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1

Murine monoclonal antibodies specific for virulent Treponema pallidum (Nichols).  

PubMed Central

Murine anti-Treponema pallidum (Nichols) lymphocyte hybridoma cell lines secreting monoclonal antibodies against a variety of treponemal antigens have been generated. Hybridomas isolated were of three major types: those that were directed specifically against T. pallidum antigens, those that were directed against treponemal group antigens (as evidenced by their cross-reactivity with T. phagedenis biotype Reiter antigens), and those that cross-reacted with both treponemal as well as rabbit host testicular tissue antigens. The majority (31 of 39 clones) of these anti-T. pallidum hybridomas, which produced monoclonal antibodies of mouse isotypes immunoglobulin G1 (IgG1), IgG2a, IgG2b, IgG3 or IgM, were directed specifically against T. pallidum and not other treponemal or rabbit antigens tested by radioimmunoassay. Four of these T. pallidum-specific hybridomas secreted monoclonal antibodies with greater binding affinity for "aged" rather than freshly isolated intact T. pallidum cells, suggesting a possible specificity for "unmasked" surface antigens of T. pallidum. Six anti-T. pallidum hybridomas produced complement-fixing monoclonal antibodies (IgG2a, IgG2b, or IgM) that were capable of immobilizing virulent treponemes in the T. pallidum immobilization (TPI) test; these may represent biologically active monoclonal antibodies against treponemal surface antigens. Three other hybridomas secreted monoclonal antibodies which bound to both T. pallidum and T. phagedenis biotype Reiter antigens, thus demonstrating a possible specificity for treponemal group antigens. Five hybridoma cell lines were also isolated which produced IgM monoclonal antibodies that cross-reacted with all treponemal and rabbit host testicular tissue antigens employed in the radioimmunoassays. This report describes the construction and characteristics of these hybridoma cell lines. The potential applications of the anti-T. pallidum monoclonal antibodies are discussed. PMID:7047388

Robertson, S M; Kettman, J R; Miller, J N; Norgard, M V

1982-01-01

2

Monoclonal antibody analysis of specific antigenic similarities among pathogenic Treponema pallidum subspecies.  

PubMed Central

Murine monoclonal antibodies directed against a 47,000-dalton immunodominant surface-exposed antigen of Treponema pallidum subsp. pallidum (Nichols) were isolated. These monoclonal antibodies cross-reacted with analogous 47,000-dalton antigens of two other virulent treponemes, T. pallidum subsp. pertenue and T. pallidum subsp. endemicum (Bosnia A), as determined by radioimmunoassay and immunoblot analyses. Immunoelectron microscopy confirmed that the 47,000-dalton antigen of T. pallidum subsp. pallidum was a surface-associated cellular component. Surface binding assays and immunoelectron microscopic studies also suggested that the analogous 47,000-dalton antigenic component of T. pallidum subsp. pertenue may not have been oriented toward the bacterial surface in the same way as the T. pallidum subsp. pallidum antigen or that the relevant antigenic determinant(s) may not have been exposed to the outer surface in the same way. The significance of this antigen relative to its apparent conservation among pathogenic treponemes and its possible diagnostic and vaccinogenic potentials are discussed. Images PMID:6381311

Marchitto, K S; Jones, S A; Schell, R F; Holmans, P L; Norgard, M V

1984-01-01

3

Treponema pallidum Major Sheath Protein Homologue Tpr K Is a Target of Opsonic Antibody and the Protective Immune Response  

Microsoft Academic Search

Summary We have identified a family of genes that code for targets for opsonic antibody and protective immunity in T. pallidum subspecies pallidum using two different approaches, subtraction hybrid- ization and differential immunologic screening of a T. pallidum genomic library. Both ap- proaches led to the identification of a polymorphic multicopy gene family with predicted amino acid homology to the

Arturo Centurion-Lara; Christa Castro; Lynn Barrett; Caroline Cameron; Maryam Mostowfi; Wesley C. Van Voorhis; Sheila A. Lukehart

4

Laboratory evaluation of three rapid diagnostic tests for dual detection of HIV and Treponema pallidum antibodies.  

PubMed

The performance of three research-use-only, dual HIV and syphilis rapid diagnostic tests (RDTs) was evaluated for 150 patient serum samples and compared to reference HIV and Treponema pallidum antibody detection methods. The RDTs performed comparably, with sensitivities of 93 to 99% and specificities of 97 to 100%. The kappa statistic between the RDTs was 0.95. PMID:25297332

Humphries, Romney M; Woo, Jennifer S; Chung, Jun Ho; Sokovic, Anita; Bristow, Claire C; Klausner, Jeffrey D

2014-12-01

5

Serodiagnosis of Syphilis: Antibodies to Recombinant Tp0453, Tp92, and Gpd Proteins Are Sensitive and Specific Indicators of Infection by Treponema pallidum  

Microsoft Academic Search

Syphilis serodiagnosis relies on a combination of nonspecific screening tests (antilipoidal antibodies) and Treponema pallidum-specific tests (anti-T. pallidum antibodies). We studied a group of six recombinant T. pallidum antigens for their sensitivities and specificities with sera from individuals with syphilis (n 43), relapsing fever (n 8), Lyme disease (n 8), and leptospirosis (n 9) and from uninfected individuals (n 15).

Wesley C. Van Voorhis; Lynn K. Barrett; Sheila A. Lukehart; Bruno Schmidt; Martin Schriefer; Caroline E. Cameron

2003-01-01

6

Prevalence of antibodies against Treponema pallidum among HIV-positive patients in a tertiary care hospital in Mexico.  

PubMed

Our objective was to determine the seroprevalence of syphilis among HIV-infected patients in a tertiary care hospital in Mexico City. A cross-sectional study was developed, and 318 HIV-positive patients were evaluated from January to February 2013 at Hospital de Infectología, National Medical Center 'La Raza' (a tertiary care hospital specialising in infectious diseases in Mexico City). Laboratory data were screened for the detection of antibodies against Treponema pallidum. Patients completed a questionnaire relating to socio-demographic data and factors associated with syphilis. Of the 318 patients, 83% were men. The mean age ± SD was 36?±?11 years; 52% were men who have sex with men and 47% had undertaken higher education. The overall seroprevalence of syphilis among these patients was 25% (95% confidence interval 21%, 30%). Men who have sex with men had a significantly higher seroprevalence (30% vs. 15%, p?=?0.009). We conclude that, in Mexico, there is a high seroprevalence of syphilis antibodies in HIV-infected patients and that men who have sex with men are the group most affected. PMID:24713227

Mata-Marín, José Antonio; Sandoval-Sánchez, Juan Joel; Huerta-García, Gloria; Arroyo-Anduiza, Carla Ileana; Alcalá-Martínez, Enrique; Mata-Marín, Luis Alberto; Sandoval-Ramirez, Jorge Luis; Gaytán-Martínez, Jesús

2015-02-01

7

Treponema pallidum subsp. pertenue Displays Pathogenic Properties Different from Those of T. pallidum subsp. pallidum  

PubMed Central

The present study described the susceptibility of C4D guinea pigs to cutaneous infection with Treponema pallidum subsp. pertenue Haiti B strain. The general manifestations of the disease in adults and neonates differ, to a certain degree, from those induced by T. pallidum subsp. pallidum Nichols strain. Noticeable differences between the infections were reflected in the character of the skin lesions, their onset and persistence, and the kinetics of the humoral response. The incidence and dissemination of cutaneous yaws lesions in very young guinea pigs were remarkably different from the low frequency observed in a similar age group of syphilis infection, 100 versus 17%, respectively. Moreover, as opposed to T. pallidum subsp. pallidum, T. pallidum subsp. pertenue does not cross the placenta. Offspring born to yaws-infected mothers did not produce immunoglobulin M antibodies and their organs, examined by PCR and rabbit infectivity test (RIT), were all negative. Examination of a large number of tissues and organs in adult, neonate, and maternal yaws by PCR and RIT clearly demonstrated that, unlike syphilis, there was a low incidence and short persistence of the yaws pathogen in internal organs. These findings stress the dermotropic rather than the organotropic character of yaws and provide further evidence of distinctive biological and pathological differences between yaws and venereal syphilis. PMID:10816466

Wicher, Konrad; Wicher, Victoria; Abbruscato, Frank; Baughn, Robert E.

2000-01-01

8

Comparative Evaluation of Nine Different Enzyme-Linked Immunosorbent Assays for Determination of Antibodies against Treponema pallidum in Patients with Primary Syphilis  

Microsoft Academic Search

Nine different enzyme-linked immunosorbent assays (ELISAs) with a sonicate or recombinant proteins of Treponema pallidum as antigen have been evaluated comparatively by testing 52 highly selected sera from patients with primary syphilis, all negative in the microhemagglutination test for T. pallidum (MHA-TP). Eight tests exhibited greater sensitivity (48.5 to 76.9%) than the commonly used Venereal Disease Research Labo- ratory test

BRUNO L. SCHMIDT; MARZIEH EDJLALIPOUR; ANTON LUGER; Ludwig Boltzmann

2000-01-01

9

Assessment of cell-surface exposure and vaccinogenic potentials of Treponema pallidum candidate outer membrane proteins  

PubMed Central

Syphilis, a sexually transmitted infection caused by the spirochetal bacterium Treponema pallidum, remains a global public health problem. T. pallidum is believed to be an extracellular pathogen and, as such, the identification of T. pallidum outer membrane proteins that could serve as targets for opsonic or bactericidal antibodies has remained a high research priority for vaccine development. However, the identification of T. pallidum outer membrane proteins has remained highly elusive. Recent studies and bioinformatics have implicated four treponemal proteins as potential outer membrane proteins (TP0155, TP0326, TP0483 and TP0956). Indirect immunofluorescence assays performed on treponemes encapsulated within agarose gel microdroplets failed to provide evidence that any of these four molecules were surface-exposed in T. pallidum. Second, recombinant fusion proteins corresponding to all four candidate outer membrane proteins were used separately, or in combination, to vaccinate New Zealand White rabbits. Despite achieving high titers (>1:50,000) of serum antibodies, none of the rabbits displayed chancre immunity after intradermal challenge with viable T. pallidum. PMID:17890130

Tomson, Farol L.; Conley, Patrick G.; Norgard, Michael V.; Hagman, Kayla E.

2007-01-01

10

Sequence Conservation of Glycerophosphodiester Phosphodiesterase among Treponema pallidum Strains  

PubMed Central

Previous investigations have demonstrated that immunization with Treponema pallidum subsp. pallidum glycerophosphodiester phosphodiesterase significantly protects rabbits from subsequent treponeme challenge. In this report, we show that the glycerophosphodiester phosphodiesterase amino acid sequence is conserved among 12 strains from a total of five pathogenic treponemes. The invariant nature of this immunoprotective antigen makes it an attractive candidate for inclusion in a universal subunit vaccine against T. pallidum infection. In addition, these studies show a silent nucleotide substitution at position 579 of the gpd open reading frame which is consistently observed in the non-T. pallidum subsp. pallidum strains. This sequence alteration introduces a PleI restriction site in the nonsyphilis strains and thus allows genetic differentiation from T. pallidum subsp. pallidum strains. PMID:10338539

Cameron, Caroline E.; Castro, Christa; Lukehart, Sheila A.; Van Voorhis, Wesley C.

1999-01-01

11

Complete Genome Sequence of Treponema pallidum, the  

E-print Network

Complete Genome Sequence of Treponema pallidum, the Syphilis Spirochete Claire M. Fraser,* Steven J and substantiates the considerable di- versity observed among pathogenic spirochetes. Venereal syphilis was first century with the age of exploration. Syphilis was ubiquitous by the 19th century and has been called

Salzberg, Steven

12

[The effect of magnetoregulated microfields on Treponema pallidum. 2].  

PubMed

The authors proceed with their studies of magnetic microfields detected round T. pallidum and of the interactions of these fields with the biologic objects round the treponemas; these studies will prompt approaches to physiotherapeutic management of infectious diseases, making use of a new (for medicine) source of physical fields. They have revealed that T. pallidum fluorescence intensity and the width of the 'fan' of T. pallidum on the domain structures of ferrite/garnet films indicates the degree of T. pallidum pathogeneity. PMID:2658407

Milich, M V; Fedorova, D L; Skripkin, Iu K; Antonov, A V; Piruzian, A L

1989-01-01

13

Sequence Diversity of Treponema pallidum subsp. pallidum tprK in Human Syphilis Lesions and Rabbit-Propagated Isolates  

Microsoft Academic Search

The tprK gene of Treponema pallidum subsp. pallidum, the causative agent of venereal syphilis, belongs to a 12-member gene family and encodes a protein with a predicted cleavable signal sequence and predicted transmembrane domains. Except for the Nichols type strain, all rabbit-propagated isolates of T. pallidum examined thus far are comprised of mixed populations of organisms with heterogeneous tprK sequences.

Rebecca E. LaFond; Arturo Centurion-Lara; Charmie Godornes; Anne M. Rompalo; Wesley C. Van Voorhis; Sheila A. Lukehart

2003-01-01

14

Cell response in rabbits infected with T. pallidum as measured by the leucocyte migration inhibition test.  

PubMed Central

Leucocyte migration in agarose was used to examine cell response in 48 rabbits infected with the Nichols strain of T. pallidum for 1 week to 16 months. The response of the peripheral leucocytes to T. pallidum antigen (TpAg), 3 and 15 mug/ml., Reiter antigen (RAg) 6 mug./ml., and VDRL reagent 1:500 was examined. The cells in the presence of RAg, TpAg--3 mug./ml.--and the VDRL reagent demonstrated a biphasic response; in the early stage of infection (until the 4th week) stimulation of leucocyte migration and in the later stage of disease inhibition of leucocyte migration was observed. The higher concentration of TpAg--15 mug./ml.--caused only inhibition of leucocyte migration. The leucocyte response in vitro could not be confirmed by intradermal skin tests with 5 x 10(7) heat-killed T. pallidum. No correlation between the cell response and the treponemal antibodies was observed. PMID:1156847

Wicher, V; Wicher, K

1975-01-01

15

Treponema pallidum Invades Intercellular Junctions of Endothelial Cell Monolayers  

NASA Astrophysics Data System (ADS)

The pathogenesis of syphilis reflects invasive properties of Treponema pallidum, but the actual mode of tissue invasion is unknown. We have found two in vitro parallels of treponemal invasiveness. We tested whether motile T. pallidum could invade host cells by determining the fate of radiolabeled motile organisms added to a HeLa cell monolayer; 26% of treponemes associated with the monolayer in a trypsin-resistant niche, presumably between the monolayer and the surface to which it adhered, but did not attain intracellularity. Attachment of T. pallidum to cultured human and rabbit aortic and human umbilical vein endothelial cells was 2-fold greater than to HeLa cells. We added T. pallidum to aortic endothelial cells grown on membrane filters under conditions in which tight intercellular junctions had formed. T. pallidum was able to pass through the endothelial cell monolayers without altering tight junctions, as measured by electrical resistance. In contrast, heat-killed T. pallidum and the nonpathogen Treponema phagedenis biotype Reiter failed to penetrate the monolayer. Transmission electron micrographs of sections of the monolayer showed T. pallidum in intercellular junctions. Our in vitro observations suggest that these highly motile spirochetes may leave the circulation by invading the junctions between endothelial cells.

Thomas, D. Denee; Navab, Mahamad; Haake, David A.; Fogelman, Alan M.; Miller, James N.; Lovett, Michael A.

