It differs from a polyclonal cross-reacting antiserum in that it binds to several muscle isoforms of actinin (smooth, fast and slow) from man, mouse and chicken and recognises a quite different part of the proposed triple-helical region of dystrophin (amino acids 1750-2248). The results suggest that structural homologies between actinin and dystrophin occur more than once in their central helical regions and provide experimental support for an actinin-like central rod model for dystrophin. PMID:1699800

  15. Ara h 1 protein-antibody dissociation study: evidence for binding inhomogeneities on a molecular scale.

    PubMed

    Pérez-Ruiz, E; Spasic, D; Gils, A; van IJzendoorn, L J; Prins, M W J; Lammertyn, J

    2015-09-25

    The characterization of biomolecular interactions is essential when designing novel biosensors, since the interaction between the bioreceptor and the ligand determines important biosensing parameters such as sensitivity and selectivity. In this paper we study the interaction of the trimeric Ara h 1 protein with a monoclonal anti-Ara h 1 antibody by means of magnetic force-induced dissociation. The proteins were bound to magnetic particles and polystyrene surfaces by EDC/NHS reaction chemistry and by physisorption, respectively. Two different molecular configurations have been investigated, with either the Ara h 1 protein on the particles or the Ara h 1 protein on the polystyrene surface. A model with a Gaussian distribution of energy barriers for dissociation gives an adequate description for the measured multi-exponential decays. We hypothesize that distributions of molecular orientations as well as experimentally induced variations may underlay the observed distributions. The two molecular configurations show a different peak value of the energy distribution. Similarly, SPR experiments for two distinct configurations (either Ara h 1 protein on the surface, or anti-Ara h 1 antibody on the surface) also show clear differences in dissociation behavior. We hypothesize that the multivalency of the involved molecules leads to different modes of binding. The results of this work highlight the importance of molecular inhomogeneities when studying the interaction processes of biomolecular complexes. PMID:25686720

  16. Serological evidence of antibodies to Neospora caninum in stray and owned Grenadian dogs.

    PubMed

    Sharma, R; Kimmitt, T; Tiwari, K; Chikweto, A; Thomas, D; Lanza Perea, M; Bhaiyat, M I

    2015-06-01

    Neospora caninum causes abortion in cattle and neuromuscular disease in dogs, world wide. Cattle become infected by ingesting oocysts voided by dogs. The aim of this study was to estimate the seroprevalence of Neospora caninum in two populations of dogs (stray and owned) in Grenada, West Indies. Sera were collected from 625 dogs from all parishes in Grenada. Three hundred and sixty eight dogs were stray, while 257 dogs were owned. Sera were tested for the presence of antibodies against N. caninum using an indirect enzyme linked immunosorbant assay (ELISA) IDvet, France. Antibodies to N. caninum were found in 6 (1.6%) (95% confidence interval (CI): 0.32% to 2.88%) of the stray dogs and in 3 (1.2%, 95% CI: 0.13% to 2.53%) of the owned dogs. Seroprevalence did not differ significantly between the two populations (p=0.74) and between the males and females (p=1). These results suggest that the prevalence of N. caninum infection in dogs in Grenada is low. PMID:26691257

  17. Positive hepatitis B virus core antibody in HIV infection--false positive or evidence of previous infection?

    PubMed

    Pallawela, S N S; Sonnex, C; Mabayoje, D; Bloch, E; Chaytor, S; Johnson, M A; Carne, C; Webster, D P

    2015-02-01

    Isolated HBV core antibody (anti-HBc) is defined as the presence of anti-HBc with a negative HBV surface antigen (HBsAg) and HBV surface antibody (anti-HBs <10 IU/l). In patients infected with HIV with isolated anti-HBc, the aim was to determine: The prevalence of isolated positive anti-HBc; The most effective method of identifying which patients have had previous Hepatitis B Virus (HBV) infection; The prevalence of false positive anti-HBc. HBV serology results were identified from 539 patients infected with HIV sampled between January 2010 and December 2012. In those with an isolated anti-HBc and negative anti-HBe, a second anti-HBc test was carried out using a different assay. Samples were also screened for HBV DNA. The anti-retroviral regimens at time of screening were documented. 101/539 had an isolated anti-HBc. Of these, 32 (32%) had a positive anti-HBe (including 1 equivocal) and 69(68%) were anti-HBe negative. Of those negative for anti-HBe, 32 were tested for both DNA and a second anti-HBc. Of these 26 (81%) were on cART at time of HBV testing, with 25 (78%) on ART with anti-HBV activity. The prevalence of isolated anti-HBc was 19%. Only 32% were also anti-HBe positive, whereas 97% of those anti-HBe negative were positive on a second anti-HBc assay suggesting lack of utility of anti-HBe in resolving serological quandaries. One subject (3%) had a false positive anti-HBc. There was no evidence of chronic HBV but 78% patients were on HBV-suppressive combination anti-retroviral therapy. PMID:25174739

  18. Epitope mapping by a Wnt-blocking antibody: evidence of the Wnt binding domain in heparan sulfate.

    PubMed

    Gao, Wei; Xu, Yongmei; Liu, Jian; Ho, Mitchell

    2016-01-01

    Heparan sulfate (HS) is a polysaccharide known to modulate many important biological processes, including Wnt signaling. However, the biochemical interaction between HS and Wnt molecules is not well characterized largely due to the lack of suitable methods. To determine the Wnt binding domain in HS, we used a Wnt signaling-inhibitory antibody (HS20) and a panel of synthetic HS oligosaccharides with distinct lengths and sulfation modifications. We found that the binding of HS20 to heparan sulfate required sulfation at both the C2 position (2-O-sulfation) and C6 position (6-O-sulfation). The oligosaccharides with the greatest competitive effect for HS20 binding were between six and eight saccharide residues in length. Additionally, a four residue-long oligosaccharide could also be recognized by HS20 if an additional 3-O-sulfation modification was present. Furthermore, similar oligosaccharides with 2-O, 6-O and 3-O-sulfations showed inhibition for Wnt activation. These results have revealed that HS20 and Wnt recognize a HS structure containing IdoA2S and GlcNS6S, and that the 3-O-sulfation in GlcNS6S3S significantly enhances the binding of both HS20 and Wnt. This study provides the evidence for identifying the Wnt binding domain in HS and suggests a therapeutic approach to target the interaction of Wnt and HS in cancer and other diseases. PMID:27185050

  19. Epitope mapping by a Wnt-blocking antibody: evidence of the Wnt binding domain in heparan sulfate

    PubMed Central

    Gao, Wei; Xu, Yongmei; Liu, Jian; Ho, Mitchell

    2016-01-01

    Heparan sulfate (HS) is a polysaccharide known to modulate many important biological processes, including Wnt signaling. However, the biochemical interaction between HS and Wnt molecules is not well characterized largely due to the lack of suitable methods. To determine the Wnt binding domain in HS, we used a Wnt signaling-inhibitory antibody (HS20) and a panel of synthetic HS oligosaccharides with distinct lengths and sulfation modifications. We found that the binding of HS20 to heparan sulfate required sulfation at both the C2 position (2-O-sulfation) and C6 position (6-O-sulfation). The oligosaccharides with the greatest competitive effect for HS20 binding were between six and eight saccharide residues in length. Additionally, a four residue-long oligosaccharide could also be recognized by HS20 if an additional 3-O-sulfation modification was present. Furthermore, similar oligosaccharides with 2-O, 6-O and 3-O-sulfations showed inhibition for Wnt activation. These results have revealed that HS20 and Wnt recognize a HS structure containing IdoA2S and GlcNS6S, and that the 3-O-sulfation in GlcNS6S3S significantly enhances the binding of both HS20 and Wnt. This study provides the evidence for identifying the Wnt binding domain in HS and suggests a therapeutic approach to target the interaction of Wnt and HS in cancer and other diseases. PMID:27185050

  20. Selection of cell lines resistant to anti-transferrin receptor antibody: evidence for a mutation in transferrin receptor.

    PubMed Central

    Lesley, J F; Schulte, R J

    1984-01-01

    Some anti-murine transferrin receptor monoclonal antibodies block iron uptake in mouse cell lines and inhibit cell growth. We report here the selection and characterization of mutant murine lymphoma cell lines which escape this growth inhibition by anti-transferrin receptor antibody. Growth assays and immunoprecipitation of transferrin receptor in hybrids between independently derived mutants or between mutants and antibody-susceptible parental cell lines indicate that all of the selected lines have a similar genetic alteration that is codominantly expressed in hybrids. Anti-transferrin receptor antibodies and transferrin itself still bind to the mutant lines with saturating levels and Kd values very similar to those of the parental lines. However, reciprocal clearing experiments by immunoprecipitation and reciprocal blocking of binding to the cell surface with two anti-transferrin receptor antibodies indicate that the mutant lines have altered a fraction of their transferrin receptors such that the growth-inhibiting antibody no longer binds, whereas another portion of their transferrin receptors is similar to those of the parental lines and binds both antibodies. These results argue that the antibody-selected mutant cell lines are heterozygous in transferrin receptor expression, probably with a mutation in one of the transferrin receptor structural genes. Images PMID:6092931

  1. Markers of Endothelial-to-Mesenchymal Transition: Evidence for Antibody-Endothelium Interaction during Antibody-Mediated Rejection in Kidney Recipients.

    PubMed

    Xu-Dubois, Yi-Chun; Peltier, Julie; Brocheriou, Isabelle; Suberbielle-Boissel, Caroline; Djamali, Arjang; Reese, Shannon; Mooney, Nuala; Keuylian, Zela; Lion, Julien; Ouali, Nacéra; Levy, Pierre P; Jouanneau, Chantal; Rondeau, Eric; Hertig, Alexandre

    2016-01-01

    Antibody-mediated rejection (ABMR) is a leading cause of allograft loss. Treatment efficacy depends on accurate diagnosis at an early stage. However, sensitive and reliable markers of antibody-endothelium interaction during ABMR are not available for routine use. Using immunohistochemistry, we retrospectively studied the diagnostic value of three markers of endothelial-to-mesenchymal transition (EndMT), fascin1, vimentin, and heat shock protein 47, for ABMR in 53 renal transplant biopsy specimens, including 20 ABMR specimens, 24 cell-mediated rejection specimens, and nine normal grafts. We validated our results in an independent set of 74 unselected biopsy specimens. Endothelial cells of the peritubular capillaries in grafts with ABMR expressed fascin1, vimentin, and heat shock protein 47 strongly, whereas those from normal renal grafts did not. The level of EndMT marker expression was significantly associated with current ABMR criteria, including capillaritis, glomerulitis, peritubular capillary C4d deposition, and donor-specific antibodies. These markers allowed us to identify C4d-negative ABMR and to predict late occurrence of disease. EndMT markers were more specific than capillaritis for the diagnosis and prognosis of ABMR and predicted late (up to 4 years after biopsy) renal graft dysfunction and proteinuria. In the independent set of 74 renal graft biopsy specimens, the EndMT markers for the diagnosis of ABMR had a sensitivity of 100% and a specificity of 85%. Fascin1 expression in peritubular capillaries was also induced in a rat model of ABMR. In conclusion, EndMT markers are a sensitive and reliable diagnostic tool for detecting endothelial activation during ABMR and predicting late loss of allograft function. PMID:25995444

  2. Human monoclonal antiphospholipid antibodies disrupt the annexin A5 anticoagulant crystal shield on phospholipid bilayers: evidence from atomic force microscopy and functional assay.

    PubMed

    Rand, Jacob H; Wu, Xiao-Xuan; Quinn, Anthony S; Chen, Pojen P; McCrae, Keith R; Bovill, Edwin G; Taatjes, Douglas J

    2003-09-01

    The antiphospholipid (aPL) syndrome is an autoimmune condition that is marked by recurrent pregnancy losses and/or systemic vascular thrombosis in patients who have antibodies against phospholipid/co-factor complexes. The mechanism(s) for pregnancy losses and thrombosis in this condition is (are) not known. Annexin A5 is a potent anticoagulant protein, expressed by placental trophoblasts and endothelial cells, that crystallizes over anionic phospholipids, shielding them from availability for coagulation reactions. We previously presented data supporting the hypothesis that aPL antibody-mediated disruption of the anticoagulant annexin A5 shield could be a thrombogenic mechanism in the aPL syndrome. However, this has remained a subject of controversy. We therefore used atomic force microscopy, a method previously used to study the crystallization of annexin A5, to image the effects of monoclonal human aPL antibodies on the crystal structure of the protein over phospholipid bilayers. In the presence of the aPL monoclonal antibodies (mAbs) and beta(2)-GPI, the major aPL co-factor, structures presumed to be aPL mAb-antigen complexes were associated with varying degrees of disruption to the annexin A5 crystallization pattern over the bilayer. In addition, measurements of prothrombinase activity on the phospholipid bilayers showed that the aPL mAbs reduced the anti-coagulant effect of annexin A5 and promoted thrombin generation. These data provide morphological evidence that support the hypothesis that aPL antibodies can disrupt annexin A5 binding to phospholipid membranes and permit increased generation of thrombin. The aPL antibody-mediated disruption of the annexin A5 anticoagulant shield may be an important prothrombotic mechanism in the aPL syndrome. PMID:12937161

  3. Humanization of predicted T-cell epitopes reduces the immunogenicity of chimeric antibodies: new evidence supporting a simple method.

    PubMed

    Roque-Navarro, Lourdes; Mateo, Cristina; Lombardero, Josefa; Mustelier, Geraudis; Fernández, Alicia; Sosa, Katya; Morrison, Sherrie L; Pérez, Rolando

    2003-08-01

    Genetic engineering has provided several approaches to reduce immunogenicity of murine antibodies. We described previously a new method based on the humanization of the linear epitopes presented to T cells. In brief, potential immunogenic epitopes in the variable region were identified and subjected to point mutations to make them human and/or to modify amphipatic motifs. The resulting recombinant antibody retained its antigen binding affinity and was less immunogenic in monkeys than their murine or chimeric predecessors are. The present study provides two new examples of this T-cell epitope humanization approach: ior-t1A murine monoclonal antibody (mMAb), which recognizes the human-CD6 molecule, and ior-C5 mMAb, which recognizes a novel glycoprotein expressed on the surface of malignant colorectal cells. Seven amino acids were substituted in ior-C5 and eleven residues in ior-t1A, by the corresponding residues from the highest homologous human sequences. Surprisingly, the homology between re-shaped chimeric antibody variable region frameworks and human sequences was 80-90%. Experiments in monkeys showed that T1AhT and C5hT "detopes" antibodies were less immunogenic than their chimeric analogues while they retained 30-50% of antigen binding affinities. The proposed method might be of general applicability to reduce immunogenicity of chimeric antibodies with therapeutic potential. PMID:14511570

  4. Evidence that Equine Rhinitis A Virus VP1 Is a Target of Neutralizing Antibodies and Participates Directly in Receptor Binding

    PubMed Central

    Warner, Simone; Hartley, Carol A.; Stevenson, Rachel A.; Ficorilli, Nino; Varrasso, Annalisa; Studdert, Michael J.; Crabb, Brendan S.

    2001-01-01

    Equine rhinitis A virus (ERAV) is a respiratory pathogen of horses and is classified as an Aphthovirus, the only non-Foot-and-mouth disease virus (FMDV) member of this genus. In FMDV, virion protein 1 (VP1) is a major target of protective antibodies and is responsible for viral attachment to permissive cells via an RGD motif located in a distal surface loop. Although both viruses share considerable sequence identity, ERAV VP1 does not contain an RGD motif. To investigate antibody and receptor-binding properties of ERAV VP1, we have expressed full-length ERAV VP1 in Escherichia coli as a glutathione S-transferase (GST) fusion protein (GST-VP1). GST-VP1 reacted specifically with antibodies present in serum from a rabbit immunized with purified ERAV virions and also in convalescent-phase sera from horses experimentally infected with ERAV. An antiserum raised in rabbits to GST-VP1 reacted strongly with viral VP1 and effectively neutralized ERAV infection in vitro. Using a flow cytometry-based binding assay, we found that GST-VP1, but not other GST fusion proteins, bound to cell surface receptors. This binding was reduced in a dose-dependent manner by the addition of purified ERAV virions, demonstrating the specificity of this interaction. A separate cell-binding assay also implicated GST-VP1 in receptor binding. Importantly, anti-GST-VP1 antibodies inhibited the binding of ERAV virions to Vero cells, suggesting that these antibodies exert their neutralizing effect by blocking viral attachment. Thus ERAV VP1, like its counterpart in FMDV, appears to be both a target of protective antibodies and involved directly in receptor binding. This study reveals the potential of recombinant VP1 molecules to serve as vaccines and diagnostic reagents for the control of ERAV infections. PMID:11533189

  5. Direct evidence for role of anti-saliva antibodies against salivary gland homogenate of P. argentipes in modulation of protective Th1-immune response against Leishmania donovani.

    PubMed

    Pushpanjali; Thakur, Ajit K; Purkait, Bidyut; Jamal, Fauzia; Singh, Manish K; Ahmed, Ghufran; Bimal, Sanjiva; Kumar, Vijay; Singh, Subhankar K; Keshri, Srikant; Das, Pradeep; Narayan, Shyam

    2016-10-01

    Currently the main concerns regarding control of visceral leishmaniasis (VL) caused by L. donovani are immunosuppression, relating toxicity of anti-leishmanial drug and little development in appropriate vaccine and vector (P. argentipes) control. Reports available from ex-vivo studies reflect significance of vector salivary gland homogenate (SGH) in reverting immunosuppression of infected VL subjects and as such the immunogenic nature of SGH can be a strategy to modulate immune system and anti-leishmanial function to enable immune response to control the disease. Several related studies also identified a better utility of vector anti-saliva antibodies in achieving such effects by an adoptive transfer approach instead of direct stimulation with SGH protein. However, conclusive evidences on VL cases are far beyond satisfactory to suggest role of SGH into modulation of host immune response in VL subjects in India. This study was under taken to make comparison on change in cytokines (TH1 and TH2) response pattern and anti-leishmanial macrophage (Mϕ) function following stimulation of their PBMCS with SGH protein derived from P. argentipes sand fly vector for VL or anti SGH antibodies raised in rabbit. This study reports for the first time that L. donovani sensitized healthy subject demonstrates an up-regulated Interferon-γ (TH1) and down regulate Interleukin-10 (TH2) production following stimulation of their PBMCs by P. argentipes anti-saliva antibodies accompanied with an improvement in anti-leishmanial Mϕ function for nitric oxide (NO) production. Subsequent experiments suggest that P. argentipes based anti-SGH antibodies when used to stimulate LD infected PBMCs in healthy subjects resulted in better clearance of Leishmania amastigotes load compare to SGH protein. Possibly the immunogenic components of anti-saliva an antibody maintains the level of protective cytokine (INF-γ) and seems to restrict the infection by host protection by vector saliva. PMID:27484246

  6. First molecular and biochemical analysis of in vivo affinity maturation in an ectothermic vertebrate

    PubMed Central

    Dooley, Helen; Stanfield, Robyn L.; Brady, Rebecca A.; Flajnik, Martin F.

    2006-01-01

    The cartilaginous fish are the oldest phylogenetic group in which Igs have been found. Sharks produce a unique Ig isotype, IgNAR, a heavy-chain homodimer that does not associate with light chains. Instead, the variable (V) regions of IgNAR bind antigen as soluble single domains. Our group has shown that IgNAR plays an integral part in the humoral response of nurse sharks (Ginglymostoma cirratum) upon antigen challenge. Here, we generated phage-displayed libraries of IgNAR V regions from an immunized animal and found a family of clones derived from the same rearrangement event but differentially mutated during expansion. Because of the cluster organization of shark Ig genes and the paucicopy nature of IgNAR, we were able to construct the putative ancestor of this family. By studying mutations in the context of clone affinities, we found evidence that affinity maturation occurs for this isotype. Subsequently, we were able to identify mutations important in the affinity improvement of this family. Because the family clones were all obtained after immunization, they provide insight into the in vivo maturation mechanisms, in general, and for single-domain antibody fragments. PMID:16446445

  7. Aggregation of Antibody Drug Conjugates at Room Temperature: SAXS and Light Scattering Evidence for Colloidal Instability of a Specific Subpopulation.

    PubMed

    Frka-Petesic, B; Zanchi, D; Martin, N; Carayon, S; Huille, S; Tribet, C

    2016-05-17

    Coupling a hydrophobic drug onto monoclonal antibodies via lysine residues is a common route to prepare antibody-drug conjugates (ADC), a promising class of biotherapeutics. But a few chemical modifications on protein surface often increase aggregation propensity, without a clear understanding of the aggregation mechanisms at stake (loss of colloidal stability, self-assemblies, denaturation, etc.), and the statistical nature of conjugation introduces polydispersity in the ADC population, which raises questions on whether the whole ADC population becomes unstable. To characterize the average interactions between ADC, we monitored small-angle X-ray scattering in solutions of monoclonal IgG1 human antibody drug conjugate, with average degree of conjugation of 0, 2, or 3 drug molecules per protein. To characterize stability, we studied the kinetics of aggregation at room temperature. The intrinsic Fuchs stability ratio of the ADC was estimated from the variation over time of scattered light intensity and hydrodynamic radius, in buffers of varying pH, and at diverse sucrose (0% or 10%) and NaCl (0 or 100 mM) concentrations. We show that stable ADC stock solutions became unstable upon pH shift, well below the pH of maximum average attraction between IgGs. Data indicate that aggregation can be ascribed to a fraction of ADC population usually representing less than 30 mol % of the sample. In contrast to the case of (monodisperse) monoclonal antibodies, our results suggest that a poor correlation between stability and average interaction parameters should be expected as a corollary of dispersity of ADC conjugation. In practice, the most unstable fraction of the ADC population can be removed by filtration, which affects remarkably the apparent stability of the samples. Finally, the lack of correlation between the kinetic stability and variations of the average inter-ADC interactions is tentatively attributed to the uneven nature of charge distributions and the presence of

  8. Serological Evidence of MERS-CoV Antibodies in Dromedary Camels (Camelus dromedaries) in Laikipia County, Kenya

    PubMed Central

    Deem, Sharon L.; Fèvre, Eric M.; Kinnaird, Margaret; Browne, A. Springer; Muloi, Dishon; Godeke, Gert-Jan; Koopmans, Marion; Reusken, Chantal B.

    2015-01-01

    Middle East respiratory syndrome coronavirus (MERS-CoV) is a recently identified virus causing severe viral respiratory illness in people. Little is known about the reservoir in the Horn of Africa. In Kenya, where no human MERS cases have been reported, our survey of 335 dromedary camels, representing nine herds in Laikipia County, showed a high seroprevalence (46.9%) to MERS-CoV antibodies. Between herd differences were present (14.3%– 82.9%), but was not related to management type or herd isolation. Further research should focus on identifying similarity between MERS-CoV viral isolates in Kenya and clinical isolates from the Middle East and elsewhere. PMID:26473733

  9. Immunoreactivity of anti-streptococcal monoclonal antibodies to human heart valves. Evidence for multiple cross-reactive epitopes.

    PubMed Central

    Gulizia, J. M.; Cunningham, M. W.; McManus, B. M.

    1991-01-01

    Association of group A streptococci with acute rheumatic fever and valvular heart disease is well established; however the basis of valve injury remains unclear. In this study, anti-streptococcal monoclonal antibodies (MAbs) cross-reactive with myocardium were reacted with sections from 22 rheumatic valves, nine normal, five endocarditic, one 'floppy,' and one Marfan valve. In immunohistochemical studies, MAb reactivity was observed with cardiac myocytes, smooth muscle cells, cell surface and cytoplasm of endothelial cells lining valves, and valvular interstitial cells. Endothelial basement membrane and elastin fibrils reacted with the MAbs, whereas collagen was unreactive. Similar reactivity was seen with sera from acute rheumatic fever patients. The anti-streptococcal MAbs reacted with intravalvular myosin and vimentin in Western blots, and purified elastin competitively inhibited the binding of the anti-streptococcal MAbs to whole group A streptococci. The data show that human heart valves have numerous sites of immunoreactivity with anti-streptococcal MAbs and acute rheumatic fever sera of potential importance in the pathogenesis of rheumatic valvular injury. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:1704188

  10. Conservation of arthropod midline netrin accumulation revealed with a cross-reactive antibody provides evidence for midline cell homology

    PubMed Central

    Simanton, Wendy; Clark, Stephanie; Clemons, Anthony; Jacowski, Caitlin; Farrell-VanZomeren, Adrienne; Beach, Paul; Browne, William E.; Duman-Scheel, Molly

    2009-01-01

    SUMMARY Although many similarities in arthropod CNS development exist, differences in axonogenesis and the formation of midline cells, which regulate axon growth, have been observed. For example, axon growth patterns in the ventral nerve cord of Artemia franciscana differ from that of Drosophila melanogaster. Despite such differences, conserved molecular marker expression at the midline of several arthropod species indicates that midline cells may be homologous in distantly related arthropods. However, data from additional species are needed to test this hypothesis. In this investigation, nerve cord formation and the putative homology of midline cells were examined in distantly related arthropods, including: long- and short-germ insects (D. melanogaster, Aedes aeygypti, and Tribolium castaneum), branchiopod crustaceans (A. franciscana and Triops longicauditus), and malacostracan crustaceans (Porcellio laevis and Parhyale hawaiensis). These comparative analyses were aided by a cross-reactive antibody generated against the Netrin (Net) protein, a midline cell marker and regulator of axonogenesis. The mechanism of nerve cord formation observed in Artemia is found in Triops, another branchiopod, but is not found in the other arthropods examined. Despite divergent mechanisms of midline cell formation and nerve cord development, Net accumulation is detected in a well-conserved subset of midline cells in branchiopod crustaceans, malacostracan crustaceans, and insects. Notably, the Net accumulation pattern is also conserved at the midline of the amphipod P. hawaiensis, which undergoes split germ-band development. Conserved Net accumulation patterns indicate that arthropod midline cells are homologous, and that Nets function to regulate commissure formation during CNS development of Tetraconata. PMID:19469853

  11. Human B cell activation. Evidence for diverse signals provided by various monoclonal anti-IgM antibodies

    PubMed Central

    1985-01-01

    Seven murine monoclonal antibodies (mAb) with different binding characteristics for human IgM varied markedly in their ability to induce proliferation of T cell-depleted human splenocytes. Two mAb (HB57 and 5D7) that bound to distinct epitopes on IgM were highly effective initiators of B cell proliferation at very low concentrations, in the presence of a T cell factor source. In the absence of T cell supernatant, both HB57 and 5D7 mAbs produced a markedly reduced degree of stimulation at all concentrations. Two additional anti-IgM mAb (VIIIE11 and Mu53) were distinctive in that, even at high concentrations, only limited proliferation was observed compared with the first group of mAb. This proliferation depended on the presence of T cell supernatant. Competitive-binding studies revealed that the epitope recognized by mAb Mu53 may be identical or very proximate to that recognized by HB57. Three other mAb (1G6, XG9, and P24) induced little or no proliferation. 1G6 bound to a unique epitope on the IgM molecule, whereas XG9 shared a determinant with VIIIE11 mAb. Regulatory influences of Fc receptor binding cannot account for all the diversity in proliferation observed with the individual anti-IgM mAb. Markedly augmented proliferation was obtained when B cells were cultured with certain combinations of anti-IgM mAb in the presence of exogenous T cell supernatant. The proliferation induced in the absence of T cell supernatant by high concentrations of mAb mixtures that included 1G6 approached that observed for the same mixtures in the presence of T cell supernatant. The data suggest that certain signals delivered through membrane IgM can bypass the need for T cell supernatant in the activation of human B lymphocytes. PMID:2413155

  12. Immunoglobulin G subclasses of fluorescent anti-Treponema pallidum antibodies: evidence for sequential development of specific anti-T. pallidum immunoglobulin G responses in patients with early syphilis.

    PubMed Central

    van der Sluis, J J; van Reede, E C; Boer, M

    1986-01-01

    The development of immunoglobulin G (IgG) subclass-specific anti-Treponema pallidum antibodies during the course of syphilis in humans was studied with sera from 50 untreated male patients. The patients were divided into five diagnosis groups. In the fluorescent treponemal antibody test, which delineates the presence of cross-reacting antibodies, as well as specific antitreponema antibodies, IgG1, IgG2, and IgG3 subclass antibodies were already present during the seronegative primary stage. Specific antibodies, which were detected by the fluorescent treponemal antibody absorption test, were first present during the serotype-variable primary stage. These antibodies were almost exclusively of the IgG1 and IgG3 subclasses. In later stages, antibodies of other subclasses were detectable. Titration of IgG1 antitreponema antibodies in three electrophoretically different IgG fractions revealed an asymmetric distribution in these fractions during primary syphilis. The antibodies were largely confined to the most basic fraction during primary syphilis. A sudden change in the distribution was noted between the end of the primary stage and the secondary stage; an even distribution of IgG1 antitreponema antibodies existed in the late latent stage. These findings confirm and extend previous results from our laboratory. The development of antibodies detected by both tests is discussed in terms of a sequential stimulation of the immune system due to the presence of an extracellular layer covering the treponemas or, alternatively, in terms of a suppression of the immune response during early syphilis. PMID:3531229

  13. Monoclonal Antibodies.

    ERIC Educational Resources Information Center

    Killington, R. A.; Powell, K. L.

    1984-01-01

    Monoclonal antibodies have provided an exciting addition to the "armory" of the molecular biologist and immunologist. This article discusses briefly the concept of, techniques available for, production of, and possible uses of monoclonal antibodies. (Author)

  14. Antimitochondrial antibody

    MedlinePlus

    ... antibodies (AMA) are substances ( antibodies ) that form against mitochondria. The mitochondria are an important part of cells. They are ... often, in people with other kinds of liver disease and some autoimmune diseases. Risks Risks for having ...

  15. Monoclonal Antibodies for Cancer Immunotherapy

    PubMed Central

    Weiner, Louis M.; Dhodapkar, Madhav V.; Ferrone, Soldano

    2008-01-01

    Monoclonal antibodies have emerged as effective therapeutic agents for many human malignancies. However, the ability of antibodies to initiate tumor antigen-specific immune responses has not received as much attention as other mechanisms of antibody action. Here we describe the rationale and evidence for developing anti-cancer antibodies that can stimulate host tumor antigen-specific immune responses. This may be accomplished by inducing antibody-dependent cellular cytotoxicity, by promoting antibody-targeted cross-presentation of tumor antigens or by triggering the idiotypic network. Future treatment modifications or combinations should be able to prolong, amplify and shape these immune responses to increase the clinical benefits of antibody therapy of human cancer. PMID:19304016

  16. Interleukin 6 dependence of anti-DNA antibody production: evidence for two pathways of autoantibody formation in pristane-induced lupus.

    PubMed

    Richards, H B; Satoh, M; Shaw, M; Libert, C; Poli, V; Reeves, W H

    1998-09-01

    Pristane induces a lupus-like syndrome in nonautoimmune mice characterized by the development of glomerulonephritis and lupus-associated autoantibodies. This is accompanied by overproduction of interleukin (IL)-6, a cytokine linked with autoimmune phenomena. The goal of this study was to evaluate the role of IL-6 in autoantibody production in pristane-induced lupus. BALB/cAn IL-6-deficient (-/-) and -intact (+/+) mice were treated with pristane or phosphate-buffered saline, and autoantibody production was evaluated. Pristane induced high levels of immunoglobulin (Ig)G anti-single-stranded DNA, -double-stranded (ds)DNA, and -chromatin antibodies in IL-6(+/+), but not IL-6(-/-) mice by enzyme-linked immunosorbent assay. High titer IgG anti-dsDNA antibodies also were detected in sera from +/+, but not -/-, mice by Crithidia luciliae kinetoplast staining. The onset of IgG anti-dsDNA antibody production in +/+ mice occurred >5 mo after pristane treatment, well after the onset of nephritis, suggesting that these antibodies are not directly responsible for inducing renal disease. In contrast to anti-DNA, the frequencies of anti-nRNP/Sm and anti-Su antibodies were similar in pristane-treated IL-6(-/-) and IL-6(+/+) mice. However, levels were higher in the +/+ group. These results suggest that IgG anti-DNA and chromatin antibodies in pristane-treated mice are strictly IL-6 dependent, whereas induction of anti-nRNP/Sm and Su autoantibodies is IL-6 independent. The IL-6 dependence of anti-DNA, but not anti-nRNP/Sm, may have implications for understanding the patterns of autoantibody production in lupus. Anti-DNA antibodies are produced transiently, mainly during periods of disease activity, whereas anti-nRNP/Sm antibody levels are relatively insensitive to disease activity. This may reflect the differential IL-6 dependence of the two responses. PMID:9730900

  17. Antithyroid microsomal antibody

    MedlinePlus

    Thyroid antimicrosomal antibody; Antimicrosomal antibody; Microsomal antibody; Thyroid peroxidase antibody; TPOAb ... test is done to confirm the cause of thyroid problems, including Hashimoto thyroiditis . The test is also ...

  18. Direct evidence that decreased serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in sickle cell disease is related to antibody deficiency.

    PubMed Central

    Bjornson, A B; Lobel, J S

    1987-01-01

    Two approaches were used to demonstrate that reduction in serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in children with sickle cell disease is related to a deficiency of antibodies to pneumococcal capsular polysaccharide. First, opsonization of S. pneumoniae mediated by the alternative pathway in patients' sera was restored to normal by addition of the purified IgG or IgM fraction of goat antiserum to capsular polysaccharide of the homologous serotype. Secondly, IgG antibody titers to capsular polysaccharide in patients' sera correlated significantly with alternative pathway-mediated opsonization; the correlation between titers of IgM anticapsular antibodies and opsonization approached statistical significance. The sum of the IgG and IgM anticapsular antibody titers correlated most significantly with opsonization. Our results suggest that reduction in alternative pathway-mediated opsonization in sera from children with sickle cell disease is related to low levels of both IgG and IgM anticapsular antibodies. Images PMID:3805275

  19. Direct evidence that decreased serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in sickle cell disease is related to antibody deficiency.

    PubMed

    Bjornson, A B; Lobel, J S

    1987-02-01

    Two approaches were used to demonstrate that reduction in serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in children with sickle cell disease is related to a deficiency of antibodies to pneumococcal capsular polysaccharide. First, opsonization of S. pneumoniae mediated by the alternative pathway in patients' sera was restored to normal by addition of the purified IgG or IgM fraction of goat antiserum to capsular polysaccharide of the homologous serotype. Secondly, IgG antibody titers to capsular polysaccharide in patients' sera correlated significantly with alternative pathway-mediated opsonization; the correlation between titers of IgM anticapsular antibodies and opsonization approached statistical significance. The sum of the IgG and IgM anticapsular antibody titers correlated most significantly with opsonization. Our results suggest that reduction in alternative pathway-mediated opsonization in sera from children with sickle cell disease is related to low levels of both IgG and IgM anticapsular antibodies. PMID:3805275

  20. Antithyroglobulin antibody

    MedlinePlus

    ... may be due to: Graves disease Hashimoto thyroiditis Hypothyroidism Systemic lupus erythematosus (SLE) Thyrotoxicosis Type 1 diabetes ... Antibody Chronic thyroiditis (Hashimoto disease) Graves disease Hyperthyroidism Hypothyroidism Systemic lupus erythematosus T3 test Update Date 5/ ...

  1. Evidence of a pro-apoptotic effect of specific antibodies in a bovine macrophage model of infection with Mycobacterium avium subsp. paratuberculosis.

    PubMed

    Jolly, Ana; Lompardía, Silvina; Hajos, Silvia E; Mundo, Silvia L

    2016-01-01

    Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's disease (JD), a chronic granulomatous enteritis in ruminants. Understanding the protective immune response following infection is crucial to improve the diagnosis and the development of vaccines against this disease. The goal of this work was to assess whether specific antibodies were able to modulate the macrophage response to MAP infection by evaluating apoptosis and TNF-α secretion in an in vitro model. Sera from healthy (n=2), MAP-infected (n=3) and lipoarabinomannan (LAM)-immunized (n=3) bovines were evaluated. LAM was chosen as immunogen due to its relevant role in mycobacterial pathogenesis. We demonstrated by two different techniques (Acridine Orange/Ethidium Bromide microscopy and Annexin V/7-Amino-Actinomycin D flow cytometry) that the immune sera from both, MAP-infected and LAM-immunized bovines, significantly increased macrophage apoptosis in infected cultures. Comparable levels of apoptosis were detected when MAP was pre-incubated with purified specific antibodies instead of whole serum. Furthermore, this effect was accompanied by a significantly higher secretion of TNF-α. These results strongly suggest that specific antibodies could limit the impact of MAP on the apoptosis of bovine cells. This work would contribute to elucidate the role of the specific antibody response in bovine JD and its prevention. PMID:26827838

  2. Natural antibody - Biochemistry and functions.

    PubMed

    Rahyab, Ali Seyar; Alam, Amit; Kapoor, Aricka; Zhang, Ming

    2011-01-01

    Natural antibodies have been common knowledge in the scientific community for more than half a century. Initially disregarded, their functions have garnered a newfound interest recently. Natural antibodies are usually polyreactive IgM antibodies and are implicated in numerous physiologic and pathologic processes. Current research demonstrates they play a role in adaptive and innate immune responses, autoimmunity, and apoptosis. Evidence exists that they are involved in the modulation of neurodegenerative disorders and malignancy. Furthermore, natural antibodies have been implicated in ischemia reperfusion injury and atherosclerosis. As such the study of natural antibodies may provide new insight into normal physiologic processes whilst concurrently paving the road for a wide-range of possible therapeutic options. PMID:25309852

  3. Bispecific antibodies.

    PubMed

    Kontermann, Roland E; Brinkmann, Ulrich

    2015-07-01

    Bispecific antibodies (bsAbs) combine specificities of two antibodies and simultaneously address different antigens or epitopes. BsAbs with 'two-target' functionality can interfere with multiple surface receptors or ligands associated, for example with cancer, proliferation or inflammatory processes. BsAbs can also place targets into close proximity, either to support protein complex formation on one cell, or to trigger contacts between cells. Examples of 'forced-connection' functionalities are bsAbs that support protein complexation in the clotting cascade, or tumor-targeted immune cell recruiters and/or activators. Following years of research and development (R&D), the first bsAb was approved in 2009. Another bsAb entered the market in December 2014 and several more are in clinical trials. Here, we describe the potentials of bsAbs to become the next wave of antibody-based therapies, focusing on molecules in clinical development. PMID:25728220

  4. A Mouse Model for Conditional Secretion of Specific Single-Chain Antibodies Provides Genetic Evidence for Regulation of Cortical Plasticity by a Non-cell Autonomous Homeoprotein Transcription Factor

    PubMed Central

    Bertini, Eva; Ribot, Jérôme; Di Nardo, Ariel A.; Volovitch, Michel; Prochiantz, Alain

    2016-01-01

    During postnatal life the cerebral cortex passes through critical periods of plasticity allowing its physiological adaptation to the environment. In the visual cortex, critical period onset and closure are influenced by the non-cell autonomous activity of the Otx2 homeoprotein transcription factor, which regulates the maturation of parvalbumin-expressing inhibitory interneurons (PV cells). In adult mice, the maintenance of a non-plastic adult state requires continuous Otx2 import by PV cells. An important source of extra-cortical Otx2 is the choroid plexus, which secretes Otx2 into the cerebrospinal fluid. Otx2 secretion and internalization requires two small peptidic domains that are part of the DNA-binding domain. Thus, mutating these “transfer” sequences also modifies cell autonomous transcription, precluding this approach to obtain a cell autonomous-only mouse. Here, we develop a mouse model with inducible secretion of an anti-Otx2 single-chain antibody to trap Otx2 in the extracellular milieu. Postnatal secretion of this single-chain antibody by PV cells delays PV maturation and reduces plasticity gene expression. Induced adult expression of this single-chain antibody in cerebrospinal fluid decreases Otx2 internalization by PV cells, strongly induces plasticity gene expression and reopens physiological plasticity. We provide the first mammalian genetic evidence for a signaling mechanism involving intercellular transfer of a homeoprotein transcription factor. Our single-chain antibody mouse model is a valid strategy for extracellular neutralization that could be applied to other homeoproteins and signaling molecules within and beyond the nervous system. PMID:27171438

  5. A Mouse Model for Conditional Secretion of Specific Single-Chain Antibodies Provides Genetic Evidence for Regulation of Cortical Plasticity by a Non-cell Autonomous Homeoprotein Transcription Factor.

    PubMed

    Bernard, Clémence; Vincent, Clémentine; Testa, Damien; Bertini, Eva; Ribot, Jérôme; Di Nardo, Ariel A; Volovitch, Michel; Prochiantz, Alain

    2016-05-01

    During postnatal life the cerebral cortex passes through critical periods of plasticity allowing its physiological adaptation to the environment. In the visual cortex, critical period onset and closure are influenced by the non-cell autonomous activity of the Otx2 homeoprotein transcription factor, which regulates the maturation of parvalbumin-expressing inhibitory interneurons (PV cells). In adult mice, the maintenance of a non-plastic adult state requires continuous Otx2 import by PV cells. An important source of extra-cortical Otx2 is the choroid plexus, which secretes Otx2 into the cerebrospinal fluid. Otx2 secretion and internalization requires two small peptidic domains that are part of the DNA-binding domain. Thus, mutating these "transfer" sequences also modifies cell autonomous transcription, precluding this approach to obtain a cell autonomous-only mouse. Here, we develop a mouse model with inducible secretion of an anti-Otx2 single-chain antibody to trap Otx2 in the extracellular milieu. Postnatal secretion of this single-chain antibody by PV cells delays PV maturation and reduces plasticity gene expression. Induced adult expression of this single-chain antibody in cerebrospinal fluid decreases Otx2 internalization by PV cells, strongly induces plasticity gene expression and reopens physiological plasticity. We provide the first mammalian genetic evidence for a signaling mechanism involving intercellular transfer of a homeoprotein transcription factor. Our single-chain antibody mouse model is a valid strategy for extracellular neutralization that could be applied to other homeoproteins and signaling molecules within and beyond the nervous system. PMID:27171438

  6. Antithyroid microsomal antibody

    MedlinePlus

    ... Thyroid antimicrosomal antibody; Antimicrosomal antibody; Microsomal antibody; Thyroid peroxidase antibody; TPOAb Images Blood test References Guber HA, Faraq AF. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds. Henry's Clinical ...

  7. Antibodies to cardiac receptors.

    PubMed

    Boivin-Jahns, V; Schlipp, A; Hartmann, S; Panjwani, P; Klingel, K; Lohse, M J; Ertl, G; Jahns, R

    2012-12-01

    Inflammation of cardiac tissue is generally associated with an activation of the host's immune system. On the one hand, this activation is mandatory to protect the heart by fighting the invading microbial agents or toxins and by engaging myocardial reparation and healing processes. On the other hand, uncontrolled activation of the immune defense has the risk of an arousal of auto- or cross-reactive immune cells, which in some cases bring more harm than good. Dependent on the individual genetic predisposition, such heart-directed autoimmune reactions most likely occur as a result of myocyte apoptosis or necrosis and subsequent liberation of self-antigens previously hidden to the immune system. During the past two decades, evidence for a pathogenic relevance of autoimmunity in human heart disease has substantially increased. Conformational cardiac (auto)antibodies affecting cardiac function and, in particular, (auto)antibodies that target G protein-coupled cardiac membrane receptors are thought to play a key role in the development of heart failure. Clinical pilot studies even suggest that such antibodies negatively affect survival in heart failure patients. However, the true prevalence and clinical impact of many cardiac (auto)antibodies in human heart diseases are still unclear, as are the events triggering their formation, their titer course, and their patterns of clearance and/or persistence. The present article summarizes current knowledge in the field of cardiac receptor (auto)antibodies including recent efforts to address some of the aforementioned gaps of knowledge, thereby attempting to pave the way for novel, more specific therapeutic approaches. PMID:23183584

  8. Evidence that antibodies against recombinant SnSAG1 of Sarcocystis neurona merozoites are involved in infection and immunity in equine protozoal myeloencephalitis.

    PubMed

    Ellison, Siobhan; Witonsky, Sharon

    2009-07-01

    Sarcocystis neurona is the principal etiologic agent of equine protozoal myeloencephalitis (EPM). An immunodominant protein of S. neurona, SnSAG-1, is expressed by the majority of S. neurona merozoites isolated from spinal tissues of horses diagnosed with EPM and may be a candidate for diagnostic tests and prophylaxis for EPM. Five horses were vaccinated with adjuvanted recombinant SnSAG1 (rSnSAG1) and 5 control (sham vaccinated) horses were vaccinated with adjuvant only. Serum was evaluated pre- and post-vaccination, prior to challenge, for antibodies against rSnSAG1 and inhibitory effects on the infectivity of S. neurona by an in vitro serum neutralization assay. The effect of vaccination with rSnSAG1 on in vivo infection by S. neurona was evaluated by challenging all the horses with S. neurona merozoites. Blinded daily examinations and 4 blinded neurological examinations were used to evaluate the presence of clinical signs of EPM. The 5 vaccinated horses developed serum and cerebrospinal fluid (CSF) titers of SnSAG1, detected by enzyme-linked immunosorbent assay (ELISA), post-vaccination. Post-vaccination serum from vaccinated horses was found to have an inhibitory effect on merozoites, demonstrated by in vitro bioassay. Following the challenge, the 5 control horses displayed clinical signs of EPM, including ataxia. While 4 of the 5 vaccinated horses did not become ataxic. One rSnSAG-1 vaccinated horse showed paresis in 1 limb with muscle atrophy. All horses showed mild, transient, cranial nerve deficits; however, disease did not progress to ataxia in rSnSAG-1 vaccinated horses. The study showed that vaccination with rSnSAG-1 produced antibodies in horses that neutralized merozoites when tested by in vitro culture and significantly reduced clinical signs demonstrated by in vivo challenge. PMID:19794889

  9. Antibody Engineering and Therapeutics

    PubMed Central

    Almagro, Juan Carlos; Gilliland, Gary L; Breden, Felix; Scott, Jamie K; Sok, Devin; Pauthner, Matthias; Reichert, Janice M; Helguera, Gustavo; Andrabi, Raiees; Mabry, Robert; Bléry, Mathieu; Voss, James E; Laurén, Juha; Abuqayyas, Lubna; Barghorn, Stefan; Ben-Jacob, Eshel; Crowe, James E; Huston, James S; Johnston, Stephen Albert; Krauland, Eric; Lund-Johansen, Fridtjof; Marasco, Wayne A; Parren, Paul WHI; Xu, Kai Y

    2014-01-01

    The 24th Antibody Engineering & Therapeutics meeting brought together a broad range of participants who were updated on the latest advances in antibody research and development. Organized by IBC Life Sciences, the gathering is the annual meeting of The Antibody Society, which serves as the scientific sponsor. Preconference workshops on 3D modeling and delineation of clonal lineages were featured, and the conference included sessions on a wide variety of topics relevant to researchers, including systems biology; antibody deep sequencing and repertoires; the effects of antibody gene variation and usage on antibody response; directed evolution; knowledge-based design; antibodies in a complex environment; polyreactive antibodies and polyspecificity; the interface between antibody therapy and cellular immunity in cancer; antibodies in cardiometabolic medicine; antibody pharmacokinetics, distribution and off-target toxicity; optimizing antibody formats for immunotherapy; polyclonals, oligoclonals and bispecifics; antibody discovery platforms; and antibody-drug conjugates. PMID:24589717

  10. Evidence of Dengue Virus Transmission and Factors Associated with the Presence of Anti-Dengue Virus Antibodies in Humans in Three Major Towns in Cameroon

    PubMed Central

    Demanou, Maurice; Pouillot, Régis; Grandadam, Marc; Boisier, Pascal; Kamgang, Basile; Hervé, Jean Pierre; Rogier, Christophe; Rousset, Dominique; Paupy, Christophe

    2014-01-01

    Background Dengue is not well documented in Africa. In Cameroon, data are scarce, but dengue infection has been confirmed in humans. We conducted a study to document risk factors associated with anti-dengue virus Immunoglobulin G seropositivity in humans in three major towns in Cameroon. Methodology/Principal Findings A cross sectional survey was conducted in Douala, Garoua and Yaounde, using a random cluster sampling design. Participants underwent a standardized interview and were blood sampled. Environmental and housing characteristics were recorded. Randomized houses were prospected to record all water containers, and immature stages of Aedes mosquitoes were collected. Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects. Anti-dengue IgG were found from 61.4% of sera in Douala (n = 699), 24.2% in Garoua (n = 728) and 9.8% in Yaounde (n = 603). IgM were found from 0.3% of Douala samples, 0.1% of Garoua samples and 0.0% of Yaounde samples. Seroneutralization on randomly selected IgG positive sera showed that 72% (n = 100) in Douala, 80% (n = 94) in Garoua and 77% (n = 66) in Yaounde had antibodies specific for dengue virus serotype 2 (DENV-2). Age, temporary house walls materials, having water-storage containers, old tires or toilets in the yard, having no TV, having no air conditioning and having travelled at least once outside the city were independently associated with anti-dengue IgG positivity in Douala. Age, having uncovered water containers, having no TV, not being born in Garoua and not breeding pigs were significant risk factors in Garoua. Recent history of malaria, having banana trees and stagnant water in the yard were independent risk factors in Yaounde. Conclusion/Significance In this survey, most identified risk factors of dengue were related to housing conditions. Poverty and underdevelopment are central to the dengue

  11. Patient-Derived Antibody Targets Tumor Cells

    Cancer.gov

    An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

  12. Monoclonal antibodies.

    PubMed

    2009-01-01

    The ability to produce and exploit monoclonal antibodies (mAbs) has revolutionized many areas of biological sciences. The unique property of an mAb is that it is a single species of immunoglobulin (IG) molecule. This means that the specificity of the interaction of the paratopes on the IG, with the epitopes on an antigenic target, is the same on every molecule. This property can be used to great benefit in immunoassays to provide tests of defined specificity and sensitivity, which improve the possibilities of standardization. The performance of assays can often be determined relating the actual weight of antibody (hence the number of molecules) to the activity. Often the production of an mAb against a specific epitope is the only way that biological entities can be differentiated. This chapter outlines the areas involving the development of assays based on mAbs. The problems involved address include the physical aspects of mAbs and how they may affect assay design and also the implications of results based on monospecific reagents. Often these are not fully understood, leading to assays that are less than satisfactory, which does not justify the relatively high cost of preparing and screening of mAbs. There are many textbooks and reviews dealing with the preparation of mAbs, the principles involved, and various purification and manipulative methods for the preparation of fragments and conjugation. There has been little general information attempting to summarize the best approaches to assay design using mAbs. Much time can be wasted through bad planning, and this is particularly relevant to mAbs. A proper understanding of some basic principles is essential. It is beyond the scope of this chapter to discuss all aspects, but major areas are highlighted. PMID:19219589

  13. Serum herpes simplex antibodies

    MedlinePlus

    ... gov/ency/article/003352.htm Serum herpes simplex antibodies To use the sharing features on this page, please enable JavaScript. Serum herpes simplex antibodies is a blood test that looks for antibodies ...

  14. Back to the future: recombinant polyclonal antibody therapeutics.

    PubMed

    Wang, Xian-Zhe; Coljee, Vincent W; Maynard, Jennifer A

    2013-11-01

    Antibody therapeutics are one of the fastest growing classes of pharmaceuticals, with an annual US market over $20 billion, developed to treat a variety of diseases including cancer, auto-immune and infectious diseases. Most are currently administered as a single molecule to treat a single disease, however there is mounting evidence that cocktails of multiple antibodies, each with a unique binding specificity and protective mechanism, may improve clinical efficacy. Here, we review progress in the development of oligoclonal combinations of antibodies to treat disease, focusing on identification of synergistic antibodies. We then discuss the application of modern antibody engineering technologies to produce highly potent antibody preparations, including oligoclonal antibody cocktails and truly recombinant polyclonal antibodies. Specific examples illustrating the synergy conferred by multiple antibodies will be provided for diseases caused by botulinum toxin, cancer and immune thrombocytopenia. The bioprocessing and regulatory options for these preparations will be discussed. PMID:24443710

  15. Back to the future: recombinant polyclonal antibody therapeutics

    PubMed Central

    Wang, Xian-zhe; Coljee, Vincent W.; Maynard, Jennifer A.

    2013-01-01

    Antibody therapeutics are one of the fastest growing classes of pharmaceuticals, with an annual US market over $20 billion, developed to treat a variety of diseases including cancer, auto-immune and infectious diseases. Most are currently administered as a single molecule to treat a single disease, however there is mounting evidence that cocktails of multiple antibodies, each with a unique binding specificity and protective mechanism, may improve clinical efficacy. Here, we review progress in the development of oligoclonal combinations of antibodies to treat disease, focusing on identification of synergistic antibodies. We then discuss the application of modern antibody engineering technologies to produce highly potent antibody preparations, including oligoclonal antibody cocktails and truly recombinant polyclonal antibodies. Specific examples illustrating the synergy conferred by multiple antibodies will be provided for diseases caused by botulinum toxin, cancer and immune thrombocytopenia. The bioprocessing and regulatory options for these preparations will be discussed. PMID:24443710

  16. Selection of antibodies from synthetic antibody libraries.

    PubMed

    Harel Inbar, Noa; Benhar, Itai

    2012-10-15

    More than 2 dozen years had passed since the field of antibody engineering was established, with the first reports of bacterial [1-3] and mammalian cells [4] expression of recombinant antibody fragments, and in that time a lot of effort was dedicated to the development of efficient technological means, intended to assist in the creation of therapeutic monoclonal antibodies (mAbs). Research focus was given to two intertwined technological aspects: the selection platform and the recombinant antibody repertoires. In accordance with these areas of interest, it is the goal of this chapter to describe the various selection tools and antibody libraries existing, with emphasis on the later, and their applications. This chapter gives a far from exhaustive, subjective "historic account" of the field, describing the selection platforms, the different formats of antibody repertoires and the applications of both for selecting recombinant antibodies. Several excellent books provide detailed protocols for constructing antibody libraries and selecting antibodies from those libraries [5-13]. Such books may guide a newcomer to the field in the fine details of antibody engineering. We would like to offer advice to the novice: although seemingly simple, effective library construction and antibody isolation provide best benefits in the hands of professionals. It is an art as much as it is science. PMID:22244834

  17. Humoral immune response of the small-spotted catshark, Scyliorhinus canicula.

    PubMed

    Crouch, Kathryn; Smith, Lauren E; Williams, Rebecca; Cao, Wei; Lee, Mike; Jensen, Allan; Dooley, Helen

    2013-05-01

    Cartilaginous fishes are the oldest group in which an adaptive immune system based on immunoglobulin-superfamily members is found. This manuscript compares humoral immune function in small-spotted catshark (Scyliorhinus canicula) with that described for spiny dogfish (Squalus acanthias), another member of the Squalomorphi superorder, and nurse shark, the model for humoral immunity in elasmobranchs and a member of the Galeomorphi superorder. Although small-spotted catshark and nurse shark are separated by over 200 million years we found that immunoglobulin isoforms are well conserved between the two species. However, the plasma protein profile of small-spotted catshark was most similar to that of spiny dogfish, with low levels of pentameric IgM, and IgNAR present as a multimer in plasma rather than a monomer. We show that an antigen-specific monomeric IgM response, with a profile similar to that described previously for nurse sharks, can be raised in small-spotted catshark. Lacking polyclonal or monoclonal antibody reagents for detecting catshark IgNAR we investigated phage-display and recombinant Fc-fusion protein expression as alternative methods to look for an antigen-specific response for this isotype. However, we could find no evidence of an antigen-specific IgNAR in the animals tested using either of these techniques. Thus, unlike nurse sharks where antigen-specific monomeric IgM and IgNAR appear together, it seems there may be a temporal or complete 'uncoupling' of these isotypes during a humoral response in the small-spotted catshark. PMID:23439398

  18. Antibodies and Selection of Monoclonal Antibodies.

    PubMed

    Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

    2016-01-01

    Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology. PMID:27236550

  19. Systems immunology: Beyond antibody titers.

    PubMed

    Cao, Raquel; Mejias, Asuncion; Ramilo, Octavio

    2016-07-01

    Despite the evident success of currently available vaccines to prevent infectious diseases, we still lack a full understanding of the mechanisms by which vaccines induce protective immune responses. Systems immunology applies multifaceted analytical tools to better understand the immune responses to vaccines by deep characterization of the cellular components, regulatory pathways, antibody responses and immune gene profiles with the ultimate goal of identifying the complex cellular, genetic and regulatory factors and mechanisms that contribute to effective and protective immune responses. PMID:27180310

  20. Antibody-Mediated Lung Transplant Rejection

    PubMed Central

    Hachem, Ramsey

    2012-01-01

    Antibody-mediated rejection after lung transplantation remains enigmatic. However, emerging evidence over the past several years suggests that humoral immunity plays an important role in allograft rejection. Indeed, the development of donor-specific antibodies after transplantation has been identified as an independent risk factor for acute cellular rejection and bronchiolitis obliterans syndrome. Furthermore, cases of acute antibody-mediated rejection resulting in severe allograft dysfunction have been reported, and these demonstrate that antibodies can directly injure the allograft. However, the incidence and toll of antibody-mediated rejection are unknown because there is no widely accepted definition and some cases may be unrecognized. Clearly, humoral immunity has become an important area for research and clinical investigation. PMID:23002428

  1. Novel Antibody Vectors for Imaging

    PubMed Central

    Olafsen, Tove; Wu, Anna M.

    2010-01-01

    Non-invasive molecular imaging approaches include nuclear, optical, MRI, CT, ultrasound and photoacoustic imaging, which require accumulation of a signal delivered by a probe at the target site. Monoclonal antibodies (mAbs) are high affinity molecules that can be used for specific, high signal delivery to cell surface molecules. However, their long circulation time in blood makes them unsuitable as imaging probes. Efforts to improve antibodies pharmacokinetics without compromising affinity and specificity have been made through protein engineering. Antibody variants that differ in antigen binding sites and size have been generated and evaluated as imaging probes to target tissues of interest. Fast clearing fragments such as single-chain Fv (scFv; 25 kDa) with one antigen binding site (monovalent) demonstrated low accumulation in tumors due the low exposure time to the target. Using scFv as building block to produce larger, bivalent fragments such as scFv dimers (diabodies, 50 kDa) and scFv-fusion proteins (80 kDa minibodies and 105 kDa scFv-Fc) resulted in higher tumor accumulation due to their longer residence time in blood. Imaging studies with these fragments following radiolabeling have demonstrated excellent, high contrast images in gamma cameras and PET scanners. Several studies have also investigated antibody fragments conjugated to fluorescence (near infrared dyes), bioluminescence (luciferases) and quantum dots for optical imaging and iron oxides nanoparticles for MRI. However, these studies indicate that there are several factors that influence successful targeting and imaging. These include stability of the antibody fragment, the labeling chemistry (direct or indirect), whether critical residues are modified, the number of antigen expressed on the cell, and whether the target has a rapid recycling rate or internalizes upon binding. The preclinical data presented are compelling and it is evident that antibody-based molecular imaging tracers will play an

  2. How to successfully patent therapeutic antibodies.

    PubMed

    Lahrtz, Fritz

    2015-04-01

    Therapeutic antibodies have become an established class of drugs for the treatment of a variety of diseases, especially cancer and autoimmune/inflammatory disorders, and a sufficient patent protection is a prerequisite for their successful commercialization. As monoclonal antibodies and their therapeutic potential have been well known for decades, the mere production of yet another therapeutic antibody is in many jurisdictions not considered a patentable invention. In contrast, antibodies with novel structural features and/or improved properties may be patentable. When drafting the claims, care should be taken to obtain a broad patent scope that protects both the antibody of interest and related antibodies having the same functional features, thereby preventing competitors from marketing a functionally equivalent antibody. Furthermore, the application should contain experimental evidence showing the improved properties of the claimed antibody. After the filing of a priority patent application, patent protection should be initiated at least in countries that are of particular commercial importance. Subsequent inventions relating to novel uses, formulations, dosage regimens, and combinations with other treatment modalities should be protected by further patent applications to extend patent term. PMID:25614506

  3. Antibodies and antibody-derived analytical biosensors

    PubMed Central

    Sharma, Shikha; Byrne, Hannah

    2016-01-01

    The rapid diagnosis of many diseases and timely initiation of appropriate treatment are critical determinants that promote optimal clinical outcomes and general public health. Biosensors are now being applied for rapid diagnostics due to their capacity for point-of-care use with minimum need for operator input. Antibody-based biosensors or immunosensors have revolutionized diagnostics for the detection of a plethora of analytes such as disease markers, food and environmental contaminants, biological warfare agents and illicit drugs. Antibodies are ideal biorecognition elements that provide sensors with high specificity and sensitivity. This review describes monoclonal and recombinant antibodies and different immobilization approaches crucial for antibody utilization in biosensors. Examples of applications of a variety of antibody-based sensor formats are also described. PMID:27365031

  4. Antibodies and antibody-derived analytical biosensors.

    PubMed

    Sharma, Shikha; Byrne, Hannah; O'Kennedy, Richard J

    2016-06-30

    The rapid diagnosis of many diseases and timely initiation of appropriate treatment are critical determinants that promote optimal clinical outcomes and general public health. Biosensors are now being applied for rapid diagnostics due to their capacity for point-of-care use with minimum need for operator input. Antibody-based biosensors or immunosensors have revolutionized diagnostics for the detection of a plethora of analytes such as disease markers, food and environmental contaminants, biological warfare agents and illicit drugs. Antibodies are ideal biorecognition elements that provide sensors with high specificity and sensitivity. This review describes monoclonal and recombinant antibodies and different immobilization approaches crucial for antibody utilization in biosensors. Examples of applications of a variety of antibody-based sensor formats are also described. PMID:27365031

  5. Lyme disease antibody

    MedlinePlus

    ... JavaScript. The Lyme disease blood test looks for antibodies in the blood to the bacteria that causes ... needed. A laboratory specialist looks for Lyme disease antibodies in the blood sample using the ELISA test . ...

  6. RBC Antibody Screen

    MedlinePlus

    ... be limited. Home Visit Global Sites Search Help? RBC Antibody Screen Share this page: Was this page ... Screen Related tests: Direct Antiglobulin Test ; Blood Typing ; RBC Antibody Identification ; Type and Screen; Crossmatch All content ...

  7. Antiparietal cell antibody test

    MedlinePlus

    ... Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; Vitamin B12 - anti- ... may use this test to help diagnose pernicious anemia. Pernicious anemia is a decrease in red blood ...

  8. Antibody Blood Tests

    MedlinePlus

    ... discovered that people with celiac disease who eat gluten have higher than normal levels of certain antibodies ... rye and barley that are generically known as “gluten.” Antibody Testing: Only A First Step To help ...