1988-05-01

16

Complete genome sequence of Treponema pallidum strain DAL-1  

PubMed Central

Treponema pallidum strain DAL-1 is a human uncultivable pathogen causing the sexually transmitted disease syphilis. Strain DAL-1 was isolated from the amniotic fluid of a pregnant woman in the secondary stage of syphilis. Here we describe the 1,139,971 bp long genome of T. pallidum strain DAL-1 which was sequenced using two independent sequencing methods (454 pyrosequencing and Illumina). In rabbits, strain DAL-1 replicated better than the T. pallidum strain Nichols. The comparison of the complete DAL-1 genome sequence with the Nichols sequence revealed a list of genetic differences that are potentially responsible for the increased rabbit virulence of the DAL-1 strain. PMID:23449808

Zobaníková, Marie; Mikolka, Pavol; ?ejková, Darina; Pospíšilová, Petra; Chen, Lei; Strouhal, Michal; Qin, Xiang; Weinstock, George M.; Šmajs, David

2012-01-01

17

Dendritic Cells Phagocytose and Are Activated by Treponema pallidum  

PubMed Central

Cell-mediated immune processes play a prominent role in the clinical manifestations of syphilis, a sexually transmitted disease of humans caused by spirochetal bacterium Treponema pallidum. The immune cell type that initiates the early immune response to T. pallidum thus far has not been identified. However, dendritic cells (DCs) are the first immune-competent cells to encounter antigens within skin or mucous membranes, the principal sites of early syphilitic infection. In the present study, immature DC line XS52, derived from murine skin, was utilized to examine T. pallidum-DC interactions and subsequent DC activation (maturation). Electron microscopy revealed that T. pallidum was engulfed by DCs via both coiling and conventional phagocytosis and was delivered to membrane-bound vacuoles. The XS52 DC line expressed surface CD14 and mRNA for Toll-like receptors 2 and 4, molecules comprising important signaling components for immune cell activation by bacterial modulins. Both T. pallidum and a synthetic lipopeptide (corresponding to the 47-kDa major membrane lipoprotein) activated the XS52 DC line, as indicated by the secretion of interleukin-12 (IL-12), IL-1?, tumor necrosis factor alpha, and IL-6 and elevated surface expression of CD54. The combined data support the contention that DCs stimulated by T. pallidum and/or its proinflammatory membrane lipoproteins are involved in driving the cellular immune processes that typify syphilis. PMID:11119545

Bouis, Deborah A.; Popova, Taissia G.; Takashima, Akira; Norgard, Michael V.

2001-01-01

18

Antibody  

NSDL National Science Digital Library

Antibody: A blood protein that is produced in response to and counteracts an antigen. Antibodies are produced in response to disease and help the body fight against the particular disease. In this way, antibodies help the body develop an immunity to disease.

Darryl Leja (National Human Genome Research Institute REV)

2005-04-04

19

Lipid modification of the 17-kilodalton membrane immunogen of Treponema pallidum determines macrophage activation as well as amphiphilicity.  

PubMed Central

A murine monoclonal antibody specific for a 17-kDa major membrane immunogen of Treponema pallidum was used to select recombinant Escherichia coli clones expressing the molecule from a T. pallidum genomic library. Sequence analysis of the structural gene for the immunogen (designated tpp17) revealed a 468-bp open reading frame encoding a polypeptide of 156 amino acids with a calculated molecular mass of 16,441 Da. The deduced amino acid sequence included a putative leader peptide terminated by a consensus tetrapeptide for the modification and processing of prokaryotic lipoproteins. Immunoprecipitation of the cloned immunogen radiolabeled with [3H]palmitate confirmed that it was a lipoprotein. The amino acid sequence also predicted that the mature protein contains four cysteine residues in addition to the lipid-modified cysteine of the N terminus. The existence of disulfide-bonded multimeric forms of the native immunogen was demonstrated by immunoblotting T. pallidum solubilized in the presence and absence of 2-mercaptoethanol. Triton X-114 phase partitioning of a nonlipidated form of the 17-kDa immunogen cleaved from a glutathione S-transferase fusion protein demonstrated that lipid modification is responsible for the immunogen's hydrophobic character. The same nonlipidated form of the immunogen also was used to demonstrate that lipid modification is essential for the molecule's ability to stimulate production of tumor necrosis factor alpha by murine macrophages. We conclude that covalently attached fatty acids not only anchor T. pallidum lipoproteins to spirochetal membranes but also confer upon these molecules the ability to activate immune effector cells. Images PMID:8454324

Akins, D R; Purcell, B K; Mitra, M M; Norgard, M V; Radolf, J D

1993-01-01

20

Genetic diversity in Treponema pallidum: implications for pathogenesis, evolution and molecular diagnostics of syphilis and yaws  

PubMed Central

Pathogenic uncultivable treponemes, similar to syphilis-causing Treponema pallidum subspecies pallidum, include T. pallidum ssp. pertenue, T. pallidum ssp. endemicum and Treponema carateum, which cause yaws, bejel and pinta, respectively. Genetic analyses of these pathogens revealed striking similarity among these bacteria and also a high degree of similarity to the rabbit pathogen, T. paraluiscuniculi, a treponeme not infectious to humans. Genome comparisons between pallidum and non-pallidum treponemes revealed genes with potential involvement in human infectivity, whereas comparisons between pallidum and pertenue treponemes identified genes possibly involved in the high invasivity of syphilis treponemes. Genetic variability within syphilis strains is considered as the basis of syphilis molecular epidemiology with potential to detect more virulent strains, whereas genetic variability within a single strain is related to its ability to elude the immune system of the host. Genome analyses also shed light on treponemal evolution and on chromosomal targets for molecular diagnostics of treponemal infections. PMID:22198325

Šmajs, David; Norris, Steven J.; Weinstock, George M.

2013-01-01

21

Whole Genome Sequence of Treponema pallidum ssp. pallidum, Strain Mexico A, Suggests Recombination between Yaws and Syphilis Strains  

PubMed Central

Background Treponema pallidum ssp. pallidum (TPA), the causative agent of syphilis, and Treponema pallidum ssp. pertenue (TPE), the causative agent of yaws, are closely related spirochetes causing diseases with distinct clinical manifestations. The TPA Mexico A strain was isolated in 1953 from male, with primary syphilis, living in Mexico. Attempts to cultivate TPA Mexico A strain under in vitro conditions have revealed lower growth potential compared to other tested TPA strains. Methodology/Principal Findings The complete genome sequence of the TPA Mexico A strain was determined using the Illumina sequencing technique. The genome sequence assembly was verified using the whole genome fingerprinting technique and the final sequence was annotated. The genome size of the Mexico A strain was determined to be 1,140,038 bp with 1,035 predicted ORFs. The Mexico A genome sequence was compared to the whole genome sequences of three TPA (Nichols, SS14 and Chicago) and three TPE (CDC-2, Samoa D and Gauthier) strains. No large rearrangements in the Mexico A genome were found and the identified nucleotide changes occurred most frequently in genes encoding putative virulence factors. Nevertheless, the genome of the Mexico A strain, revealed two genes (TPAMA_0326 (tp92) and TPAMA_0488 (mcp2-1)) which combine TPA- and TPE- specific nucleotide sequences. Both genes were found to be under positive selection within TPA strains and also between TPA and TPE strains. Conclusions/Significance The observed mosaic character of the TPAMA_0326 and TPAMA_0488 loci is likely a result of inter-strain recombination between TPA and TPE strains during simultaneous infection of a single host suggesting horizontal gene transfer between treponemal subspecies. PMID:23029591

P?trošová, Helena; Zobaníková, Marie; ?ejková, Darina; Mikalová, Lenka; Pospíšilová, Petra; Strouhal, Michal; Chen, Lei; Qin, Xiang; Muzny, Donna M.; Weinstock, George M.; Šmajs, David

2012-01-01

22

Evaluation of a PCR Test for Detection of Treponema pallidum in Swabs and Blood  

PubMed Central

Syphilis diagnosis is based on clinical observation, serological analysis, and dark-field microscopy (DFM) detection of Treponema pallidum subsp. pallidum, the etiological agent of syphilis, in skin ulcers. We performed a nested PCR (nPCR) assay specifically amplifying the tpp47 gene of T. pallidum from swab and blood specimens. We studied a cohort of 294 patients with suspected syphilis and 35 healthy volunteers. Eighty-seven of the 294 patients had primary syphilis, 103 had secondary syphilis, 40 had latent syphilis, and 64 were found not to have syphilis. The T. pallidum nPCR results for swab specimens were highly concordant with syphilis diagnosis, with a sensitivity of 82% and a specificity of 95%. Reasonable agreement was observed between the results obtained with the nPCR and DFM methods (kappa = 0.53). No agreement was found between the nPCR detection of T. pallidum in blood and the diagnosis of syphilis, with sensitivities of 29, 18, 14.7, and 24% and specificities of 96, 92, 93, and 97% for peripheral blood mononuclear cell (PBMC), plasma, serum, and whole-blood fractions, respectively. HIV status did not affect the frequency of T. pallidum detection in any of the specimens tested. Swab specimens from mucosal or skin lesions seemed to be more useful than blood for the efficient detection of the T. pallidum genome and, thus, for the diagnosis of syphilis. PMID:22219306

Grange, P. A.; Gressier, L.; Dion, P. L.; Farhi, D.; Benhaddou, N.; Gerhardt, P.; Morini, J. P.; Deleuze, J.; Pantoja, C.; Bianchi, A.; Lassau, F.; Avril, M. F.; Janier, M.

2012-01-01

23

Pulse radiolysis studies on superoxide reductase from Treponema pallidum  

E-print Network

Superoxide reductases (SORs) are small metalloenzymes, which catalyze reduction of O2*- to H2O2. The reaction of the enzyme from Treponema pallidum with superoxide was studied by pulse radiolysis methods. The first step is an extremely fast bi-molecular reaction of the ferrous center with O2, with a rate constant of 6 x 10 (8) M(-1) s(-1). A first intermediate is formed which is converted to a second one with a slower rate constant of 4800 s(-1). This latter value is 10 times higher than the corresponding one previously reported in the case of SOR from Desulfoarculus baarsii. The reconstituted spectra for the two intermediates are consistent with formation of transient iron-peroxide species.

Nivičre, V; Fontecave, M; Houée-Levin, C

2015-01-01

24

Fibronectin binding to the Treponema pallidum adhesin protein fragment rTp0483 on functionalized self-assembled monolayers.  

PubMed

Past work has shown that Treponema pallidum, the causative agent of syphilis, binds host fibronectin (FN). FN and other host proteins are believed to bind to rare outer membrane proteins (OMPs) of T. pallidum, and it is postulated that this interaction may facilitate cell attachment and mask antigenic targets on the surface. This research seeks to prepare a surface capable of mimicking the FN binding ability of T. pallidum in order to investigate the impact of FN binding with adsorbed Tp0483 on the host response to the surface. By understanding this interaction, it may be possible to develop more effective treatments for infection and possibly mimic the stealth properties of the bacteria. Functionalized self-assembled monolayers (SAMs) on gold were used to investigate rTp0483 and FN adsorption. Using a quartz crystal microbalance (QCM), rTp0483 adsorption and subsequent FN adsorption onto rTp0483 were determined to be higher on negatively charged carboxylate-terminated self-assembled monolayers (-COO(-) SAMs) compared to the other surfaces analyzed. Kinetic analysis of rTp0483 adsorption using surface plasmon resonance (SPR) supported this finding. Kinetic analysis of FN adsorption using SPR revealed a multistep event, where the concentration of immobilized rTp0483 plays a role in FN binding. An examination of relative QCM dissipation energy compared to the shift in frequency showed a correlation between the physical properties of adsorbed rTp0483 and SAM surface chemistry. In addition, AFM images of rTp0483 on selected SAMs illustrated a preference of rTp0483 to bind as aggregates. Adsorption on -COO(-) SAMs was more uniform across the surface, which may help further explain why FN bound more strongly. rTp0483 antibody studies suggested the involvement of amino acids 274-289 and 316-333 in binding between rTp0483 to FN, while a peptide blocking study only showed inhibition of binding with amino acids 316-333. Finally, surface adsorbed rTp0483 with FN bound significantly less anti-RGD and gelatin compared to FN adsorbed directly to -COO(-) SAMs, indicating that one or both binding regions may play a role in binding between rTp0483 and FN. PMID:22175441

Dickerson, Matthew T; Abney, Morgan B; Cameron, Caroline E; Knecht, Marc; Bachas, Leonidas G; Anderson, Kimberly W

2012-02-15

25

Molecular cloning and DNA sequence analysis of the 37-kilodalton endoflagellar sheath protein gene of Treponema pallidum.  

PubMed Central

We have used a combination of nucleotide and N-terminal-amino-acid-sequence analyses to determine the primary structure of the 37-kilodalton (kDa) endoflagellar outer layer, or sheath, protein. Initially, a lambda gt11 clone (designated lambda A34) expressing a portion of the 37-kDa protein was selected from a Treponema pallidum genomic library with a murine monoclonal antibody (H9-2) directed against an epitope of the 37-kDa protein. The insert from lambda A34 provided a probe with which a chimeric plasmid (pR14) encoding all but the nine N-terminal amino acids of the entire protein was selected from a T. pallidum(pBR322) genomic library. The nine N-terminal amino acids determined by amino acid sequencing were combined with the DNA sequence encoded by pR14 to determine the primary structure of the entire 37-kDa protein; the combined sequence made up a polypeptide with a calculated molecular mass of 36,948 Da. Approximately one-third of the deduced sequence was confirmed by N-terminal amino acid analysis of tryptic peptides from the purified 37-kDa protein. Repeated attempts to clone upstream portions of the gene (flaA) by using a variety of strategies were unsuccessful, suggesting that unregulated expression of the intact sheath protein or of its most amino-terminal portions is toxic in Escherichia coli. These studies should provide the basis for further molecular investigations of the endoflagellar apparatus and of treponemal motility. Images PMID:2680972

Isaacs, R D; Hanke, J H; Guzman-Verduzco, L M; Newport, G; Agabian, N; Norgard, M V; Lukehart, S A; Radolf, J D

1989-01-01

26

Genome Analysis of Treponema pallidum subsp. pallidum and subsp. pertenue Strains: Most of the Genetic Differences Are Localized in Six Regions  

PubMed Central

The genomes of eight treponemes including T. p. pallidum strains (Nichols, SS14, DAL-1 and Mexico A), T. p. pertenue strains (Samoa D, CDC-2 and Gauthier), and the Fribourg-Blanc isolate, were amplified in 133 overlapping amplicons, and the restriction patterns of these fragments were compared. The approximate sizes of the genomes investigated based on this whole genome fingerprinting (WGF) analysis ranged from 1139.3–1140.4 kb, with the estimated genome sequence identity of 99.57–99.98% in the homologous genome regions. Restriction target site analysis, detecting the presence of 1773 individual restriction sites found in the reference Nichols genome, revealed a high genome structure similarity of all strains. The unclassified simian Fribourg-Blanc isolate was more closely related to T. p. pertenue than to T. p. pallidum strains. Most of the genetic differences between T. p. pallidum and T. p. pertenue strains were accumulated in six genomic regions. These genome differences likely contribute to the observed differences in pathogenicity between T. p. pallidum and T. p. pertenue strains. These regions of sequence divergence could be used for the molecular detection and discrimination of syphilis and yaws strains. PMID:21209953

Mikalová, Lenka; Strouhal, Michal; ?ejková, Darina; Zobaníková, Marie; Pospíšilová, Petra; Norris, Steven J.; Sodergren, Erica; Weinstock, George M.; Šmajs, David

2010-01-01

27

Use of Treponema pallidum PCR in Testing of Ulcers for Diagnosis of Primary Syphilis1  

PubMed Central

Treponema pallidum PCR (Tp-PCR) has been noted as a valid method for diagnosing syphilis. We compared Tp-PCR to a combination of darkfield microscopy (DFM), the reference method, and serologic testing in a cohort of 273 patients from France and Switzerland and found the diagnostic accuracy of Tp-PCR was higher than that for DFM. PMID:25531672

Sednaoui, Patrice; Lautenschlager, Stephan; Ferry, Tristan; Toutous-Trellu, Laurence; Cavassini, Matthias; Yassir, Fatima; Martinez de Tejada, Begońa; Emonet, Stéphane; Combescure, Christophe; Schrenzel, Jacques; Perneger, Thomas

2015-01-01

28

Use of Treponema pallidum PCR in Testing of Ulcers for Diagnosis of Primary Syphilis(1.).  