  9. Anti-acetylcholine receptor antibodies.

    PubMed Central

    Vincent, A; Newsom Davis, J

    1980-01-01

    Early suggestions that a humoral factor might be implicated in the disorder of neuromuscular transmission in myasthenia gravis have been confirmed by the detection of anti-AChR antibody in 85-90% of the patients with generalised disease and in 75% of cases with restricted ocular myasthenia. Plasma exchange reveals that serum anti-AChR usually has an inverse relationship to muscle strength and present evidence indicates that patients responding to thymectomy and immunosuppressive durg treatment usually show a consistent decline in serum anti-AChR titres. The antibody is heterogeneous and can lead to a loss of muscle AChR by several mechanisms. Anti-AChR is produced in the thymus in relatively small amounts. Anti-AChR antibody synthesis by thymic lymphocytes and pokeweed stimulated peripheral lymphocytes in culture provides a means of studying the effect of different lymphocyte populations in vitro. Analysis of clinical, immunological and HLA antigen characteristics in MG suggest that more than one mechanism may underlie the breakdown in tolerance to AChR, leading to the production of anti-AChR antibodies. PMID:7400823

  10. Modeling Antibody Diversity.

    ERIC Educational Resources Information Center

    Baker, William P.; Moore, Cathy Ronstadt

    1998-01-01

    Understanding antibody structure and function is difficult for many students. The rearrangement of constant and variable regions during antibody differentiation can be effectively simulated using a paper model. Describes a hands-on laboratory exercise which allows students to model antibody diversity using readily available resources. (PVD)

  11. Antibody Therapeutics in Oncology

    PubMed Central

    Wold, Erik D; Smider, Vaughn V; Felding, Brunhilde H

    2016-01-01

    One of the newer classes of targeted cancer therapeutics is monoclonal antibodies. Monoclonal antibody therapeutics are a successful and rapidly expanding drug class due to their high specificity, activity, favourable pharmacokinetics, and standardized manufacturing processes. Antibodies are capable of recruiting the immune system to attack cancer cells through complement-dependent cytotoxicity or antibody dependent cellular cytotoxicity. In an ideal scenario the initial tumor cell destruction induced by administration of a therapeutic antibody can result in uptake of tumor associated antigens by antigen-presenting cells, establishing a prolonged memory effect. Mechanisms of direct tumor cell killing by antibodies include antibody recognition of cell surface bound enzymes to neutralize enzyme activity and signaling, or induction of receptor agonist or antagonist activity. Both approaches result in cellular apoptosis. In another and very direct approach, antibodies are used to deliver drugs to target cells and cause cell death. Such antibody drug conjugates (ADCs) direct cytotoxic compounds to tumor cells, after selective binding to cell surface antigens, internalization, and intracellular drug release. Efficacy and safety of ADCs for cancer therapy has recently been greatly advanced based on innovative approaches for site-specific drug conjugation to the antibody structure. This technology enabled rational optimization of function and pharmacokinetics of the resulting conjugates, and is now beginning to yield therapeutics with defined, uniform molecular characteristics, and unprecedented promise to advance cancer treatment. PMID:27081677

  12. Engineering antibody therapeutics.

    PubMed

    Chiu, Mark L; Gilliland, Gary L

    2016-06-01

    The successful introduction of antibody-based protein therapeutics into the arsenal of treatments for patients has within a few decades fostered intense innovation in the production and engineering of antibodies. Reviewed here are the methods currently used to produce antibodies along with how our knowledge of the structural and functional characterization of immunoglobulins has resulted in the engineering of antibodies to produce protein therapeutics with unique properties, both biological and biophysical, that are leading to novel therapeutic approaches. Antibody engineering includes the introduction of the antibody combining site (variable regions) into a host of architectures including bi and multi-specific formats that further impact the therapeutic properties leading to further advantages and successes in patient treatment. PMID:27525816

  13. Therapeutic Recombinant Monoclonal Antibodies

    ERIC Educational Resources Information Center

    Bakhtiar, Ray

    2012-01-01

    During the last two decades, the rapid growth of biotechnology-derived techniques has led to a myriad of therapeutic recombinant monoclonal antibodies with significant clinical benefits. Recombinant monoclonal antibodies can be obtained from a number of natural sources such as animal cell cultures using recombinant DNA engineering. In contrast to…

  14. Recombinant renewable polyclonal antibodies

    PubMed Central

    Ferrara, Fortunato; D’Angelo, Sara; Gaiotto, Tiziano; Naranjo, Leslie; Tian, Hongzhao; Gräslund, Susanne; Dobrovetsky, Elena; Hraber, Peter; Lund-Johansen, Fridtjof; Saragozza, Silvia; Sblattero, Daniele; Kiss, Csaba; Bradbury, Andrew RM

    2015-01-01

    Only a small fraction of the antibodies in a traditional polyclonal antibody mixture recognize the target of interest, frequently resulting in undesirable polyreactivity. Here, we show that high-quality recombinant polyclonals, in which hundreds of different antibodies are all directed toward a target of interest, can be easily generated in vitro by combining phage and yeast display. We show that, unlike traditional polyclonals, which are limited resources, recombinant polyclonal antibodies can be amplified over one hundred million-fold without losing representation or functionality. Our protocol was tested on 9 different targets to demonstrate how the strategy allows the selective amplification of antibodies directed toward desirable target specific epitopes, such as those found in one protein but not a closely related one, and the elimination of antibodies recognizing common epitopes, without significant loss of diversity. These recombinant renewable polyclonal antibodies are usable in different assays, and can be generated in high throughput. This approach could potentially be used to develop highly specific recombinant renewable antibodies against all human gene products. PMID:25530082

  15. Expression of Recombinant Antibodies

    PubMed Central

    Frenzel, André; Hust, Michael; Schirrmann, Thomas

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines, and transgenic plants are promising to obtain antibodies with “human-like” post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications. PMID:23908655

  16. Antibodies as effectors.

    PubMed

    Corbeil, L B

    2002-09-10

    Antibodies are critical in protection against extracellular microbial pathogens. Although antibodies also play a role in transplant/tumor rejection and in autoimmune disease, this paper focuses on defense against bovine infections. Effector mechanisms of different bovine isotypes, subisotypes and allotypes are discussed. The importance of antigen specificity is also stressed. PMID:12072231

  17. Production Of Human Antibodies

    NASA Technical Reports Server (NTRS)

    Sammons, David W.; Neil, Garry A.

    1993-01-01

    Process for making human monoclonal antibodies based on combination of techniques. Antibodies made active against specific antigen. Process involves in vivo immunization of human B lymphocyte cells in mice. B cells of interest enriched in vitro before fusion. Method potentially applicable to any antigen. Does not rely on use of Epstein-Barr virus at any step. Human lymphocytes taken from any source.

  18. Affinity purification of antibodies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibodies are provided in a variety of formats that includes antiserum, hybridoma culture supernatant or ascites. They can all be used successfully in crude form for the detection of target antigens by immunoassay. However, it is advantageous to use purified antibody in defined quantity to facil...

  19. Antibodies in Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The expression of antibodies in plants has several promising applications that are currently being developed. Plants are being considered for the large scale production of antibodies needed for medical purposes. The benefit of using plants is that they are able to perform post-translational modifi...

  20. Anti Transglutaminase Antibodies Cause Ataxia in Mice

    PubMed Central

    Boscolo, Sabrina; Lorenzon, Andrea; Sblattero, Daniele; Florian, Fiorella; Stebel, Marco; Marzari, Roberto; Not, Tarcisio; Aeschlimann, Daniel; Ventura, Alessandro; Hadjivassiliou, Marios; Tongiorgi, Enrico

    2010-01-01

    Background Celiac disease (CD) is an autoimmune gastrointestinal disorder characterized by the presence of anti-transglutaminase 2 (TG2) and anti-gliadin antibodies. Amongst the neurological dysfunctions associated with CD, ataxia represents the most common one. Methods We analyzed by immunohistochemistry, the anti-neural reactivity of the serum from 20 CD patients. To determine the role of anti-TG2 antibodies in ataxia, two anti-TG2 single chain variable fragments (scFv), isolated from a phage-display IgA antibody library, were characterized by immunohistochemistry and ELISA, and injected in mice to study their effects on motor coordination. We found that 75% of the CD patient population without evidence of neurological involvement, has circulating anti-neural IgA and/or IgG antibodies. Two anti-TG2 scFvs, cloned from one CD patient, stained blood vessels but only one reacted with neurons. This anti-TG2 antibody showed cross reactivity with the transglutaminase isozymes TG3 and TG6. Intraventricular injection of the anti-TG2 or the anti-TG2/3/6 cross-reactive scFv provoked transient, equally intensive ataxia in mice. Conclusion The serum from CD patients contains anti-TG2, TG3 and TG6 antibodies that may potentially cause ataxia. PMID:20300628

  1. [Recombinant antibodies against bioweapons].

    PubMed

    Thullier, Philippe; Pelat, Thibaut; Vidal, Dominique

    2009-12-01

    The threat posed by bioweapons (BW) could lead to the re-emergence of such deadly diseases as plague or smallpox, now eradicated from industrialized countries. The development of recombinant antibodies allows tackling this risk because these recombinant molecules are generally well tolerated in human medicine, may be utilized for prophylaxis and treatment, and because antibodies neutralize many BW. Recombinant antibodies neutralizing the lethal toxin of anthrax, botulinum toxins and the smallpox virus have in particular been isolated recently, with different technologies. Our approach, which uses phage-displayed immune libraries built from non-human primates (M. fascicularis) to obtain recombinant antibodies, which may later be super-humanized (germlinized), has allowed us to obtain such BWs-neutralizing antibodies. PMID:20035695

  2. [Antiphospholipid antibodies in practice].

    PubMed

    Miyara, M; Diemert, M-C; Amoura, Z; Musset, L

    2012-04-01

    Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by the occurrence of thrombotic or obstetrical events associated with the presence in the serum of patients of antibodies that are associated with thrombosis. For the diagnosis of APS, the presence of either lupus anticoagulant, anticardiolipin or anti-β2-glycoprotein1 antibodies of IgG or IgM isotype is required through laboratory testing. Other autoantibodies such as antiphosphatidylethanolamin or antiphosphatidylserin/prothrombin complex antibodies may be interesting in the diagnosis of APS when common antiphospholipid antibodies are missing. These autoantibodies are still under evaluation for their diagnostic contribution. Despite numerous attempts, the assays that are available for the identification of antiphospholipid antibodies have not been standardized yet, which leads to high variability between reagents and laboratories. Thus, to optimize the biological monitoring of APS syndromes, it is mandatory to have consecutive samples analyzed in the same laboratory. PMID:22100197

  3. Affinity Purification of Antibodies.

    PubMed

    Hnasko, Robert M; McGarvey, Jeffery A

    2015-01-01

    Antibodies are provided in a variety of formats that include antiserum, hybridoma culture supernatant, or ascites. They can all be used successfully in crude form for the detection of target antigens by immunoassay. However, it is advantageous to use purified antibody in defined quantity to facilitate assay reproducibility, economy, and reduced interference of nonspecific components as well as improved storage, stability, and bio-conjugation. Although not always necessary, the relative simplicity of antibody purification using commercially available protein-A, protein-G, or protein-L resins with basic chromatographic principles warrants purification when antibody source material is available in sufficient quantity. Here, we define three simple methods using immobilized (1) protein-A, (2) protein-G, and (3) protein-L agarose beads to yield highly purified antibody. PMID:26160561

  4. Selection of Recombinant Human Antibodies.

    PubMed

    Tomszak, Florian; Weber, Susanne; Zantow, Jonas; Schirrmann, Thomas; Hust, Michael; Frenzel, André

    2016-01-01

    Since the development of therapeutic antibodies the demand of recombinant human antibodies is steadily increasing. Traditionally, therapeutic antibodies were generated by immunization of rat or mice, the generation of hybridoma clones, cloning of the antibody genes and subsequent humanization and engineering of the lead candidates. In the last few years, techniques were developed that use transgenic animals with a human antibody gene repertoire. Here, modern recombinant DNA technologies can be combined with well established immunization and hybridoma technologies to generate already affinity maturated human antibodies. An alternative are in vitro technologies which enabled the generation of fully human antibodies from antibody gene libraries that even exceed the human antibody repertoire. Specific antibodies can be isolated from these libraries in a very short time and therefore reduce the development time of an antibody drug at a very early stage.In this review, we describe different technologies that are currently used for the in vitro and in vivo generation of human antibodies. PMID:27236551

  5. The INNs and outs of antibody nonproprietary names.

    PubMed

    Jones, Tim D; Carter, Paul J; Plückthun, Andreas; Vásquez, Max; Holgate, Robert G E; Hötzel, Isidro; Popplewell, Andrew G; Parren, Paul W H I; Enzelberger, Markus; Rademaker, Hendrik J; Clark, Michael R; Lowe, David C; Dahiyat, Bassil I; Smith, Victoria; Lambert, John M; Wu, Herren; Reilly, Mary; Haurum, John S; Dübel, Stefan; Huston, James S; Schirrmann, Thomas; Janssen, Richard A J; Steegmaier, Martin; Gross, Jane A; Bradbury, Andrew R M; Burton, Dennis R; Dimitrov, Dimiter S; Chester, Kerry A; Glennie, Martin J; Davies, Julian; Walker, Adam; Martin, Steve; McCafferty, John; Baker, Matthew P

    2016-01-01

    An important step in drug development is the assignment of an International Nonproprietary Name (INN) by the World Health Organization (WHO) that provides healthcare professionals with a unique and universally available designated name to identify each pharmaceutical substance. Monoclonal antibody INNs comprise a -mab suffix preceded by a substem indicating the antibody type, e.g., chimeric (-xi-), humanized (-zu-), or human (-u-). The WHO publishes INN definitions that specify how new monoclonal antibody therapeutics are categorized and adapts the definitions to new technologies. However, rapid progress in antibody technologies has blurred the boundaries between existing antibody categories and created a burgeoning array of new antibody formats. Thus, revising the INN system for antibodies is akin to aiming for a rapidly moving target. The WHO recently revised INN definitions for antibodies now to be based on amino acid sequence identity. These new definitions, however, are critically flawed as they are ambiguous and go against decades of scientific literature. A key concern is the imposition of an arbitrary threshold for identity against human germline antibody variable region sequences. This leads to inconsistent classification of somatically mutated human antibodies, humanized antibodies as well as antibodies derived from semi-synthetic/synthetic libraries and transgenic animals. Such sequence-based classification implies clear functional distinction between categories (e.g., immunogenicity). However, there is no scientific evidence to support this. Dialog between the WHO INN Expert Group and key stakeholders is needed to develop a new INN system for antibodies and to avoid confusion and miscommunication between researchers and clinicians prescribing antibodies. PMID:26716992

  6. The INNs and outs of antibody nonproprietary names

    PubMed Central

    Jones, Tim D.; Carter, Paul J.; Plückthun, Andreas; Vásquez, Max; Holgate, Robert G.E.; Hötzel, Isidro; Popplewell, Andrew G.; Parren, Paul W.H.I.; Enzelberger, Markus; Rademaker, Hendrik J.; Clark, Michael R.; Lowe, David C.; Dahiyat, Bassil I.; Smith, Victoria; Lambert, John M.; Wu, Herren; Reilly, Mary; Haurum, John S.; Dübel, Stefan; Huston, James S.; Schirrmann, Thomas; Janssen, Richard A.J.; Steegmaier, Martin; Gross, Jane A.; Bradbury, Andrew R.M.; Burton, Dennis R.; Dimitrov, Dimiter S.; Chester, Kerry A.; Glennie, Martin J.; Davies, Julian; Walker, Adam; Martin, Steve; McCafferty, John; Baker, Matthew P.

    2016-01-01

    An important step in drug development is the assignment of an International Nonproprietary Name (INN) by the World Health Organization (WHO) that provides healthcare professionals with a unique and universally available designated name to identify each pharmaceutical substance. Monoclonal antibody INNs comprise a –mab suffix preceded by a substem indicating the antibody type, e.g., chimeric (-xi-), humanized (-zu-), or human (-u-). The WHO publishes INN definitions that specify how new monoclonal antibody therapeutics are categorized and adapts the definitions to new technologies. However, rapid progress in antibody technologies has blurred the boundaries between existing antibody categories and created a burgeoning array of new antibody formats. Thus, revising the INN system for antibodies is akin to aiming for a rapidly moving target. The WHO recently revised INN definitions for antibodies now to be based on amino acid sequence identity. These new definitions, however, are critically flawed as they are ambiguous and go against decades of scientific literature. A key concern is the imposition of an arbitrary threshold for identity against human germline antibody variable region sequences. This leads to inconsistent classification of somatically mutated human antibodies, humanized antibodies as well as antibodies derived from semi-synthetic/synthetic libraries and transgenic animals. Such sequence-based classification implies clear functional distinction between categories (e.g., immunogenicity). However, there is no scientific evidence to support this. Dialog between the WHO INN Expert Group and key stakeholders is needed to develop a new INN system for antibodies and to avoid confusion and miscommunication between researchers and clinicians prescribing antibodies. PMID:26716992

  7. NMDA receptor antibodies

    PubMed Central

    Ramberger, Melanie; Bsteh, Gabriel; Schanda, Kathrin; Höftberger, Romana; Rostásy, Kevin; Baumann, Matthias; Aboulenein-Djamshidian, Fahmy; Lutterotti, Andreas; Deisenhammer, Florian; Berger, Thomas

    2015-01-01

    Objectives: To analyze the frequency of NMDA receptor (NMDAR) antibodies in patients with various inflammatory demyelinating diseases of the CNS and to determine their clinical correlates. Methods: Retrospective case-control study from 2005 to 2014 with the detection of serum IgG antibodies to NMDAR, aquaporin-4, and myelin oligodendrocyte glycoprotein by recombinant live cell-based immunofluorescence assays. Fifty-one patients with acute disseminated encephalomyelitis, 41 with neuromyelitis optica spectrum disorders, 34 with clinically isolated syndrome, and 89 with multiple sclerosis (MS) were included. Due to a known association of NMDAR antibodies with seizures and behavioral symptoms, patients with those clinical manifestations were preferentially included and are therefore overrepresented in our cohort. Nine patients with NMDAR encephalitis, 94 patients with other neurologic diseases, and 48 healthy individuals were used as controls. Results: NMDAR antibodies were found in all 9 patients with NMDAR encephalitis but in only 1 of 215 (0.5%) patients with inflammatory demyelination and in none of the controls. This patient had relapsing-remitting MS with NMDAR antibodies present at disease onset, with an increase in NMDAR antibody titer with the onset of psychiatric symptoms and cognitive deficits. Conclusion: In demyelinating disorders, NMDAR antibodies are uncommon, even in those with symptoms seen in NMDAR encephalitis. PMID:26309901

  8. Monoclonal antibody "gold rush".

    PubMed

    Maggon, Krishan

    2007-01-01

    The market, sales and regulatory approval of new human medicines, during the past few years, indicates increasing number and share of new biologics and emergence of new multibillion dollar molecules. The global sale of monoclonal antibodies in 2006 were $20.6 billion. Remicade had annual sales gain of $1 billion during the past 3 years and five brands had similar increase in 2006. Rituxan with 2006 sales of $4.7 billion was the best selling monoclonal antibody and biological product and the 6th among the top selling medicinal brand. It may be the first biologic and monoclonal antibody to reach $10 billion annual sales in the near future. The strong demand from cancer and arthritis patients has surpassed almost all commercial market research reports and sales forecast. Seven monoclonal antibody brands in 2006 had sales exceeding $1 billion. Humanized or fully human monoclonal antibodies with low immunogenicity, enhanced antigen binding and reduced cellular toxicity provide better clinical efficacy. The higher technical and clinical success rate, overcoming of technical hurdles in large scale manufacturing, low cost of market entry and IND filing, use of fully human and humanized monoclonal antibodies has attracted funds and resources towards R&D. Review of industry research pipeline and sales data during the past 3 years indicate a real paradigm shift in industrial R&D from pharmaceutical to biologics and monoclonal antibodies. The antibody bandwagon has been joined by 200 companies with hundreds of new projects and targets and has attracted billions of dollars in R&D investment, acquisitions and licensing deals leading to the current Monoclonal Antibody Gold Rush. PMID:17691940

  9. Heart antibodies in cardiomyopathies.

    PubMed Central

    Trueman, T; Thompson, R A; Cummins, P; Littler, W A

    1981-01-01

    The reported frequency of circulating heart reactive antibodies in cardiomyopathies has varied and their significance is unknown. In this study such antibodies were sought in patients with primary congestive and hypertrophic cardiomyopathies and other heart diseases. Standard "single sandwich" and the more sensitive "double sandwich" indirect immunofluorescence techniques failed to disclose a significant difference between any cardiomyopathic group and controls in repeated experiments. With both techniques results were subject to considerable method-specific artefacts and observer variation. No published work associating heart antibodies detected by immunofluorescence methods with cariomyopathies adequately takes these into account. PMID:7028058

  10. HIV Antibody Test

    MedlinePlus

    ... despite the fact that the person is infected ( false negative ). If an HIV antibody test is negative ... infection (around 28 days) and may give a false-negative result. ^ Back to top Is there anything ...

  11. Platelet associated antibodies

    MedlinePlus

    ... of the following: For unknown reasons (idiopathic thrombocytopenic purpura, or ITP ) Side effect of certain drugs such ... 2012:chap 134. Read More Antibody Idiopathic thrombocytopenic purpura (ITP) Platelet count Serum globulin electrophoresis Thrombocytopenia Update ...

  12. Anti-sulfotyrosine antibodies

    DOEpatents

    Bertozzi, Carolyn R.; Kehoe, John; Bradbury, Andrew M.

    2009-09-15

    The invention provides anti-sulfotyrosine specific antibodies capable of detecting and isolating polypeptides that are tyrosine-sulfated. The sulfotyrosine antibodies and antibody fragments of the invention may be used to discriminate between the non-sulfated and sulfated forms of such proteins, using any number of immunological assays, such ELISAs, immunoblots, Western Blots, immunoprecipitations, and the like. Using a phage-display system, single chain antibodies (scFvs) were generated and screened against tyrosine-sulfated synthetic peptide antigens, resulting in the isolation of scFvs that specifically recognize sulfotyrosine-containing peptides and/or demonstrate sulfotyrosine-specific binding in tyrosine sulfated proteins. The VH and VL genes from one such sulfotyrosine-specific scFv were employed to generate a full length, sulfotyrosine-specific immunoglobulin.

  13. Monoclonal antibodies and cancer therapy

    SciTech Connect

    Reisfeld, R.A.; Sell, S.

    1985-01-01

    These proceedings collect papers on the subject of monoclonal antibodies. Topics include: Monoclonal antibody, biochemical effects and cancer therapeutic potential of tunicamycin, use of monoclonal antibodies for detection of lymph node metastases, active specific immunotherapy, and applications of monoclonal antibodies to investigations of growth factors.

  14. Infection of CD4{sup +} T lymphocytes by the human T cell leukemia virus type 1 is mediated by the glucose transporter GLUT-1: Evidence using antibodies specific to the receptor's large extracellular domain

    SciTech Connect

    Jin, Qingwen; Agrawal, Lokesh; VanHorn-Ali, Zainab; Alkhatib, Ghalib . E-mail: galkhati@iupui.edu

    2006-05-25

    To analyze HTLV-1 cytotropism, we developed a highly sensitive vaccinia virus-based assay measuring activation of a reporter gene upon fusion of two distinct cell populations. We used this system in a functional cDNA screening to isolate and confirm that the glucose transporter protein 1 (GLUT-1) is a receptor for HTLV-1. GLUT-1 is a ubiquitously expressed plasma membrane glycoprotein with 12 transmembrane domains and 6 extracellular loops (ECL). We demonstrate for the first time that peptide antibodies (GLUT-IgY) raised in chicken to the large extracellular loop (ECL1) detect GLUT-1 at the cell surface and inhibit envelope (Env)-mediated fusion and infection. Efficient GLUT-IgY staining was detected with peripheral blood CD4{sup +} lymphocytes purified by positive selection. Further, GLUT-IgY caused efficient inhibition of Env-mediated fusion and infection of CD4{sup +} T and significantly lower inhibition of CD8{sup +} T lymphocytes. The specificity of GLUT-IgY antibodies to GLUT-1 was demonstrated by ECL1 peptide competition studies. Grafting ECL1 of GLUT-1 onto the receptor-negative GLUT-3 conferred significant receptor activity. In contrast, grafting ECL1 of GLUT-3 onto GLUT-1 resulted in a significant loss of the receptor activity. The ECL1-mediated receptor activity was efficiently blocked with four different human monoclonal antibody (HMab) to HTLV-1 Env. The ECL1-derived peptide blocked HTLV-1 Env-mediated fusion with several nonhuman mammalian cell lines. The results demonstrate the utilization of cell surface GLUT-1 in HTLV-1 infection of CD4{sup +} T lymphocytes and implicate a critical role for the ECL1 region in viral tropism.

  15. Neuronal Surface Antibody-Mediated Autoimmune Encephalitis

    PubMed Central

    Linnoila, Jenny J.; Rosenfeld, Myrna R.; Dalmau, Josep

    2016-01-01

    In the past few years, many autoimmune encephalitides have been identified, with specific clinical syndromes and associated antibodies against neuronal surface antigens. There is compelling evidence that many of these antibodies are pathogenic and most of these encephalitides are highly responsive to immunotherapies. The clinical spectra of some of these antibody-mediated syndromes, especially those reported in only a few patients, are evolving. Others, such as anti-N-methyl-D-aspartate (NMDA) receptor encephalitis, are well characterized. Diagnosis involves recognizing the specific syndromes and identifying the antibody in a patient’s cerebrospinal fluid (CSF) and/or serum. These syndromes are associated with variable abnormalities in CSF, magnetic resonance imaging, and electroencephalography. Treatment is often multidisciplinary and should be focused upon neutralizing the effects of antibodies and eliminating their source. Overlapping disorders have been noted, with some patients having more than one neurologic autoimmune disease. In other patients, viral infections such as herpes simplex virus encephalitis trigger robust antineuronal autoimmune responses. PMID:25369441

  16. Viral antibody dynamics in a chiropteran host.

    PubMed

    Baker, Kate S; Suu-Ire, Richard; Barr, Jennifer; Hayman, David T S; Broder, Christopher C; Horton, Daniel L; Durrant, Christopher; Murcia, Pablo R; Cunningham, Andrew A; Wood, James L N

    2014-03-01

    Bats host many viruses that are significant for human and domestic animal health, but the dynamics of these infections in their natural reservoir hosts remain poorly elucidated. In these, and other, systems, there is evidence that seasonal life-cycle events drive infection dynamics, directly impacting the risk of exposure to spillover hosts. Understanding these dynamics improves our ability to predict zoonotic spillover from the reservoir hosts. To this end, we followed henipavirus antibody levels of >100 individual E. helvum in a closed, captive, breeding population over a 30-month period, using a powerful novel antibody quantitation method. We demonstrate the presence of maternal antibodies in this system and accurately determine their longevity. We also present evidence of population-level persistence of viral infection and demonstrate periods of increased horizontal virus transmission associated with the pregnancy/lactation period. The novel findings of infection persistence and the effect of pregnancy on viral transmission, as well as an accurate quantitation of chiropteran maternal antiviral antibody half-life, provide fundamental baseline data for the continued study of viral infections in these important reservoir hosts. PMID:24111634

  17. Pre-existing Antibody: Biotherapeutic Modality-Based Review.

    PubMed

    Gorovits, Boris; Clements-Egan, Adrienne; Birchler, Mary; Liang, Meina; Myler, Heather; Peng, Kun; Purushothama, Shobha; Rajadhyaksha, Manoj; Salazar-Fontana, Laura; Sung, Crystal; Xue, Li

    2016-03-01

    Pre-existing antibodies to biotherapeutic drugs have been detected in drug-naïve subjects for a variety of biotherapeutic modalities. Pre-existing antibodies are immunoglobulins that are either specific or cross-reacting with a protein or glycan epitopes on a biotherapeutic compound. Although the exact cause for pre-existing antibodies is often unknown, environmental exposures to non-human proteins, glycans, and structurally similar products are frequently proposed as factors. Clinical consequences of the pre-existing antibodies vary from an adverse effect on patient safety to no impact at all and remain highly dependent on the biotherapeutic drug modality and therapeutic indication. As such, pre-existing antibodies are viewed as an immunogenicity risk factor requiring a careful evaluation. Herein, the relationships between biotherapeutic modalities to the nature, prevalence, and clinical consequences of pre-existing antibodies are reviewed. Initial evidence for pre-existing antibody is often identified during anti-drug antibody (ADA) assay development. Other interfering factors known to cause false ADA positive signal, including circulating multimeric drug target, rheumatoid factors, and heterophilic antibodies, are discussed. PMID:26821802

  18. Antinuclear antibodies in mice

    PubMed Central

    Teague, P. O.; Friou, G. J.

    1969-01-01

    Seven-week-old and 16-week-old A/Jax mice were injected with viable spleen cells or homogenates of spleen cells obtained from older syngeneic mice which either had autoimmune anti-deoxyribonucleoprotein (DNP) antibody in their sera or lacked this activity. None of the 7-week-old recipients developed detectable anti-DNP antibody. However, most of the animals in the 16-week-old group developed this autoantibody. The viability of the cells and the presence of or absence of anti-DNP antibody in the donor's sera did not appear to influence the autoimmune response of these recipients. When viable thymus cells which were obtained from young A/Jax mice were transferred to groups of older syngeneic animals that had developed anti-DNP antibody spontaneously, the anti-DNP decreased or disappeared from the sera of most recipients. Untreated controls did not show this variation. When 36-week-old A/Jax mice which lacked anti-DNP antibody were injected with thymus or spleen cells obtained from young donors, none of the recipients or untreated controls developed anti-DNP antibody. After specific immunization with DNP, however, the control animals began to produce autoimmune anti-DNP antibody while the animals treated with thymus or spleen cells remained unresponsive. These observations support the hypothesis that in A/Jax mice: (1) autoimmunity to DNP may result from failure of normal homeostasis mechanisms which allow proliferation of autoimmune cells; (2) the number of cells with autoimmune potential may increase during ageing; (3) the efficiency of the homeostasis system may decrease during ageing as the result of microbial or genetic factors; and (4) cells which participate in homeostasis are found in the thymus and spleen of young mice and may be the thymus dependent lymphocytes. PMID:5307745

  19. Dissecting Epigenetic Dysregulation of Primary Antibody Deficiencies.

    PubMed

    Rodríguez-Cortez, Virginia C; Del Pino-Molina, Lucia; Rodríguez-Ubreva, Javier; López-Granados, Eduardo; Ballestar, Esteban

    2016-05-01

    Primary antibody deficiencies (PADs), the most prevalent inherited primary immunodeficiencies (PIDs), are associated with a wide range of genetic alterations (both monogenic or polygenic) in B cell-specific genes. However, correlations between the genotype and clinical manifestations are not evident in all cases indicating that genetic interactions, environmental and epigenetic factors may have a role in PAD pathogenesis. The recent identification of key defects in DNA methylation in common variable immunodeficiency as well as the multiple evidences on the role of epigenetic control during B cell differentiation, activation and during antibody formation highlight the importance of investing research efforts in dissecting the participation of epigenetic defects in this group of diseases. This review focuses on the role of epigenetic control in B cell biology which can provide clues for the study of potential novel pathogenic defects involved in PADs. PMID:26984849

  20. Polyreactive Antibodies: Function and Quantification

    PubMed Central

    Gunti, Sreenivasulu; Notkins, Abner Louis

    2015-01-01

    Polyreactive antibodies, a major component of the natural antibody repertoire, bind with low affinity to a variety of structurally unrelated antigens. Many of these antibodies are germline or near germline in sequence. Little is known, however, about the function of these antibodies. In the present mini-review we show: (1) that the broad antibacterial activity of the natural antibody repertoire is largely due to polyreactive antibodies, which in the presence of complement lyse bacteria and enhance phagocytosis; (2) that polyreactive antibodies bind to UV- or human immunodeficiency virus-induced apoptotic cells and with complement enhance the phagocytosis of these cells by macrophages; and (3) that dinitrophenol can be used as a surrogate for quantitating the level of polyreactive antibodies in serum. We conclude that polyreactive antibodies protect the host against both foreign invaders and its own damaged/apoptotic cells. PMID:26116731

  1. Accommodation and antibodies.

    PubMed

    Dehoux, Jean-Paul; Gianello, Pierre

    2009-06-01

    Accommodation refers to the condition in which an organ transplant functions normally by acquiring resistance to immune-mediated injury (especially), despite the presence of anti-transplant antibodies in the recipient. This status is associated with several modifications in the recipient as well as in the graft, such as previous depletion of anti-graft antibodies and their slow return once the graft is placed; expression of several protective genes in the graft; a Th2 immune response in the recipient; and inhibition of the membrane attack complex of complement. PMID:18973811

  2. Antibody determination in the diagnosis of Wuchereria bancrofti infection in man

    PubMed Central

    Dissanayake, S.; Ismail, M. M.

    1981-01-01

    The levels of IgG and IgE antibodies reacting with somatic antigens of adult Setaria digitata and Wuchereria bancrofti microfilariae were determined in sera of 90 patients with Bancroftian filariasis and 379 non-filarial subjects. Antibodies reacting with adult antigens and with soluble microfilarial antigens were seen in both microfilaraemic and amicrofilaraemic patients. Antibodies reacting with surface antigens of W. bancrofti microfilariae were seen only in amicrofilaraemic subjects. IgE antibodies were detected with the adult antigen only in both microfilaraemic and amicrofilaraemic patients. The absolute levels of IgG antibodies were significantly higher than those of IgE antibodies. It is concluded that the determination of serum antibodies reacting with adult antigens is suitable for the diagnosis of both the microfilaraemic and amicrofilaraemic phases of infection, and the determination of antibody to microfilarial surface antigens is applicable in patients with clinically evident disease. PMID:7032737

  3. Monoclonal Antibodies against Pectin

    PubMed Central

    Liners, Françoise; Letesson, Jean-Jacques; Didembourg, Christian; Van Cutsem, Pierre

    1989-01-01

    Monoclonal antibodies have been produced that recognize a conformation of homopolygalacturonic acid (pectic acid) induced by an optimum concentration of calcium and sodium of about 1 and 150 millinormal, respectively. The epitope recognized is probably part of the dimers of pectin chains associated according to the `egg box' model. Images Figure 2 PMID:16667195

  4. Reshaping Antibody Diversity

    PubMed Central

    Wang, Feng; Ekiert, Damian C.; Ahmad, Insha; Yu, Wenli; Zhang, Yong; Bazirgan, Omar; Torkamani, Ali; Raudsepp, Terje; Mwangi, Waithaka; Criscitiello, Michael F.; Wilson, Ian A.; Schultz, Peter G.; Smider, Vaughn V.

    2014-01-01

    Summary Unlike humans or mice, some species have limited genome encoded combinatorial diversity potential, yet mount a robust antibody response. Cows are unusual in having exceptionally long CDR H3 loops and few V-regions, but the mechanism for creating diversity is not understood. Deep sequencing revealed that ultralong CDR H3s contain a remarkable complexity of cysteines, suggesting that disulfide-bonded mini-domains may arise during repertoire development. Indeed, crystal structures of two cow antibodies reveal that these CDR H3s form a very unusual architecture composed of a β-strand “stalk” that supports a structurally diverse, disulfide-bonded, “knob” domain. Sequence analysis suggests that diversity arises from somatic hypermutation of an ultralong DH with a severe codon bias towards mutation to cysteine. These unusual antibodies can be elicited to recognize defined antigens through the knob domain. Thus, the bovine immune system produces an antibody repertoire composed of CDR H3s of unprecedented length that fold into a diversity of mini-domains generated through combinations of somatically generated disulfides. PMID:23746848

  5. Detection of novel diagnostic antibodies in ankylosing spondylitis: An overview.

    PubMed

    Quaden, Dana H F; De Winter, Liesbeth M; Somers, Veerle

    2016-08-01

    Ankylosing spondylitis (AS) is a debilitating, chronic, rheumatic disease characterized by inflammation and new bone formation resulting in fusion of the spine and sacroiliac joints. Since early treatment is impeded by a delayed diagnosis, it is highly important to find new biomarkers that improve early diagnosis and may also contribute to a better assessment of disease activity, prognosis and therapy response in AS. Because of the absence of rheumatoid factor, AS was long assumed to have a seronegative character and antibodies are thus not considered a hallmark of the disease. However, emerging evidence suggests plasma cells and autoantibodies to be involved in the disease course. In this review, the role of B cells and antibodies in AS is discussed. Furthermore, an overview is provided of antibodies identified in AS up till now, and their diagnostic potential. Many of these antibody responses were based on small study populations and further validation is lacking. Moreover, most were identified by a hypothesis-driven approach and thus limited to antibodies against targets that are already known to be involved in AS pathogenesis. Hence, we propose an unbiased approach to identify novel diagnostic antibodies. The already successfully applied techniques cDNA phage display and serological antigen selection will be used to identify antibodies against both known and new antigen targets in AS plasma. These newly identified antibodies will enhance early diagnosis of AS and provide more insight into the underlying disease pathology, resulting in a more effective treatment strategy and eventually an improved disease outcome. PMID:27288842

  6. Demonstration of Usutu virus antibodies in horses, Croatia.

    PubMed

    Barbic, Ljubo; Vilibic-Cavlek, Tatjana; Listes, Eddy; Stevanovic, Vladimir; Gjenero-Margan, Ira; Ljubin-Sternak, Suncanica; Pem-Novosel, Iva; Listes, Irena; Mlinaric-Galinovic, Gordana; Di Gennaro, Annapia; Savini, Giovanni

    2013-10-01

    We report the first serological evidence of Usutu virus (USUV) infection in horses in Croatia. During 2011, 1380 horse serum samples from healthy animals were collected from six northern Croatian counties. All samples were first screened for West Nile virus (WNV) immunoglobulin G (IgG) antibodies using an enzyme-linked immunosorbent assay (ELISA). Sixty-nine WNV ELISA-reactive samples were further tested for WNV antibodies by a virus neutralization assay (VN assay) and plaque reduction neutralization test (PRNT), and USUV by a VN assay and tick-borne encephalitis virus (TBEV) antibodies by PRNT. During the same period, 306 human serum samples from patients coming for routine testing with no symptoms of acute febrile disease were tested for USUV IgG using ELISA. Reactive samples were tested for both USUV and WNV using a VN assay. USUV-specific neutralizing antibodies were detected in two of 69 WNV ELISA-reactive horse serum samples. Seropositive animals were found in two different regions of Croatia. One additional sample showed specific WNV-neutralizing antibodies that cross-neutralized USUV. Only one human sample (0.3%) was reactive to USUV antibodies in an ELISA test. In a confirmatory test, WNV-neutralizing antibodies were detected, indicating cross-reactive antibodies with USUV in ELISA. The exposure to USUV was documented in two WNV ELISA-reactive horses at distant locations. These results indicate the presence of USUV in northern Croatia. PMID:23808977

  7. The Art of Making Antibodies.

    ERIC Educational Resources Information Center

    Headon, Denis R.

    1986-01-01

    Provides background information for teachers on the nature and production of antibodies. Points out that the production of monoclonal antibodies blends the malignant with the beneficial to create a medical tool of exciting potential. (JN)

  8. Anti-insulin antibody test

    MedlinePlus

    Insulin antibodies - serum; Insulin Ab test ... Normally, there are no antibodies against insulin in your blood. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or ...

  9. Red Blood Cell Antibody Identification

    MedlinePlus

    ... be limited. Home Visit Global Sites Search Help? RBC Antibody Identification Share this page: Was this page helpful? Also known as: Alloantibody Identification; Antibody ID, RBC; RBC Ab ID Formal name: Red Blood Cell ...

  10. Anti-smooth muscle antibody

    MedlinePlus

    ... medlineplus.gov/ency/article/003531.htm Anti-smooth muscle antibody To use the sharing features on this page, please enable JavaScript. Anti-smooth muscle antibody is a blood test that detects the ...

  11. Lupus anticoagulants and antiphospholipid antibodies

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000547.htm Lupus anticoagulants and antiphospholipid antibodies To use the sharing features on this page, please enable JavaScript. Lupus anticoagulants are antibodies against substances in the lining ...

  12. Lupus anticoagulants and antiphospholipid antibodies

    MedlinePlus

    ... may make the diagnosis of antiphospholipid antibody syndrome (APS) if: You have had a blood clot or ... your risk of blood clots. ANTIPHOSPHOLIPID ANTIBODY SYNDROME (APS) In general you will need long-term treatment ...

  13. Humanized Antibodies for Antiviral Therapy

    NASA Astrophysics Data System (ADS)

    Co, Man Sung; Deschamps, Marguerite; Whitley, Richard J.; Queen, Cary

    1991-04-01

    Antibody therapy holds great promise for the treatment of cancer, autoimmune disorders, and viral infections. Murine monoclonal antibodies are relatively easy to produce but are severely restricted for therapeutic use by their immunogenicity in humans. Production of human monoclonal antibodies has been problematic. Humanized antibodies can be generated by introducing the six hypervariable regions from the heavy and light chains of a murine antibody into a human framework sequence and combining it with human constant regions. We humanized, with the aid of computer modeling, two murine monoclonal antibodies against herpes simplex virus gB and gD glycoproteins. The binding, virus neutralization, and cell protection results all indicate that both humanized antibodies have retained the binding activities and the biological properties of the murine monoclonal antibodies.

  14. Trifunctional antibody ertumaxomab

    PubMed Central

    Diermeier-Daucher, Simone; Ortmann, Olaf; Buchholz, Stefan; Brockhoff, Gero

    2012-01-01

    Background: The trifunctional antibody ertumaxomab bivalently targets the human epidermal growth factor receptor 2 (Her2) on epithelial (tumor) cells and the T cell specific CD3 antigen, and its Fc region is selectively recognized by Fcγ type I/III receptor-positive immune cells. As a trifunctional immunoglobulin, ertumaxomab therefore not only targets Her2 on cancer cells, but also triggers immunological effector mechanisms mediated by T and accessory cells (e.g., macrophages, dendritic cells, natural killer cells). Whether molecular effects, however, might contribute to the cellular antitumor efficiency of ertumaxomab are largely unknown. Methods: Potential molecular effects of ertumaxomab on Her2-overexpressing BT474 and SK-BR-3 breast cancer cells were evaluated. The dissociation constant Kd of ertumaxomab was calculated from titration curves that were recorded by flow cytometry. Treatment-induced changes in Her2 homodimerization were determined by flow cytometric fluorescence resonance energy transfer measurements on a cell-by-cell basis. Potential activation / deactivation of Her2, ERK1/2, AKT and STAT3 were analyzed by western blotting, Immunochemistry and immunofluorescent cell staining. Results: The Kd of ertumaxomab for Her2-binding was determined at 265 nM and the ertumaxomab binding epitope was found to not overlap with that of the therapeutic anti-Her2 monoclonal antibodies trastuzumab and pertuzumab. Ertumaxomab caused an increase in Her2 phosphorylation at higher antibody concentrations, but changed neither the rate of Her2-homodimerization /-phosphorylation nor the activation state of key downstream signaling proteins analyzed. Conclusions: The unique mode of action of ertumaxomab, which relies more on activation of immune-mediated mechanisms against tumor cells compared with currently available therapeutic antibodies for breast cancer treatment, suggests that modular or sequential treatment with the trifunctional bivalent antibody might complement

  15. Therapeutic antibodies in ophthalmology

    PubMed Central

    Magdelaine-Beuzelin, Charlotte; Pinault, Coralie; Paintaud, Gilles

    2010-01-01

    More than a century after the first successful use of serotherapy, antibody-based therapy has been renewed by the availability of recombinant monoclonal antibodies. As in the past, current clinical experience has prompted new pharmacological questions and induced much debate among practitioners, notably in the field of ophthalmology. An examination of the history of antibodies as treatments for ocular disorders reveals interesting parallels to the modern era. The fact that a treatment administered by a systemic route could be efficacious in a local disease was not widely accepted and the “chemical” nature of antibodies was not clearly understood in the late 19th century. Clinical studies by Henry Coppez, a Belgian ophthalmologist, established in 1894 that antidiphtheric antitoxins could be used to treat conjunctival diphtheria. Nearly 20 years later, Coppez and Danis described age-related macular degeneration, a disorder which today benefits from ranibizumab therapy. The product, a locally-administered recombinant monoclonal Fab fragment, is directed against vascular endothelial growth factor A. Interestingly, its full-size counterpart, bevacizumab, which is approved for the treatment of solid tumors, has also demonstrated efficacy in age-related macular degeneration when administered either intravenously or locally, which raises new questions about antibody pharmacology and biodistribution. In order to shed some light on this debate, we recount the early history of serotherapy applied to ophthalmology, review the exact molecular differences between ranibizumab and bevacizumab, and discuss what is known about IgG and the blood-retina barrier and the possible role of FcRn, an IgG transporter. PMID:21358858

  16. Antibody-gold cluster conjugates

    DOEpatents

    Hainfeld, J.F.

    1988-06-28

    Antibody- or antibody fragment-gold cluster conjugates are shown wherein the conjugate size can be about 5.0 nm. Methods and reagents are disclosed in which antibodies or Fab' fragments thereof are covalently bound to a stable cluster of gold atoms. 2 figs.

  17. Natural antibodies and the host immune responses to xenografts.

    PubMed

    Cramer, D V

    2000-05-01

    Natural antibodies are present in the serum of individuals in the absence of known antigenic stimulation. These antibodies are primarily IgM, polyreactive, and encoded by immunoglobulin V genes in germline configuration. Natural antibodies are produced by B-1 lymphocytes, cells that form the primary cell of the fetal and newborn B cell repertoire and may represent the basic foundation upon which the adult repertoire of B cell antibodies is based. Natural antibodies react with a variety of endogenous and exogenous antigens, including xenoantigens expressed by tissues between unrelated species. These antibodies are capable of causing the immediate rejection of grafts exchanged across species barriers. One of the central issues related to our understanding of the immunopathologic mechanisms responsible for rejection of xenografts is whether pre-formed natural antibodies and new antibodies induced following xenotransplantation are produced by the same pathways of B cell antibody production. We have established in studies conducted in rodents and humans that the initial phases of antibody production xenogeneic tissues involves the use of a restricted population of Ig germline genes to encode xenoantibody binding. As the humoral xenoantibody response matures, the same closely-related groups of Ig V genes are used to encode antibody binding and there is evidence for an isotype switch to IgG antibody production and the appearance of somatic mutations consistent with antigen-driven affinity maturation. Our findings in both rodent and human studies form the basis for our proposal that the xenograft response reflects the use of B cell natural antibody repertoires originally intended to provide protection against infection. The host humoral response is inadvertently recruited to mount antibody responses against foreign grafts because they display carbohydrate antigens that are shared by common environmental microbes. This model of xenoantibody responses is being tested in our

  18. Antibody mimetics: promising complementary agents to animal-sourced antibodies.

    PubMed

    Baloch, Abdul Rasheed; Baloch, Abdul Wahid; Sutton, Brian J; Zhang, Xiaoying

    2016-01-01

    Despite their wide use as therapeutic, diagnostic and detection agents, the limitations of polyclonal and monoclonal antibodies have inspired scientists to design the next generation biomedical agents, so-called antibody mimetics that offer many advantages over conventional antibodies. Antibody mimetics can be constructed by protein-directed evolution or fusion of complementarity-determining regions through intervening framework regions. Substantial progress in exploiting human, butterfly (Pieris brassicae) and bacterial systems to design and select mimetics using display technologies has been made in the past 10 years, and one of these mimetics [Kalbitor® (Dyax)] has made its way to market. Many challenges lie ahead to develop mimetics for various biomedical applications, especially those for which conventional antibodies are ineffective, and this review describes the current characteristics, construction and applications of antibody mimetics compared to animal-sourced antibodies. The possible limitations of mimetics and future perspectives are also discussed. PMID:25264572

  19. Antibody Engineering and Therapeutics Conference

    PubMed Central

    Almagro, Juan Carlos; Gilliland, Gary L; Scott, Jamie; Larrick, James W; Plückthun, Andreas; Veldman, Trudi; Adams, Gregory P; Parren, Paul WHI; Chester, Kerry A; Bradbury, Andrew; Reichert, Janice M; Huston, James S

    2013-01-01

    The Antibody Engineering and Therapeutics conference, which serves as the annual meeting of The Antibody Society, will be held in Huntington Beach, CA from Sunday December 8 through Thursday December 12, 2013. The scientific program will cover the full spectrum of challenges in antibody research and development, and provide updates on recent progress in areas from basic science through approval of antibody therapeutics. Keynote presentations will be given by Leroy Hood (Institute of System Biology), who will discuss a systems approach for studying disease that is enabled by emerging technology; Douglas Lauffenburger (Massachusetts Institute of Technology), who will discuss systems analysis of cell communication network dynamics for therapeutic biologics design; David Baker (University of Washington), who will describe computer-based design of smart protein therapeutics; and William Schief (The Scripps Research Institute), who will discuss epitope-focused immunogen design.   In this preview of the conference, the workshop and session chairs share their thoughts on what conference participants may learn in sessions on: (1) three-dimensional structure antibody modeling; (2) identifying clonal lineages from next-generation data sets of expressed VH gene sequences; (3) antibodies in cardiometabolic medicine; (4) the effects of antibody gene variation and usage on the antibody response; (5) directed evolution; (6) antibody pharmacokinetics, distribution and off-target toxicity; (7) use of knowledge-based design to guide development of complementarity-determining regions and epitopes to engineer or elicit the desired antibody; (8) optimizing antibody formats for immunotherapy; (9) antibodies in a complex environment; (10) polyclonal, oligoclonal and bispecific antibodies; (11) antibodies to watch in 2014; and (12) polyreactive antibodies and polyspecificity.

  20. Targeting antibodies to the cytoplasm

    PubMed Central

    Marschall, Andrea L J; Frenzel, André; Schirrmann, Thomas; Schüngel, Manuela

    2011-01-01

    A growing number of research consortia are now focused on generating antibodies and recombinant antibody fragments that target the human proteome. A particularly valuable application for these binding molecules would be their use inside a living cell, e.g., for imaging or functional intervention. Animal-derived antibodies must be brought into the cell through the membrane, whereas the availability of the antibody genes from phage display systems allows intracellular expression. Here, the various technologies to target intracellular proteins with antibodies are reviewed. PMID:21099369

  1. [Antibody therapy for Alzheimer's disease].

    PubMed

    Tabira, Takeshi; Matsumoto, Shin-Ei; Jin, Haifeng

    2011-11-01

    In order to avoid Abeta-induced autoimmune encephalitis, several monoclonal and polyclonal antibodies are in clinical trials. These are bapineuzumab, solanezumab, ponezumab, gantenerumab, BAN2401, gammaguard and octagam. Since each antibody has a different antigen epitope of Abeta, anti-amyloid activities are different. It is unknown which antibody is effective for Alzheimer disease, and we must wait for the result of clinical trials. Some patients who developed tissue amyloid plaque immuno-reactive (TAPIR) antibody showed slower decline after AN-1792 vaccination. We developed TAPIR-like monoclonal antibody, which was found to react with Abeta oligomers preferentially. PMID:22277519

  2. Monoclonal antibodies to gonadotropin subunits

    SciTech Connect

    Ehrlich, P.H.; Moyle, W.R.; Canfield, R.E.

    1985-01-01

    The production of monoclonal antibodies to peptide hormones, with their unifocal binding sites, can provide tools for understanding hormone structure and function. The paper focuses on techniques that are important for the study of monoclonal antibodies to chorionic gonadotropin (hCG), including hybridoma production, methods of screening for desired clones, properties of the monoclonal antibodies, effect of antibodies on hormone-receptor interaction, inhibition of binding of radiolabeled hCG, inhibition of hCG induced steroidogenesis, determination of relative orientation of epitopes, and synergistic actions of monoclonal antibodies to hCG.

  3. Antibody-mediated radiotherapy

    SciTech Connect

    Bloomer, W.D.; Lipsztein, R.; Dalton, J.F.

    1985-05-01

    Antibodies that react with antigens on the surface of tumor cells but not normal cells have great potential for cancer detection and therapy. If radiolabeled without loss of immunologic specificity, such antibodies may be able to deliver cytoxic amounts of radiation. Target- cell specificity and a high extraction coefficient are necessary with any radionuclide in order to minimize normal tissue irradiation. Tumor- cell-retention time and the rate of catabolized radionuclide will also influence ultimate applicability. Among the unanswered questions for choosing a radionuclide is the choice of particle emitter. Although classic beta emitters have been used in a number of clinical situations, they have not had a major impact on disease outcome except in diseases of the thyroid. Unfortunately, Auger emitters such as iodine 125 are cytotoxic only when localized within close proximity to the genome. On the other hand, alpha emitters such as astatine 211 eliminate the need for subcellular sequestration but not cell-specific localization. 34 references.

  4. Antibody Therapy for Histoplasmosis

    PubMed Central

    Nosanchuk, Joshua D.; Zancopé-Oliveira, Rosely M.; Hamilton, Andrew J.; Guimarães, Allan J.

    2012-01-01

    The endemic human pathogenic fungus Histoplasma capsulatum is a major fungal pathogen with a broad variety of clinical presentations, ranging from mild, focal pulmonary disease to life-threatening systemic infections. Although azoles, such as itraconazole and voriconazole, and amphotericin B have significant activity against H. capsulatum, about 1 in 10 patients hospitalized due to histoplasmosis die. Hence, new approaches for managing disease are being sought. Over the past 10 years, studies have demonstrated that monoclonal antibodies (mAbs) can modify the pathogenesis of histoplasmosis. Disease has been shown to be impacted by mAbs targeting either fungal cell surface proteins or host co-stimulatory molecules. This review will detail our current knowledge regarding the impact of antibody therapy on histoplasmosis. PMID:22347215

  5. Therapeutic antibodies against cancer

    PubMed Central

    Adler, Mark J.; Dimitrov, Dimiter S.

    2012-01-01

    Antibody-based therapeutics against cancer are highly successful in clinic and currently enjoy unprecedented recognition of their potential; 13 monoclonal antibodies (mAbs) have been approved for clinical use in the European Union and in the United States (one, mylotarg, was withdrawn from market in 2010). Three of the mAbs (bevacizumab, rituximab, trastuzumab) are in the top six selling protein therapeutics with sales in 2010 of more than $5 bln each. Hundreds of mAbs including bispecific mAbs and multispecific fusion proteins, mAbs conjugated with small molecule drugs and mAbs with optimized pharmacokinetics are in clinical trials. However, challenges remain and it appears that deeper understanding of mechanisms is needed to overcome major problems including resistance to therapy, access to targets, complexity of biological systems and individual variations. PMID:22520975

  6. Prediction of Antibody Epitopes.

    PubMed

    Nielsen, Morten; Marcatili, Paolo

    2015-01-01

    Antibodies recognize their cognate antigens in a precise and effective way. In order to do so, they target regions of the antigenic molecules that have specific features such as large exposed areas, presence of charged or polar atoms, specific secondary structure elements, and lack of similarity to self-proteins. Given the sequence or the structure of a protein of interest, several methods exploit such features to predict the residues that are more likely to be recognized by an immunoglobulin. Here, we present two methods (BepiPred and DiscoTope) to predict linear and discontinuous antibody epitopes from the sequence and/or the three-dimensional structure of a target protein. PMID:26424260

  7. Immunopotentiating Effect of Vinca Alkaloids on the Antibody Response to Sheep Red Blood Cells in the Mouse

    PubMed Central

    Byrd, J. Randall; Isa, Abdallah M.

    1981-01-01

    Evidence is presented that the vinca alkaloids (vinblastine, vincristine, and vindesine) exert an immunopotentiating effect on the antibody response to sheep red blood cells (SRBC). The primary antibody response, measured by the rosette-forming cell (RFC) and hemagglutination (HA) assays, was enhanced by vincristine and vindesine treatments. Neither drug had any effect on the secondary antibody response. Vinblastine, while having no effect on the primary response, augmented the secondary antibody response to SRBC. PMID:7265281

  8. Antibody Production with Synthetic Peptides.

    PubMed

    Lee, Bao-Shiang; Huang, Jin-Sheng; Jayathilaka, Lasanthi P; Lee, Jenny; Gupta, Shalini

    2016-01-01

    Peptides (usually 10-20 amino acid residues in length) can be used as effectively as proteins in raising antibodies producing both polyclonal and monoclonal antibodies routinely with titers higher than 20,000. Peptide antigens do not function as immunogens unless they are conjugated to proteins. Production of high quality antipeptide antibodies is dependent upon peptide sequence selection, the success of peptide synthesis, peptide-carrier protein conjugation, the humoral immune response in the host animal, the adjuvant used, the peptide dose administered, the injection method, and the purification of the antibody. Peptide sequence selection is probably the most critical step in the production of antipeptide antibodies. Although the process for designing peptide antigens is not exact, several guidelines and computational B-cell epitope prediction methods can help maximize the likelihood of producing antipeptide antibodies that recognize the protein. Antibodies raised by peptides have become essential tools in life science research. Virtually all phospho-specific antibodies are now produced using phosphopeptides as antigens. Typically, 5-20 mg of peptide is enough for antipeptide antibody production. It takes 3 months to produce a polyclonal antipeptide antibody in rabbits that yields ~100 mL of serum which corresponds to ~8-10 mg of the specific antibody after affinity purification using a peptide column. PMID:27515072

  9. A monoclonal antibody against leptin.

    PubMed

    Mahmoudian, Jafar; Jeddi-Tehrani, Mahmood; Bayat, Ali Ahmad; Mahmoudi, Ahmad Reza; Vojgani, Yasaman; Tavangar, Banafsheh; Hadavi, Reza; Zarei, Saeed

    2012-10-01

    Leptin is an important protein that regulates energy storage and homeostasis in humans and animals. Leptin deficiency results in various abnormalities such as diabetes, obesity, and infertility. Producing a high affinity monoclonal antibody against human leptin provides an important tool to monitor and trace leptin function in different biological fluids. In this study, recombinant human leptin was conjugated to KLH and injected into mice. After immunization, mouse myeloma SP2/0 cells were fused with murine splenocytes followed by selection of antibody-producing hybridoma cells. After screening of different hybridoma colonies by ELISA, a high affinity antibody was selected and purified by affinity chromatography. The affinity constant of the antibody was measured by ELISA. Western blot, immunocytochemistry, and flow cytometry experiments were used to characterize the antibody. The anti-leptin antibody had a high affinity (around 1.13 × 10(-9) M) for its antigen. The saturation of the antibody with leptin (20 moles leptin per 1 mole antibody) in Western blot analysis proved that the antibody had specific binding to its antigen. Immunocytochemistry and flow cytometry on JEG-3 (human placental choriocarcinoma cell) cells revealed that the anti-leptin antibody recognized intracellular leptin. In conclusion, we report here the production and characterization of a murine anti-leptin antibody with high affinity for human leptin. PMID:23098305

  10. Commercial antibodies and their validation

    PubMed Central

    Voskuil, JLA

    2014-01-01

    Despite an impressive growth in the business of research antibodies a general lack of trust in commercial antibodies remains in place. A variety of issues, each one potentially causing an antibody to fail, underpin the frustrations that scientists endure. Lots of money goes to waste in buying and trying one failing antibody after the other without realizing all the pitfalls that come with the product: Antibodies can get inactivated, both the biological material and the assay itself can potentially be flawed, a single antibody featuring in many different catalogues can be deemed as a set of different products, and a bad choice of antibody type, wrong dilutions, and lack of proper validation can all jeopardize the intended experiments. Antibodies endorsed by scientific research papers do not always meet the scientist’s requirements either due to flawed specifications, or due to batch-to-batch variations. Antibodies can be found with Quality Control data obtained from previous batches that no longer represent the batch on sale. In addition, one cannot assume that every antibody is fit for every application. The best chance of success is to try an antibody that already was confirmed to perform correctly in the required platform. PMID:25324967

  11. Primary antibody deficiency syndromes.

    PubMed

    Wood, P

    2009-03-01

    The primary antibody deficiency syndromes are a group of rare disorders characterized by an inability to produce clinically effective immunoglobulin responses. Some of these disorders result from genetic mutations in genes involved in B cell development, whereas others appear to be complex polygenic disorders. They most commonly present with recurrent infections due to encapsulated bacteria, although in the most common antibody deficiency, Common Variable Immunodeficiency, systemic and organ-specific autoimmunity can be a presenting feature. Diagnostic delay in this group of disorders remains a problem, and the laboratory has a vital role in the detection of abnormalities in immunoglobulin concentration and function. It is critical to distinguish this group of disorders from secondary causes of hypogammaglobulinaemia, in particular lymphoid malignancy, and appropriate laboratory investigations are of critical importance. Treatment of primary antibody deficiencies involves immunoglobulin replacement therapy, either via the intravenous or subcutaneous route. Patients remain at risk of a wide variety of complications, not all linked to diagnostic delay and inadequate therapy. In common variable immunodeficiency (CVID) in particular, patients remain at significantly increased risk of lymphoid malignancy, and regular clinical and laboratory monitoring is required. This review aims to give an overview of these conditions for the general reader, covering pathogenesis, clinical presentation, laboratory investigation, therapy and clinical management. PMID:19151170

  12. Antibody therapy for Ebola

    PubMed Central

    Qiu, Xiangguo; Kobinger, Gary P

    2014-01-01

    Ebola viruses can cause severe hemorrhagic fever in humans and nonhuman primates with fatality rates up to 90%, and are identified as biosafety level 4 pathogens and CDC Category A Agents of Bioterrorism. To date, there are no approved therapies and vaccines available to treat these infections. Antibody therapy was estimated to be an effective and powerful treatment strategy against infectious pathogens in the late 19th, early 20th centuries but has fallen short to meet expectations to widely combat infectious diseases. Passive immunization for Ebola virus was successful in 2012, after over 15 years of failed attempts leading to skepticism that the approach would ever be of potential benefit. Currently, monoclonal antibody (mAbs)-based therapies are the most efficient at reversing the progression of a lethal Ebola virus infection in nonhuman primates, which recapitulate the human disease with the highest similarity. Novel combinations of mAbs can even fully cure lethally infected animals after clinical symptoms and circulating virus have been detected, days into the infection. These new developments have reopened the door for using antibody-based therapies for filovirus infections. Furthermore, they are reigniting hope that these strategies will contribute to better control the spread of other infectious agents and provide new tools against infectious diseases. PMID:24503566

  13. Maturation Pathways of Cross-Reactive HIV-1 Neutralizing Antibodies

    PubMed Central

    Xiao, Xiaodong; Chen, Weizao; Feng, Yang; Dimitrov, Dimiter S.

    2009-01-01

    Several human monoclonal antibodies (hmAbs) and antibody fragments, including the best characterized in terms of structure-function b12 and Fab X5, exhibit relatively potent and broad HIV-1 neutralizing activity. However, the elicitation of b12 or b12-like antibodies in vivo by vaccine immunogens based on the HIV-1 envelope glycoprotein (Env) has not been successful. B12 is highly divergent from the closest corresponding germline antibody while X5 is less divergent. We have hypothesized that the relatively high degree of specific somatic hypermutations may preclude binding of the HIV-1 envelope glycoprotein (Env) to closest germline antibodies, and that identifying antibodies that are intermediates in the pathways to maturation could help design novel vaccine immunogens to guide the immune system for their enhanced elicitation. In support of this hypothesis we have previously found that a germline-like b12 (monovalent and bivalent scFv as an Fc fusion protein or IgG) lacks measurable binding to an Env as measured by ELISA with a sensitivity in the μM range [1]; here we present evidence confirming and expanding these findings for a panel of Envs. In contrast, a germline-like scFv X5 bound Env with high (nM) affinity. To begin to explore the maturation pathways of these antibodies we identified several possible b12 intermediate antibodies and tested their neutralizing activity. These intermediate antibodies neutralized only some HIV-1 isolates and with relatively weak potency. In contrast, germline-like scFv X5 neutralized a subset of the tested HIV-1 isolates with comparable efficiencies to that of the mature X5. These results could help explain the relatively high immunogenicity of the coreceptor binding site on gp120 and the abundance of CD4-induced (CD4i) antibodies in HIV-1-infected patients (X5 is a CD4i antibody) as well as the maturation pathway of X5. They also can help identify antigens that can bind specifically to b12 germline and intermediate antibodies

  14. Serum lymphocytotoxic antibodies and neurocognitive function in systemic lupus erythematosus.

    PubMed Central

    Long, A A; Denburg, S D; Carbotte, R M; Singal, D P; Denburg, J A

    1990-01-01

    The hypothesis that lymphocytotoxic antibodies are associated with neuropsychiatric involvement in systemic lupus erythematosus (NP-SLE) is re-evaluated in this study. In an unselected cohort of 98 women with SLE a cross-sectional study has been performed to analyse associations among standardised clinical, neurological, and neuropsychological assessments and lymphocytotoxic antibodies measured by microcytotoxicity assay. Fifty patients showed objective clinical evidence of continuing or past NP-SLE and 54 patients had cognitive impairment. In accordance with previous observations 44% (24/54) of the cognitively impaired group did not have clinically detectable evidence of NP-SLE. Although lymphocytotoxic antibodies were found to be only marginally more prevalent in those patients with a clinical diagnosis of NP-SLE than in those without (32% v 23%), these antibodies were significantly associated with cognitive impairment (chi 2 = 5.42; p less than 0.02). No association was detected between lymphocytotoxic antibodies and either overall systemic disease activity or other organ system involvement, suggesting that the association between lymphocytotoxic antibodies and cognitive dysfunction in SLE is specific. PMID:2339907

  15. Antibody-mediated neutralization of African swine fever virus: myths and facts.

    PubMed

    Escribano, José M; Galindo, Inmaculada; Alonso, Covadonga

    2013-04-01

    Almost all viruses can be neutralized by antibodies. However, there is some controversy about antibody-mediated neutralization of African swine fever virus (ASFV) with sera from convalescent pigs and about the protective relevance of antibodies in experimentally vaccinated pigs. At present, there is no vaccine available for this highly lethal and economically relevant virus and all classical attempts to generate a vaccine have been unsuccessful. This failure has been attributed, in part, to what many authors describe as the absence of neutralizing antibodies. The findings of some studies clearly contradict the paradigm of the impossibility to neutralize ASFV by means of monoclonal or polyclonal antibodies. This review discusses scientific evidence of these types of antibodies in convalescent and experimentally immunized animals, the nature of their specificity, the neutralization-mediated mechanisms demonstrated, and the potential relevance of antibodies in protection. PMID:23159730

  16. Antibodies to West Nile Virus in Wild and Farmed Crocodiles in Southeastern Mexico

    PubMed Central

    Machain-Williams, Carlos; Padilla-Paz, Sergio E.; Weber, Manuel; Cetina-Trejo, Rosa; Juarez-Ordaz, José Alfredo; Loroño-Pino, María Alba; Ulloa, Armando; Wang, Chong; Garcia-Rejon, Julián; Blitvich, Bradley J.