PubMed

Treponema pallidum PCR (Tp-PCR) has been noted as a valid method for diagnosing syphilis. We compared Tp-PCR to a combination of darkfield microscopy (DFM), the reference method, and serologic testing in a cohort of 273 patients from France and Switzerland and found the diagnostic accuracy of Tp-PCR was higher than that for DFM. PMID:25531672

Gayet-Ageron, Angčle; Sednaoui, Patrice; Lautenschlager, Stephan; Ferry, Tristan; Toutous-Trellu, Laurence; Cavassini, Matthias; Yassir, Fatima; Martinez de Tejada, Begońa; Emonet, Stéphane; Combescure, Christophe; Schrenzel, Jacques; Perneger, Thomas

2015-01-01

29

Treponema pallidum Infection in the Wild Baboons of East Africa: Distribution and Genetic Characterization of the Strains Responsible  

PubMed Central

It has been known for decades that wild baboons are naturally infected with Treponema pallidum, the bacterium that causes the diseases syphilis (subsp. pallidum), yaws (subsp. pertenue), and bejel (subsp. endemicum) in humans. Recently, a form of T. pallidum infection associated with severe genital lesions has been described in wild baboons at Lake Manyara National Park in Tanzania. In this study, we investigated ten additional sites in Tanzania and Kenya using a combination of macroscopic observation and serology, in order to determine whether the infection was present in each area. In addition, we obtained genetic sequence data from six polymorphic regions using T. pallidum strains collected from baboons at two different Tanzanian sites. We report that lesions consistent with T. pallidum infection were present at four of the five Tanzanian sites examined, and serology was used to confirm treponemal infection at three of these. By contrast, no signs of treponemal infection were observed at the six Kenyan sites, and serology indicated T. pallidum was present at only one of them. A survey of sexually mature baboons at Lake Manyara National Park in 2006 carried out as part of this study indicated that roughly ten percent displayed T. pallidum-associated lesions severe enough to cause major structural damage to the genitalia. Finally, we found that T. pallidum strains from Lake Manyara National Park and Serengeti National Park were genetically distinct, and a phylogeny suggested that baboon strains may have diverged prior to the clade containing human strains. We conclude that T. pallidum infection associated with genital lesions appears to be common in the wild baboons of the regions studied in Tanzania. Further study is needed to elucidate the infection's transmission mode, its associated morbidity and mortality, and the relationship between baboon and human strains. PMID:23284649

Harper, Kristin N.; Fyumagwa, Robert D.; Hoare, Richard; Wambura, Philemon N.; Coppenhaver, Dorian H.; Sapolsky, Robert M.; Alberts, Susan C.; Tung, Jenny; Rogers, Jeffrey; Kilewo, Morris; Batamuzi, Emmanuel K.; Leendertz, Fabian H.; Armelagos, George J.; Knauf, Sascha

2012-01-01

30

Evaluation of the Recombinant Protein TpF1 of Treponema pallidum for Serodiagnosis of Syphilis  

PubMed Central

Syphilis is a chronic infection caused by Treponema pallidum subsp. pallidum, and diagnosis with sensitive and specific methods is a challenging process that is important for its prevention and treatment. In the present study, we established a recombinant protein TpF1-based indirect immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) and a Western blot assay for human and rabbit sera. The 20-kDa recombinant protein TpF1 was detected by Western blotting performed with sera from rabbits immunized with recombinant TpF1 and infected with the T. pallidum Nichols strain and T. pallidum clinical isolates but was not detected by Western blotting with sera from uninfected rabbits. The sensitivity of the recombinant protein was determined by screening sera from individuals with primary, secondary, latent, and congenital syphilis (n = 82). The specificity of the recombinant protein was determined by screening sera from uninfected controls (n = 30) and individuals with potentially cross-reactive infections, including Lyme disease (n = 30) and leptospirosis (n = 5). The sensitivities of TpF1-based ELISAs were 93.3%, 100%, 100%, and 100% for primary, secondary, latent, and congenital syphilis, respectively, and the specificities were all 100% for sera from uninfected controls and individuals with potentially cross-reactive infections. In Western blot assays, the sensitivities and specificities of TpF1 for human sera were all 100%. The reactivities of TpF1 with syphilitic sera were proportional to the titers of the T. pallidum particle agglutination (TPPA) assay. These data indicate that the recombinant protein TpF1 is a highly immunogenic protein in human and rabbit infections and a promising marker for the screening of syphilis. PMID:23945159

Jiang, Chuanhao; Zhao, Feijun; Xiao, Jinhong; Zeng, Tiebing; Yu, Jian; Ma, Xiaohua; Wu, Haiying

2013-01-01

31

Performance Evaluation of the Elecsys Syphilis Assay for the Detection of Total Antibodies to Treponema pallidum  

PubMed Central

Syphilis is a health problem of increasing incidence in recent years that may have severe complications if not diagnosed and treated at an early stage. There are many diagnostic tests available for syphilis, but there is no gold standard, and diagnosis therefore usually relies upon a combination of tests. In this multicenter study, we evaluated the treponemal Elecsys syphilis assay for use in the diagnosis of syphilis in routine samples, i.e., when syphilis is suspected or during antenatal or blood donation screening. The sensitivity and specificity of the Elecsys syphilis assay were compared head to head with those of other treponemal assays used in routine clinical practice and were assessed in potentially cross-reactive samples from patients with Epstein-Barr virus, HIV, and Lyme disease. In a total of 8,063 syphilis-negative samples collected from routine diagnostic requests and blood donations, the Elecsys syphilis assay had a specificity of 99.88%. In 928 samples previously identified as syphilis positive, the sensitivity was 99.57 to 100% (the result is presented as a range depending on whether four initially indeterminate samples are included in the assessment). The specificity of the Elecsys syphilis assay in patients with other infections was 100%; no false-positive samples were identified. PMID:25355799

Enders, Martin; Hunjet, Andrea; Gleich, Michael; Imdahl, Roland; Mühlbacher, Annelies; Schennach, Harald; Chaiwong, Kriangsak; Sakuldamrongpanich, Tasanee; Turhan, Ajda; Sertöz, Rüchan; Wolf, Eva; Mayer, Wolfgang; Tao, Chuanmin; Wang, Lan Lan; Semprini, Simona

2014-01-01

32

Performance Evaluation of the Elecsys Syphilis Assay for the Detection of Total Antibodies to Treponema pallidum.  

PubMed

Syphilis is a health problem of increasing incidence in recent years that may have severe complications if not diagnosed and treated at an early stage. There are many diagnostic tests available for syphilis, but there is no gold standard, and diagnosis therefore usually relies upon a combination of tests. In this multicenter study, we evaluated the treponemal Elecsys syphilis assay for use in the diagnosis of syphilis in routine samples, i.e., when syphilis is suspected or during antenatal or blood donation screening. The sensitivity and specificity of the Elecsys syphilis assay were compared head to head with those of other treponemal assays used in routine clinical practice and were assessed in potentially cross-reactive samples from patients with Epstein-Barr virus, HIV, and Lyme disease. In a total of 8,063 syphilis-negative samples collected from routine diagnostic requests and blood donations, the Elecsys syphilis assay had a specificity of 99.88%. In 928 samples previously identified as syphilis positive, the sensitivity was 99.57 to 100% (the result is presented as a range depending on whether four initially indeterminate samples are included in the assessment). The specificity of the Elecsys syphilis assay in patients with other infections was 100%; no false-positive samples were identified. PMID:25355799

Enders, Martin; Hunjet, Andrea; Gleich, Michael; Imdahl, Roland; Mühlbacher, Annelies; Schennach, Harald; Chaiwong, Kriangsak; Sakuldamrongpanich, Tasanee; Turhan, Ajda; Sertöz, Rüchan; Wolf, Eva; Mayer, Wolfgang; Tao, Chuanmin; Wang, Lan Lan; Semprini, Simona; Sambri, Vittorio

2015-01-01

33

Detection by polymerase chain reaction of Treponema pallidum DNA in cerebrospinal fluid from neurosyphilis patients before and after antibiotic treatment.  

PubMed Central

A polymerase chain reaction with nested primer pairs based on the DNA sequence of the 39-kDa bmp gene of Treponema pallidum subsp. pallidum is described. The method allowed the detection of purified T. pallidum DNA equivalent to the amount of DNA in a single bacterium and was specific for T. pallidum subspecies. After concentration of DNA, using diatomaceous earth, it was possible to detect about 100 treponemes in 1 ml of cerebrospinal fluid. Cerebrospinal fluid samples from a total of 29 symptomatic and asymptomatic patients with neurosyphilis were tested for the presence of treponemal DNA before and at various intervals after intravenous treatment with penicillin. Prior to the penicillin treatment, we detected T. pallidum DNA in 5 of 7 patients with acute symptomatic neurosyphilis, in none of the 4 patients with chronic symptomatic neurosyphilis tested before treatment, and in 2 of 16 patients with asymptomatic neurosyphilis. Unexpectedly, T. pallidum DNA was also often detected in cerebrospinal fluid long after intervenous treatment with penicillin, sometimes up to 3 years after therapy. Images PMID:1774324

Noordhoek, G T; Wolters, E C; de Jonge, M E; van Embden, J D

1991-01-01

34

HIV, HBV, HCV and T. pallidum infections among blood donors and Transfusion-related complications among recipients at the Laquintinie hospital in Douala, Cameroon  

PubMed Central

Background Transfusion-transmissible infections (TTIs) pose a major health risk in Cameroon given the high prevalence of such pathogens and increased demands for blood donations in the local communities. This study aims at establishing the prevalence of commonly encountered TTIs among blood donors and transfusion-related complications among recipients in an urban center of Cameroon. Methods A total of 477 blood donors and 83 blood recipients were recruited by consecutive sampling at the Laquintinie Hospital in Douala (LHD), Cameroon. Serum samples from blood donors were tested by quantitative enzyme-linked immunosorbent assays (ELISA) and/or using various Rapid diagnostic test (RDT) for presence of Hepatits B (HBV) viral antigens, and antibodies to human immunodeficiency (HIV-1/2), Hepatits B (HCV) and Treponema pallidum. Recipient’s medical records were also analyzed for possible transfusion-associated complications. Results The male/female sex ratio of the blood donors was 4/1 with a mean age of 30.2 (Sd?=?8.3) years. Of all blood donors, 64/467 (13.7%) were infected by at least one of the four TTIs. Infected volunteer donors represented 8.3% while infected family donors comprised 14.3% of the donor population. The prevalence of HCV, HIV, HBV and T. pallidum were 1.3%, 1.8%, 3.5%, and 8.1%, respectively. More than half of the blood recipients were female (78.3%) and the mean age was 20.6 (SD?=?16.1) years. The causes of severe anemia indicative of transfusion in recipients varied with wards (postpartum hemorrhage, caesarean section, uterine or cervical lacerations, abortions, urinary tract infections, severe malaria, vaso-occlusive attacks, wounds and gastrointestinal bleeding). The most frequent complications were chills and hematuria, which represented 46.1% of all observed complications. Other complications such as nausea, vomiting, jaundice, sudden diarrhea, anxiety, tachycardia, or hyperthermia were also found in recipients. Three cases of deaths occurred during the study, including a girl of less than one year. Conclusion This study confirms the presence of blood-borne infectious diseases in blood donors at the LHD, identifying T. pallidum as the greatest threat to blood safety in the region, and hematuria as the most common immunological complications in blood recipients. PMID:24517107

2014-01-01

35

Clovamide-rich extract from Trifolium pallidum reduces oxidative stress-induced damage to blood platelets and plasma.  

PubMed

Numerous plants (including clovers) have been widely used in folk medicine for the treatment of different disorders. This in vitro study was designed to examine the antioxidative effects of the clovamide-rich fraction, obtained from aerial parts of Trifolium pallidum, in the protection of blood platelets and plasma against the nitrative and oxidative damage, caused by peroxynitrite (ONOO(-)). Carbonyl groups and 3-nitrotyrosine in blood platelet and plasma proteins were determined by ELISA tests. Thiol groups level was estimated by using 5,5'-dithio-bis(2-nitro-benzoic acid, DTNB). Plasma lipid peroxidation was measured spectrophotometrically as the production of thiobarbituric acid reactive substances. The results from our work indicate that clovamide-rich T. pallidum extract may reveal the protective properties in the prevention against oxidative stress. The presence of clovamide-rich T. pallidum extract (12.5-100 ?g/ml) partly inhibited ONOO(-)-mediated protein carbonylation and nitration. All the used concentrations of T. pallidum extract reduced lipid peroxidation in plasma. The antioxidative action of the tested extract in the protection of blood platelet lipids was less effective; the extract at the lowest final concentration (12.5 ?g/ml) had no protective effect against lipid peroxidation. The present results indicate that the extract from T. pallidum is likely to be a source of compounds with the antioxidative properties, useful in the prevention against the oxidative stress-related diseases. PMID:21465272

Kolodziejczyk, Joanna; Olas, Beata; Wachowicz, Barbara; Szajwaj, Barbara; Stochmal, Anna; Oleszek, Wieslaw

2011-09-01

36

Molecular Differentiation of Treponema pallidum Subspecies in Skin Ulceration Clinically Suspected as Yaws in Vanuatu Using Real-Time Multiplex PCR and Serological Methods.  

PubMed

We developed a TaqMan-based real-time quadriplex polymerase chain reaction (PCR) to simultaneously detect Treponema pallidum subspecies pallidum, T. pallidum subsp. pertenue, and T. pallidum subsp. endemicum, the causative agents of venereal syphilis, yaws, and bejel, respectively. The PCR assay was applied to samples from skin ulcerations of clinically presumptive yaws cases among children on Tanna Island, Vanuatu. Another real-time triplex PCR was used to screen for the point mutations in the 23S rRNA genes that have previously been associated with azithromycin resistance in T. pallidum subsp. pallidum strains. Seropositivity by the classical syphilis serological tests was 35.5% among children with skin ulcerations clinically suspected with yaws, whereas the presence of T. pallidum subsp. pertenue DNA was only found in lesions from 15.5% of children. No evidence of T. pallidum subsp. pertenue infection, by either PCR or serology was found in ?59% of cases indicating alternative causes of yaws-like lesions in this endemic area. PMID:25404075

Chi, Kai-Hua; Danavall, Damien; Taleo, Fasihah; Pillay, Allan; Ye, Tun; Nachamkin, Eli; Kool, Jacob L; Fegan, David; Asiedu, Kingsley; Vestergaard, Lasse S; Ballard, Ronald C; Chen, Cheng-Yen

2015-01-01

37

Purification, crystallization and preliminary X-ray analysis of TP0435 (Tp17) from the syphilis spirochete Treponema pallidum  

PubMed Central

Syphilis, caused by the bacterial spirochete Treponema pallidum, remains a prominent sexually transmitted infection worldwide. Despite sequencing of the genome of this obligate human pathogen 15 years ago, the functions of a large number of the gene products of T. pallidum are still unknown, particularly with respect to those of the organism’s periplasmic lipoproteins. To better understand their functions, a structural biology approach has been pursued. To this end, the soluble portion of the T. pallidum TP0435 lipoprotein (also known as Tp17) was cloned, hyper-expressed in Escherichia coli and purified to apparent homogeneity. The protein crystals obtained from this preparation diffracted to 2.4?Ĺ resolution and had the symmetry of space group R3. In the hexagonal setting, the unit-cell parameters were a = b = 85.7, c = 85.4?Ĺ. PMID:23545658

Brautigam, Chad A.; Deka, Ranjit K.; Norgard, Michael V.