    2013-01-01

    Surveillance for evidence of West Nile virus (WNV) infection in Morelet’s crocodiles (Crocodylus moreletii) was conducted in Campeche State, Mexico, in 2007. Sera from 62 crocodiles (32 free-ranging and 30 captive) were assayed for antibodies to WNV by epitope-blocking enzyme-linked immunosorbent assay. Antibodies to WNV were detected in 13 (41%) wild and nine (30%) captive crocodiles, and the overall antibody prevalence was 35%. Although evidence of WNV infection in captive crocodiles has been reported in Mexico, we provide the first evidence of WNV exposure in wild crocodiles in Mexico. PMID:23778623

  17. Antibodies to West Nile virus in wild and farmed crocodiles in southeastern Mexico.

    PubMed

    Machain-Williams, Carlos; Padilla-Paz, Sergio E; Weber, Manuel; Cetina-Trejo, Rosa; Juarez-Ordaz, José Alfredo; Loroño-Pino, María Alba; Ulloa, Armando; Wang, Chong; Garcia-Rejon, Julián; Blitvich, Bradley J

    2013-07-01

    Surveillance for evidence of West Nile virus (WNV) infection in Morelet's crocodiles (Crocodylus moreletii) was conducted in Campeche State, Mexico, in 2007. Sera from 62 crocodiles (32 free-ranging and 30 captive) were assayed for antibodies to WNV by epitope-blocking enzyme-linked immunosorbent assay. Antibodies to WNV were detected in 13 (41%) wild and nine (30%) captive crocodiles, and the overall antibody prevalence was 35%. Although evidence of WNV infection in captive crocodiles has been reported in Mexico, we provide the first evidence of WNV exposure in wild crocodiles in Mexico. PMID:23778623

  18. Antibody dependent enhancement of frog virus 3 infection

    PubMed Central

    2010-01-01

    Background Viruses included in the family Iridoviridae are large, icosahedral, dsDNA viruses that are subdivided into 5 genera. Frog virus 3 (FV3) is the type species of the genus Ranavirus and the best studied iridovirus at the molecular level. Typically, antibodies directed against a virus act to neutralize the virus and limit infection. Antibody dependent enhancement occurs when viral antibodies enhance infectivity of the virus rather than neutralize it. Results Here we show that anti-FV3 serum present at the time of FV3 infection enhances infectivity of the virus in two non-immune teleost cell lines. We found that antibody dependent enhancement of FV3 was dependent on the Fc portion of anti-FV3 antibodies but not related to complement. Furthermore, the presence of anti-FV3 serum during an FV3 infection in a non-immune mammalian cell line resulted in neutralization of the virus. Our results suggest that a cell surface receptor specific to teleost cell lines is responsible for the enhancement. Conclusions This report represents the first evidence of antibody dependent enhancement in iridoviruses. The data suggests that anti-FV3 serum can either neutralize or enhance viral infection and that enhancement is related to a novel antibody dependent enhancement pathway found in teleosts that is Fc dependent. PMID:20167100

  19. Antineurofilament and antiretinal antibodies in AIDS patients with cytomegalovirus retinitis.

    PubMed Central

    Rosberger, D F; Tshering, S L; Polsky, B; Heinemann, M H; Klein, R F; Cunningham-Rundles, S

    1994-01-01

    Sera obtained from AIDS patients with cytomegalovirus (CMV) retinitis before and after treatment with foscarnet, AIDS patients with human immunodeficiency virus (HIV) retinopathy, AIDS patients without retinal disease, and normal healthy controls with and without positive CMV serologies were assayed for the presence of antibodies against the 200-kDa outer, 160-kDa middle, and 68-kDa core subunits of the neurofilament triplet. Additional studies were performed to determine the presence of antibodies reactive with proteins extracted from crude human retinal antigen preparations. Antibodies against the 200-, 260-, and 68-kDa proteins of the neurofilament triplet were detected in 15 of 15 AIDS patients with CMV retinitis. The expression of these antibodies was unaffected, qualitatively, by successful treatment with foscarnet. In contrast, only 30% of patients with HIV retinopathy unrelated to CMV, fewer than 35% of AIDS patients with positive CMV titers but without evident retinitis, and fewer than 25% of healthy controls with positive or negative CMV titers possessed antibodies against any of the triplet proteins (P < 0.001). Antibodies against several clusters of retinal antigens were also identified in the sera of patients with CMV retinitis. In summary, the data indicate that retinal elements damaged by CMV infection induce an antibody response against the 200-, 160-, and 68kDa components of the neurofilament triplet as well as other, as yet undefined retinal antigens. Images PMID:8556483

  20. NMDA receptor antibodies associated with distinct white matter syndromes

    PubMed Central

    Hacohen, Yael; Absoud, Michael; Hemingway, Cheryl; Jacobson, Leslie; Lin, Jean-Pierre; Pike, Mike; Pullaperuma, Sunil; Siddiqui, Ata; Wassmer, Evangeline; Waters, Patrick; Irani, Sarosh R.; Buckley, Camilla

    2014-01-01

    Objective: To report the clinical and radiologic findings of children with NMDA receptor (NMDAR) antibodies and white matter disorders. Method: Ten children with significant white matter involvement, with or without anti-NMDAR encephalitis, were identified from 46 consecutive NMDAR antibody–positive pediatric patients. Clinical and neuroimaging features were reviewed and the treatment and outcomes of the neurologic syndromes evaluated. Results: Three distinct clinicoradiologic phenotypes were recognized: brainstem encephalitis (n = 3), leukoencephalopathy following herpes simplex virus encephalitis (HSVE) (n = 2), and acquired demyelination syndromes (ADS) (n = 5); 3 of the 5 with ADS had myelin oligodendrocyte glycoprotein as well as NMDAR antibodies. Typical NMDAR antibody encephalitis was seen in 3 patients remote from the first neurologic syndrome (2 brainstem, 1 post-HSVE). Six of the 7 patients (85%) who were treated acutely, during the original presentation with white matter involvement, improved following immunotherapy with steroids, IV immunoglobulin, and plasma exchange, either individually or in combination. Two patients had escalation of immunotherapy at relapse resulting in clinical improvement. The time course of clinical features, treatments, and recoveries correlated broadly with available serum antibody titers. Conclusion: Clinicoradiologic evidence of white matter involvement, often distinct, was identified in 22% of children with NMDAR antibodies and appears immunotherapy responsive, particularly when treated in the acute phase of neurologic presentation. When observed, this clinical improvement is often mirrored by reduction in NMDAR antibody levels, suggesting that these antibodies may mediate the white matter disease. PMID:25340058

  1. Antibody Therapy for Pediatric Leukemia

    PubMed Central

    Vedi, Aditi; Ziegler, David S.

    2014-01-01

    Despite increasing cure rates for pediatric leukemia, relapsed disease still carries a poor prognosis with significant morbidity and mortality. Novel targeted therapies are currently being investigated in an attempt to reduce adverse events and improve survival outcomes. Antibody therapies represent a form of targeted therapy that offers a new treatment paradigm. Monoclonal antibodies are active in pediatric acute lymphoblastic leukemia (ALL) and are currently in Phase III trials. Antibody-drug conjugates (ADCs) are the next generation of antibodies where a highly potent cytotoxic agent is bound to an antibody by a linker, resulting in selective targeting of leukemia cells. ADCs are currently being tested in clinical trials for pediatric acute myeloid leukemia and ALL. Bispecific T cell engager (BiTE) antibodies are a construct whereby each antibody contains two binding sites, with one designed to engage the patient’s own immune system and the other to target malignant cells. BiTE antibodies show great promise as a novel and effective therapy for childhood leukemia. This review will outline recent developments in targeted agents for pediatric leukemia including monoclonal antibodies, ADCs, and BiTE antibodies. PMID:24795859

  2. Induction of antihemagglutinin antibodies by polyclonal antiidiotype antibodies.

    PubMed

    Dinca, L; Neuwirth, S; Schulman, J; Bona, C

    1993-01-01

    Antiidiotypic antibodies can be envisioned as an alternative approach in the development of vaccines against influenza virus, which exhibits natural antigenic variations. In our work, we obtained two polyclonal cross-reactive anti-Id antibodies against PY102, VM113, and VM202 mAbs, which in turn are specific respectively for PR8 virus and laboratory-induced virus variants (PY102-V1 and VM113-V1). With these cross-reactive anti-Id antibodies, we were able to elicit anti-HA antibodies in mice. In comparing the anti-HA antibody response in animals injected with anti-Id antibodies to those immunized with PR8 influenza virus, we demonstrated that the HI titer was higher after virus immunization and that the PR8 virus boost was more efficient in this group. Our results showed that the polyclonal cross-reactive anti-Id antibodies were more efficient than the individual anti-Ids at eliciting responses. At the same time, we demonstrated that PR8-primed T cells, cultured with B cells from animals immunized with anti-Id antibodies, were able to produce anti-PR8 antibodies subsequent to stimulation with influenza virus. PMID:8476510

  3. How antibodies use complement to regulate antibody responses.

    PubMed

    Sörman, Anna; Zhang, Lu; Ding, Zhoujie; Heyman, Birgitta

    2014-10-01

    Antibodies, forming immune complexes with their specific antigen, can cause complete suppression or several 100-fold enhancement of the antibody response. Immune complexes containing IgG and IgM may activate complement and in such situations also complement components will be part of the immune complex. Here, we review experimental data on how antibodies via the complement system upregulate specific antibody responses. Current data suggest that murine IgG1, IgG2a, and IgG2b upregulate antibody responses primarily via Fc-receptors and not via complement. In contrast, IgM and IgG3 act via complement and require the presence of complement receptors 1 and 2 (CR1/2) expressed on both B cells and follicular dendritic cells. Complement plays a crucial role for antibody responses not only to antigen complexed to antibodies, but also to antigen administered alone. Lack of C1q, but not of Factor B or MBL, severely impairs antibody responses suggesting involvement of the classical pathway. In spite of this, normal antibody responses are found in mice lacking several activators of the classical pathway (complement activating natural IgM, serum amyloid P component (SAP), specific intracellular adhesion molecule-grabbing non-integrin R1 (SIGN-R1) or C-reactive protein. Possible explanations to these observations will be discussed. PMID:25001046

  4. Antibody Glossary —

    Cancer.gov

    The components of the immune system have diverse roles in the initial development of cancers, progression of early-stage malignancies to invasive tumors, establishment of metastatic lesions, tumor dormancy, and response or resistance to therapy. Characterizing the components of the immune system and their functional status in tissues and in tumors requires the use of highly specific reagents. Researchers employ antibodies in a variety of in vitro and in vivo applications to delineate, enrich, or deplete specific immune subsets in order to understand their role(s) in tumorigenesis. This is a glossary of validated reagents and protocols that are useful for functional phenotyping of the immune system in murine cancer models.

  5. [Targeted therapy by monoclonal antibodies].

    PubMed

    Ohnuma, Kei; Morimoto, Chikao

    2010-10-01

    Human monoclonal antibodies are virtually indispensable for immunotherapy of cancer, infectious diseases, autoimmune diseases, or organ transplantation. The hybridoma technique, developed by Georges Köhler and César Milstein in 1975, has been shown to be most and highly producible method for generating murine monoclonal antibodies. However, poor results were obtained when it was administered in human bodies. With development of biotechnology, human monoclonal antibodies have been manufactured with higher efficiency. A major hindrance of producing therapeutic human monoclonal antibodies is the lack of an appropriate strategy for determining and selecting the antibodies that would be effective in vivo. In this review, we give an overview of the present techniques on therapeutic monoclonal antibodies. PMID:20954327

  6. Antiphospholipid antibodies: Paradigm in transition

    PubMed Central

    Horstman, Lawrence L; Jy, Wenche; Bidot, Carlos J; Ahn, Yeon S; Kelley, Roger E; Zivadinov, Robert; Maghzi, Amir H; Etemadifar, Masoud; Mousavi, Seyed Ali; Minagar, Alireza

    2009-01-01

    Objectives This is a critical review of anti-phospholipid antibodies (aPL). Most prior reviews focus on the aPL syndrome (APS), a thrombotic condition often marked by neurological disturbance. We bring to attention recent evidence that aPL may be equally relevant to non-thrombotic autoimmune conditions, notably, multiple sclerosis and ITP. Organization After a brief history, the recent proliferation of aPL target antigens is reviewed. The implication is that many more exist. Theories of aPL in thrombosis are then reviewed, concluding that all have merit but that aPL may have more diverse pathological consequences than now recognized. Next, conflicting results are explained by methodological differences. The lupus anticoagulant (LA) is then discussed. LA is the best predictor of thrombosis, but why this is true is not settled. Finally, aPL in non-thrombotic disorders is reviewed. Conclusion The current paradigm of aPL holds that they are important in thrombosis, but they may have much wider clinical significance, possibly of special interest in neurology. PMID:19154576

  7. Antibody Affinity Maturation in Fishes—Our Current Understanding

    PubMed Central

    Magor, Brad G.

    2015-01-01

    It has long been believed that fish lack antibody affinity maturation, in part because they were thought to lack germinal centers. Recent research done on sharks and bony fishes indicates that these early vertebrates are able to affinity mature their antibodies. This article reviews the functionality of the fish homologue of the immunoglobulin (Ig) mutator enzyme activation-induced cytidine deaminase (AID). We also consider the protein and molecular evidence for Ig somatic hypermutation and antibody affinity maturation. In the context of recent evidence for a putative proto-germinal center in fishes we propose some possible reasons that observed affinity maturation in fishes often seems lacking and propose future work that might shed further light on this process in fishes. PMID:26264036

  8. Empowered Antibody Therapies - IBC conference.

    PubMed

    Herold, Jens

    2010-10-01

    The Empowered Antibody Therapies conference, held in Burlingame, CA, USA, included topics covering new therapeutic developments in the field of multispecific antibodies. This conference report highlights selected presentations on DVD-Igs from Abbott Laboratories, ImmTACs from Immunocore, 'Dock-and-Lock' technology from Immunomedics, the bispecific BiTE antibody blinatumomab from Micromet, and Triomabs from TRION Pharma and Fresenius Biotech. PMID:20878591

  9. Antibodies as stratagems against cancer.

    PubMed

    Papageorgiou, Louis; Cuong, Nguyen Tien; Vlachakis, Dimitrios

    2016-06-21

    Antibodies have been in the frontline of anticancer research during the last few decades, since a number of different ways have been discovered to utilize them as parts or main components of anticancer drugs. Antibodies are used as the only component of some anticancer drugs, but they can also be conjugated with a variety of substances. Antibody engineering methods such as humanization, chimerization and Fc engineering are applied in order to modify their properties according to the requirements of anticancer drug application. Given the continuous advances in biology and informatics, the role of antibodies in anticancer treatment is expected to be prominent. PMID:26738941

  10. Immunological effects of the anti-programmed death-1 antibody on human peripheral blood mononuclear cells.

    PubMed

    Akiyama, Yasuto; Nonomura, Chizu; Kondou, Ryota; Miyata, Haruo; Ashizawa, Tadashi; Maeda, Chie; Mitsuya, Koichi; Hayashi, Nakamasa; Nakasu, Yoko; Yamaguchi, Ken

    2016-09-01

    Immune checkpoint antibody-mediated blockade has gained attention as a new cancer immunotherapy strategy. Accumulating evidence suggests that this therapy imparts a survival benefit to metastatic melanoma and non-small cell lung cancer patients. A substantial amount of data on immune checkpoint antibodies has been collected from clinical trials; however, the direct effect of the antibodies on human peripheral blood mononuclear cells (PBMCs) has not been exclusively investigated. In this study, we developed an anti-programmed death-1 (PD-1) antibody (with biosimilarity to nivolumab) and examined the effects of the antibody on PBMCs derived from cancer patients. Specifically, we investigated the effects of the anti-PD-1 antibody on proliferation, cytokine production, cytotoxic T lymphocytes (CTL) and regulatory T cells. These investigations yielded several important results. First, the anti-PD-1 antibody had no obvious effect on resting PBMCs; however, high levels of the anti-PD-1 antibody partly stimulated PBMC proliferation when accompanied by an anti-CD3 antibody. Second, the anti-PD-1 antibody restored the growth inhibition of anti-CD3 Ab-stimulated PBMCs mediated by PD-L1. Third, the anti-PD-1 antibody exhibited a moderate inhibitory effect on the induction of myeloid-derived suppressor cells (MDSCs) by anti-CD3 antibody stimulation. Additionally, the presence of the anti-PD-1 antibody promoted antigen-specific CTL induction, which suggests that combining anti-PD-1 antibody and conventional immunotherapy treatments may have beneficial effects. These results indicate that specific cellular immunological mechanisms are partly responsible for the antitumor effect exhibited by the anti-PD-1 antibody against advanced cancers in clinical trials. PMID:27573705

  11. An association between antibodies specific for endothelial cells and renal transplant failure.

    PubMed

    Perrey, C; Brenchley, P E; Johnson, R W; Martin, S

    1998-06-01

    Human leucocyte antigen (HLA)-specific antibodies, present at the time of transplant, cause renal transplant rejection but cases of rejection of HLA-identical renal transplants indicate that antibodies to non-HLA antigens may also be detrimental. There is increasing evidence that antibodies to antigens present on endothelial cells and monocytes, and on endothelial cells alone, are associated with transplant rejection. We investigated 105 patients with failed renal transplants for the presence of endothelial cell reactive antibodies and compared them with 94 successful transplant patients to determine the role of non-HLA antibodies in transplant failure. Patient sera were tested by enzyme-linked immunoabsorbent assay (ELISA) using as a target fixed cells either from the endothelial/epithelial cell line EAHy.926 or primary cultures of human umbilical vein endothelial cells. Antibody binding was detected using an alkaline phosphatase-conjugated anti-human immunoglobulin G (IgG) antibody. Fourteen of the 105 failed transplant patients had endothelial cell-reactive antibodies as compared with only three of the 94 patients with successful transplants (Fisher's exact test, p = 0.02). Antibody-positive sera were absorbed with the epithelial cell line A549 to remove antibodies directed against the epithelial component of EAHy.926 and with a pool of lymphoblastoid cell line cells to remove HLA-specific antibodies. Absorption did not reduce antibody activity showing the antibodies to be directed against endothelial cell determinants. Antibody-positive sera were also tested by flow cytometry against the monocyte cell line THP-1 and 13 of the 14 patients were negative. In conclusion, we have demonstrated the presence of IgG antibodies directed against endothelial cell determinants in renal transplant recipients in association with renal transplant failure. PMID:9777698

  12. Monoclonal antibodies and neuroblastoma

    SciTech Connect

    Miraldi, F. )

    1989-10-01

    Several antineuroblastoma monoclonal antibodies (MoAbs) have been described and two have been used in radioimmunoimaging and radioimmunotherapy in patients. MoAb 3F8 is a murine IgG3 antibody specific for the ganglioside GD2. Radioiodine-labeled 3F8 has been shown to specifically target human neuroblastoma in patients, and radioimmunoimaging with this agent has provided consistently high uptakes with tumor-to-background ratios of greater than or equal to 10:1. Radioimmunotherapy has been attempted with both MoAb 3F8 and MoAb UJ13A, and although encouraging results have been obtained, dosimetry data and tissue dose response information for these agents is lacking, which impedes the development of such therapy. 124I, a positron emitter, can be used with 3F8 in positron emission tomography (PET) scanning to provide dosimetry information for radioimmunotherapy. The tumor radiation dose response from radiolabeled MoAb also can be followed with PET images with fluorodeoxyglucose (FDG) scanning of neuroblastoma tumors. Results to date indicate that radioimmunoimaging has clinical use in the diagnosis of neuroblastoma and the potential for radioimmunotherapy for this cancer remains high.48 references.

  13. Prospects for engineering HIV-specific antibodies for enhanced effector function and half-life

    PubMed Central

    Boesch, Austin W.; Alter, Galit; Ackerman, Margaret E.

    2015-01-01

    Purpose of review A wealth of recent animal model data suggests that as exciting possibilities for the use of antibodies in passive immunotherapy strategies continue to develop, it will be important to broadly consider how antibodies achieve anti-HIV-1 effect in vivo. Recent findings Beyond neutralization breadth and potency, substantial evidence from natural infection, vaccination, and studies in animal models points to a critical role for antibody Fc receptor (FcR) engagement in reducing risk of infection, decreasing postinfection viremia, and delaying viral rebound. Supporting these findings in the setting of HIV, the clinical maturation of recombinant antibody therapeutics has reinforced the importance of Fc-driven activity in vivo across many disease settings, as well as opportunely resulted in the development and exploration of a number of engineered Fc sequence and glycosylation variants that possess differential binding to FcRs. Exploiting these variants as tools, the individual and concerted effects of antibody effector functions such as antibody-dependent cellular cytotoxicity, antibody-dependent cell-mediated virus inhibition, phagocytosis, complement-dependent cytotoxicity, antibody half-life, and compartmentalization are now being explored. As exciting molecular therapies are advanced, these studies promise to provide insight into optimal in-vivo antibody activity profiles. Summary Careful consideration of recent progress in understanding protective antibody activities in vivo can point toward how tailoring antibody activity via Fc domain modification may enable optimization of HIV prevention and eradication strategies. PMID:25700208

  14. Constant Domain-regulated Antibody Catalysis*

    PubMed Central

    Sapparapu, Gopal; Planque, Stephanie; Mitsuda, Yukie; McLean, Gary; Nishiyama, Yasuhiro; Paul, Sudhir

    2012-01-01

    Some antibodies contain variable (V) domain catalytic sites. We report the superior amide and peptide bond-hydrolyzing activity of the same heavy and light chain V domains expressed in the IgM constant domain scaffold compared with the IgG scaffold. The superior catalytic activity of recombinant IgM was evident using two substrates, a small model peptide that is hydrolyzed without involvement of high affinity epitope binding, and HIV gp120, which is recognized specifically by noncovalent means prior to the hydrolytic reaction. The catalytic activity was inhibited by an electrophilic phosphonate diester, consistent with a nucleophilic catalytic mechanism. All 13 monoclonal IgMs tested displayed robust hydrolytic activities varying over a 91-fold range, consistent with expression of the catalytic functions at distinct levels by different V domains. The catalytic activity of polyclonal IgM was superior to polyclonal IgG from the same sera, indicating that on average IgMs express the catalytic function at levels greater than IgGs. The findings indicate a favorable effect of the remote IgM constant domain scaffold on the integrity of the V-domain catalytic site and provide a structural basis for conceiving antibody catalysis as a first line immune function expressed at high levels prior to development of mature IgG class antibodies. PMID:22948159

  15. Creating Ordered Antibody Arrays with Antibody-Polymer Conjugates

    NASA Astrophysics Data System (ADS)

    Dong, Xuehui; Obermeyer, Allie; Olsen, Bradley

    Antibodies are a category of functional proteins that play crucial roles in the immune system and have been widely applied in the area of cancer therapeutics, targeting delivery, signal detection, and sensors. Due to the extremely large size and lack of specific functional groups on the surface, it is challenging to functionalize antibodies and manipulate the ordered packing of antibodies in an array with high density and proper orientation, which is critical to achieve outstanding performance in materials. In this work, we demonstrate an efficient and facile approach for preparing antibody-polymer conjugates with two-step sequential ``click'' reaction to form antibody-polymer block copolymers. Highly ordered nanostructures are fabricated based on the principles of block copolymer self-assembly. The nanostructures are studied with both small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Lamellae with alternating antibody domain and polymer domain are observed with an overall domain size of ~50 nm. The nanostructure not only increases the packing density and promotes proper orientation of the antibody, but also provides possible channel to facilitate substrate transportation and improves the stability of the antibody.

  16. Antibodies: Protective, destructive and regulatory role

    SciTech Connect

    Milgrom, F.; Abeyounis, C.J.; Albini, B.

    1985-01-01

    This book contains papers under 10 subject headings. The headings are: Production and Function of Antibodies, Protective Role of Antibodies, Antibodies to Foreign and Neoplastic Cells, Autoantibodies, Regulatory Mechanisms, Allergy, Immune Complexes, Antibodies in Pregnancy and Aging, Administration of Antibodies for Prevention and Therapy, and Abstracts of Poster Presentations.

  17. Antinuclear Antibodies (ANA)

    MedlinePlus

    ... drugs you take. ANA testing can produce a “false positive.” This typically signals the presence of antinuclear ... keep looking. In fact, you may have a “false positive” ANA, which means that the evidence is ...

  18. New engineered antibodies against prions

    PubMed Central

    Škrlj, Nives; Dolinar, Marko

    2014-01-01

    A number of recently developed and approved therapeutic agents based on highly specific and potent antibodies have shown the potential of antibody therapy. As the next step, antibody-based therapeutics will be bioengineered in a way that they not only bind pathogenic targets but also address other issues, including drug targeting and delivery. For antibodies that are expected to act within brain tissue, like those that are directed against the pathogenic prion protein isoform, one of the major obstacles is the blood-brain barrier which prevents efficient transfer of the antibody, even of the engineered single-chain variants. We recently demonstrated that a specific prion-specific antibody construct which was injected into the murine tail vein can be efficiently transported into brain tissue. The novelty of the work was in that the cell penetrating peptide was used as a linker connecting both specificity-determining domains of the antibody peptide, thus eliminating the need for the standard flexible linker, composed of an arrangement of three consecutive (Gly4Ser) repeats. This paves the road toward improved bioengineered antibody variants that target brain antigens. PMID:23941991

  19. [The significance of antiphospholipid antibodies].

    PubMed

    Fojtík, Z

    2004-04-01

    Antiphospholipid antibodies (APLA) present very heterogeneous groups of antibodies which can significantly influence processes on different levels of coagulation cascade depending on effects of phospholipid surfaces on blood coagulation. This usually leads to a particular level of thrombophylia. Clinical syndrome accompanying positive APLA, such as antiphospholipid syndrome, was defined by clinical and laboratory symptoms. This clinical syndrome can be a primary syndrome, if other disorders with ability to induce generation of antibodies can be excluded, or a secondary syndrome. The most often in cases of systemic tissue disease. APLA can be divided according to the presence of lupus anticoagulant and anticardiolipin antibodies. According to a definition lupus anticoagulants are antibodies able to inhibit and prolong in vitro one or more blood clotting processes dependent on phospholipid surfaces. Anticardiolipin antibodies are antibodies measured by ELISA method with cardiolipin used as an antibody. Findings show that some APLA are directed against proteins bound to phospholipid surfaces. Main cofactor proteins include beta 2-GPI and prothrombin. Because of their heterogeneous specificity, APLA are directed against negative phospholipids or proteins bound to phospholipid surfaces and have important pathophysiology role in development of antiphospholipid syndrome. PMID:15214303

  20. Micromechanical antibody sensor

    DOEpatents

    Thundat, Thomas G.; Jacobson, K. Bruce; Doktycz, Mitchel J.; Kennel, Stephen J.; Warmack, Robert J.

    2001-01-01

    A sensor apparatus is provided using a microcantilevered spring element having a coating of a detector molecule such as an antibody or antigen. A sample containing a target molecule or substrate is provided to the coating. The spring element bends in response to the stress induced by the binding which occurs between the detector and target molecules. Deflections of the cantilever are detected by a variety of detection techniques. The microcantilever may be approximately 1 to 200 .mu.m long, approximately 1 to 50 .mu.m wide, and approximately 0.3 to 3.0 .mu.m thick. A sensitivity for detection of deflections is in the range of 0.01 nanometers.

  1. Production of monoclonal antibodies.

    PubMed

    Freysd'ottir, J

    2000-01-01

    The discovery of monoclonal antibodies (mAbs) produced by "hybridoma technology" by George Köhler and Cesar Milstein in 1975 has had a great impact both on basic biological research and on clinical medicine. However, this impact was not immediately recognized. It took around 10 years to appreciate the importance of using these mAbs in various fields of science other than immunology, such as cell biology, biochemistry, microbiology, virology, para-sitology, physiology, genetics, and molecular biology; and also in areas of clinical medicine, such as pathology, hematology, oncology, and infectious disease. The contribution of mAbs to science and clinical medicine was recognized in 1984 by the award of the Nobel Prize for Medicine to Köhler and Milstein. PMID:21337095

  2. Monoclonal antibodies in myeloma.

    PubMed

    Sondergeld, Pia; van de Donk, Niels W C J; Richardson, Paul G; Plesner, Torben

    2015-09-01

    The development of monoclonal antibodies (mAbs) for the treatment of disease goes back to the vision of Paul Ehrlich in the late 19th century; however, the first successful treatment with a mAb was not until 1982, in a lymphoma patient. In multiple myeloma, mAbs are a very recent and exciting addition to the therapeutic armamentarium. The incorporation of mAbs into current treatment strategies is hoped to enable more effective and targeted treatment, resulting in improved outcomes for patients. A number of targets have been identified, including molecules on the surface of the myeloma cell and components of the bone marrow microenvironment. Our review focuses on a small number of promising mAbs directed against molecules on the surface of myeloma cells, including CS1 (elotuzumab), CD38 (daratumumab, SAR650984, MOR03087), CD56 (lorvotuzumab mertansine), and CD138/syndecan-1 (BT062/indatuximab ravtansine). PMID:26452191

  3. [Antithrombotic recombinant antibodies].