2013-01-01

38

Amides and esters of phenylpropenoic acids from the aerial parts of Trifolium pallidum.  

PubMed

Two new derivatives of phenylpropenoic acids, N-trans-feruloyl-L-DOPA and O-trans-caffeoyl-malic acid dimethyl ester, along with four known N-trans-caffeoyl-L-DOPA (clovamide), N-trans-caffeoyl-L-DOPA-methyl ester, O-trans-caffeoyl-malic acid, O-trans-feruloyl-malic acid and quercetin 3-O-beta-D-glucopyranoside were isolated from the aerial parts of Trifolium pallidum. Their structures were elucidated by extensive spectroscopic methods including 1D- (1H, 13C) and 2D-NMR (DQF-COSY, HSQC, HMBC) experiments as well as mass spectrometry analysis. PMID:21941901

Szajwaj, Barbara; Moldoch, Jaroslaw; Masullo, Milena; Piacente, Sonia; Oleszek, Wieslaw; Stochmal, Anna

2011-09-01

39

[Biological activity of lipids and photosynthetic pigments of Sargassum pallidum C. Agardh].  

PubMed

The biological activity of lipids and photosynthetic pigments of the kelp Sargassum pallidum (Turner) C. Agardh has been studied. Free fatty acids and their esters demonstrated considerable antimicrobial activity against bacteria (Staphylococcus aureus[ital] and Escherichia coli), yeast-like fungi (Candida albicans), and opportunistic pathogenic (Aspergilius niger) and phytopathogenic (Fusarium oxysporum, and Septoria glycines) fungi. Glyceroglycolipids and neutral lipids demonstrated moderate activity. Fucoxanthin and chlorophylls weakly suppressed the growth of microorganisms. None of the studied substances demonstrated activity against Ehrlich's carcinoma. It was shown that the season of weed harvesting affected both antimicrobial and hemolytic activities of different lipids due to changes in their fatty acid composition. PMID:25272757

Gerasimenko, N I; Martyias, E A; Logvinov, S V; Busarova, N G

2014-01-01

40

Identification and purification of an endogenous receptor for the lectin pallidin from Polysphondylium pallidum  

PubMed Central

We report the identification and purification of an endogenous carbohydrate-containing receptor of pallidin, the cell surface lectin implicated in mediating cell-cell adhesion in the cellular slime mold Polysphondylium pallidum. The receptor is identified in an aqueous extract of crude P. pallidum membranes as a potent inhibitor of the hemagglutination activity of pallidin. The inhibitor is purified to apparent homogeneity by affinity precipitation with pallidin followed by fractionation of the solubilized precipitate on Sepharose 4B. The hemagglutination inhibitor (HAI) is metabolically radiolabeled, indicating that it is a biosynthetic product of the amoebae and not an ingested food substance. The HAI is released into the extracellular medium by living, differentiated amoebae. This release is markedly facilitated by the addition of D-galactose, a specific saccharide that binds to pallidin. Hence, the HAI appears to have an in situ association with pallidin at the cell surface. Exogenously added HAI promotes the agglutination of differentiated amoebae in a gyrated suspension at very low concentrations. The results are consistent with a model of cell-cell adhesion in which the HAI is a multivalent, extracellular aggregation factor that is recognized by pallidin molecules on adjacent cells. The HAI would then be analogues to the aggregation factors identified in marine sponges. PMID:6896517

1982-01-01

41

Structural, Bioinformatic, and In Vivo Analyses of Two Treponema pallidum Lipoproteins Reveal a Unique TRAP Transporter  

SciTech Connect

Treponema pallidum, the bacterial agent of syphilis, is predicted to encode one tripartite ATP-independent periplasmic transporter (TRAP-T). TRAP-Ts typically employ a periplasmic substrate-binding protein (SBP) to deliver the cognate ligand to the transmembrane symporter. Herein, we demonstrate that the genes encoding the putative TRAP-T components from T. pallidum, tp0957 (the SBP), and tp0958 (the symporter), are in an operon with an uncharacterized third gene, tp0956. We determined the crystal structure of recombinant Tp0956; the protein is trimeric and perforated by a pore. Part of Tp0956 forms an assembly similar to those of 'tetratricopeptide repeat' (TPR) motifs. The crystal structure of recombinant Tp0957 was also determined; like the SBPs of other TRAP-Ts, there are two lobes separated by a cleft. In these other SBPs, the cleft binds a negatively charged ligand. However, the cleft of Tp0957 has a strikingly hydrophobic chemical composition, indicating that its ligand may be substantially different and likely hydrophobic. Analytical ultracentrifugation of the recombinant versions of Tp0956 and Tp0957 established that these proteins associate avidly. This unprecedented interaction was confirmed for the native molecules using in vivo cross-linking experiments. Finally, bioinformatic analyses suggested that this transporter exemplifies a new subfamily of TPATs (TPR-protein-associated TRAP-Ts) that require the action of a TPR-containing accessory protein for the periplasmic transport of a potentially hydrophobic ligand(s).

Deka, Ranjit K.; Brautigam, Chad A.; Goldberg, Martin; Schuck, Peter; Tomchick, Diana R.; Norgard, Michael V. (NIH); (UTSMC)

2012-05-25

42

Designer Receptors Show Role for Ventral Pallidum Input to Ventral Tegmental Area in Cocaine Seeking  

PubMed Central

Ventral pallidum (VP) is centrally positioned within mesocorticolimbic reward circuits, and its dense projection to ventral tegmental area (VTA) regulates neuronal activity there. However, VP is a heterogeneous structure, and how this complexity affects its role within wider reward circuits is unclear. Here we demonstrate that projections to VTA from rostral (RVP), but not caudal VP (CVP) are robustly Fos-activated during cue-induced reinstatement of cocaine seeking—a rat model of relapse in addiction. Moreover, designer receptor-mediated transient inactivation of RVP neurons, their terminals in VTA, or functional connectivity between RVP and VTA dopamine neurons blocks the ability of drug-associated cues (but not a cocaine prime) to reinstate cocaine seeking. In contrast, CVP neuronal inhibition instead blocked cocaine-primed, but not cue-induced reinstatement. This novel double dissociation in VP sub-regional roles in drug seeking is likely important for understanding mesocorticolimbic circuits underlying reward seeking and addiction. PMID:24584054

Mahler, Stephen V.; Vazey, Elena M.; Beckley, Jacob T; Keistler, Colby R.; McGlinchey, Ellen M.; Kaufling, Jennifer; Wilson, Steven P.; Deisseroth, Karl; Woodward, John J.; Aston-Jones, Gary

2014-01-01

43

Changes in glucan synthetase activity and plasma membrane proteins during encystment of the cellular slime mold Polysphondylium pallidum  

Microsoft Academic Search

The activity of glucan synthetase increased dramatically during encystment of Polysphondylium pallidum cells. The majority of activity was present in purified plasma membranes. Activity, measured as glucose incorporation from UDPG into NaOH-insoluble glucan, increased 30–40 fold in the membranes. Increases in activity within the cells preceded plasma membrane increases and the enzyme appeared to be rapidly transported to the plasma

M. L. Philippi; Roger W. Parish

1981-01-01

44

Excessive disgust caused by brain lesions or temporary inactivations: mapping hotspots of the nucleus accumbens and ventral pallidum.  

PubMed

Disgust is a prototypical type of negative affect. In animal models of excessive disgust, only a few brain sites are known in which localized dysfunction (lesions or neural inactivations) can induce intense 'disgust reactions' (e.g. gapes) to a normally pleasant sensation such as sweetness. Here, we aimed to map forebrain candidates more precisely, to identify where either local neuronal damage (excitotoxin lesions) or local pharmacological inactivation (muscimol/baclofen microinjections) caused rats to show excessive sensory disgust reactions to sucrose. Our study compared subregions of the nucleus accumbens shell, ventral pallidum, lateral hypothalamus, and adjacent extended amygdala. The results indicated that the posterior half of the ventral pallidum was the only forebrain site where intense sensory disgust gapes in response to sucrose were induced by both lesions and temporary inactivations (this site was previously identified as a hedonic hotspot for enhancements of sweetness 'liking'). By comparison, for the nucleus accumbens, temporary GABA inactivations in the caudal half of the medial shell also generated sensory disgust, but lesions never did at any site. Furthermore, even inactivations failed to induce disgust in the rostral half of the accumbens shell (which also contains a hedonic hotspot). In other structures, neither lesions nor inactivations induced disgust as long as the posterior ventral pallidum remained spared. We conclude that the posterior ventral pallidum is an especially crucial hotspot for producing excessive sensory disgust by local pharmacological/lesion dysfunction. By comparison, the nucleus accumbens appears to segregate sites for pharmacological disgust induction and hedonic enhancement into separate posterior and rostral halves of the medial shell. PMID:25229197

Ho, Chao-Yi; Berridge, Kent C

2014-11-01

45

Recombinant Treponema pallidum Protein Tp0965 Activates Endothelial Cells and Increases the Permeability of Endothelial Cell Monolayer  

PubMed Central

The recombinant Treponema pallidum protein Tp0965 (rTp0965), one of the many proteins derived from the genome of T. pallidum subsp. pallidum, shows strong immunogenicity and immunoreactivity. In this study, we investigated the effects of rTp0965 on the endothelial barrier. Treatment of human umbilical vein endothelial cells (HUVECs) with rTp0965 resulted in increased levels of ICAM-1, E-selectin, and MCP-1 mRNA and protein expression. These increases contributed to the adhesion and chemataxis of monocytes (THP-1 cells) to HUVECs preincubated with rTp0965. In addition, rTp0965 induced reorganization of F-actin and decreased expression of claudin-1 in HUVECs. Interestingly, inhibition of the RhoA/ROCK signal pathway protected against rTp0965-induced higher endothelial permeability as well as transendothelial migration of monocytes. These data indicate that Tp0965 protein may play an important role in the immunopathogenesis of syphilis. PMID:25514584

Zhang, Rui-Li; Zhang, Jing-Ping; Wang, Qian-Qiu

2014-01-01

46

Biophysical and Bioinformatic Analyses Implicate the Treponema pallidum Tp34 Lipoprotein (Tp0971) in Transition Metal Homeostasis  

PubMed Central

Metal ion homeostasis is a critical function of many integral and peripheral membrane proteins. The genome of the etiologic agent of syphilis, Treponema pallidum, is compact and devoid of many metabolic enzyme genes. Nevertheless, it harbors genes coding for homologs of several enzymes that typically require either iron or zinc. The product of the tp0971 gene of T. pallidum, designated Tp34, is a periplasmic lipoprotein that is thought to be tethered to the inner membrane of this organism. Previous work on a water-soluble (nonacylated) recombinant version of Tp34 established that this protein binds to Zn2+, which, like other transition metal ions, stabilizes the dimeric form of the protein. In this study, we employed analytical ultracentrifugation to establish that four transition metal ions (Ni2+, Co2+, Cu2+, and Zn2+) readily induce the dimerization of Tp34; Cu2+ (50% effective concentration [EC50] = 1.7 ?M) and Zn2+ (EC50 = 6.2 ?M) were the most efficacious of these ions. Mutations of the crystallographically identified metal-binding residues hindered the ability of Tp34 to dimerize. X-ray crystallography performed on crystals of Tp34 that had been incubated with metal ions indicated that the binding site could accommodate the metals examined. The findings presented herein, coupled with bioinformatic analyses of related proteins, point to Tp34's likely role in metal ion homeostasis in T. pallidum. PMID:23042995

Brautigam, Chad A.; Deka, Ranjit K.; Ouyang, Zhiming; Machius, Mischa; Knutsen, Gregory; Tomchick, Diana R.

2012-01-01

47

Extracts from Trifolium pallidum and Trifolium scabrum aerial parts as modulators of blood platelet adhesion and aggregation.  

PubMed

A growing number of reports indicate that some species of clover (Trifolium) may have remarkable medical importance; however, the effects of these plants on blood platelets and hemostasis are inadequately recognized. This work was designed to study the effects of Trifolium pallidum and Trifolium scabrum extracts on the functions of human blood platelets in vitro. Platelet suspensions were preincubated with extracts from aerial parts of T. pallidum (phenolic fraction and clovamide fraction) and T. scabrum (phenolic fraction) at the final concentrations of 12.5, 25, and 50?µg/ml. Then, for platelet activation thrombin (0.1?U/ml), thrombin receptor activating peptide (TRAP; 20?µM), or adenosine diphosphate (ADP; 1?µM) were used. The effects of Trifolium extracts on adhesion of blood platelets to fibrinogen and collagen were determined by enzyme-linked immunosorbent assay (ELISA) method. Platelet aggregation was monitored on a dual-channel Chronolog aggregometer. In these studies, we also compared the action of tested plant extracts with the effects of another antiplatelet plant-derived compound - resveratrol (3,4',5-trihydroxystilbene). The performed assays demonstrated that the tested extracts might influence the platelet functions in vitro. The inhibitory, concentration-dependent effects of all tested extracts on adhesion of thrombin-stimulated platelets to collagen was found. Both extracts from T. pallidum and from T. scabrum reduced the thrombin-induced platelet adhesion to fibrinogen. Furthermore, in the presence of all three extracts, the platelet aggregation induced by thrombin was slightly inhibited. Our results also indicate that the tested plant extracts (at the highest concentrations used of 50?µg/ml), similar to purified resveratrol, inhibit selected steps of platelet activation stimulated by both proteolytic (thrombin) and nonproteolytic agonists (TRAP or ADP). In the comparative studies, T. pallidum and T. scabrum extracts was not found to be more effective antiaggregatory factor, than resveratrol. Extracts from T. pallidum and T. scabrum aerial parts reveal antiplatelet properties: the antiadhesive effect was similar to that of the reference compound resveratrol, whereas the antiaggregant effect was less marked. The results obtained suggest that these plants may be a promising source of natural compounds, valuable in the prevention of the enhanced activity of blood platelets in numerous cardiovascular diseases, observed in menopausal or postmenopausal women. PMID:22646735

Kolodziejczyk-Czepas, Joanna; Olas, Beata; Malinowska, Joanna; Wachowicz, Barbara; Szajwaj, Barbara; Kowalska, Iwona; Oleszek, Wieslaw; Stochmal, Anna

2013-01-01

48

Trifolium pallidum and Trifolium scabrum extracts in the protection of human plasma components.  

PubMed

Clovers (genus: Trifolium) have been used in traditional medicine by many cultures, but the biological activity of the most of these plants still remains unknown. The aim of our in vitro study was to assess the antioxidative action of phenolic extracts from aerial parts of Trifolium scabrum and Trifolium pallidum in human blood plasma, exposed to oxidative stress. In the present study we also demonstrate, for the first time the effects of the tested extracts on coagulative properties and fibrinolytic activity of blood plasma. The protective properties of the examined extracts (0.5-50 ?g/ml) against peroxynitrite-induced oxidative stress were estimated by the measurements of 3-nitrotyrosine, thiol groups and the thiobarbituric acid-reactive substances levels. The extracts considerably prevented the oxidative and nitrative damage to plasma proteins. Even the lowest doses of the Trifolium extracts (0.5 ?g/ml) were able to markedly reduce 3-nitrotyrosine formation (by about 50%) and to increase the level of -SH groups (by about 30%), in comparison to the plasma exposed to ONOO(-) in the absence of the extracts. The protective action of all the used concentrations of the Trifolium extracts in the prevention of lipid peroxidation was also found. The tested extracts influenced neither the coagulative properties nor fibrinolytic activity of plasma. Moreover, the extracts were able to significantly reduce the inhibitory effect of ONOO(-) on fibrinolytic activity of plasma (assessed with the use of a chromogenic substrate for plasmin). PMID:23335023

Kolodziejczyk-Czepas, Joanna; Olas, Beata; Malinowska, Joanna; Wachowicz, Barbara; Moniuszko-Szajwaj, Barbara; Kowalska, Iwona; Oleszek, Wieslaw; Stochmal, Anna

2013-02-01

49

Antithyroglobulin antibody  

MedlinePLUS

Antithyroglobulin antibody is a test to measure antibodies to a protein called thyroglobulin, which is found in ... This test helps detect possible thyroid problems. ... system. Such antibodies are more likely to appear after thyroid ...

50

Mitochondrial tRNA 5'-editing in Dictyostelium discoideum and Polysphondylium pallidum.  

PubMed

Mitochondrial tRNA (mt-tRNA) 5'-editing was first described more than 20 years ago; however, the first candidates for 5'-editing enzymes were only recently identified in a eukaryotic microbe (protist), the slime mold Dictyostelium discoideum. In this organism, eight of 18 mt-tRNAs are predicted to be edited based on the presence of genomically encoded mismatched nucleotides in their aminoacyl-acceptor stem sequences. Here, we demonstrate that mt-tRNA 5'-editing occurs at all predicted sites in D. discoideum as evidenced by changes in the sequences of isolated mt-tRNAs compared with the expected sequences encoded by the mitochondrial genome. We also identify two previously unpredicted editing events in which G-U base pairs are edited in the absence of any other genomically encoded mismatches. A comparison of 5'-editing in D. discoideum with 5'-editing in another slime mold, Polysphondylium pallidum, suggests organism-specific idiosyncrasies in the treatment of U-G/G-U pairs. In vitro activities of putative D. discoideum editing enzymes are consistent with the observed editing reactions and suggest an overall lack of tRNA substrate specificity exhibited by the repair component of the editing enzyme. Although the presence of terminal mismatches in mt-tRNA sequences is highly predictive of the occurrence of mt-tRNA 5'-editing, the variability in treatment of U-G/G-U base pairs observed here indicates that direct experimental evidence of 5'-editing must be obtained to understand the complete spectrum of mt-tRNA editing events in any species. PMID:24737330

Abad, Maria G; Long, Yicheng; Kinchen, R Dimitri; Schindel, Elinor T; Gray, Michael W; Jackman, Jane E

2014-05-30

51

Differential roles of ventral pallidum subregions during cocaine self-administration behaviors  

PubMed Central

The ventral pallidum (VP) is necessary for drug-seeking behavior. VP contains ventromedial (VPvm) and dorsolateral (VPdl) subregions which receive projections from the nucleus accumbens shell and core, respectively. To date, no study has investigated the behavioral functions of the VPdl and VPvm subregions. To address this issue, we investigated whether changes in firing rate (FR) differed between VP subregions during four events: approaching toward, responding on, or retreating away from a cocaine-reinforced operandum, and a cocaine-associated cue. Baseline FR and waveform characteristics did not differ between subregions. VPdl neurons exhibited a greater change in FR compared to VPvm neurons during approaches toward, as well as responses on, the cocaine-reinforced operandum. VPdl neurons were more likely to exhibit a similar change in FR (direction and magnitude) during approach and response than VPvm neurons. In contrast, VPvm firing patterns were heterogeneous, changing FRs during approach or response alone, or both. VP neurons did not discriminate cued behaviors from uncued behaviors. No differences were found between subregions during the retreat and no VP neurons exhibited patterned changes in FR in response to the cocaine-associated cue. The stronger, sustained FR changes of VPdl neurons during approach and response may implicate VPdl in the processing of drug-seeking and drug-taking behavior via projections to subthalamic nucleus and substantia nigra pars reticulata. In contrast, heterogeneous firing patterns of VPvm neurons may implicate VPvm in facilitating mesocortical structures with information related to the sequence of behaviors predicting cocaine self-infusions via projections to mediodorsal thalamus and ventral tegmental area. PMID:22806483

Root, David H.; Ma, Sisi; Barker, David J.; Megehee, Laura; Striano, Brendan M.; Ralston, Carla M.; Fabbricatore, Anthony T.; West, Mark O.

2012-01-01

52

Comparison of the locomotor-activating effects of bicuculline infusions into the preoptic area and ventral pallidum.  

PubMed

Ambulatory locomotion in the rodent is robustly activated by unilateral infusions into the basal forebrain of type A gamma-aminobutyric acid receptor antagonists, such as bicuculline and picrotoxin. The present study was carried out to better localize the neuroanatomical substrate(s) underlying this effect. To accomplish this, differences in total locomotion accumulated during a 20-min test period following bicuculline versus saline infusions in male Sprague-Dawley rats were calculated, rank ordered and mapped on a diagram of basal forebrain transposed from immunoprocessed sections. The most robust locomotor activation was elicited by bicuculline infusions clustered in rostral parts of the preoptic area. Unilateral infusions of bicuculline into the ventral pallidum produced an unanticipatedly diminutive activation of locomotion, which led us to evaluate bilateral ventral pallidal infusions, and these also produced only a small activation of locomotion, and, interestingly, a non-significant trend toward suppression of rearing. Subjects with bicuculline infused bilaterally into the ventral pallidum also exhibited persistent bouts of abnormal movements. Bicuculline infused unilaterally into other forebrain structures, including the bed nucleus of stria terminalis, caudate-putamen, globus pallidus, sublenticular extended amygdala and sublenticular substantia innominata, did not produce significant locomotor activation. Our data identify the rostral preoptic area as the main substrate for the locomotor-activating effects of basal forebrain bicuculline infusions. In contrast, slight activation of locomotion and no effect on rearing accompanied unilateral and bilateral ventral pallidal infusions. Implications of these findings for forebrain processing of reward are discussed. PMID:23423460

Zahm, Daniel S; Schwartz, Zachary M; Lavezzi, Heather N; Yetnikoff, Leora; Parsley, Kenneth P

2014-03-01

53

Reduction of Nonspecific Background Staining in the Fluorescent Treponemal Antibody-Absorption Test  

PubMed Central

The nonspecific background fluorescence which occurs with the fluorescent treponemal antibody-absorption test for syphilis was found to result from a reaction between serum-treated Treponema pallidum organisms and the conjugated antihuman ?-globulin. It was also shown that ?-lipoprotein and albumin were the important contributing factors in human serum. Various dilutions of 2.5% trypsin in phosphate-buffered saline specifically reduced background fluorescence under proper test conditions. By employing a trypsin digestion method, a semiautomated procedure utilizing a visual readout has been postulated as feasible. PMID:4177869

Roberts, Merritt E.; Miller, James N.; Binnings, Gerald F.

1968-01-01

54

Pharmacokinetic properties of arsenic species after oral administration of Sargassum pallidum extract in rats using an HPLC-HG-AFS method.  

PubMed

Sargassum pallidum is one of the Traditional Chinese Medicine widely used for phlegm elimination and detumescence. Arsenic is present in high concentration in seaweed belonging to the genus Sargassum. Therefore, the consumption of S. pallidum is a route of exposure to arsenic. Since the toxicity of arsenic is highly dependent on its chemical speciation, the determination of total arsenic is not adequate to assess the risks. Here, a high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) was developed for determination of the common arsenic species including arsenite [As(III)], dimethylarsinate (DMA), methylarsonate (MMA) and arsenate [As(V)] simultaneously. This method was applied to study the pharmacokinetic profile of these arsenic species in rats after oral administration of S. pallidum extract at different doses. The described assay was validated for limit of quantification, linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability according to the FDA validation guidelines. As(III) or MMA was not detected in any samples collected at all time points using the present HPLC-HG-AFS method. As(V) and DMA in the S. pallidum could be readily absorbed and eliminated in rats. A trend of dose-dependence was shown for DMA and As(V) in the drug concentration-time profiles. This study would be helpful for the apprehension of the action mechanism and clinical application of medicinal seaweeds. PMID:24763266

Cao, Yan; Duan, Jinao; Guo, Jianming; Li, Weixia; Tao, Weiwei

2014-08-01

55

Structure of rrn operons in pathogenic non-cultivable treponemes: sequence but not genomic position of intergenic spacers correlates with classification of Treponema pallidum and Treponema paraluiscuniculi strains  

PubMed Central

This study examined the sequences of the two rRNA (rrn) operons of pathogenic non-cultivable treponemes, comprising 11 strains of T. pallidum ssp. pallidum (TPA), five strains of T. pallidum ssp. pertenue (TPE), two strains of T. pallidum ssp. endemicum (TEN), a simian Fribourg-Blanc strain and a rabbit T. paraluiscuniculi (TPc) strain. PCR was used to determine the type of 16S–23S ribosomal intergenic spacers in the rrn operons from 30 clinical samples belonging to five different genotypes. When compared with the TPA strains, TPc Cuniculi A strain had a 17 bp deletion, and the TPE, TEN and Fribourg-Blanc isolates had a deletion of 33 bp. Other than these deletions, only 17 heterogeneous sites were found within the entire region (excluding the 16S–23S intergenic spacer region encoding tRNA-Ile or tRNA-Ala). The pattern of nucleotide changes in the rrn operons corresponded to the classification of treponemal strains, whilst two different rrn spacer patterns (Ile/Ala and Ala/Ile) appeared to be distributed randomly across species/subspecies classification, time and geographical source of the treponemal strains. It is suggested that the random distribution of tRNA genes is caused by reciprocal translocation between repetitive sequences mediated by a recBCD-like system. PMID:23082031

?ejková, Darina; Zobaníková, Marie; Pospíšilová, Petra; Strouhal, Michal; Mikalová, Lenka; Weinstock, George M.

2013-01-01

56

New Tests for Syphilis: Rational Design of a PCR Method for Detection of Treponema pallidum in Clinical Specimens Using Unique Regions of the DNA Polymerase I Gene  

Microsoft Academic Search

A sensitive and specific PCR method to detect Treponema pallidum in clinical specimens was developed. PCR primers were designed based on two unique features of the DNA polymerase I gene (polA). The first distinctive characteristic is that the region codes for a high cysteine content and has low homology with similar regions of DNA polymerase I gene from known microorganisms.

HSI LIU; BERTA RODES; C.-Y. Chen; BRET STEINER

2001-01-01

57

Whole Genome Sequence of the Treponema pallidum subsp. endemicum Strain Bosnia A: The Genome Is Related to Yaws Treponemes but Contains Few Loci Similar to Syphilis Treponemes  

PubMed Central

Background T. pallidum subsp. endemicum (TEN) is the causative agent of bejel (also known as endemic syphilis). Clinical symptoms of syphilis and bejel are overlapping and the epidemiological context is important for correct diagnosis of both diseases. In contrast to syphilis, caused by T. pallidum subsp. pallidum (TPA), TEN infections are usually spread by direct contact or contaminated utensils rather than by sexual contact. Bejel is most often seen in western Africa and in the Middle East. The strain Bosnia A was isolated in 1950 in Bosnia, southern Europe. Methodology/Principal Findings The complete genome of the Bosnia A strain was amplified and sequenced using the pooled segment genome sequencing (PSGS) method and a combination of three next-generation sequencing techniques (SOLiD, Roche 454, and Illumina). Using this approach, a total combined average genome coverage of 513× was achieved. The size of the Bosnia A genome was found to be 1,137,653 bp, i.e. 1.6–2.8 kbp shorter than any previously published genomes of uncultivable pathogenic treponemes. Conserved gene synteny was found in the Bosnia A genome compared to other sequenced syphilis and yaws treponemes. The TEN Bosnia A genome was distinct but very similar to the genome of yaws-causing T. pallidum subsp. pertenue (TPE) strains. Interestingly, the TEN Bosnia A genome was found to contain several sequences, which so far, have been uniquely identified only in syphilis treponemes. Conclusions/Significance The genome of TEN Bosnia A contains several sequences thought to be unique to TPA strains; these sequences very likely represent remnants of recombination events during the evolution of TEN treponemes. This finding emphasizes a possible role of repeated horizontal gene transfer between treponemal subspecies in shaping the Bosnia A genome. PMID:25375929

Zobaníková, Marie; ?ejková, Darina; Fulton, Lucinda L.; Chen, Lei; Giacani, Lorenzo; Centurion-Lara, Arturo; Bruisten, Sylvia M.; Sodergren, Erica; Weinstock, George M.; Šmajs, David

2014-01-01

58

The Crystal Structure of Zn(II)Free Treponema pallidum TroA, a Periplasmic Metal-Binding Protein, Reveals a Closed Conformation  

Microsoft Academic Search

We previously demonstrated that Treponema pallidum TroA is a periplasmic metal-binding protein (MBP) with a distinctive alpha-helical backbone. To better understand the mechanisms of metal binding and release by TroA, we determined the crystal structure of the apoprotein at a resolution of 2.5 Ĺ and compared it to that of the Zn(II)-bound form (Protein Data Bank accession code 1toa). apo-TroA

Yong-Hwan Lee; Michael R. Dorwart; Karsten R. O. Hazlett; Ranjit K. Deka; Michael V. Norgard; Justin D. Radolf; Charles A. Hasemann

2002-01-01

59

Syphilis-causing strains belong to separate SS14-like or Nichols-like groups as defined by multilocus analysis of 19 Treponema pallidum strains.  