    PubMed

    Muzard, Julien; Loyau, Stéphane; Ajzenberg, Nadine; Billiald, Philippe; Jandrot-Perrus, Martine

    2006-01-01

    Coronary syndromes, stroke and other ischaemic arterial diseases are the leading cause of death in the world and will probably remain it at least until 2020. Cardiovascular diseases kill 17 million people each year with an expected increase to 20 million in 2020 and 24 million in 2030. The global impact of recurrence and death during the 6 months following an acute coronary syndrome remains at 8-15% in the present state of medical practice. Acute ischaemic syndromes have a common aetiology that is the formation of a platelet-rich clot at the site of severe coronary stenosis and of eroded atherosclerotic plaques. Therapy consists of medical treatments associating thrombolysis, antiplatelet drugs, and the re-opening of the coronary artery by angioplasty. But these treatments do not prevent morbidity and mortality reaching 15% at 6 months. Finally the treatment of stroke is very limited. There is thus a real clinical need to improve existing treatments and to discover new molecules. Platelet activation is a critical step in ischaemic cardiovascular diseases. This is the reason why antiplatelet drugs are most often prescribed in these cases. Currently, only one recombinant antithrombotic antibody is used in therapy. This is a chimeric Fab, c7E3 or abciximab, which inhibits the final phase of platelet aggregation. Abciximab is prescribed in acute coronary syndromes treated by angioplasty. However, treatment by abciximab can induce severe complications, principally, hemorrages and thrombopenia. Other platelet receptors involved in the earlier steps of platelet activation, such as the phases of contact with and of activation by the subendothelium matrix, have been identified as potential targets for the development of antithrombotic antibodies and are described in this revue. PMID:17652972

  4. Antibody responses to Bordetella bronchiseptica in vaccinated and infected dogs

    PubMed Central

    Ellis, John; Rhodes, Carrie; Lacoste, Stacey; Krakowka, Steven

    2014-01-01

    Bordetella bronchiseptica (Bb) whole cell bacterins have been replaced with acelluar vaccines. We evaluated the response to the acellular Bb vaccines in Bb-seropositive commingled laboratory beagles and client-owned dogs with various lifestyles and vaccination histories. A single parenteral dose of the acellular Bb vaccine resulted in consistent anamnestic IgG, and to a lesser, but notable extent, IgA, Bb-reactive antibody responses in the seropositive beagles. Associated with the increase in antibodies measured by enzyme-linked immunosorbent assay (ELISA) was an increase in the complement (C)-dependent IgG antibody mediated bactericidal effect on Bb in vitro. Antibody responses in client-owned dogs were more variable and were dependent upon the vaccination history and serological evidence of previous Bb exposure. Antibodies from vaccinated dogs recognized several Bb proteins, notably P68 (pertactin) and P220 (fimbrial hemagglutinin), the response to which has been shown to be disease-sparing in Bp infections. These antibody responses were similar to those in experimentally infected dogs and in dogs that had received a widely used whole cell bacterin. PMID:25183893

  5. Naturally acquired antibodies against Clostridium perfringens epsilon toxin in goats.

    PubMed

    Veschi, Josir Laine A; Bruzzone, Octavio A; Losada-Eaton, Daniela M; Dutra, Iveraldo S; Fernandez-Miyakawa, Mariano E

    2008-09-15

    Clostridium perfringens type D-producing epsilon toxin is a common cause of death in sheep and goats worldwide. Although anti-epsilon toxin serum antibodies have been detected in healthy non-vaccinated sheep, the information regarding naturally acquired antibodies in ruminants is scanty. The objective of the present report was to characterize the development of naturally acquired antibodies against C. perfringens epsilon toxin in goats. The levels of anti-epsilon toxin antibodies in blood serum of goat kids from two different herds were examined continuously for 14 months. Goats were not vaccinated against any clostridial disease and received heterologous colostrums from cows that were not vaccinated against any clostridial disease. During the survey one of these flocks suffered an unexpectedly severe C. perfringens type D enterotoxemia outbreak. The results showed that natural acquired antibodies against C. perfringens epsilon toxin can appear as early as 6 weeks in young goats and increase with the age without evidence of clinical disease. The enterotoxemia outbreak was coincident with a significant increase in the level of anti-epsilon toxin antibodies. PMID:18538416

  6. Metrics for antibody therapeutics development.

    PubMed

    Reichert, Janice M

    2010-01-01

    A wide variety of full-size monoclonal antibodies (mAbs) and therapeutics derived from alternative antibody formats can be produced through genetic and biological engineering techniques. These molecules are now filling the preclinical and clinical pipelines of every major pharmaceutical company and many biotechnology firms. Metrics for the development of antibody therapeutics, including averages for the number of candidates entering clinical study and development phase lengths for mAbs approved in the United States, were derived from analysis of a dataset of over 600 therapeutic mAbs that entered clinical study sponsored, at least in part, by commercial firms. The results presented provide an overview of the field and context for the evaluation of on-going and prospective mAb development programs. The expansion of therapeutic antibody use through supplemental marketing approvals and the increase in the study of therapeutics derived from alternative antibody formats are discussed. PMID:20930555

  7. Epstein-Barr virus antibody test

    MedlinePlus

    Epstein-Barr virus antibody test is a blood test to detect antibodies to the Epstein-Barr virus ( EBV ). ... specialist looks for antibodies to the Epstein-Barr virus. In the first stages of an illness, little ...

  8. Antibodies - Office of Cancer Clinical Proteomics Research

    Cancer.gov

    NCI announces the release of monoclonal antipeptide antibodies from rabbit for distribution on the antibody portal. There are 60 recently added monoclonal antibodies, with 56 generated from mouse and 4 generated from rabbit.

  9. Brief Report: Seminal Plasma Anti-HIV Antibodies Trigger Antibody-dependent Cellular Cytotoxicity: Implications for HIV Transmission.

    PubMed

    Parsons, Matthew S; Madhavi, Vijaya; Ana-Sosa-Batiz, Fernanda; Center, Rob J; Wilson, Kim M; Bunupuradah, Torsak; Ruxrungtham, Kiat; Kent, Stephen J

    2016-01-01

    Recent evidence from HIV vaccine trials in humans and non-human primates suggests that nonneutralizing antibody functions, such as antibody-dependent cellular cytotoxicity (ADCC), are an important component of vaccine-mediated protection. Whether anti-HIV ADCC antibodies are present in seminal fluid, however, is not known. We assessed whether anti-HIV antibodies within seminal plasma mediate ADCC and activate natural killer (NK) cells. Using matched blood and seminal plasma samples, we detected anti-HIV IgG within samples from all 11 HIV-infected donors. Furthermore, anti-HIV antibodies within the seminal plasma triggered detectable ADCC in 9 of 11 donors and activated NK cells in 6 of 11 donors. The ability of seminal plasma-derived IgG to activate NK cells in an anti-HIV antibody-dependent manner was enhanced when IgG were enriched and other seminal plasma components were removed. These observations have relevance for understanding natural immunity to HIV infection and provide assistance with HIV vaccine design. PMID:26761269

  10. Cold denaturation of monoclonal antibodies

    PubMed Central

    Lazar, Kristi L; Patapoff, Thomas W

    2010-01-01

    The susceptibility of monoclonal antibodies (mAbs) to undergo cold denaturation remains unexplored. In this study, the phenomenon of cold denaturation was investigated for a mAb, mAb1, through thermodynamic and spectroscopic analyses. tryptophan fluorescence and circular dichroism (CD) spectra were recorded for the guanidine hydrochloride (GuHCl)-induced unfolding of mAb1 at pH 6.3 at temperatures ranging from −5 to 50°C. A three-state unfolding model incorporating the linear extrapolation method was fit to the fluorescence data to obtain an apparent free energy of unfolding, ΔGu, at each temperature. CD studies revealed that mAb1 exhibited polyproline II helical structure at low temperatures and at high GuHCl concentrations. the Gibbs-Helmholtz expression fit to the ΔGu versus temperature data from fluorescence gave a ΔCp of 8.0 kcal mol−1 K−1, a maximum apparent stability of 23.7 kcal mol−1 at 18°C, and an apparent cold denaturation temperature (TCD) of −23°C. ΔGu values for another mAb (mAb2) with a similar framework exhibited less stability at low temperatures, suggesting a depressed protein stability curve and a higher relative TCD. Direct experimental evidence of the susceptibility of mAb1 and mAb2 to undergo cold denaturation in the absence of denaturant was confirmed at pH 2.5. thus, mAbs have a potential to undergo cold denaturation at storage temperatures near −20°C (pH 6.3), and this potential needs to be evaluated independently for individual mAbs. PMID:20093856

  11. Inhibitory and neutral antibodies to Plasmodium falciparum MSP119 form ring structures with their antigen.

    PubMed

    Dekker, Carien; Uthaipibull, Chairat; Calder, Lesley J; Lock, Matthew; Grainger, Munira; Morgan, William D; Dodson, Guy G; Holder, Anthony A

    2004-09-01

    Blood-stage malaria vaccine candidates include surface proteins of the merozoite. Antibodies to these proteins may either block essential steps during invasion or render the merozoite susceptible to phagocytosis or complement-mediated degradation. Structural information on merozoite surface proteins complexed to antibodies provides crucial information for knowledge-based vaccine design. The major merozoite surface protein MSP1 is an abundant surface molecule in Plasmodium falciparum. Only a subset of antibodies against MSP119 inhibits invasion (inhibitory antibodies), whereas other antibodies binding to MSP119 have no effect on invasion (neutral antibodies). Here we report on the complex of MSP119 with both inhibitory monoclonal antibody 12.10 and neutral monoclonal antibody 2F10. The complexes were established using both whole IgG's and Fab fragments, and analysed by dynamic light scattering, electron microscopy and analytical ultra centrifugation. Specific ring structures were formed in the ternary complex with the two antibodies, providing direct evidence of non-overlapping epitopes on MSP119. Mutational studies also indicated that the epitopes of the inhibitory and neutral antibodies are spatially remote. PMID:15279960

  12. Site-targeted mutagenesis for stabilization of recombinant monoclonal antibody expressed in tobacco (Nicotiana tabacum) plants.

    PubMed

    Hehle, Verena K; Paul, Matthew J; Roberts, Victoria A; van Dolleweerd, Craig J; Ma, Julian K-C

    2016-04-01

    This study examined the degradation pattern of a murine IgG1κ monoclonal antibody expressed in and extracted from transformedNicotiana tabacum Gel electrophoresis of leaf extracts revealed a consistent pattern of recombinant immunoglobulin bands, including intact and full-length antibody, as well as smaller antibody fragments. N-terminal sequencing revealed these smaller fragments to be proteolytic cleavage products and identified a limited number of protease-sensitive sites in the antibody light and heavy chain sequences. No strictly conserved target sequence was evident, although the peptide bonds that were susceptible to proteolysis were predominantly and consistently located within or near to the interdomain or solvent-exposed regions in the antibody structure. Amino acids surrounding identified cleavage sites were mutated in an attempt to increase resistance. Different Guy's 13 antibody heavy and light chain mutant combinations were expressed transiently inN. tabacumand demonstrated intensity shifts in the fragmentation pattern, resulting in alterations to the full-length antibody-to-fragment ratio. The work strengthens the understanding of proteolytic cleavage of antibodies expressed in plants and presents a novel approach to stabilize full-length antibody by site-directed mutagenesis.-Hehle, V. K., Paul, M. J., Roberts, V. A., van Dolleweerd, C. J., Ma, J. K.-C. Site-targeted mutagenesis for stabilization of recombinant monoclonal antibody expressed in tobacco (Nicotiana tabacum) plants. PMID:26712217

  13. Site-targeted mutagenesis for stabilization of recombinant monoclonal antibody expressed in tobacco (Nicotiana tabacum) plants

    PubMed Central

    Hehle, Verena K.; Paul, Matthew J.; Roberts, Victoria A.; van Dolleweerd, Craig J.; Ma, Julian K.-C.

    2016-01-01

    This study examined the degradation pattern of a murine IgG1κ monoclonal antibody expressed in and extracted from transformed Nicotiana tabacum. Gel electrophoresis of leaf extracts revealed a consistent pattern of recombinant immunoglobulin bands, including intact and full-length antibody, as well as smaller antibody fragments. N-terminal sequencing revealed these smaller fragments to be proteolytic cleavage products and identified a limited number of protease-sensitive sites in the antibody light and heavy chain sequences. No strictly conserved target sequence was evident, although the peptide bonds that were susceptible to proteolysis were predominantly and consistently located within or near to the interdomain or solvent-exposed regions in the antibody structure. Amino acids surrounding identified cleavage sites were mutated in an attempt to increase resistance. Different Guy’s 13 antibody heavy and light chain mutant combinations were expressed transiently in N. tabacum and demonstrated intensity shifts in the fragmentation pattern, resulting in alterations to the full-length antibody-to-fragment ratio. The work strengthens the understanding of proteolytic cleavage of antibodies expressed in plants and presents a novel approach to stabilize full-length antibody by site-directed mutagenesis.—Hehle, V. K., Paul, M. J., Roberts, V. A., van Dolleweerd, C. J., Ma, J. K.-C. Site-targeted mutagenesis for stabilization of recombinant monoclonal antibody expressed in tobacco (Nicotiana tabacum) plants. PMID:26712217

  14. [Monoclonal antibody for cancer treatment].

    PubMed

    Achiwa, Hiroyuki; Sato, Shigeki; Ueda, Ryuzo

    2002-04-01

    Antibodies have for many decades been viewed as ideal molecules for cancer therapy. Although promising from the start, it has taken much of more than two decades to reach the level of clinical application. Genetic engineering of antibodies; that is novel technologies for chimeric or humanizing monoclonal antibodies, has greatly advanced their utility in molecular targeting therapies, and in the past four years some therapeutic monoclonal antibodies for hematologic malignancies and solid tumors, such as Rituximab for B-cell lymphoma and Trastuzumab for metastatic breast cancer, have provided sufficient efficacy and safety to support regulatory approval from the U.S. Food and Drug Administration. They were subsequently approved by the Japanese Ministry of Health, Labour and Welfare in 2001. Many molecular biological and immunological studies have revealed the targeting properties of the host immune system and the biological mechanism of cancer cells for a more specific anticancer effect. Many clinical trials of monoclonal antibodies as a single agent, or in combination protocol with current standard chemotherapy or immunoconjugates have shown promise in the treatment of specific diseases. Furthermore, novel antibody designs and improved understanding of the mode of action of current antibodies lend great hope to the future of this therapeutic approach. The accumulating results from many basic, clinical and translational studies may lead to more individualized therapeutic strategies using these agent directed at specific genetic and immunologic targets. PMID:11977531

  15. The therapeutic monoclonal antibody market

    PubMed Central

    Ecker, Dawn M; Jones, Susan Dana; Levine, Howard L

    2015-01-01

    Since the commercialization of the first therapeutic monoclonal antibody product in 1986, this class of biopharmaceutical products has grown significantly so that, as of November 10, 2014, forty-seven monoclonal antibody products have been approved in the US or Europe for the treatment of a variety of diseases, and many of these products have also been approved for other global markets. At the current approval rate of ∼ four new products per year, ∼70 monoclonal antibody products will be on the market by 2020, and combined world-wide sales will be nearly $125 billion. PMID:25529996

  16. Reducing heterophilic antibody interference in immunoassays using single chain antibodies

    SciTech Connect

    Baird, Cheryl L.; Tan, Ruimin; Fischer, Christopher J.; Victry, Kristin D.; Zangar, Richard C.; Rodland, Karin D.

    2011-12-15

    Sandwich ELISA microarrays have the potential to simultaneously quantify the levels of multiple diagnostic targets in a biological sample. However, as seen with traditional ELISA diagnostics, heterophilic antibodies (HA) in patient sera have the potential to cause interference in these assays. We demonstrate here that reducing the diagnostic capture antibody to its minimal functional unit, the variable heavy and light domains artificially connected with a short polypeptide linker (scFv), is an effective strategy for reducing the HA assay interference.

  17. Immunotoxicity of monoclonal antibodies

    PubMed Central

    2009-01-01

    Monoclonal antibodies (mAbs) are large molecules intended to bind to specific targets often expressed on the immune system, and to treat various immunopathological conditions. Therefore, mAbs can be considered to have a high potential for immunotoxicity, which is reflected in the clinical experience accumulated on mAbs-induced adverse effects related to immunosuppression, immunostimulation and hypersensitivity (immunogenicity). So far, non clinical immunotoxicity studies have been inadequate to address all safety issues in relation to the possible immunotoxicity of mAbs, because they are fraught with limitations and pitfalls primarily related to the lack of relevant animal species. In addition, clinical studies rarely include validated end-points dedicated to the prediction of immunotoxicity. With the ongoing development of mAbs as novel therapeutic strategies for a wide variety of diseases, efforts should be paid to improve our understanding of mAbs-induced immunotoxic effects and design dedicated strategies to assess their immunological safety, both non clinically and clinically. PMID:20061816

  18. Novel antibody-antibiotic conjugate eliminates intracellular S. aureus.

    PubMed

    Lehar, Sophie M; Pillow, Thomas; Xu, Min; Staben, Leanna; Kajihara, Kimberly K; Vandlen, Richard; DePalatis, Laura; Raab, Helga; Hazenbos, Wouter L; Morisaki, J Hiroshi; Kim, Janice; Park, Summer; Darwish, Martine; Lee, Byoung-Chul; Hernandez, Hilda; Loyet, Kelly M; Lupardus, Patrick; Fong, Rina; Yan, Donghong; Chalouni, Cecile; Luis, Elizabeth; Khalfin, Yana; Plise, Emile; Cheong, Jonathan; Lyssikatos, Joseph P; Strandh, Magnus; Koefoed, Klaus; Andersen, Peter S; Flygare, John A; Wah Tan, Man; Brown, Eric J; Mariathasan, Sanjeev

    2015-11-19

    Staphylococcus aureus is considered to be an extracellular pathogen. However, survival of S. aureus within host cells may provide a reservoir relatively protected from antibiotics, thus enabling long-term colonization of the host and explaining clinical failures and relapses after antibiotic therapy. Here we confirm that intracellular reservoirs of S. aureus in mice comprise a virulent subset of bacteria that can establish infection even in the presence of vancomycin, and we introduce a novel therapeutic that effectively kills intracellular S. aureus. This antibody-antibiotic conjugate consists of an anti-S. aureus antibody conjugated to a highly efficacious antibiotic that is activated only after it is released in the proteolytic environment of the phagolysosome. The antibody-antibiotic conjugate is superior to vancomycin for treatment of bacteraemia and provides direct evidence that intracellular S. aureus represents an important component of invasive infections. PMID:26536114

  19. Functional effects of anticardiolipin antibodies.

    PubMed

    Harris, E N; Pierangeli, S S

    1996-10-01

    The 'lupus anticoagulant' phenomenon is the best documented functional effect of antiphospholipid (aPL) antibodies, occurring either by inhibition of the prothrombinase and/or Factor X activation reactions. Understanding the mechanism by which aPL antibodies inhibit phospholipid dependent coagulation reactions may yield important clues about their 'thrombogenic effects' in vivo. We conducted a series of studies to determine the specificity, diversity, and mechanism by which aPL antibodies inhibit phospholipid dependent reactions. Results showed that purified immunoglobulins with lupus anticoagulant and anti-cardiolipin activities were absorbed by negatively charged phospholipids and both activities were recovered from the phospholipid-antibody precipitate. Purified aPL antibodies inhibited the prothrombinase reaction in a plasma free system in which beta 2-glycoprotein 1 (beta 2-GP1) was absent. Affinity purified aPL antibodies had 25-50 times the inhibitory activity of immunoglobulin preparations. The phospholipid binding proteins, beta 2-GPI and placental anticoagulant protein I (PAP I), independently inhibited the prothrombinase reaction, and when these proteins were combined with aPL, inhibition of the prothrombinase reaction was additive. Antibodies of syphilis had no inhibitory effect, partially accounted for by lack of specificity for phosphotidylserine (PS). Although aPL antibodies inhibited the protein C activation reaction, there was no correlation of these activities with inhibition of the prothrombinase reaction. Together, these results show that aPL exert their effects by interaction with negatively charged phospholipids, in particular phosphotidylserine, but lack of correlation between inhibition of the prothrombinase and protein C activation reactions, suggests that the nature of the coagulation protein is also important. PMID:8902763

  20. Natural monoclonal antibodies and cancer.

    PubMed

    Vollmers, Peter H; Brändlein, Stephanie

    2008-06-01

    Immunity is responsible for recognition and elimination of infectious particles and for removal of cellular waste, modified self structures and transformed cells. Innate or natural immunity acts as a first line defense and is also the link to acquired immunity and memory. By using the human hybridoma technology, a series of monoclonal antibodies and several new tumor-specific targets could be identified. A striking phenomenon of immunity against malignant cells is that all so far isolated tumor-specific antibodies were germ-line coded natural IgM antibodies. And neither in animals nor in humans affinity-maturated tumor-specific IgG antibodies have been detected so far. These IgM's preferentially bind to carbohydrate epitopes on post-transcriptionally modified surface receptors, which are recently patented and preferentially remove malignant cells by inducing apoptosis to avoid inflammatory processes. Our "biology-" or "function-driven" method represents a unique yet powerful approach compared to the typical approaches on screening compounds or antibodies against non-validated targets (mostly differentially expressed). Moreover, the approach creates a competitive patenting strategy of creating proprietary antibodies and validated targets at the same time, which has the potential of further streamlining the discovery of new cancer therapies. PMID:18537750

  1. Antibodies to watch in 2015

    PubMed Central

    Reichert, Janice M

    2015-01-01

    The commercial pipeline of recombinant antibody therapeutics is robust and dynamic. As of early December 2014, a total of 6 such products (vedolizumab, siltuximab, ramucirumab, pembrolizumab, nivolumab, blinatumomab) were granted first marketing approvals in 2014. As discussed in this perspective on antibodies in late-stage development, the outlook for additional approvals, potentially still in 2014 and certainly in 2015, is excellent as marketing applications for 6 antibody therapeutics (secukinumab, evolocumab, mepolizumab, dinutuximab, nivolumab, necitumumab) are undergoing a first regulatory review in the EU or US. Of the 39 novel mAbs currently in Phase 3 studies, a marketing application for one (alirocumab) may be submitted in late 2014, and marketing application submissions for at least 4 (reslizumab, ixekizumab, ocrelizumab, obiltoxaximab) are expected in 2015. Other ‘antibodies to watch’ are those in Phase 3 studies with estimated primary completion dates in late 2014 or 2015, which includes 13 for non-cancer indications (brodalumab, bimagrumab, bococizumab, MABp1, gevokizumab, dupilumab, sirukumab, sarilumab, tildrakizumab, guselkumab, epratuzumab, combination of actoxumab + bezlotoxumab, romosozumab) and 2 (racotumomab and clivatuzumab tetraxetan) undergoing evaluation as treatments for cancer. In addition to the novel antibody therapeutics mentioned, biosimilar infliximab and biosimilar trastuzumab are ‘antibodies to watch’ in 2015 because of their potential for entry into the US market and regulatory review, respectively. PMID:25484055

  2. Antibodies to watch in 2014.

    PubMed

    Reichert, Janice M

    2014-01-01

    Since 2010, mAbs has documented the biopharmaceutical industry's progress in transitioning antibody therapeutics to first Phase 3 clinical studies and regulatory review, and its success at gaining first marketing approvals for antibody-based products. This installment of the "Antibodies to watch" series outlines events anticipated to occur between December 2013 and the end of 2014, including first regulatory actions on marketing applications for vedolizumab, siltuximab, and ramucirumab, as well as the Fc fusion proteins Factor IX-Fc and Factor VIII-Fc; and the submission of first marketing applications for up to five therapeutics (secukinumab, ch14.18, onartuzumab, necitumumab, gevokizumab). Antibody therapeutics in Phase 3 studies are described, with an emphasis on those with study completion dates in 2014, including antibodies targeting interleukin-17a or the interleukin-17a receptor (secukinumab, ixekizumab, brodalumab), proprotein convertase subtilisin/kexin type 9 (alirocumab, evolocumab, bococizumab), and programmed death 1 receptor (lambrolizumab, nivolumab). Five antibodies with US Food and Drug Administration's Breakthrough Therapy designation (obinutuzumab, ofatumumab, lambrolizumab, bimagrumab, daratumumab) are also discussed. PMID:24284914

  3. Novel antibodies as anticancer agents.

    PubMed

    Zafir-Lavie, I; Michaeli, Y; Reiter, Y

    2007-05-28

    In recent years antibodies, whether generated by traditional hybridoma technology or by recombinant DNA strategies, have evolved from Paul Ehrlich's 'magic bullets' to a modern age 'guided missile'. In the recent years of immunologic research, we are witnessing development in the fields of antigen screening and protein engineering in order to create specific anticancer remedies. The developments in the field of recombinant DNA, protein engineering and cancer biology have let us gain insight into many cancer-related mechanisms. Moreover, novel techniques have facilitated tools allowing unique distinction between malignantly transformed cells, and regular ones. This understanding has paved the way for the rational design of a new age of pharmaceuticals: monoclonal antibodies and their fragments. Antibodies can select antigens on both a specific and a high-affinity account, and further implementation of these qualities is used to target cancer cells by specifically identifying exogenous antigens of cancer cell populations. The structure of the antibody provides plasticity resonating from its functional sites. This review will screen some of the many novel antibodies and antibody-based approaches that are being currently developed for clinical applications as the new generation of anticancer agents. PMID:17530025

  4. Antibodies to watch in 2014

    PubMed Central

    Reichert, Janice M

    2014-01-01

    Since 2010, mAbs has documented the biopharmaceutical industry’s progress in transitioning antibody therapeutics to first Phase 3 clinical studies and regulatory review, and its success at gaining first marketing approvals for antibody-based products. This installment of the “Antibodies to watch” series outlines events anticipated to occur between December 2013 and the end of 2014, including first regulatory actions on marketing applications for vedolizumab, siltuximab, and ramucirumab, as well as the Fc fusion proteins Factor IX-Fc and Factor VIII-Fc; and the submission of first marketing applications for up to five therapeutics (secukinumab, ch14.18, onartuzumab, necitumumab, gevokizumab). Antibody therapeutics in Phase 3 studies are described, with an emphasis on those with study completion dates in 2014, including antibodies targeting interleukin-17a or the interleukin-17a receptor (secukinumab, ixekizumab, brodalumab), proprotein convertase subtilisin/kexin type 9 (alirocumab, evolocumab, bococizumab), and programmed death 1 receptor (lambrolizumab, nivolumab). Five antibodies with US Food and Drug Administration’s Breakthrough Therapy designation (obinutuzumab, ofatumumab, lambrolizumab, bimagrumab, daratumumab) are also discussed. PMID:24284914

  5. Avian Diagnostic and Therapeutic Antibodies

    SciTech Connect

    Bradley, David Sherman

    2012-12-31

    A number of infectious agents have the potential of causing significant clinical symptomology and even death, but dispite this, the number of incidence remain below the level that supports producing a vaccine. Therapeutic antibodies provide a viable treatment option for many of these diseases. We proposed that antibodies derived from West Nile Virus (WNV) immunized geese would be able to treat WNV infection in mammals and potential humans. We demonstrated that WNV specific goose antibodies are indeed successful in treating WNV infection both prophylactically and therapeutically in a golden hamster model. We demonstrated that the goose derived antibodies are non-reactogenic, i.e. do not cause an inflammatory response with multiple exposures in mammals. We also developed both a specific pathogen free facility to house the geese during the antibody production phase and a patent-pending purification process to purify the antibodies to greater than 99% purity. Therefore, the success of these study will allow a cost effective rapidly producible therapeutic toward clinical testing with the necessary infrastructure and processes developed and in place.

  6. Cancer therapy with radiolabeled and drug/toxin-conjugated antibodies.

    PubMed

    Govindan, Serengulam V; Griffiths, Gary L; Hansen, Hans J; Horak, Ivan D; Goldenberg, David M

    2005-08-01

    Radioimmunotherapy and antibody-directed chemotherapy have emerged as cancer treatment modalities with the regulatory approval of products for non-Hodgkin's lymphoma and acute myeloid leukemia. Antibody-toxin therapy is likewise on the verge of clinical fruition. Accumulating evidence suggests that radioimmunotherapy may have the best impact in minimal-disease and adjuvant settings, especially with radioresistant solid tumors. For the latter, ongoing efforts in 'pretargeting' to increase deliverable tumor radiation dose, combination therapies, and locoregional applications are also of importance. Antibody-drug conjugates have the potential to increase the therapeutic index of chemotherapy by minimizing systemic toxicity and improving tumor targeting. The design of optimal drug conjugates in this regard is predicated upon the proper choice of the target antigen, the cleavable-linker, and the drug. In respect of antibody-toxin conjugates, considerable progress has been made in chemical and recombinant immunotoxin designs, and in the advancement of many products to clinical trials. Continued development of antibody-directed therapies should expand the options available for the management of cancer. PMID:16029057

  7. Alternative downstream processes for production of antibodies and antibody fragments.

    PubMed

    Arakawa, Tsutomu; Tsumoto, Kouhei; Ejima, Daisuke

    2014-11-01

    Protein-A or Protein-L affinity chromatography and virus inactivation are key processes for the manufacturing of therapeutic antibodies and antibody fragments. These two processes often involve exposure of therapeutic proteins to denaturing low pH conditions. Antibodies have been shown to undergo conformational changes at low pH, which can lead to irreversible damages on the final product. Here, we review alternative downstream approaches that can reduce the degree of low pH exposure and consequently damaged product. We and others have been developing technologies that minimize or eliminate such low pH processes. We here cover facilitated elution of antibodies using arginine in Protein-A and Protein-G affinity chromatography, a more positively charged amidated Protein-A, two Protein-A mimetics (MEP and Mabsorbent), mixed-mode and steric exclusion chromatography, and finally enhanced virus inactivation by solvents containing arginine. This article is part of a Special Issue entitled: Recent advances in molecular engineering of antibody. PMID:24859179

  8. Macrophage Internal HIV-1 Is Protected from Neutralizing Antibodies

    PubMed Central

    Koppensteiner, Herwig; Banning, Carina; Schneider, Carola; Hohenberg, Heinrich

    2012-01-01

    In macrophages, HIV-1 accumulates in intracellular vesicles designated virus-containing compartments (VCCs). These might play an important role in the constitution of macrophages as viral reservoirs and allow HIV-1 to evade the immune system by sequestration in an internal niche, which is difficult to access from the exterior. However, until now, evidence of whether internal virus accumulations are protected from the host's humoral immune response is still lacking. In order to be able to study the formation and antibody accessibility of VCCs, we generated HIV-1 with green fluorescent protein (GFP)-tagged Gag replicating in primary macrophages. Live-cell observations revealed faint initial cytosolic Gag expression and subsequent large intracellular Gag accumulations which stayed stable over days. Taking advantage of the opportunity to study the accessibility of intracellular VCCs via the cell surface, we demonstrate that macrophage internal HIV-1-containing compartments cannot be targeted by neutralizing antibodies. Furthermore, HIV-1 was efficiently transferred from antibody-treated macrophages to T cells. Three-dimensional reconstruction of electron microscopic slices revealed that Gag accumulations correspond to viral particles within enclosed compartments and convoluted membranes. Thus, although some VCCs were connected to the plasma membrane, the complex membrane architecture of the HIV-1-containing compartment might shield viral particles from neutralizing antibodies. In sum, our study provides evidence that HIV-1 is sequestered into a macrophage internal membranous web, posing an obstacle for the elimination of this viral reservoir. PMID:22205742

  9. Antibody-dependent cellular cytotoxicity and skin disease

    SciTech Connect

    Norris, D.A.; Lee, L.A.

    1985-07-01

    Antibody dependent cellular cytotoxicity (ADCC) is a recently described mechanism of immunologic lysis in which cellular targets sensitized by specific antibodies are efficiently and selectively lysed by Fc receptor (FcR) bearing nonspecific effectors. Immunoglobulins of various classes (IgG, IgM, IgA, IgE) and various cellular effectors (large granular lymphocytes, monocyte/macrophages, T lymphocytes, neutrophils, and eosinophils) can induce ADCC in vitro, and the importance of ADCC in vivo is being tested experimentally in resistance to viral, bacterial, and parasitic infection, in tumor surveillance, in allograft rejection, and in inflammatory diseases. There is much indirect evidence that ADCC may be the mechanism of damage of different cellular targets in skin diseases, but the best direct evidence concerns immunologic keratinocyte damage, especially in cutaneous lupus erythematosus (LE). The authors have shown that keratinocytes of several species are highly susceptible to lymphocyte and monocyte-mediated ADCC, but not to neutrophil or eosinophil ADCC in vitro using two different cytotoxicity assays. In contrast, complement was a relatively ineffective mediator of lysis of metabolically intact keratinocyte targets. Patients with certain cutaneous lupus syndromes have serum antibodies capable of inducing monocyte and lymphocyte ADCC of targets coated with extractable nuclear antigens. The authors have shown that these antigens apparently move to the cell membrane of keratinocytes in vitro following ultraviolet irradiation. In an animal model, they have shown that antibodies to SSA/Ro bind to human keratinocytes in vivo, especially after ultraviolet irradiation.