PubMed

Treponema pallidum strains are closely related at the genome level but cause distinct diseases. Subspecies pallidum (TPA) is the causative agent of syphilis, subspecies pertenue (TPE) causes yaws while subspecies endemicum (TEN) causes bejel (endemic syphilis). Compared to the majority of treponemal genomic regions, several chromosomal loci were found to be more diverse. To assess genetic variability in diverse genomic positions, we have selected (based on published genomic data) and sequenced five variable loci, TP0304, TP0346, TP0488, TP0515 and TP0558, in 19 reference Treponema pallidum strains including all T. pallidum subspecies (TPA, TPE and TEN). Results of this multilocus analysis divided syphilitic isolates into two groups: SS14-like and Nichols-like. The SS14-like group is comprised of SS14, Grady, Mexico A and Philadelphia 1 strains. The Nichols-like group consisted of strains Nichols, Bal 73-1, DAL-1, MN-3, Philadelphia 2, Haiti B and Madras. The TP0558 locus was selected for further studies because it clearly distinguished between the SS14- and Nichols-like groups and because the phylogenetic tree derived from the TP0558 locus showed the same clustering pattern as the tree constructed from whole genome sequences. In addition, TP0558 was shown as the only tested locus that evolved under negative selection within TPA strains. Sequencing of a short fragment (573bp) of the TP0558 locus in a set of 25 clinical isolates from 22 patients collected in the Czech Republic during 2012-2013 revealed that clinical isolates follow the SS14- and Nichols-like distribution. PMID:24841252

Nechvátal, Lukáš; P?trošová, Helena; Grillová, Linda; Pospíšilová, Petra; Mikalová, Lenka; Strnadel, Radim; Kuklová, Ivana; Kojanová, Martina; Kreidlová, Miluše; Va?ousová, Daniela; Procházka, P?emysl; Zákoucká, Hana; Krch?áková, Alena; Smajs, David

2014-07-01

60

New Tests for Syphilis: Rational Design of a PCR Method for Detection of Treponema pallidum in Clinical Specimens Using Unique Regions of the DNA Polymerase I Gene  

PubMed Central

A sensitive and specific PCR method to detect Treponema pallidum in clinical specimens was developed. PCR primers were designed based on two unique features of the DNA polymerase I gene (polA). The first distinctive characteristic is that the region codes for a high cysteine content and has low homology with similar regions of DNA polymerase I gene from known microorganisms. The second unique feature is the presence of four insertions in the gene. PCR tests using primers designed on the basis these regions reacted with various pathogenic T. pallidum subspecies but did not react with nonpathogenic treponemal species or other spirochetes. An additional 59 species of bacteria and viruses, including those that cause genital ulcers, tested negative. This PCR method is extremely robust and sensitive. The detection limit is about 10 to 25 organisms when analyzed on gel. However, the analytic sensitivity can be increased by at least 1 log, to a detection limit of a single organism, when the ABI 310 Prism Genetic Analyzer is used to detect fluorescence-labeled amplicons. We further used this test in a clinical setting and compared the results with results from a previously reported multiplex-PCR test (for T. pallidum, Haemophilus ducreyi, and herpes simplex virus). We tested 112 genital ulcer specimens by the polA PCR, obtaining a sensitivity of 95.8% and a specificity of 95.7%. These results suggest that the polA PCR is applicable as a routine clinical diagnostic test for syphilis. PMID:11326018

Liu, Hsi; Rodes, Berta; Chen, C.-Y.; Steiner, Bret

2001-01-01

61

Use of polymerase chain reaction and rabbit infectivity testing to detect Treponema pallidum in amniotic fluid, fetal and neonatal sera, and cerebrospinal fluid.  

PubMed Central

The diagnosis of congenital syphilis continues to pose a difficult clinical challenge. Because the serodiagnosis of congenital syphilis has significant limitations, the direct detection of Treponema pallidum in suspect neonatal tissues or body fluids represents a desirable alternate diagnostic strategy. We developed and applied the polymerase chain reaction (PCR) for the detection of T. pallidum in clinical material relevant to the diagnosis of congenital syphilis but which typically contain factors inhibitory for the PCR. Four methods of specimen processing were examined to circumvent PCR inhibition; clinical materials included amniotic fluids, neonatal sera, and neonatal cerebrospinal fluids. The PCR was 100% specific for T. T. pallidum compared with the sensitive rabbit infectivity test (RIT) for all clinical materials tested. For amniotic fluids, the PCR was 100% sensitive when correlated with the RIT but had a lesser sensitivity when applied to sera or cerebrospinal fluids, which typically contain few treponemes. The combined sensitivity of the PCR for all clinical samples was 78%. Positive PCR results also were obtained among some clinical specimens for which RIT was not performed; these results correlated well with either stigmata or risk factors for congenital syphilis. The combined results suggest that the PCR can be a useful adjunct to the diagnosis and clinical management of congenital syphilis and that it will provide a valuable tool for investigations of the pathogenesis of the disorder. Images PMID:1761693

Grimprel, E; Sanchez, P J; Wendel, G D; Burstain, J M; McCracken, G H; Radolf, J D; Norgard, M V

1991-01-01

62

Antibody Dendrimers  

NASA Astrophysics Data System (ADS)

Supramolecular formations of antibodies by their specific molecular recognition to antigens are investigated. Linear and network supramolecular architectures have been constructed by using immunoglobulin G (IgG) and divalent or trivalent antigens, respectively. An amplification method of the detection signals for the target molecule in the biosensors based on the surface plasmon resonance (SPR) has been devised using the signal enhancement in the supramolecular assembly of the antibody with multivalent antigens. Novel dendritic supramolecular complexes are designed and prepared by using immunoglobulin M (IgM) or protein A/G as a core and IgGs as branches. One of the "antibody dendrimers" is composed of proteins with a molecular weight of about 2 million and constructed by non-covalent bonds. The dendrimer can bind antigens strongly with high specificity. The biosensor technique based on SPR shows that the antibody dendrimer has the advantage of amplification of detection signals for antigens.

Yamaguchi, Hiroyasu; Harada, Akira

63

Antibody dendrimers.  

PubMed

Supramolecular formations of antibodies by their specific molecular recognition to antigens are investigated. Linear and network supramolecular architectures have been constructed by using immunoglobulin G (IgG) and divalent or trivalent antigens, respectively. An amplification method of the detection signals for the target molecule in the biosensors based on the surface plasmon resonance (SPR) has been devised using the signal enhancement in the supramolecular assembly of the antibody with multivalent antigens. Novel dendritic supramolecular complexes are designed and prepared by using immunoglobulin M (IgM) or protein A/G as a core and IgGs as branches. One of the "antibody dendrimers" is composed of proteins with a molecular weight of about 2 million and constructed by non-covalent bonds. The dendrimer can bind antigens strongly with high specificity. The biosensor technique based on SPR shows that the antibody dendrimer has the advantage of amplification of detection signals for antigens. PMID:21132488

Yamaguchi, Hiroyasu; Harada, Akira

2003-01-01

64

Efficient preparation and metal specificity of the regulatory protein TroR from the human pathogen Treponema pallidum.  

PubMed

TroR is a putative metal-dependent regulatory protein that has been linked to the virulence of the human pathogen Treponema pallidum. It shares high homology with the well-known iron-dependent regulatory protein DtxR from Corynebacterium diphtheriae, as well as the manganese-dependent MntR from Bacillus subtilis. However, it has been uncertain whether manganese or zinc is the natural cofactor of TroR to date. Herein, we established an efficient method named "double-fusion tagging" to obtain soluble TroR for the first time. A series of studies, including ICP, CD, fluorescence, ITC, and electrophoresis mobility shift assay (EMSA), were performed to resolve the discrepancies in its metal-binding specificity. In addition, bioinformatic analysis as well as mutation studies were carried out to find the genetic relationships of TroR with its homology proteins. In conclusion, our findings indicate that TroR is a manganese-dependent rather than a zinc-dependent regulatory protein. PMID:23945957

Liu, Yi; Li, Wei; Wei, Yaozhu; Jiang, Yindi; Tan, Xiangshi

2013-10-01

65

Increasing Endocannabinoid Levels in the Ventral Pallidum Restores Aberrant Dopamine Neuron Activity in the Subchronic PCP Rodent Model of Schizophrenia  

PubMed Central

Schizophrenia is a debilitating disorder that affects 1% of the US population. While the exogenous administration of cannabinoids such as THC are reported to exacerbate psychosis in schizophrenia patients, augmenting the levels of endogenous cannabinoids has gained attention as a possible alternative therapy to schizophrenia due to clinical and preclinical observations. Thus, patients with schizophrenia demonstrate an inverse relationship between psychotic symptoms and levels of the endocannabinoid anandamide. In addition, increasing endocannabinoid levels (by blockade of enzymatic degradation) has been reported to attenuate social withdrawal in a preclinical model of schizophrenia. Here we examine the effects of increasing endogenous cannabinoids on dopamine neuron activity in the sub-chronic PCP model. Aberrant dopamine system function is thought to underlie the positive symptoms of schizophrenia. Using in vivo extracellular recordings in chloral hydrate anesthetized rats we now demonstrate an increase in dopamine neuron population activity in PCP-treated rats. Interestingly endocannabinoid upregulation, induced by URB-597, was able to normalize this aberrant dopamine neuron activity. Furthermore, we provide evidence that the ventral pallidum is the site where URB-597 acts to restore ventral tegmental area activity. Taken together, we provide preclinical evidence that augmenting endogenous cannabinoids may be an effective therapy for schizophrenia, acting in part to restore ventral pallidal activity. PMID:25539511

Aguilar, David D; Chen, Li; Lodge, Daniel J

2015-01-01

66

The Social Amoeba Polysphondylium pallidum Loses Encystation and Sporulation, but Can Still Erect Fruiting Bodies in the Absence of Cellulose.  

PubMed

Amoebas and other freely moving protists differentiate into walled cysts when exposed to stress. As cysts, amoeba pathogens are resistant to biocides, preventing treatment and eradication. Lack of gene modification procedures has left the mechanisms of encystation largely unexplored. Genetically tractable Dictyostelium discoideum amoebas require cellulose synthase for formation of multicellular fructifications with cellulose-rich stalk and spore cells. Amoebas of its distant relative Polysphondylium pallidum (Ppal), can additionally encyst individually in response to stress. Ppal has two cellulose synthase genes, DcsA and DcsB, which we deleted individually and in combination. Dcsa- mutants formed fruiting bodies with normal stalks, but their spore and cyst walls lacked cellulose, which obliterated stress-resistance of spores and rendered cysts entirely non-viable. A dcsa-/dcsb- mutant made no walled spores, stalk cells or cysts, although simple fruiting structures were formed with a droplet of amoeboid cells resting on an sheathed column of decaying cells. DcsB is expressed in prestalk and stalk cells, while DcsA is additionally expressed in spores and cysts. We conclude that cellulose is essential for encystation and that cellulose synthase may be a suitable target for drugs to prevent encystation and render amoeba pathogens susceptible to conventional antibiotics. PMID:25113829

Du, Qingyou; Schaap, Pauline

2014-09-01

67

Europium Nanoparticle-Based High Performing Immunoassay for the Screening of Treponemal Antibodies  

PubMed Central

Treponema pallidum subspecies pallidum (Tp) is the causative agent of syphilis which mainly spreads through sexual contact, blood transfusion and perinatal route. In order to curtail the spread of the infection and to clinically manage the disease, timely, accurate and reliable diagnosis is very important. We have developed an immunoassay for the detection of treponemal antibodies in human serum or plasma samples. In vivo biotinylated and non-biotinylated versions of the recombinant antigen were designed by the fusion of three Tp-specific antigens namely Tp15, Tp17 and Tp47. These fusion antigens were expressed in E. coli and purified using single-step metal affinity chromatography. Biotinylated fusion antigen immobilized on streptavidin coated plate was used to capture the treponemal antibodies and the non-biotinylated antigen coated on europium nanoparticles was used as tracer. Assays with two different incubation times of 10 min and 1 h were developed, and following the incubation the europium fluorescence was measured using time-resolved fluorometry. The developed time-resolved fluorometric (TRF) immunoassays were evaluated with in-house and commercial serum/plasma sample panels. For well-established treponemal antibodies positive or negative samples, the sensitivity of TRF immunoassay with 10 min incubation time was 97.4%, and of TRF immunoassay with 1 h incubation time was 98.7%, and the specificities of both the TRF immunoassays were 99.2%. For the samples with discordant results with the reference assays, both the TRF immunoassays showed better specificity than the Enzygnost syphilis enzyme immunoassay as a screening test. The two different incubation times did not have any significant effect on the signal to cutoff (S/Co) ratios obtained with the two immunoassays (p?=?0.06). Our results indicate that the developed immunoassay with a short incubation time of 10 min has the potential to be used in clinical laboratories and in blood-bank settings as a screening test for treponemal antibodies. PMID:24386329

Talha, Sheikh M.; Hytönen, Jukka; Westhorpe, Adam; Kumar, Sushil; Khanna, Navin; Pettersson, Kim

2013-01-01

68

Recently Added Antibodies  

Cancer.gov

Reagents Data Portal AntibodiesNCI 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. Print

69

Whole Genome Sequences of Three Treponema pallidum ssp. pertenue Strains: Yaws and Syphilis Treponemes Differ in Less than 0.2% of the Genome Sequence  

PubMed Central

Background The yaws treponemes, Treponema pallidum ssp. pertenue (TPE) strains, are closely related to syphilis causing strains of Treponema pallidum ssp. pallidum (TPA). Both yaws and syphilis are distinguished on the basis of epidemiological characteristics, clinical symptoms, and several genetic signatures of the corresponding causative agents. Methodology/Principal Findings To precisely define genetic differences between TPA and TPE, high-quality whole genome sequences of three TPE strains (Samoa D, CDC-2, Gauthier) were determined using next-generation sequencing techniques. TPE genome sequences were compared to four genomes of TPA strains (Nichols, DAL-1, SS14, Chicago). The genome structure was identical in all three TPE strains with similar length ranging between 1,139,330 bp and 1,139,744 bp. No major genome rearrangements were found when compared to the four TPA genomes. The whole genome nucleotide divergence (dA) between TPA and TPE subspecies was 4.7 and 4.8 times higher than the observed nucleotide diversity (?) among TPA and TPE strains, respectively, corresponding to 99.8% identity between TPA and TPE genomes. A set of 97 (9.9%) TPE genes encoded proteins containing two or more amino acid replacements or other major sequence changes. The TPE divergent genes were mostly from the group encoding potential virulence factors and genes encoding proteins with unknown function. Conclusions/Significance Hypothetical genes, with genetic differences, consistently found between TPE and TPA strains are candidates for syphilitic treponemes virulence factors. Seventeen TPE genes were predicted under positive selection, and eleven of them coded either for predicted exported proteins or membrane proteins suggesting their possible association with the cell surface. Sequence changes between TPE and TPA strains and changes specific to individual strains represent suitable targets for subspecies- and strain-specific molecular diagnostics. PMID:22292095

Chen, Lei; Pospíšilová, Petra; Strouhal, Michal; Qin, Xiang; Mikalová, Lenka; Norris, Steven J.; Muzny, Donna M.; Gibbs, Richard A.; Fulton, Lucinda L.; Sodergren, Erica; Weinstock, George M.; Šmajs, David

2012-01-01

70

Enhanced Extracellular Glutamate and Dopamine in the Ventral Pallidum of Alcohol-Preferring AA and Alcohol-Avoiding ANA Rats after Morphine  

PubMed Central

The purpose of the present study was to investigate the role of ventral pallidal opioidergic mechanisms in the control of ethanol intake by studying the effects of acute administration of morphine on the levels of GABA, glutamate, and dopamine in the ventral pallidum. The study was conducted using the alcohol-preferring Alko Alcohol (AA) and alcohol-avoiding Alko Non-Alcohol (ANA) rat lines that have well-documented differences in their voluntary ethanol intake and brain opioidergic systems. Therefore, examination of neurobiological differences between the lines is supposed to help to identify the neuronal mechanisms underlying ethanol intake, since selection pressure is assumed gradually to lead to enrichment of alleles promoting high or low ethanol intake, respectively. The effects of an acute dose of morphine (1 or 10?mg/kg s.c.) on the extracellular levels of GABA and glutamate in the ventral pallidum were monitored with in vivo microdialysis. The concentrations of GABA and glutamate in the dialyzates were determined with a high performance liquid chromatography system using fluorescent detection, while electrochemical detection was used for dopamine. The levels of glutamate in the rats injected with morphine 1?mg/kg were significantly above the levels found in the controls and in the rats receiving morphine 10?mg/kg. Morphine 10?mg/kg also increased the levels of dopamine. Morphine could not, however, modify the levels of GABA. The rat lines did not differ in any of the effects of morphine. The data suggest that the glutamatergic and dopaminergic systems in the ventral pallidum may mediate some effects of morphine. Since there were no differences between the AA and ANA lines, the basic hypothesis underlying the use of the genetic animal model suggests that the effects of morphine detected probably do not underlie the different intake of ethanol by the lines and contribute to the control of ethanol intake in these animals. PMID:25653621

Kemppainen, Heidi; Nurmi, Harri; Raivio, Noora; Kiianmaa, Kalervo

2015-01-01

71

Phenolic fractions from Trifolium pallidum and Trifolium scabrum aerial parts in human plasma protect against changes induced by hyperhomocysteinemia in vitro.  