  10. Biological Activities of Rabbit Immunoglobulin M and Immunoglobulin G Antibodies to Pseudomonas aeruginosa

    PubMed Central

    Bjornson, Ann B.; Michael, J. Gabriel

    1970-01-01

    Immunoglobulin (Ig)M and IgG antibodies, prepared in the rabbit against the protective antigen of Pseudomonas aeruginosa P4, were compared as to their biological activities in vitro and in vivo. In vitro biological activities of these antibodies were determined by passive hemagglutination, bactericidal, and opsonophagocytic tests. Increased effectiveness of IgM over IgG on a molar basis was demonstrated in all of these tests. However, in mouse protection tests, in which the purified globulins were injected intraperitoneally 4 hr prior to challenge with P. aeruginosa suspended in hog gastric mucin, IgM anticapsular antibody was found to be less effective than IgG antibody. The exact mechanism whereby IgG antibody exerts more protective ability than IgM antibody is still unknown. We present evidence to suggest that the difference in activity between the two classes of antibody is due to the ability of the IgG antibody to enter the bloodstream more rapidly than the IgM antibody and also to the ability of IgG to diffuse rapidly through the tissues of the organs. PMID:16557861

  11. Autoantibodies: Focus on anti-DNA antibodies.

    PubMed

    Almqvist, Nina; Winkler, Thomas H; Mårtensson, Inga-Lill

    2011-01-01

    Ever since the days of Ehrlich and the birth of humoral immunity, self-reactivity or 'horror autotoxicus' as referred to by Paul Ehrlich, has been of great concern. For instance, in patients with the autoimmune disease systemic lupus erythematosus (SLE), anti-nuclear and anti-DNA antibodies have been recognized for many years. Despite this, the exact mechanism as to how the immune system fails to protect the individual and allows these autoantibodies to develop in this and other systemic autoimmune diseases remains uncertain. So how can we explain their presence? Evidence suggests that B cells expressing autoreactive antibodies do not normally arise but rather undergo negative selection as they develop. In light of this, it might seem contradictory that not all autoreactive B cell clones are eliminated, although this may not even be the intention since autoantibodies are also found in healthy individuals and may even protect from autoimmunity. Here, we will discuss autoantibodies, in particular those recognizing DNA, with regard to their reactivity and their potentially pathogenic or protective properties. PMID:21776330

  12. Antibody-Mediated Autoimmune Encephalopathies and Immunotherapies.

    PubMed

    Gastaldi, Matteo; Thouin, Anaïs; Vincent, Angela

    2016-01-01

    Over the last 15 years it has become clear that rare but highly recognizable diseases of the central nervous system (CNS), including newly identified forms of limbic encephalitis and other encephalopathies, are likely to be mediated by antibodies (Abs) to CNS proteins. The Abs are directed against membrane receptors and ion channel-associated proteins that are expressed on the surface of neurons in the CNS, such as N-methyl D-aspartate receptors and leucine-rich, glioma inactivated 1 protein and contactin-associated protein like 2, that are associated with voltage-gated potassium channels. The diseases are not invariably cancer-related and are therefore different from the classical paraneoplastic neurological diseases that are associated with, but not caused by, Abs to intracellular proteins. Most importantly, the new antibody-associated diseases almost invariably respond to immunotherapies with considerable and sometimes complete recovery, and there is convincing evidence of their pathogenicity in the relatively limited studies performed so far. Treatments include first-line steroids, intravenous immunoglobulins, and plasma exchange, and second-line rituximab and cyclophosphamide, followed in many cases by steroid-sparing agents in the long-term. This review focuses mainly on N-methyl D-aspartate receptor- and voltage-gated potassium channel complex-related Abs in adults, the clinical phenotypes, and treatment responses. Pediatric cases are referred to but not reviewed in detail. As there have been very few prospective studies, the conclusions regarding immunotherapies are based on retrospective studies. PMID:26692392

  13. MERS-CoV Antibodies in Humans, Africa, 2013-2014.

    PubMed

    Liljander, Anne; Meyer, Benjamin; Jores, Joerg; Müller, Marcel A; Lattwein, Erik; Njeru, Ian; Bett, Bernard; Drosten, Christian; Corman, Victor Max

    2016-06-01

    Dromedaries in Africa and elsewhere carry the Middle East respiratory syndrome coronavirus (MERS-CoV). To search for evidence of autochthonous MERS-CoV infection in humans, we tested archived serum from livestock handlers in Kenya for MERS-CoV antibodies. Serologic evidence of infection was confirmed for 2 persons sampled in 2013 and 2014. PMID:27071076

  14. MERS-CoV Antibodies in Humans, Africa, 2013–2014

    PubMed Central

    Liljander, Anne; Meyer, Benjamin; Jores, Joerg; Müller, Marcel A.; Lattwein, Erik; Njeru, Ian; Bett, Bernard; Corman, Victor Max

    2016-01-01

    Dromedaries in Africa and elsewhere carry the Middle East respiratory syndrome coronavirus (MERS-CoV). To search for evidence of autochthonous MERS-CoV infection in humans, we tested archived serum from livestock handlers in Kenya for MERS-CoV antibodies. Serologic evidence of infection was confirmed for 2 persons sampled in 2013 and 2014. PMID:27071076

  15. Investigating the structural biofunctionality of antibodies conjugated to magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Occhipinti, Emanuela; Verderio, Paolo; Natalello, Antonino; Galbiati, Elisabetta; Colombo, Miriam; Mazzucchelli, Serena; Salvadè, Agnese; Tortora, Paolo; Doglia, Silvia Maria; Prosperi, Davide

    2011-02-01

    We present the synthesis of trastuzumab-functionalized pegylated iron oxide nanoparticles and provide an FTIR-based approach to gain a direct evidence of the actual conservation of the native structure of conjugated antibody. Their target-selectivity to specific cancer cell receptors has been also assessed.We present the synthesis of trastuzumab-functionalized pegylated iron oxide nanoparticles and provide an FTIR-based approach to gain a direct evidence of the actual conservation of the native structure of conjugated antibody. Their target-selectivity to specific cancer cell receptors has been also assessed. Electronic supplementary information (ESI) available: Experimental details, TEM images, DLS and relaxivity plots, additional FT-IR spectra and analyses. See DOI: 10.1039/c0nr00436g

  16. Transfusion significance of LWa allo-antibodies.

    PubMed

    Napier, J A; Rowe, G P

    1987-01-01

    An example of anti-LWa, arising as a complication during a RhD immunization programme, has been studied for evidence of its likely in vivo haemolytic properties. In vitro testing of the anti-LWa showed it to be largely IgG1 acting by the antiglobulin technique. Results of antibody-dependent cellular cytotoxicity and macrophage phagocytic assays were both negative. However, 99mTc-labelled Lw(a+) donor cells showed a slight reduction in t1/2 (18 h) compared with the normal survival of autologous cells. Despite this observation, and bearing in mind the difficulties of interpreting apparently accelerated destruction of small serologically incompatible red cells, it was concluded that the presence of this example of anti-LWa should not be a bar to urgent transfusion. PMID:3125687

  17. Antibodies: an alternative for antibiotics?

    PubMed

    Berghman, L R; Abi-Ghanem, D; Waghela, S D; Ricke, S C

    2005-04-01

    In 1967, the success of vaccination programs, combined with the seemingly unstoppable triumph of antibiotics, prompted the US Surgeon General to declare that "it was time to close the books on infectious diseases." We now know that the prediction was overly optimistic and that the fight against infectious diseases is here to stay. During the last 20 yr, infectious diseases have indeed made a staggering comeback for a variety of reasons, including resistance against existing antibiotics. As a consequence, several alternatives to antibiotics are currently being considered or reconsidered. Passive immunization (i.e., the administration of more or less pathogen-specific antibodies to the patient) prior to or after exposure to the disease-causing agent is one of those alternative strategies that was almost entirely abandoned with the introduction of chemical antibiotics but that is now gaining interest again. This review will discuss the early successes and limitations of passive immunization, formerly referred to as "serum therapy," the current use of antibody administration for prophylaxis or treatment of infectious diseases in agriculture, and, finally, recent developments in the field of antibody engineering and "molecular farming" of antibodies in various expression systems. Especially the potential of producing therapeutic antibodies in crops that are routine dietary components of farm animals, such as corn and soy beans, seems to hold promise for future application in the fight against infectious diseases. PMID:15844826

  18. Antibodies to watch in 2016.

    PubMed

    Reichert, Janice M

    2016-01-01

    The number of novel antibody therapeutics that received first marketing approvals in 2015 met expectations, with 6 (alirocumab (Praluent®), evolocumab (Repatha®), daratumumab (Darzalex®), dinutuximab (Unituxin®), idarucizumab (Praxbind®), mepolizumab (Nucala®)) granted first approvals as of mid-November*. Seven novel antibody therapeutics (begelomab, brodalumab, elotuzumab, ixekizumab, necitumumab, obiltoxaximab, reslizumab) are in regulatory review, and thus a similar number, if not more, are projected to gain first approvals in 2016. Commercial late-stage antibody therapeutics development exceeded expectations by increasing from 39 candidates in Phase 3 studies as of late 2014 to 53 as of late 2015. Of the 53 candidates, transitions to regulatory review by the end of 2016 are projected for 8 (atezolizumab, benralizumab, bimagrumab, durvalumab, inotuzumab ozogamicin, lebrikizumab, ocrelizumab, tremelimumab). Other "antibodies to watch" include 15 candidates (bavituximab, bococizumab, dupilumab, fasinumab, fulranumab, gevokizumab, guselkumab, ibalizumab, LY2951742, onartuzumab, REGN2222, roledumab, romosozumab, sirukumab, Xilonix) undergoing evaluation in Phase 3 studies that have estimated primary completion dates in 2016. As evidenced by the antibody therapeutics discussed in this perspective, the biopharmaceutical industry has a highly active late-stage clinical pipeline that may deliver numerous new products to the global market in the near future. *See Note added in proof for updates through December 31, 2015. PMID:26651519

  19. Antibody persistence and T-cell balance: Two key factors confronting HIV vaccine development

    PubMed Central

    Lewis, George K.; DeVico, Anthony L.; Gallo, Robert C.

    2014-01-01

    The quest for a prophylactic AIDS vaccine is ongoing, but it is now clear that the successful vaccine must elicit protective antibody responses. Accordingly, intense efforts are underway to identify immunogens that elicit these responses. Regardless of the mechanism of antibody-mediated protection, be it neutralization, Fc-mediated effector function, or both, antibody persistence and appropriate T-cell help are significant problems confronting the development of a successful AIDS vaccine. Here, we discuss the evidence illustrating the poor persistence of antibody responses to Env, the envelope glycoprotein of HIV-1, and the related problem of CD4+ T-cell responses that compromise vaccine efficacy by creating excess cellular targets of HIV-1 infection. Finally, we propose solutions to both problems that are applicable to all Env-based AIDS vaccines regardless of the mechanism of antibody-mediated protection. PMID:25349379

  20. Enhancing Blockade of Plasmodium falciparum Erythrocyte Invasion: Assessing Combinations of Antibodies against PfRH5 and Other Merozoite Antigens

    PubMed Central

    Miura, Kazutoyo; Illingworth, Joseph J.; Choudhary, Prateek; Murungi, Linda M.; Furze, Julie M.; Diouf, Ababacar; Miotto, Olivo; Crosnier, Cécile; Wright, Gavin J.; Kwiatkowski, Dominic P.; Fairhurst, Rick M.; Long, Carole A.; Draper, Simon J.

    2012-01-01

    No vaccine has yet proven effective against the blood-stages of Plasmodium falciparum, which cause the symptoms and severe manifestations of malaria. We recently found that PfRH5, a P. falciparum-specific protein expressed in merozoites, is efficiently targeted by broadly-neutralizing, vaccine-induced antibodies. Here we show that antibodies against PfRH5 efficiently inhibit the in vitro growth of short-term-adapted parasite isolates from Cambodia, and that the EC50 values of antigen-specific antibodies against PfRH5 are lower than those against PfAMA1. Since antibody responses elicited by multiple antigens are speculated to improve the efficacy of blood-stage vaccines, we conducted detailed assessments of parasite growth inhibition by antibodies against PfRH5 in combination with antibodies against seven other merozoite antigens. We found that antibodies against PfRH5 act synergistically with antibodies against certain other merozoite antigens, most notably with antibodies against other erythrocyte-binding antigens such as PfRH4, to inhibit the growth of a homologous P. falciparum clone. A combination of antibodies against PfRH4 and basigin, the erythrocyte receptor for PfRH5, also potently inhibited parasite growth. This methodology provides the first quantitative evidence that polyclonal vaccine-induced antibodies can act synergistically against P. falciparum antigens and should help to guide the rational development of future multi-antigen vaccines. PMID:23144611

  1. Antisperm antibodies and in vitro fertilization.

    PubMed

    Janssen, H J; Bastiaans, B A; Goverde, H J; Hollanders, H M; Wetzels, A A; Schellekens, L A

    1992-08-01

    The purpose of this study was to investigate the influence of antisperm antibodies in the male, the female, or both partners on the outcome of in vitro fertilization treatment. The results in terms of ongoing pregnancies in the male and female antibody-positive group were the same as in the antibody-negative group. In the double antibody-positive group two of the three patients became pregnant. When high levels of antisperm antibodies were present on the spermatozoa, the fertilization rate was significantly reduced. In the female positive group no clear relationship between the antibody titer and the fertilization percentage could be detected. Abnormal semen quality was responsible for a much lower fertilization rate than the presence of antibodies. The conclusion of this study is that in vitro fertilization provides an equal change of conception in couples with antisperm antibodies in comparison with couples with no antibodies if the other semen parameters are normal. PMID:1472812

  2. Communication: Antibody stability and behavior on surfaces

    NASA Astrophysics Data System (ADS)

    Bush, Derek B.; Knotts, Thomas A.

    2015-08-01

    Antibody microarrays have the potential to revolutionize molecular detection in scientific, medical, and other biosensor applications, but their current use is limited because of poor reliability. It is hypothesized that one reason for their poor performance results from strong antibody-surface interactions that destabilize the antibody structure and create steric interference for antigen recognition. Using a recently developed coarse-grain protein-surface model that has been parameterized against experimental data, antibody-surface interactions for two antibody orientations on two types of surfaces have been investigated. The results show that regardless of attachment geometry, antibodies tend to collapse onto hydrophobic surfaces and exhibit lower overall stability compared to antibodies on hydrophilic surfaces or in bulk solution. The results provide an unprecedented view into the dynamics of antibodies on surfaces and offer new insights into the poor performance exhibited by current antibody microarrays.

  3. Communication: Antibody stability and behavior on surfaces.

    PubMed

    Bush, Derek B; Knotts, Thomas A

    2015-08-14

    Antibody microarrays have the potential to revolutionize molecular detection in scientific, medical, and other biosensor applications, but their current use is limited because of poor reliability. It is hypothesized that one reason for their poor performance results from strong antibody-surface interactions that destabilize the antibody structure and create steric interference for antigen recognition. Using a recently developed coarse-grain protein-surface model that has been parameterized against experimental data, antibody-surface interactions for two antibody orientations on two types of surfaces have been investigated. The results show that regardless of attachment geometry, antibodies tend to collapse onto hydrophobic surfaces and exhibit lower overall stability compared to antibodies on hydrophilic surfaces or in bulk solution. The results provide an unprecedented view into the dynamics of antibodies on surfaces and offer new insights into the poor performance exhibited by current antibody microarrays. PMID:26277119

  4. Uses of monoclonal antibody 8H9

    DOEpatents

    Cheung, Nai-Kong V.

    2013-04-09

    This invention provides a composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a suitable carrier. This invention provides a pharmaceutical composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a pharmaceutically acceptable carrier. This invention also provides an antibody other than the monoclonal antibody 8H9 comprising the complementary determining regions of monoclonal antibody 8H9 or a derivative thereof, capable of binding to the same antigen as the monoclonal antibody 8H9. This invention provides a substance capable of competitively inhibiting the binding of monoclonal antibody 8H9. This invention also provides an isolated scFv of monoclonal antibody 8H9 or a derivative thereof. This invention also provides the 8H9 antigen. This invention also provides different uses of the monoclonal antibody 8H9 or its derivative.

  5. Uses of monoclonal antibody 8H9

    DOEpatents

    Cheung, Nai-Kong V.

    2010-06-22

    This invention provides a composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a suitable carrier. This invention provides a pharmaceutical composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a pharmaceutically acceptable carrier. This invention also provides an antibody other than the monoclonal antibody 8H9 comprising the complementary determining regions of monoclonal antibody 8H9 or a derivative thereof, capable of binding to the same antigen as the monoclonal antibody 8H9. This invention provides a substance capable of competitively inhibiting the binding of monoclonal antibody 8H9. This invention also provides an isolated scFv of monoclonal antibody 8H9 or a derivative thereof. This invention also provides the 8H9 antigen. This invention also provides different uses of the monoclonal antibody 8H9 or its derivative.

  6. Remembering antibodies coming of age.

    PubMed

    Melchers, Fritz

    2016-01-01

    Fifty years ago, Norbert Hilschmann discovered that antibodies have variable immunoglobulin domains to bind antigens, and constant domains to carry out effector functions in the immune system. Just as this happened, the author of this perspective entered the field of immunology. Ten years later, the genetic basis of antibody variability was discovered by Susumu Tonegawa and his colleagues at the Basel Institute for Immunology, where the author had become a scientific member. At the same time, Georges Köhler, a former graduate student of the author's at the Basel Institute, invented with Cesar Milstein at the Laboratory of Molecular Biology in Cambridge, England, the method to produce monoclonal antibodies. The author describes here his memories connected to these three monumental, paradigm-changing discoveries, which he observed in close proximity. PMID:27144253

  7. Molecular-specific urokinase antibodies

    NASA Technical Reports Server (NTRS)

    Atassi, M. Zouhair (Inventor); Morrison, Dennis R. (Inventor)

    2009-01-01

    Antibodies have been developed against the different molecular forms of urokinase using synthetic peptides as immunogens. The peptides were synthesized specifically to represent those regions of the urokinase molecules which are exposed in the three-dimensional configuration of the molecule and are uniquely homologous to urokinase. Antibodies are directed against the lysine 158-isoleucine 159 peptide bond which is cleaved during activation from the single-chain (ScuPA) form to the bioactive double chain (54 KDa and 33 KDa) forms of urokinase and against the lysine 135 lysine 136 bond that is cleaved in the process of removing the alpha-chain from the 54 KDa form to produce the 33 KDa form of urokinase. These antibodies enable the direct measurement of the different molecular forms of urokinase from small samples of conditioned medium harvested from cell cultures.

  8. Antibodies to watch in 2013

    PubMed Central

    Reichert, Janice M

    2013-01-01

    The transitions of antibody therapeutics to late-stage clinical development, regulatory review and the market are proceeding at a rapid pace in 2013. Since late 2012, two monoclonal antibody (mAb) therapeutics (itolizumab, trastuzumab emtansine) received their first approvals, first marketing applications for three mAbs (vedolizumab, ramucirumab, obinutuzumab) were submitted to regulatory agencies, and five mAbs (brodalumab, MABp1, moxetumomab pasudotox, tildrakizumab, rilotumumab) entered their first Phase 3 studies. The current total of commercially-sponsored antibody therapeutics undergoing evaluation in late-stage studies is 30. Recently announced study results for farletuzumab, naptumomab estafenatox, and tabalumab indicate that clinical endpoints were not met in some Phase 3 studies of these product candidates. PMID:23727858

  9. Electron Microscopic Studies of the Antigen-Antibody Complex

    PubMed Central

    Easty, G. C.; Mercer, E. H.

    1958-01-01

    Electron micrographs of the ferritin antibody (rabbit) and ferritin (horse) complex have been obtained. The high iron content of the ferritin molecule (23 per cent Fe) allows its molecules to be recognized within the particles of precipitate. Three methods of visualizing the molecular distribution have been developed: (a) small particles of the precipitated complex have been dried on to electron microscope grids and either examined directly or first shadowed with metal and then examined, (b) the precipitate has been centrifuged to a plug which was embedded and thin sections cut from it for examination, (c) the bands formed by allowing antibody and antigen to diffuse together in agar gels have been fixed, embedded and sectioned. All methods have yielded pictures of the distribution of the ferritin within the complex which are broadly similar to what might have been expected from a somewhat irregular lattice as pictured in the Marrack-Heidelberger Lattice Theory. The antibody molecules are not clearly defined but appear as a halo of low density enveloping the ferritin clusters. The distance, centre to centre, between the ferritin molecules is variable, but is, on the average, in the range 200–400 Å. This is greater than the ferritin-ferritin contact distance (100 Å) and is thought to mean that the ferritin molecules are bridged by antibody molecules as pictured in the Lattice Theory. The bands produced in the gel-diffusion test contain islands of ferritin-antibody complex. When equivalent concentrations of reagents are used a single band of precipitate is formed. When excess of either antigen or antibody is used multiple bands of precipitate are formed which contain islands of ferritin antibody complex indistinguishable from those formed in the single band at equivalent concentrations, providing direct evidence for the formation of multiple bands from a single antigen. Ferritin-ferritin contacts have been observed within the complex. Under all the conditions of

  10. Antinuclear antibodies in domestic animals.

    PubMed

    Gershwin, Laurel J

    2005-06-01

    Antinuclear antibodies in domestic animal species have been commonly detected for many years, with the greatest frequency occurring in dogs as well as horses and cats. Most commonly, the assay used in diagnostic laboratories is indirect immunofluorescence on HEP-2 cells, similar to that used in human medicine, but with the exception that species-specific antiglobulin reagents are used instead of antihuman immunoglobulin. To a lesser extent, the Crithidia luciliae test for antibodies to double-stranded DNA has been used. Several research groups have used other assays. PMID:16014553

  11. Antinuclear antibodies and anticytoplasmic antibodies in bronchial asthma.

    PubMed

    Menon, P; Menon, V; Hilman, B C; Wolf, R; Bairnsfather, L

    1989-12-01

    The presence of antinuclear antibodies and anticytoplasmic antibodies was evaluated in the sera of 50 patients with bronchial asthma and 35 matched control subjects with miscellaneous medical diseases with the use of an indirect immunofluorescent assay with HEp-2 cells as substrate. The results were compared to age, sex, atopic status, dose, and duration of the antiasthmatic medication, immunotherapy, severity of the disease, and presence or absence of myalgia. The patients had mild to moderate asthma. The incidence of fluorescent anticytoplasmic antibodies (FACA) in the sera of patients with asthma was statistically significant (p = 0.02) in comparison to FACA in the sera of the control subjects. The combined incidence of fluorescent antinuclear antibodies (FANA) and FACA was found to be significantly higher among atopic subjects with asthma (p = 0.03) and the subjects with asthma and with myalgia (p less than 0.05). The 20% incidence of FACA in this group of subjects with asthma was significantly greater (p less than 0.0001) than the reported 2.7% incidence of FACA in a group of patients with various rheumatologic diseases. Variables, such as dose and duration of antiasthma medications and immunotherapy did not appear to influence the presence of FANA and FACA in their sera. The significance of positive FANA and FACA in this group of subjects with asthma is not known and needs to be evaluated by long-term studies. PMID:2689497

  12. Antibody profiling sensitivity through increased reporter antibody layering

    DOEpatents

    Apel, William A.; Thompson, Vicki S

    2010-04-13

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  13. Antibody profiling sensitivity through increased reporter antibody layering

    DOEpatents

    Apel, William A.; Thompson, Vicki S.

    2013-02-26

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  14. Monoclonal Antibodies for the Treatment of Cancer

    PubMed Central

    Shuptrine, Casey; Surana, Rishi; Weiner, Louis M.

    2012-01-01

    Over the past decade, the clinical utility of monoclonal antibodies has been realized and antibodies are now a mainstay for the treatment of cancer. Antibodies have the unique capacity to target and kill tumor cells while simultaneously activating immune effectors to kill tumor cells through the complement cascade or antibody-dependent cellular cytotoxicity (ADCC). This multifaceted mechanism of action combined with target specificity underlies the capacity of antibodies to elicit anti-tumor responses while minimizing the frequency and magnitude of adverse events. This review will focus on mechanisms of action, clinical applications and putative mechanisms of resistance to monoclonal antibody therapy in the context of cancer. PMID:22245472

  15. Antibody response and antibody affinity maturation in cats with experimental proliferative immune complex glomerulonephritis.

    PubMed

    Bishop, S A; Bailey, M; Lucke, V M; Stokes, C R

    1992-07-01

    alteration in IgM affinity occurred at a late stage, as serum IgM levels increased, in cats which progressed to develop GN. These findings suggested that an increase in both serum IgG and IgM anti-HSA values, in particular IgM, was associated with the development of a more severe immune complex renal disease in these cats. Although there was no evidence that differences in the average affinity of either the IgG or IgM antibody populations for HSA, were associated with the development of disease, the increase in IgM values was also accompanied by a concomitant alteration in IgM affinity for antigen.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1430350

  16. Three major uncertainties in the antibody therapy of cancer

    PubMed Central

    Stevenson, George T.

    2014-01-01

    Antibodies against surface molecules of human tumors are now frequently administered in combination with strong chemotherapy, increasing therapeutic efficacy but making the task of elucidating immunological events more difficult. Experiments on genetically manipulated mice indicate that antibody efficacy is greatest when IgG antibody coating tumor cells is engaged by the Fcγ-receptors of effector cells, chiefly the monocyte/macrophage lineage. Evidence suggests lesser roles for NK cells, neutrophils, receptor-mediated cytotoxicity and complement-mediated cytotoxicity. The classical mode of killing employed by macrophages is phagocytosis, but much has to be learned about optimally activating macrophages for this task, and about any other modes of cytotoxicity used. There is renewed interest in antigenic modulation, which implies removal of therapeutic antibody linked with antigen from target-cell surfaces. It is now apparent that this removal of immune complexes can be achieved either by internalization by the target cell, or by transfer of the complexes to another cell by trogocytosis. In trials, anti-idiotype antibodies surprisingly proved therapeutically more effective than anti-CD20, despite anti-idiotype being more effectively removed from target-cell surfaces by antigenic modulation. This anomalous result might reflect the fact that persistence of anti-CD20 immune complexes in large amounts induces serious effector modulation, which paralyzes macrophage attacks on antibody-coated cells. The case for effector modulation is argued by analogy with the therapeutic suppression of autoimmune inflammation by effector modulation, achieved by infusion either of normal IgG in large amounts, or of anti-red cell IgG in relatively small amounts. PMID:25271313

  17. Anti-survivin antibody responses in lung cancer.

    PubMed

    Karanikas, Vaios; Khalil, Sanaa; Kerenidi, Theodora; Gourgoulianis, Konstantinos I; Germenis, Anastasios E

    2009-09-18

    Existing evidence regarding spontaneous anti-survivin humoral responses in lung cancer is inconclusive. Moreover, despite that cancer cell death elicited by radiotherapy and some chemotherapeutic agents seems to be immunogenic, information about the possible effect of treatment on these responses, is lacking. Serum samples from 33 small cell lung cancer (SCLC) and 117 non-small cell lung cancer (NSCLC) patients upon diagnosis, and from 100 controls, were tested by ELISA for anti-survivin antibodies. Cutoff was set to the mean+2SD of controls. 7.7% of NSCLC, none of the SCLC patients and 2% of the controls appeared with elevated antibody levels (OR 3.6, 95% CI 0.7-17.3 for NSCLC, OR 0.6, 95% CI 0.03-12.6 for SCLC). Measurement of antibodies in 76 NSCLC patients post therapies and during their follow-up, revealed that in 12 NSCLC patients the antibody levels increased up to 2-38 times, and in seven others, they decreased by 2-8 times. No significant correlation was uncovered between either the antibody levels upon diagnosis or their changes post therapies and during follow-up, and any clinicopathological parameter, their response to therapy and survival. Survivin does not induce considerable humoral responses in lung cancer. Potentially, however, strong anti-survivin antibody responses can be elicited during the post therapy and follow-up of the patients, whose clinical significance remains to be elucidated. These findings, together with our previous data concerning survivin expression and the related cytolytic T cell responses in lung cancer, signify a high tolerogenic potential of this tumor-associated antigen. PMID:19380192

  18. The mechanism of hepatic uptake of a radiolabelled monoclonal antibody.

    PubMed

    Boyle, C C; Paine, A J; Mather, S J

    1992-04-01

    Clinical and experimental scintigraphic studies have found that radiolabelled antibodies are not only taken up by tumour(s) but also by normal liver. The accumulation of radionuclides in this organ poses a major problem to the use of radiolabelled antibodies as diagnostic and therapeutic tools. In an attempt to understand the mechanism of hepatic uptake and clearance of radiolabelled antibodies, the intrahepatic biodistribution of an 111In-labelled MAb (HMFG1), was determined following i.v. administration to normal male rats. Two hours after administration the liver contained 15% of the injected dose, with most of the remaining radioactivity in the blood. The hepatic burden of the 111In MAb remained constant over the next 72 hr in the face of decreasing blood levels of radioactivity as well as its urinary and faecal excretion. At 2 and 72 hr after injection, 50% and 10% respectively of the hepatic radiolabel was due to blood borne antibody. Following a collagenase-cell isolation procedure, only 23% of the amount remaining in the liver at 2 hr was found to be cell-associated; 66% was lost during the cell isolation and purification procedure. Cellular uptake increased with time so that, by 72 hr after administration, 58% was cell-associated and 29% freely removable. At all timepoints, the parenchymal cells contained more activity than non-parenchymal cells. No evidence of antibody-receptor interactions could be obtained either in vivo or in cultures of hepatic parenchymal and non-parenchymal cells. Our data suggest that the bulk of the hepatic burden of 111In MAb results from extravascular pooling of the antibody. PMID:1555890

  19. The European antibody network's practical guide to finding and validating suitable antibodies for research

    PubMed Central

    Roncador, Giovanna; Engel, Pablo; Maestre, Lorena; Anderson, Amanda P.; Cordell, Jacqueline L.; Cragg, Mark S.; Šerbec, Vladka Č.; Jones, Margaret; Lisnic, Vanda J.; Kremer, Leonor; Li, Demin; Koch-Nolte, Friedrich; Pascual, Núria; Rodríguez-Barbosa, Jose-Ignacio; Torensma, Ruurd; Turley, Helen; Pulford, Karen; Banham, Alison H.

    2016-01-01

    Antibodies are widely exploited as research/diagnostic tools and therapeutics. Despite providing exciting research opportunities, the multitude of available antibodies also offers a bewildering array of choice. Importantly, not all companies comply with the highest standards, and thus many reagents fail basic validation tests. The responsibility for antibodies being fit for purpose rests, surprisingly, with their user. This paper condenses the extensive experience of the European Monoclonal Antibody Network to help researchers identify antibodies specific for their target antigen. A stepwise strategy is provided for prioritising antibodies and making informed decisions regarding further essential validation requirements. Web-based antibody validation guides provide practical approaches for testing antibody activity and specificity. We aim to enable researchers with little or no prior experience of antibody characterization to understand how to determine the suitability of their antibody for its intended purpose, enabling both time and cost effective generation of high quality antibody-based data fit for publication. PMID:26418356

  20. Polyclonal and monoclonal antibodies in clinic.

    PubMed

    Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

    2014-01-01

    Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic. PMID:24037837

  1. Establishment of the first WHO Erythropoietin antibody reference panel: Report of an international collaborative study.

    PubMed

    Wadhwa, Meenu; Mytych, Daniel T; Bird, Chris; Barger, Troy; Dougall, Thomas; Han, Hong; Rigsby, Peter; Kromminga, Arno; Thorpe, Robin

    2016-08-01

    A panel of 9 fully human monoclonal antibodies against human erythropoietin (EPO) with defined characteristics (non-neutralizing, neutralizing, various isotypes, affinities) representative of those evident in antibody-mediated pure red cell aplasia (PRCA) and non-PRCA patients were formulated and lyophilized. The panel was evaluated in a multi-centre international collaborative study comprising eighteen different laboratories using different assay platforms including those in routine use. These included binding assays, some based on use of novel technologies and neutralization assays predominantly employing EPO responsive cell-lines. Results showed that detection and titre varied depending on antibody characteristics and the method used. Only selective assay platforms were capable of detecting the diverse repertoire of EPO antibodies in the panel indicating that some clinically relevant antibodies are likely to be missed in some assays. Importantly, the clinical samples from PRCA patients were distinguished as antibody-positive and the healthy donor serum as antibody negative across all different platforms tested. For neutralization, data was generally consistent across the assays for the different samples regardless of the cell-line and the assay conditions. The heterogeneity in data from the study clearly indicated the need for reference standards for consistency in detecting and measuring EPO antibodies across different assay platforms for monitoring the safety and efficacy of erythropoiesis stimulating agents. Therefore, the WHO ECBS at its meeting in October'15 established the EPO antibody panel, available from NIBSC, to facilitate decision-making on assay selection for testing antibodies against human EPO, for evaluating assay performance of antibody assays for clinical use, for assay validation and for standardization. PMID:27173074

  2. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen

    PubMed Central

    Hart, Peter J.; O’Shaughnessy, Colette M.; Siggins, Matthew K.; Bobat, Saeeda; Kingsley, Robert A.; Goulding, David A.; Crump, John A.; Reyburn, Hugh; Micoli, Francesca; Dougan, Gordon; Cunningham, Adam F.; MacLennan, Calman A.

    2016-01-01

    Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies. PMID:26741681

  3. Western Blotting Inaccuracies with Unverified Antibodies: Need for a Western Blotting Minimal Reporting Standard (WBMRS)

    PubMed Central

    Gilda, Jennifer E.; Ghosh, Rajeshwary; Cheah, Jenice X.; West, Toni M.; Bodine, Sue C.; Gomes, Aldrin V.

    2015-01-01

    Western blotting is a commonly used technique in biological research. A major problem with Western blotting is not the method itself, but the use of poor quality antibodies as well as the use of different experimental conditions that affect the linearity and sensitivity of the Western blot. Investigation of some conditions that are commonly used and often modified in Western blotting, as well as some commercial antibodies, showed that published articles often fail to report critical parameters needed to reproduce the results. These parameters include the amount of protein loaded, the blocking solution and conditions used, the amount of primary and secondary antibodies used, the antibody incubation solutions, the detection method and the quantification method utilized. In the present study, comparison of ubiquitinated proteins in rat heart and liver samples showed different results depending on the antibody utilized. Validation of five commercial ubiquitin antibodies using purified ubiquitinated proteins, ubiquitin chains and free ubiquitin showed that these antibodies differ in their ability to detect free ubiquitin or ubiquitinated proteins. Investigating proteins modified with interferon-stimulated gene 15 (ISG15) in young and old rat hearts using six commercially available antibodies showed that most antibodies gave different semi-quantitative results, suggesting large variability among antibodies. Evidence showing the importance of the Western blot buffer and the concentration of antibody used is presented. Hence there is a critical need for comprehensive reporting of experimental conditions to improve the accuracy and reproducibility of Western blot analysis. A Western blotting minimal reporting standard (WBMRS) is suggested to improve the reproducibility of Western blot analysis. PMID:26287535

  4. Antibody-drug conjugate payloads.

    PubMed

    Anderl, Jan; Faulstich, Heinz; Hechler, Torsten; Kulke, Michael

    2013-01-01

    Toxin payloads, or drugs, are the crucial components of therapeutic antibody-drug conjugates (ADCs). This review will give an introduction on the requirements that make a toxic compound suitable to be used in an antitumoral ADC and will summarize the structural and mechanistic features of four drug families that yielded promising results in preclinical and clinical studies. PMID:23913141

  5. Studies on antiplague haemagglutinating antibodies

    PubMed Central

    Suzuki, Sosuke; Chikasato, Yoshio; Hotta, Susumu

    1974-01-01

    The indirect haemagglutination (IHA) test has been widely applied in the detection of antiplague antibodies in rodent sera. In the present study, acetone treatment of the test serum was tried in order to improve the specificity of the reaction. It was shown that the IHA titres of acetone-treated sera correlated well with those of untreated sera measured by the standard method recommended by WHO. Essentially the same results were obtained with sera from experimentally immunized rodents and from captured wild rats. In addition to acetone treatment, the sera were treated with 2-mercaptoethanol (ME). The results obtained indicated that the antiplague IHA antibodies produced early after the inoculation of plague bacilli were ME-sensitive, whereas those detected in the later stages or after a second inoculation were ME-resistant. The data suggest that acetone treatment of sera could be useful for the screening of antiplague antibodies, and that treatment with ME is helpful in assessing the time of past plague infections. The present survey has also shown that the positive rates of antiplague antibodies in wild rats trapped in Kobe, one of the largest sea ports in Japan, have so far been very low. PMID:4549347

  6. Alloimmunization due to red cell antibodies in Rhesus positive Omani Pregnant Women: Maternal and Perinatal outcome

    PubMed Central

    Al-Dughaishi, Tamima; Al-Rubkhi, Ikhlass S.; Al-Duhli, Maymoona; Al-Harrasi, Yusra; Gowri, Vaidyanathan

    2015-01-01

    Objective: This study is aimed to determine the prevalence of alloimmunization due to antibodies to red blood cell (RBC) antigens (other than rhesus [Rh] antigen) and report the maternal, perinatal, and neonatal outcomes. Materials and Methods: A retrospective review of medical records of all patients with minor RBCs antibodies alloimmunization who were followed and delivered at Sultan Qaboos University Hospital, Oman from June 2011 to June 2013. Maternal characteristics, antibody type, antibody titer in addition to perinatal and neonatal outcomes were reviewed. Results: There were 1160 patients with Rh positive status in the study. The most common ABO blood group was O, followed by A, B, and AB. We found 33 out of 1160 Rh positive women alloimmunized with minor RBCs antibodies that gave a prevalence of minor RBCs alloimmunization of 2.7%. The most frequent antibody was anti-E 38%, followed by anti-c 17% and anti-kell 17%. 6 of these 33 patients were identified to have significant antibody titer, and two cases showed evidence of fetal anemia. Only one case required an intrauterine blood transfusion. The most common neonatal complication was jaundice in 53%, followed by respiratory distress syndrome in 28%. Two cases complicated by neonatal anemia required a postnatal blood transfusion. Conclusion: Alloimmunization with anti-E, anti-c, and anti-kell were the most common antibodies among the study group. Minor RBCs alloimmunization was an important cause of neonatal morbidity. PMID:26420934

  7. Systematic fractionation of serum antibodies using multiple antigen homologous peptides as affinity ligands.

    PubMed

    Tribbick, G; Triantafyllou, B; Lauricella, R; Rodda, S J; Mason, T J; Geysen, H M

    1991-06-01

    The fractionation of polyclonal antibodies on multiple peptide ligands is described. The method is an application of a procedure for the synthesis of large numbers of peptides on individual polyethylene pins (Geysen et al., 1987). In this application, each pin-bound peptide is used as an affinity support. Antibodies bound to the peptides are then eluted, using buffers of either high or low pH. Each eluted antibody is then tested for specific binding to peptides or proteins, using ELISA procedures. A rabbit antiserum raised to gonococcal pilin was fractionated on a complete set of octapeptides homologous with the sequence of the pilin protein. Antibodies eluted from some of the peptides bound to pilin in solution. In a second example three hyperimmune sera raised to three different potyviruses were fractionated on their respective homologous peptide sequences. Testing the eluted antibodies on the three virus coat proteins revealed peptides which bound cross-reacting antibodies. Thus the method can be used to confirm direct peptide binding evidence for sequential epitopes. These peptides can then be used in affinity chromatography to increase the specificity of polyclonal sera. This can be achieved either by elution of the specific antibody from the peptide or by removal of cross-reacting antibodies from the whole serum by absorption on peptide. PMID:1904463

  8. Cryptococcus neoformans: paradigm for the role of antibody immunity against fungi?

    PubMed

    Pirofski, L A; Casadevall, A

    1996-08-01

    Cryptococcus neoformans is an encapsulated fungus that is a frequent cause of life-threatening infections in patients with AIDS. C. neoformans has many similarities with encapsulated bacteria such as S. pneumoniae and H. influenzae for which antibody immunity is important in protection. However the role of antibody immunity in protection against C. neoformans has been controversial. Experiments with polyclonal sera have produced conflicting evidence for and against the importance of antibody immunity in host defense. Experiments with monoclonal antibodies (mAb) to the C. neoformans capsular polysaccharide (CPS) have revealed the existence of protective, non-protective and disease-enhancing mAbs, suggesting that the divergent results obtained with polyclonal preparations may be a result of relative proportion of protective and non-protective antibodies in immune sera. Administration of protective mAbs can prolong survival, decrease organ fungal burden, and reduce serum polysaccharide antigen. In vitro experiments suggests that protective mAbs modify the course of infection by enhancing effector cell function against C. neoformans. Addition of mAb to antifungal drugs enhances their efficacy against C. neoformans in vivo and in vitro. Human-mouse chimeric antibodies with activity against C. neoformans have been constructed. A highly immunogenic capsular polysaccharide-protein vaccine has been synthesized that elicits protective antibodies in mice. Antibody immunity elicited by conjugate vaccines or provided by passive administration may be useful in the prevention treatment of human cryptococcal infections. PMID:8899968

  9. Temporal Variation in Sindbis Virus Antibody Prevalence in Bird Hosts in an Endemic Area in Sweden.

    PubMed

    Hesson, Jenny Christina; Lundström, Jan O; Tok, Atalay; Östman, Örjan; Lundkvist, Åke

    2016-01-01

    Sindbis virus (SINV) is a mosquito-borne bird virus that occasionally causes human disease in Fennoscandia, suggested to have cyclic 7-year intervals between outbreaks. Reliable data on human infections in Sweden is however lacking. Here we investigated the SINV antibody prevalence among birds in a Swedish area endemic to SINV to scrutinize if a cyclic variation in antibody prevalence is present in the natural host of SINV. Serum from birds were sampled in the summers of 2002-2004 and 2009 in the floodplains of the River Dalälven in central Sweden, with 2002 and 2009 representing hypothesized years of SINV outbreaks. A total of 963 birds from 52 species (mainly passerines) were tested for the presence of SINV antibodies using a plaque reduction neutralization test. The highest SINV antibody prevalence was found in Turdidae species, specifically Fieldfare, Redwing and Song thrush in which more than 70% of sampled individuals had antibodies to SINV in 2009. The SINV antibody prevalence significantly varied between years with 2% in 2002, 8% in 2003, 14% in 2004 and 37% in 2009. Antibodies were found equally often in hatchlings and in adults and increased from early to late in the season. Clearly, the SINV antibody prevalence was not elevated in the bird hosts in the predicted outbreak year 2002, thus solid evidence of a cyclic occurrence of SINV in Sweden is still lacking. PMID:27579607

  10. Ecological and life-history factors influencing the evolution of maternal antibody allocation: a phylogenetic comparison

    PubMed Central

    Addison, BriAnne; Klasing, Kirk C.; Robinson, W. Douglas; Austin, Suzanne H.; Ricklefs, Robert E.

    2009-01-01

    Maternally derived yolk antibodies provide neonates with immune protection in early life at negligible cost to mothers. However, developmental effects on the neonate's future immunity are potentially costly and thus could limit yolk antibody deposition. The benefits to neonatal immunity must be balanced against costs, which may depend on neonate vulnerability to pathogens, developmental trajectories and the immunological strategies best suited to a species' pace of life. We measured yolk antibodies and life-history features of 23 species of small Neotropical birds and assessed the evidence for each of several hypotheses for life history and ecological effects on the evolution of yolk antibody levels. Developmental period and yolk antibodies are negatively related, which possibly reflect the importance of humoral immune priming through antigen exposure, and selection to avoid autoimmunity, in species with a slower pace of life. There is also a strong relationship between body size and yolk antibody concentration, suggesting that larger species are architecturally equipped to produce and transfer higher concentrations of antibodies. These results suggest that developmental effects of maternally derived antibodies, such as imprinting effects on B-cell diversity or autoimmune effects, are important and deserve more consideration in future research. PMID:19710063

  11. Detection of Campylobacter species using monoclonal antibodies

    NASA Astrophysics Data System (ADS)

    Young, Colin R.; Lee, Alice; Stanker, Larry H.

    1999-01-01

    A panel of species specific monoclonal antibodies were raised to Campylobacter coli, Campylobacter jejuni and Campylobacter lari. The isotypes, and cross-reactivity profiles of each monoclonal antibody against an extensive panel of micro- organisms, were determined.

  12. Progranulin antibodies in autoimmune diseases.

    PubMed

    Thurner, Lorenz; Preuss, Klaus-Dieter; Fadle, Natalie; Regitz, Evi; Klemm, Philipp; Zaks, Marina; Kemele, Maria; Hasenfus, Andrea; Csernok, Elena; Gross, Wolfgang L; Pasquali, Jean-Louis; Martin, Thierry; Bohle, Rainer Maria; Pfreundschuh, Michael

    2013-05-01

    Systemic vasculitides constitute a heterogeneous group of diseases. Autoimmunity mediated by B lymphocytes and their humoral effector mechanisms play a major role in ANCA-associated vasculitis (AAV) as well as in non-ANCA associated primary systemic vasculitides and in the different types of autoimmune connective tissue disorders and rheumatoid arthritis. In order to detect autoantibodies in systemic vasculitides, we screened protein macroarrays of human cDNA expression libraries with sera from patients with ANCA-associated and ANCA-negative primary systemic vasculitides. This approach led to the identification of antibodies against progranulin, a 88 kDA secreted glycoprotein with strong anti-inflammatory activity in the course of disease of giant-cell arteritis/polymyalgia rheumatica (14/65), Takayasu's arteritis (4/13), classical panarteritis nodosa (4/10), Behcet's disease (2/6) and in the course of disease in granulomatosis with polyangiitis (31/75), Churg-Strauss syndrome (7/23) and in microscopic polyangiitis (7/19). In extended screenings the progranulin antibodies were also detected in other autoimmune diseases such as systemic lupus erythematosus (39/91) and rheumatoid arthritis (16/44). Progranulin antibodies were detected only in 1 of 97 healthy controls. Anti-progranulin positive patients with systemic vasculitides, systemic lupus erythematosus or rheumatoid arthritis had significant lower progranulin plasma levels, indicating a neutralizing effect. In light of the anti-inflammatory effects of progranulin, progranulin antibodies might exert pro-inflammatory effects thus contributing to the pathogenesis of the respective autoimmune diseases and might serve as a marker for disease activity. This hypothesis is supported by the fact that a positive progranulin antibody status was associated with active disease in granulomatosis with polyangiitis. PMID:23149338

  13. Use of an indirect enzyme-linked immunosorbent assay for detection of antibodies in sheep naturally infected with Salmonella Abortusovis.

    PubMed

    Wirz-Dittus, Sophie; Belloy, Luc; Doherr, Marcus G; Hüssy, Daniela; Sting, Reinhard; Gabioud, Patricia; Waldvogel, Andreas S

    2010-07-01

    An indirect enzyme-linked immunosorbent assay (ELISA) was modified and validated to detect antibodies against Salmonella Abortusovis in naturally infected sheep. The ELISA was validated with 44 positive and 45 negative control serum samples. Compared with the immunoblot, the sensitivity and specificity of the assay were 98% and 100%, respectively. To follow antibody levels over time, samples from 12 infected ewes were collected at 1, 3, and 10 months after abortion. All animals showed antibody levels above the cutoff value throughout the observation period. One and 3 months after abortion, high antibody levels could be detected in all but one animal, whereas after 10 months, 9 animals had markedly lower but still positive antibody levels. The test characteristics and evidence for the persistence of detectable antibody levels in all infected animals for up to 10 months indicates that the ELISA can be used for herd surveillance testing. PMID:20622222

  14. Regulation of Immune Response by Autogenous Antibody against Receptor

    PubMed Central

    Kluskens, L.; Köhler, H.

    1974-01-01

    BALB/c mice repeatedly immunized with Pneumococcus R36A vaccine produce antibodies to phosphorylcholine having the TEPC-15 myeloma idiotype (murine IgA myeloma protein that binds phosphorylcholine). The plaque-forming cell response to phosphorylcholine shows a decrease with repeated immunizations. In contrast, spleen cells from multiply immunized mice responded better in vitro than spleen cells from nonimmunized mice. The serum of animals immunized four or five times agglutinates TEPC-15-coated sheep erythrocytes. Inhibition of hemagglutination shows that the agglutinating activity is directed against the TEPC-15 idiotype. Sera from these mice, when added to cultures of normal spleen cells, specifically suppress the response to phosphorylcholine. The suppressive activity in the serum can be removed by solid absorption with TEPC-15. Evidently, repeated immunization with antigen induces two kinds of antibody responses: one directed against antigen and the other directed against the antibody to the antigen. It is proposed that this “auto” antibody against receptor is involved in the regulation of the immune response. PMID:4140517

  15. The Use of Monoclonal Antibodies in Human Prion Disease

    NASA Astrophysics Data System (ADS)

    Bodemer, Walter

    Detection of PrP and its pathological isoform(s) is the key to understanding the etiology and pathogenesis of transmissible spongiform encephalopathy. There is ample evidence that PrP isoforms constitute a major component of an unknown and perhaps unconventional infectious agent. An etiological relationship between human and zoonotic transmissible spongiform encephalopathies may be revealed with monoclonal antibodies. Knowledge of the conformational transition rendering a nonpathogenic, almost ubiquitous cellular protein into a pathogenic one is crucial to defining pathomechanisms. The stepwise or even continuous formation of pathogenic molecules can be monitored. Any improvement in the early diagnosis could help to conceive new therapeutic measures which are not currently available. Determination of PrP isoforms in tissue, cells, or body fluids may be of prognostic value. Many experimental approaches in molecular medicine and molecular biology of the prion protein already rely on monoclonal antibodies. Recombinant antibodies such as the single-chain Fv may soon replace traditional hybridoma techniques. Binding affinity can easily be manipulated by a number of techniques, including in vitro mutagenesis - a step which could never be carried out using the traditional hybridoma technology. Monoclonal antibodies are and will remain an essential support for ongoing research on the prion protein in general and on the unconventional infectious prions.

  16. Mechanisms of resistance to HER family targeting antibodies

    SciTech Connect

    Kruser, Tim J.; Wheeler, Deric L.

    2010-04-15

    The epidermal growth factor (EGF) family of receptor tyrosine kinases consists of four members: EGFR (HER1/ErbB1), HER2/neu (ErbB2), HER3 (ErbB3) and HER4 (ErbB4). Receptor activation via ligand binding leads to downstream signaling that influence cell proliferation, angiogenesis, invasion and metastasis. Aberrant expression or activity of EGFR and HER2 have been strongly linked to the etiology of several human epithelial cancers including but not limited to head and neck squamous cell carcinoma (HNSCC), non-small cell lung cancer (NSCLC), colorectal cancer (CRC), and breast cancer. With this, intense efforts have been made to inhibit the activity of the EGFR and HER2 by designing antibodies against the ligand binding domains (cetuximab, panitumumab and trastuzumab) or small molecules against the tyrosine kinase domains (erlotinib, gefitinib, and lapatinib). Both approaches have shown considerable clinical promise. However, increasing evidence suggests that the majority of patients do not respond to these therapies, and those who show initial response ultimately become refractory to treatment. While mechanisms of resistance to tyrosine kinase inhibitors have been extensively studied, resistance to monoclonal antibodies is less well understood, both in the laboratory and in the clinical setting. In this review, we discuss resistance to antibody-based therapies against the EGFR and HER2, similarities between these resistance profiles, and strategies to overcome resistance to HER family targeting monoclonal antibody therapy.

  17. Effects of medium concentration on antibody production

    NASA Technical Reports Server (NTRS)

    Williams, J.

    1984-01-01

    Antibody production by two different cell lines was measured as the media were supplemented with varied amounts of glucose and fetal bovine serum. Both cell lines elaborated antidinitrophenyl hapten antibodies. Two basic media were used: RPMI 1640 and Dulbecco's modified Eagle's medium. The production of antibodies was followed from 0 to 180 h and was assayed by radioimmunoassay.

  18. Antibodies against mumps virus component proteins.

    PubMed

    Matsubara, Keita; Iwata, Satoshi; Nakayama, Tetsuo

    2012-08-01

    The neutralization (NT) test is regarded as the most reliable method for detection of protective antibodies, but is labor-intensive and time consuming. Enzyme-linked immunosorbent assay (EIA) is frequently used in sero-epidemiological studies because of its simplicity and ease of use. In this study, immunofluorescent (IF) antibodies against nucleocapsid (N), fusion (F), and hemagglutinin-neuraminidase (HN) proteins were investigated in comparison with NT and EIA antibodies. The antibody against N protein was dominant in serum samples obtained from patients with a previous history of mumps infection. Titers of antibodies against F and HN proteins were very low. Many serum samples were positive for EIA but negative for NT, and no significant correlation was noted between NT and EIA antibodies. Among the three component proteins, correlation of EIA and IF antibodies with N protein was relatively good. After vaccination with mumps vaccine, EIA positivity was closely related to the IF antibodies against N protein, and after vaccination NT-positive sera became positive for IF antibodies against F and HN proteins. IF antibodies against F and HN proteins were considered to have a strong association with NT antibodies, and those against N protein were considered to have a strong association with EIA antibodies. PMID:22215227

  19. Anti-DNA antibodies in SLE

    SciTech Connect

    Voss, E.W.

    1988-01-01

    This book contains 8 chapters. Some of the titles are: Anti-DNA Antibodies in SLE: Historical Perspective; Specificity of Anti-DNA Antibodies in Systemic Lupus Erythematosus; Monoclonial Autoimmune Anti-DNA Antibodies; and Structure--Function Analyses of Anti-DNA Autoantibodies.

  20. Synopsis of antinuclear antibodies in dermatology.

    PubMed

    Nelson, Michael M; Heffernan, Michael P

    2002-06-01

    Antinuclear antibodies (ANA) provide a powerful tool in diagnosing the connective tissue diseases. The fundamentals of antinuclear antibody testing and the sensitivity, specificity, and prognostic value of antinuclear antibodies and their associated illnesses will be discussed. As skin manifestations are common with connective tissue diseases, knowledge of the diagnostic and prognostic value of ANA testing is essential to the nurse in dermatology. PMID:12099064

  1. Specific antibody for pesticide residue determination produced by antibody-pesticide complex

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new method for specific antibody production was developed using antibody (Ab)-pesticide complex as a unique immunogen. Parathion (PA) was the targeted pesticide, and rabbit polyclonal antibody (Pab) and mouse monoclonal antibody (Mab) were used as carrier proteins. The Ab-PA complexes were genera...

  2. New Insights into the Functional Behavior of Antibodies as Revealed by Binding Studies on an Anti-Uranium Monoclonal Antibody

    SciTech Connect

    Blake, Diane A.; Xia Li; Haini Yu; Blake, Robert C.

    2004-03-17

    As part of an ongoing effort to develop immunoassays for chelated uranium(VI) on a hand-held flow fluorimeter, an anti-uranium monoclonal antibody designated as 8A11 was fluorescently labeled using two different strategies. When 8A11 was coupled via reactive lysines to either ALEXATM 488 or Cy5TM, the resulting fluorescent antibody conjugate exhibited positive cooperativity in the presence of its antigen, U(VI) chelated with 2,9-dicarboxy-1,10-phenanthroline (U(VI)-DCP). That is, when one of the two binding sites on the covalently modified 8A11 was occupied with bound antigen, the affinity of the remaining site on the antibody for U(VI)-DCP appeared to increase. Unmodified 8A11 bound U(VI)-DCP with the expected hyperbolic dependence on the concentration of antigen, consistent with independent and equal binding of ligand at both sites. Proteolytic cleavage of the fluorescently conjugated 8A11 to produce the fluorescent monovalent Fab fragment yielded an active preparation that now bound U(VI)-DCP with no evidence of positive cooperativity. Although, in principle, any divalent antibody has the potential to exhibit positive cooperativity in its binding interactions with its antigen, very little literature precedent for this type of behavior exists. Native 8A11 was also noncovalently labeled with highly fluorescent ZENONTM reagents. These reagents are fluorescently-labeled Fab fragments of goat anti-mouse antibodies that bind to the Fc portion of 8A11. These high-affinity, monovalent fluorescent reagents permitted the intact 8A11 mouse antibody to be labeled in situ with no covalent modifications. Incubation of the 8A11 with ZENON 647 produced a fluorescent protein complex that showed an 8-fold higher affinity for U(VI)-DCP than did the free 8A11 alone. Again, very few literature precedents exist for this phenomenon, where agents that bind to the Fc portion of an intact antibody change the affinity of the antibody for the antigen at the structurally distant Fab portion

  3. Antibody biosimilars: Fears or opportunities?

    PubMed Central

    Guillon-Munos, Audrey; Daguet, Arnaud; Watier, Hervé

    2014-01-01

    The annual “LabEx MAbImprove industrial workshops” are primarily intended to provide scientists involved in therapeutic antibodies, a comprehensive view about topics of interest for the pharmaceutical industry. They are organized by the “LabEx MAbImprove industrial committee”, for this first edition especially in partnership with ARITT, the regional agency for innovation and technology transfer which operates in the French Région Centre, the 1st French region for pharmaceutical production. The 2013 edition, held May 28 at the Vinci Center of Tours, was dedicated to antibody biosimilars. Depending on opinions, the impending expiry of antibody patents and the imminent marketing approval of competitors to blockbusters can be perceived as good or bad things. Fears or opportunities? Risks for patients? Breath of fresh air for the health systems? Opportunity for re-industrializing France? In this context, it is necessary for people to form a fair and informed opinion on the current landscape of antibody biosimilars. In particular, this is especially important for scientists from the academic world, from the industry or from the regulation agencies, for pharmacists, for pharmacovigilance specialists, for health authorities, and staff from health insurance and decision makers. The first session was devoted to market and regulatory issues, and included both an overview of the evolution of the patent landscape and a description of biosimilars regulation in the European Union (EU). This session was closed by a talk on manufacturing processes for biosimilars. In the next session, quality control attributes of biosimilars were discussed and compared with the consistent quality of biotechnology products to raise the question: “How close is close enough?” In vitro assays for evaluating the Fc function of therapeutic antibodies were also discussed. The third session focused on development of biosimilars and primarily on the stepwise process for introducing an antibody

  4. Neutralizing Antibodies Against Interferon-Beta

    PubMed Central

    2008-01-01

    The development of neutralizing antibodies (NAbs) is a major problem in multiple sclerosis (MS) patients treated with interferon-beta (IFN-ß). Whereas binding antibodies (BAbs) can be demonstrated in the vast majority of patients, only a smaller proportion of patients develop NAbs. The principle in NAb in vitro assays is the utilization of cultured cell lines that are responsive to IFN-ß. The cytopathic effect (CPE) assay measures the capacity of NAbs to neutralize IFN- ß's protective effect on cells challenged with virus and the MxA induction assay measures the ability of NAbs to reduce the IFN-ß-induced expression of MxA, either at the mRNA or the protein level. A titer of >20 neutralizing units/ml traditionally defines NAb posi-tivity. NAbs in high titers completely abrogate the in vivo response to IFN-ß, whereas the effect of low and intermediate titers is unpredictable. As clinically important NAbs appear only after 9-18 months IFN- ß0 therapy, short-term studies of two years or less are unsuitable for evaluation of clinical NAb effects. All long-term trials of three years or more concordantly show evidence of a detrimental effect of NAbs on relapses, disease activity on MRI, or on disease progression. Persistent high titers of NAbs indicate an abrogation of the biological response and, hence, absence of therapeutic efficacy, and this observation should lead to a change of therapy. As low and medium titers are ambiguous treatment decisions in patients with low NAb titres should be guided by determination of in vivo mRNA MxA induction and clinical disease activity. PMID:21180570

  5. Anti-brain antibodies in PANDAS versus uncomplicated streptococcal infection.

    PubMed

    Pavone, Piero; Bianchini, Rio; Parano, Enrico; Incorpora, Gemma; Rizzo, Renata; Mazzone, Luigi; Trifiletti, Rosario R

    2004-02-01

    The objective of this study was to assess brain involvement through the presence of antineuronal antibodies in Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus (PANDAS) and in uncomplicated active Group A streptococcal infection. We compared serum antibrain antibody to human basal ganglia sections assessed by indirect tissue immunofluorescence in two groups: a PANDAS group, comprised of 22 patients (mean age 10.1 years; 20 male, 2 female) who met strict National Institutes of Mental Health diagnostic criteria for PANDAS and had clinically active tics or obsessive-compulsive disorder, or both; and a GABHS control group consisting of 22 patients (mean age 9.1 years; 15 mol/L, 7 female) with clinical evidence of active Group A beta-hemolytic streptococcal (GABHS) infection confirmed by throat culture and elevated antistreptolysin O titers but without history or clinical evidence of tics or obsessive-compulsive disorder. We observed positive anti-basal ganglia staining (defined as detectable staining at 1:10 serum dilution) in 14/22 patients in the PANDAS group (64%) but only 2/22 (9%) in the GABHS control group (P < 0.001, Fisher's exact test). These results suggest that antibrain antibodies are present in children with PANDAS that cannot be explained merely by a history of GABHS infection. PMID:14984902

  6. Monoclonal antibodies against Vibrio cholerae lipopolysaccharide.

    PubMed Central

    Gustafsson, B; Rosén, A; Holme, T

    1982-01-01

    A cell line producing monoclonal antibodies directed against the core region of Vibrio cholerae lipopolysaccharide has been established. These antibodies were inhibited by lipopolysaccharide preparations of both O-group 1 vibrios and some non-O-group 1 vibrios as detected in enzyme-linked immunosorbent assay-inhibition experiments. Coagglutination experiments with monoclonal and polyclonal antibodies adsorbed to protein A-carrying staphylococci were performed. All V. cholerae strains tested, regardless of serotype, were agglutinated when mixed with staphylococci coated with the monoclonal antibodies, whereas staphylococci coated with group-specific (O1) polyclonal antibodies only agglutinated with O-group 1 vibrios. Images PMID:6183214

  7. Production of Monoclonal Antibody against Human Nestin.

    PubMed

    Hadavi, Reza; Zarnani, Amir Hassan; Ahmadvand, Negah; Mahmoudi, Ahmad Reza; Bayat, Ali Ahmad; Mahmoudian, Jafar; Sadeghi, Mohammad-Reza; Soltanghoraee, Haleh; Akhondi, Mohammad Mehdi; Tarahomi, Majid; Jeddi-Tehrani, Mahmood; Rabbani, Hodjattallah

    2010-04-01

    We have employed a peptide-based antibody generation protocol for producing antibody against human nestin. Using a 12-mer synthetic peptide from repetitive region of human nestin protein devoid of any N- or O-glyco-sylation sequences, we generated a mouse monoclonal antibody capable of recognizing human, mouse, bovine, and rat nestin. A wide variety of nestin proteins ranging from 140-250 kDa was detected by this antibody. This antibody is highly specific and functional in applications such as ELISA, flow cytometry, immunocytochemistry, and Western blot assays. PMID:23407796

  8. Production of Monoclonal Antibody against Human Nestin

    PubMed Central

    Hadavi, Reza; Zarnani, Amir Hassan; Ahmadvand, Negah; Mahmoudi, Ahmad Reza; Bayat, Ali Ahmad; Mahmoudian, Jafar; Sadeghi, Mohammad-Reza; Soltanghoraee, Haleh; Akhondi, Mohammad Mehdi; Tarahomi, Majid; Jeddi-Tehrani, Mahmood; Rabbani, Hodjattallah

    2010-01-01

    We have employed a peptide-based antibody generation protocol for producing antibody against human nestin. Using a 12-mer synthetic peptide from repetitive region of human nestin protein devoid of any N- or O-glyco-sylation sequences, we generated a mouse monoclonal antibody capable of recognizing human, mouse, bovine, and rat nestin. A wide variety of nestin proteins ranging from 140–250 kDa was detected by this antibody. This antibody is highly specific and functional in applications such as ELISA, flow cytometry, immunocytochemistry, and Western blot assays. PMID:23407796

  9. The role of antibodies in myasthenia gravis.

    PubMed

    De Baets, M; Stassen, M H W

    2002-10-15

    Myasthenia gravis is an autoimmune disease associated with antibodies directed to the postsynaptic acetylcholine receptor. These antibodies reduce the number of receptors. Autoantibodies against AChR and other muscle antigens can be used for the diagnosis of myasthenia gravis and related disorders. The origin and the role of these antibodies in the disease are discussed. Experimental autoimmune myasthenia gravis, an experimental model closely mimicking the disease, has provided answers to many questions about the role of antibodies, complement macrophages and AChR anchor proteins. Genetically modified anti-AChR antibodies may also be used in the future to treat myasthenia. PMID:12220686

  10. Antibody engineering and therapeutics conference

    PubMed Central

    Larrick, James W; Parren, Paul WHI; Huston, James S; Plückthun, Andreas; Bradbury, Andrew; Tomlinson, Ian M; Chester, Kerry A; Burton, Dennis R; Adams, Gregory P; Weiner, Louis M; Scott, Jamie K; Alfenito, Mark R; Veldman, Trudi; Reichert, Janice M

    2014-01-01

    The 25th anniversary of the Antibody Engineering & Therapeutics Conference, the Annual Meeting of The Antibody Society, will be held in Huntington Beach, CA, December 7–11, 2014. Organized by IBC Life Sciences, the event will celebrate past successes, educate participants on current activities and offer a vision of future progress in the field. Keynote addresses will be given by academic and industry experts Douglas Lauffenburger (Massachusetts Institute of Technology), Ira Pastan (National Cancer Institute), James Wells (University of California, San Francisco), Ian Tomlinson (GlaxoSmithKline) and Anthony Rees (Rees Consulting AB and Emeritus Professor, University of Bath). These speakers will provide updates of their work, placed in the context of the substantial growth of the industry over the past 25 years. PMID:25517297