PubMed

Elevated concentration of homocysteine (Hcy) in human plasma, defined as hyperhomocysteinemia has been correlated with some diseases, such as cardiovascular, neurodegenerative, and kidney disorders. Homocysteine occurs in human plasma in several forms, including the most reactive form of Hcy - its cyclic thioester - homocysteine thiolactone (HTL), which represents up to 0.29% of plasma total Hcy. It is suggested that Hcy and HTL may also act as oxidants, but various polyphenolic antioxidants are able to inhibit the oxidative damage induced by Hcy or HTL. The aim of our present study was to investigate in vitro oxidative changes in human plasma induced by the model of hyperhomocysteinemia in the presence of the phenolic fractions from selected clovers (Trifolium pallidum and Trifolium scabrum aerial parts). Hyperhomocysteinemia was stimulated by a reduced form of Hcy (final dose 100 ?M) or HTL (final dose 1 ?M). The aim of our study was also to explain the effect of the phenolic fractions on the coagulation activity of human plasma treated with Hcy and its thiolactone. Tested phenolic fractions significantly inhibited the oxidative stress (measured by the total antioxidant level - TAS) in plasma treated with Hcy or HTL. The phenolic fractions from T. pallidum and T. scabrum also caused a distinct reduction of plasma lipid peroxidation (measured by the level of thiobarbituric acid reactive substance) induced by the model of hyperhomocysteinemia. Moreover, tested fractions modulated the coagulation properties of plasma treated with homocysteine and its thiolactone. It seems that antioxidative activities of the phenolic fractions from T. pallidum and T. scabrum aerial parts may be responsible for their medicinal properties during hyperhomocysteinemia. PMID:22898612

Malinowska, Joanna; Ko?odziejczyk-Czepas, Joanna; Moniuszko-Szajwaj, Barbara; Kowalska, Iwona; Oleszek, Wies?aw; Stochmal, Anna; Olas, Beata

2012-11-01

72

Delta-opioid receptor blockade in the ventral pallidum increases perceived palatability and consumption of saccharin solution in rats.  

PubMed

The ventral pallidum (VP) is involved in ingestive behaviour. It receives dense GABAergic projections from the nucleus accumbens. GABAergic terminals in the VP co-express enkephalin, an endogenous ligand of delta-opioid receptors. The role of the delta-opioid receptors in the VP in the context of ingestive behaviour remains unclear, in contrast to the well-understood involvement of the mu-opioid receptors. We used the single-bottle test to examine the effects of VP microinjections of the delta-opioid receptor antagonist naltrindole on consumption of a saccharin solution. Naltrindole injections significantly increased the intake of saccharin, but not water, during a 2-h test session. We also investigated perceived palatability of saccharin using a taste reactivity test. The drug treatments increased ingestive responses to intraorally infused saccharin. Further experimentation explored the role of VP delta-opioid receptors in behavioural responses to saccharin that were previously paired with malaise upon the retrieval of conditioned taste aversion (CTA). Naltrindole-injected rats exhibited longer latency for the first occurrence of aversive responses than vehicle-injected control rats. However, there was no between-group difference in total aversive responses. These results suggest that naltrindole injections into the VP induce an enhancement of perceived palatability of a normally preferred saccharin solution, and thereby facilitate consumption of the solution. On the other hand, delayed aversive responses to the conditioned aversive saccharin suggest that the delta-opioid receptors in the VP mediate the initiation of aversive taste reactivity responses to the conditioned stimulus upon CTA retrieval. PMID:24739358

Inui, Tadashi; Shimura, Tsuyoshi

2014-08-01

73

Antiphospholipid antibodies  

Microsoft Academic Search

Conclusion  Confirmatory evidence that aPL (the LA or aCL) are associated with an increased risk for arterial and venous thrombosis, recurrent\\u000a spontaneous abortions, and fetal loss has led to increased laboratory requests for identification of these antibodies. Criteria\\u000a for the definition of the APS is now well established. At present both the pathogenesis and the optimal management of the\\u000a syndrome are

Munther A. Khamashta; Graham R. V. Hughes

1994-01-01

74

The TP0796 lipoprotein of Treponema pallidum is a bimetal-dependent FAD pyrophosphatase with a potential role in flavin homeostasis.  

PubMed

Treponema pallidum, an obligate parasite of humans and the causative agent of syphilis, has evolved the capacity to exploit host-derived metabolites for its survival. Flavin-containing compounds are essential cofactors that are required for metabolic processes in all living organisms, and riboflavin is a direct precursor of the cofactors FMN and FAD. Unlike many pathogenic bacteria, Treponema pallidum cannot synthesize riboflavin; we recently described a flavin-uptake mechanism composed of an ABC-type transporter. However, there is a paucity of information about flavin utilization in bacterial periplasms. Using a discovery-driven approach, we have identified the TP0796 lipoprotein as a previously uncharacterized Mg(2+)-dependent FAD pyrophosphatase within the ApbE superfamily. TP0796 probably plays a central role in flavin turnover by hydrolyzing exogenously acquired FAD, yielding AMP and FMN. Biochemical and structural investigations revealed that the enzyme has a unique bimetal Mg(2+) catalytic center. Furthermore, the pyrophosphatase activity is product-inhibited by AMP, indicating a possible role for this molecule in modulating FMN and FAD levels in the treponemal periplasm. The ApbE superfamily was previously thought to be involved in thiamine biosynthesis, but our characterization of TP0796 prompts a renaming of this superfamily as a periplasmic flavin-trafficking protein (Ftp). TP0796 is the first structurally and biochemically characterized FAD pyrophosphate enzyme in bacteria. This new paradigm for a bacterial flavin utilization pathway may prove to be useful for future inhibitor design. PMID:23447540

Deka, Ranjit K; Brautigam, Chad A; Liu, Wei Z; Tomchick, Diana R; Norgard, Michael V

2013-04-19

75

The TP0796 Lipoprotein of Treponema pallidum Is a Bimetal-dependent FAD Pyrophosphatase with a Potential Role in Flavin Homeostasis*  

PubMed Central

Treponema pallidum, an obligate parasite of humans and the causative agent of syphilis, has evolved the capacity to exploit host-derived metabolites for its survival. Flavin-containing compounds are essential cofactors that are required for metabolic processes in all living organisms, and riboflavin is a direct precursor of the cofactors FMN and FAD. Unlike many pathogenic bacteria, Treponema pallidum cannot synthesize riboflavin; we recently described a flavin-uptake mechanism composed of an ABC-type transporter. However, there is a paucity of information about flavin utilization in bacterial periplasms. Using a discovery-driven approach, we have identified the TP0796 lipoprotein as a previously uncharacterized Mg2+-dependent FAD pyrophosphatase within the ApbE superfamily. TP0796 probably plays a central role in flavin turnover by hydrolyzing exogenously acquired FAD, yielding AMP and FMN. Biochemical and structural investigations revealed that the enzyme has a unique bimetal Mg2+ catalytic center. Furthermore, the pyrophosphatase activity is product-inhibited by AMP, indicating a possible role for this molecule in modulating FMN and FAD levels in the treponemal periplasm. The ApbE superfamily was previously thought to be involved in thiamine biosynthesis, but our characterization of TP0796 prompts a renaming of this superfamily as a periplasmic flavin-trafficking protein (Ftp). TP0796 is the first structurally and biochemically characterized FAD pyrophosphate enzyme in bacteria. This new paradigm for a bacterial flavin utilization pathway may prove to be useful for future inhibitor design. PMID:23447540

Deka, Ranjit K.; Brautigam, Chad A.; Liu, Wei Z.; Tomchick, Diana R.; Norgard, Michael V.

2013-01-01

76

Reagents Data Portal Antibodies  

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.

77

Proposal of a new halobacterial genus Natrinema gen. nov., with two species Natrinema pellirubrum nom. nov. and Natrinema pallidum nom. nov.  

PubMed

A phylogenetic analysis of 69 halobacterial 16S rRNA gene sequences has been carried out, integrating data from new isolates, previously described halobacteria and cloned sequences from uncultivated halobacteria. Halobacterium halobium NCIMB 777, Halobacterium trapanicum NCIMB 784 and Halobacterium salinarium NCIMB 786, together with several other strains (strains T5.7, L11 and Halobacterium trapanicum NCIMB 767) constitute a distinct lineage with at least 98.2% sequence similarity. These strains have been incorrectly assigned to the genus Halobacterium. Therefore, based on a variety of taxonomic criteria, it is proposed that Halobacterium salinarium NCIMB 786 is renamed as Natrinema pellirubrum nom. nov., the type species of the new genus Natrinema gen. nov., and that Halobacterium halobium NCIMB 777 and Halobacterium trapanicum NCIMB 784 are renamed as a single species, Natrinema pallidum nom. nov. It was notable that halobacteria closely related to the proposed new genus have been isolated from relatively low-salt environments. PMID:9828420

McGenity, T J; Gemmell, R T; Grant, W D

1998-10-01

78

Antipsychotic drug-induced increases in ventral tegmental area dopamine neuron population activity via activation of the nucleus accumbens-ventral pallidum pathway.  

PubMed

Acute administration of antipsychotic drugs increases dopamine (DA) neuron activity and DA release via D2 receptor blockade. However, it is unclear whether the DA neuron activation produced by antipsychotic drugs is due to feedback from post-synaptic blockade or is due to an action on DA neuron autoreceptors. This was evaluated using two drugs: the first-generation antipsychotic drug haloperidol that has potent D2 blocking properties, and the second-generation drug sertindole, which is unique in that it is reported to fail to reverse the apomorphine-induced decrease in firing rate typically associated with DA neuron autoreceptor stimulation. Using single-unit extracellular recordings from ventral tegmental area (VTA) DA neurons in anaesthetized rats, both drugs were found to significantly increase the number of spontaneously active DA neurons (population activity). Apomorphine administered within 10 min either before or after sertindole reversed the sertindole-induced increase in population activity, but had no effect when administered 1 h after sertindole. Moreover, both sertindole- and haloperidol-induced increase in population activity was prevented when nucleus accumbens feedback was interrupted by local infusion of the GABAA antagonist bicuculline into the ventral pallidum. Taken together, these data suggest that antipsychotics increase DA neuron population activity via a common action on the nucleus accumbens-ventral pallidum-VTA feedback pathway and thus provide further elucidation on the mechanism by which antipsychotic drugs affect DA neuron activity. This provides an important insight into the relationship between altered DA neuron activity and potential antipsychotic efficacy. PMID:19751544

Valenti, Ornella; Grace, Anthony A

2010-08-01

79

Serum antibodies to whole-cell and recombinant antigens of Borrelia burgdorferi in cottontail rabbits.  

PubMed

Archived serum samples, from 95 eastern cottontail rabbits (Sylvilagus floridanus) captured in New York, New York, USA and Millbrook, New York, USA, during 1985-86, were analyzed in solid-phase enzyme-linked immunosorbent assays (ELISA) for total and class-specific immunoglobulin (Ig) M antibodies to whole-cell or recombinant antigens of Borrelia burgdorferi sensu stricto. Using a polyvalent conjugate, rabbit sera contained antibodies to whole-cell and recombinant antigens (protein [p]35, p37, or VlsE) during different seasons, but there was no reactivity to outer surface protein (Osp)A or OspB. Seventy-six of the 102 sera (75%) analyzed were reactive with one or more of the antigens; 61 of the positive samples (80%) reacted to whole-cell antigens, followed by results for the p35 (58%, 44/76), VlsE (43%, 33/76), and p37 (29%, 22/ 76) antigens. Fifty-eight sera (76%) contained antibodies to the VlsE or p35 antigens with or without reactivity to whole-cell antigens. High antibody titers (?1:2,560) recorded for 52 sera indicate robust antibody production. In analyses for IgM antibodies in an ELISA containing whole-cell antigens, there were 30 positive sera; titers ranged from 1:160 to 1:640. There was minimal cross-reactivity when rabbit antisera to Treponema pallidum or four serovars of Leptospira interrogans were screened against B. burgdorferi antigens. Based on more-specific results, VlsE and p35 antigens appear to be useful markers for detecting possible B. burgdorferi infections. PMID:22247369

Magnarelli, Louis A; Norris, Steven J; Fikrig, Erol

2012-01-01

80

SERUM ANTIBODIES TO WHOLE-CELL AND RECOMBINANT ANTIGENS OF BORRELIA BURGDORFERI IN COTTONTAIL RABBITS  

PubMed Central

Archived serum samples, from 95 eastern cottontail rabbits (Sylvilagus floridanus) captured in New York, New York, USA and Millbrook, New York, USA, during 1985–86, were analyzed in solid-phase enzyme-linked immunosorbent assays (ELISA) for total and class-specific immunoglobulin (Ig) M antibodies to whole-cell or recombinant antigens of Borrelia burgdorferi sensu stricto. Using a polyvalent conjugate, rabbit sera contained antibodies to whole-cell and recombinant antigens (protein [p]35, p37, or VlsE) during different seasons, but there was no reactivity to outer surface protein (Osp)A or OspB. Seventy-six of the 102 sera (75%) analyzed were reactive with one or more of the antigens; 61 of the positive samples (80%) reacted to whole-cell antigens, followed by results for the p35 (58%, 44/76), VlsE (43%, 33/76), and p37 (29%, 22/76) antigens. Fifty-eight sera (76%) contained antibodies to the VlsE or p35 antigens with or without reactivity to whole-cell antigens. High antibody titers (?1:2,560) recorded for 52 sera indicate robust antibody production. In analyses for IgM antibodies in an ELISA containing whole-cell antigens, there were 30 positive sera; titers ranged from 1:160 to 1:640. There was minimal cross-reactivity when rabbit antisera to Treponema pallidum or four serovars of Leptospira interrogans were screened against B. burgdorferi antigens. Based on more-specific results, VlsE and p35 antigens appear to be useful markers for detecting possible B. burgdorferi infections. PMID:22247369

Magnarelli, Louis A.; Norris, Steven J.; Fikrig, Erol

2011-01-01

81

Platelet associated antibodies  

MedlinePLUS

... need this test when you have a low platelet count (thrombocytopenia). It is used to detect antibodies against ... platelets and destroy them. This causes a low platelet count, which can lead to excessive bleeding. Antiplatelet antibodies ...

82

GE Healthcare Antibody Purification  

E-print Network

GE Healthcare Antibody Purification Handbook GE Healthcare imagination at work agination at work from GE Healthcare #12;Antibody Purification Handbook #12; Handbook 18-1037-46 AD Contents Introduction

Lebendiker, Mario

83

Antibodies, viruses and vaccines  

Microsoft Academic Search

Neutralizing antibodies are crucial for vaccine-mediated protection against viral diseases. They probably act, in most cases, by blunting the infection, which is then resolved by cellular immunity. The protective effects of neutralizing antibodies can be achieved not only by neutralization of free virus particles, but also by several activities directed against infected cells. In certain instances, non-neutralizing antibodies contribute to

Dennis R. Burton

2002-01-01

84

[VGKC-complex antibodies].  

PubMed

Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease). PMID:23568988

Watanabe, Osamu

2013-04-01

85

Effects of electrical lesions of the medial preoptic area and the ventral pallidum on mate-dependent paternal behavior in mice.  

PubMed

In laboratory animals, less is known about the neural circuits that mediate paternal behavior than those that influence maternal behavior. In mice, we recently reported that when sires are separated with their mate dams from their pups, ultrasound and pheromonal signals from the dams can evoke and initiate maternal-like retrieval behavior in the sires upon reunion with the offspring; this is termed mate-dependent paternal care. We used electrolytic brain lesion (EBL) methods to identify the potential roles of the medial preoptic area (mPOA) and ventral pallidum (VP) regions in regulating paternal care, areas known to be critical for the expression of maternal behavior. Electrolytic lesions of the mPOA or VP disrupted mate-dependent paternal care; latencies to initiate pup retrieval, grooming and crouching were longer in the EBL-treated sires relative to the sham-operated mice. The number of grooming episodes and duration of crouching were also lower in sires with the EBL in both areas. These results indicate that the mPOA and VP regions are essential for mate-dependent paternal care in mice. PMID:24721669

Akther, Shirin; Fakhrul, Azam A K M; Higashida, Haruhiro

2014-06-01

86

Structural and thermodynamic characterization of the interaction between two periplasmic Treponema pallidum lipoproteins that are components of a TPR-protein-associated TRAP transporter (TPAT)  

PubMed Central

Tripartite ATP-independent periplasmic transporters (TRAP-Ts) are bacterial transport systems that have been implicated in the import of small molecules into the cytoplasm. A newly discovered subfamily of TRAP-Ts (TPATs) has four components. Three are common to both TRAP-Ts and TPATs: the P component, a ligand-binding protein, and a transmembrane symporter apparatus comprising the M and Q components (M and Q are sometimes fused to form a single polypeptide). TPATs are distinguished from TRAP-Ts by the presence of a unique protein called the “T component”. In Treponema pallidum, this protein (TatT) is a water-soluble trimer whose protomers are each perforated by a pore. Its respective P component (TatPT) interacts with the TatT in vitro and in vivo. In this work, we further characterized this interaction. Co-crystal structures of two complexes between the two proteins confirm that up to three monomers of TatPT can bind to the TatT trimer. A putative ligand-binding cleft of TatPT aligns with the pore of TatT, strongly suggesting ligand transfer between T and PT. We used a combination of site-directed mutagenesis and analytical ultracentrifugation to derive thermodynamic parameters for the interactions. These observations confirm that the observed crystallographic interface is recapitulated in solution. These results prompt a hypothesis of the molecular mechanism(s) of hydrophobic ligand transport by the TPATs. PMID:22504226

Brautigam, Chad A.; Deka, Ranjit K.; Schuck, Peter; Tomchick, Diana R.; Norgard, Michael V.

2012-01-01

87

Insights into the potential function and membrane organization of the TP0435 (Tp17) lipoprotein from Treponema pallidum derived from structural and biophysical analyses.  

PubMed

The sexually transmitted disease syphilis is caused by the bacterial spirochete Treponema pallidum. This microorganism is genetically intractable, accounting for the large number of putative and undercharacterized members of the pathogen's proteome. In an effort to ascribe a function(s) to the TP0435 (Tp17) lipoprotein, we engineered a soluble variant of the protein (rTP0435) and determined its crystal structure at a resolution of 2.42 Ĺ. The structure is characterized by an eight-stranded ?-barrel protein with a shallow "basin" at one end of the barrel and an ?-helix stacked on the opposite end. Furthermore, there is a disulfide-linked dimer of the protein in the asymmetric unit of the crystals. Solution hydrodynamic experiments established that purified rTP0435 is monomeric, but specifically forms the disulfide-stabilized dimer observed in the crystal structure. The data herein, when considered with previous work on TP0435, imply plausible roles for the protein in either ligand binding, treponemal membrane architecture, and/or pathogenesis. PMID:25287511

Brautigam, Chad A; Deka, Ranjit K; Liu, Wei Z; Norgard, Michael V

2015-01-01

88

Biobarcodes: Antibodies and Nanosensors  

NSDL National Science Digital Library

In this activity/demo, learners investigate biobarcodes, a nanomedical technology that allows for massively parallel testing that can assist with disease diagnosis. Learners define antibodies and learn how each antibody binds to a unique protein. Learners also discover how biobarcoding uses nanoparticles, antibodies, DNA and magnetism to detect diseases earlier than we could detect before. Learners assemble a jigsaw puzzle that models how biobarcodes work.

Nanoscale Informal Science Education Network

2014-06-04

89

RSV antibody test  

MedlinePLUS

Respiratory syncytial virus antibody test; RSV serology ... Breese HC. Respiratory syncytial virus. In: Mandell GL, Bennett JE, Dolin R, eds. Mandel, Douglas, and Bennett's Principles and Practice of ...

90

Natural Antibodies Against Sialoglycans.  

PubMed

Natural antibodies, part of the innate immunity system, are produced at strictly regulated levels in normal sera without immunization and thus are part of the innate immune system. The best studied natural antibodies are those directed against blood group antigens A and B and xeno-antigens including glycolylneuraminic acid containing Hanganutziu-Deicher (HD) glycolipid. Abnormal levels of anti-glycan antibodies were found in a number of pathologies. In many cases pathological antibodies are known to bind gangliosides. The genesis of anti-glycan antibodies in healthy humans and the reasons for their changes in pathologies are poorly understood. With a growing interest in their diagnostic applications, it is important to determine the carbohydrate structures that are recognized by antibodies present in the circulation of healthy individuals. We tested a large number of healthy donors using a printed glycan array (PGA) in a microchip format. The PGA contained ~300 glycans, representing mostly normal mammalian structures of glycoproteins and glycolipids, and many of the structures presented are biologically relevant sialylated motifs. As revealed by PGA, the sera interacted with at least 70 normal human glycans. With only few exceptions, antibodies recognizing sialosides have not been identified. Moderate levels of antibodies and moderate variability were observed in the case of SiaT n and its glycolyl variant. Unexpectedly, we found minimal antibody titer directed against Neu5Gc? and the trisaccharide Neu5Gc?2-6Gal?1-4GlcNAc, although this form of neuraminic acid does not occur naturally in humans. Antibodies recognizing sialosides in unnatural ?-configuration have been detected and confirmed Springer's paradigm that circulating antibodies represent a reaction against bacteria. Gram-negative bacteria contain LPS with ?KDN and/or ?KDO which are very close analogs of Neu5Ac that are found in ?-connected form. Antibodies against the biantennary N-glycan chain, (Neu5Ac?2-6Gal?1-4GlcNAc?1-2Man?)2-3,6-Man?1-4GlcNAc?1-4GlcNAc were never observed and similarly we never saw antibodies directed against the SiaLe(a)/SiaLe (x) motifs. Anti-sialoglycan antibodies can be masked with gangliosides: for example, we observe about a five times higher level of anti-GD3 in purified total IgG compared to the same concentration of total Ig in the composition of native serum. For several antibodies we observed anomalous binding in diluted sera, namely, the signals towards sialylated glycans were increased in the PGA if diluted sera were used. PMID:24037491

Shilova, Nadezhda; Huflejt, Margaret E; Vuskovic, Marko; Obukhova, Polina; Navakouski, Maksim; Khasbiullina, Nailya; Pazynina, Galina; Galanina, Oxana; Bazhenov, Alexey; Bovin, Nicolai

2013-09-14

91

Changes in Accumbal and Pallidal pCREB and ?FosB in Morphine-Sensitized Rats: Correlations with Receptor-Evoked Electrophysiological Measures in the Ventral Pallidum  

PubMed Central

Activation of ?-opioid receptors in the ventral pallidum (VP) is important for the induction of behavioral sensitization to morphine in rats. The present study was designed to ascertain if neurons within the VP demonstrate sensitization at a time when morphine-induced behavioral sensitization occurred (ie 3 or 14 days after five once-daily injections of 10 mg/kg i.p. morphine) in rats. Western blotting was used to evaluate transcription factors altered by opiates, CREB and ?FosB. CREB levels did not change in the VP, but there was a significant decrease in levels of its active, phosphorylated form (pCREB) at both 3- and 14-days withdrawal. ?FosB levels were elevated following a 3-day withdrawal, but returned to normal by 14 days. This profile also was obtained from nucleus accumbens tissue. In a separate group of similarly treated rats, in vivo electrophysiological recordings of VP neuronal responses to microiontophoretically applied ligands were carried out after 14-days withdrawal. The firing rate effects of local applications of morphine were diminished in rats withdrawn from i.p. morphine. Repeated i.p. morphine did not alter GABA-mediated suppression of firing, or the rate enhancing effects of the D1 dopamine receptor agonist SKF82958 or glutamate. However, VP neurons from rats withdrawn from repeated i.p. morphine showed a higher propensity to enter a state of depolarization inactivation to locally applied glutamate. Overall, these findings reveal that decreased pCREB in brain regions such as the VP accompanies persistent behavioral sensitization to morphine and that this biochemical alteration may influence the excitability of neurons in this brain region. PMID:16123760

McDaid, John; Dallimore, Jeanine E; Mackie, Alexander R; Napier, T Celeste

2005-01-01

92

Expression of Recombinant Antibodies  

PubMed Central

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

Frenzel, André; Hust, Michael; Schirrmann, Thomas

2013-01-01

93

Therapeutic Recombinant Monoclonal Antibodies  

ERIC Educational Resources Information Center

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…

Bakhtiar, Ray

2012-01-01

94

The antiphospholipid antibody syndrome  

Microsoft Academic Search

The antiphospholipid antibody syndrome (APS) is the association of certain clinical features with the presence of antiphospholipid antibodies (APA) in the serum or plasma of affected individuals. APS may be primary or secondary to another disease, typically autoimmune diseases such as systemic lupus erythematosus (SLE).The prototypic clinical features are thrombotic events (venous and arterial) and pregnancy morbidity (recurrent fetal loss,

Michael C Nimmo; Cedric J Carter

2003-01-01

95

Production Of Human Antibodies  

NASA Technical Reports Server (NTRS)

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.

Sammons, David W.; Neil, Garry A.

1993-01-01

96

Induction of antiphosphorylcholine antibody formation by anti-idiotypic antibodies.  

PubMed

Anti-idiotypic antibodies have been used to mimic antigen in the mouse antiphosphorylcholine response in order to investigate the induction of precursors of antibody-forming cells. We have shown that interaction of anti-idiotype antibody with receptor antibody molecules induces the formation of antibodies that are specific for phosphorylcholine and carry the idiotypic determinants. This induction is dependent on the recognition of carrier determinants on the anti-idiotype antibody by helper T cells. We conclude that receptor antibody molecules on the surface of the precursors of antibody-forming cells deliver the antigenic signal for the induction of these cells. PMID:53257

Trenkner, E; Riblet, R

1975-11-01

97

Red Blood Cell Antibody Identification  

MedlinePLUS

... Antibody ID, RBC; RBC Ab ID Formal name: Red Blood Cell Antibody Identification Related tests: Direct Antiglobulin ... None The Test Sample What is being tested? Red blood cell antibodies are proteins produced by the ...

98

Antibodies for biodefense  

PubMed Central

Potential bioweapons are biological agents (bacteria, viruses and toxins) at risk of intentional dissemination. Biodefense, defined as development of therapeutics and vaccines against these agents, has seen an increase, particularly in the US, following the 2001 anthrax attack. This review focuses on recombinant antibodies and polyclonal antibodies for biodefense that have been accepted for clinical use. These antibodies aim to protect against primary potential bioweapons or category A agents as defined by the Centers for Disease Control and Prevention (Bacillus anthracis, Yersinia pestis, Francisella tularensis, botulinum neurotoxins, smallpox virus and certain others causing viral hemorrhagic fevers) and certain category B agents. Potential for prophylactic use is presented, as well as frequent use of oligoclonal antibodies or synergistic effect with other molecules. Capacities and limitations of antibodies for use in biodefense are discussed, and are generally applicable to the field of infectious diseases. PMID:22123065

Froude, Jeffrey W; Stiles, Bradley; Pelat, Thibaut

2011-01-01

99

Sputum direct fluorescent antibody (DFA)  

MedlinePLUS

Direct immunofluorescence test; Direct fluorescent antibody - sputum ... fluorescent dye are added to the sample. These antibodies are ... bright glow (fluorescence) can be seen in the sputum sample using ...

100

Blue-Fluorescent Antibodies  

NASA Astrophysics Data System (ADS)

The forte of catalytic antibodies has resided in the control of the ground-state reaction coordinate. A principle and method are now described in which antibodies can direct the outcome of photophysical and photochemical events that take place on excited-state potential energy surfaces. The key component is a chemically reactive optical sensor that provides a direct report of the dynamic interplay between protein and ligand at the active site. To illustrate the concept, we used a trans-stilbene hapten to elicit a panel of monoclonal antibodies that displayed a range of fluorescent spectral behavior when bound to a trans-stilbene substrate. Several antibodies yielded a blue fluorescence indicative of an excited-state complex or ``exciplex'' between trans-stilbene and the antibody. The antibodies controlled the isomerization coordinate of trans-stilbene and dynamically coupled this manifold with an active-site residue. A step was taken toward the use of antibody-based photochemical sensors for diagnostic and clinical applications.

Simeonov, Anton; Matsushita, Masayuki; Juban, Eric A.; Thompson, Elizabeth H. Z.; Hoffman, Timothy Z.; Beuscher, Albert E.; Taylor, Matthew J.; Wirsching, Peter; Rettig, Wolfgang; McCusker, James K.; Stevens, Raymond C.; Millar, David P.; Schultz, Peter G.; Lerner, Richard A.; Janda, Kim D.

2000-10-01

101

nkx2.1 and nkx2.4 genes function partially redundant during development of the zebrafish hypothalamus, preoptic region, and pallidum.  

PubMed

During ventral forebrain development, orthologs of the homeodomain transcription factor Nkx2.1 control patterning of hypothalamus, preoptic region, and ventral telencephalon. However, the relative contributions of Nkx2.1 and Nkx2.4 to prosencephalon development are poorly understood. Therefore, we analyzed functions of the previously uncharacterized nkx2.4-like zgc:171531 as well as of the presumed nkx2.1 orthologs nkx2.1a and nkx2.1b in zebrafish forebrain development. Our results show that zgc:171531 and nkx2.1a display overlapping expression patterns and a high sequence similarity. Together with a high degree of synteny conservation, these findings indicate that both these genes indeed are paralogs of nkx2.4. As a result, we name zgc:171531 now nkx2.4a, and changed the name of nkx2.1a to nkx2.4b, and of nkx2.1b to nkx2.1. In nkx2.1, nkx2.4a, and nkx2.4b triple morpholino knockdown (nkx2TKD) embryos we observed a loss of the rostral part of prosomere 3 and its derivative posterior tubercular and hypothalamic structures. Furthermore, there was a loss of rostral and intermediate hypothalamus, while a residual preoptic region still develops. The reduction of the ventral diencephalon was accompanied by a ventral expansion of the dorsally expressed pax6, revealing a dorsalization of the basal hypothalamus. Within the telencephalon we observed a loss of pallidal markers, while striatum and pallium are forming. At the neuronal level, nkx2TKD morphants lacked several neurosecretory neuron types, including avp, crh, and pomc expressing cells in the hypothalamus, but still form oxt neurons in the preoptic region. Our data reveals that, while nkx2.1, nkx2.4a, and nkx2.4b genes act partially redundant in hypothalamic development, nkx2.1 is specifically involved in the development of rostral ventral forebrain including the pallidum and preoptic regions, whereas nkx2.4a and nkx2.4b control the intermediate and caudal hypothalamus. PMID:25520628

Manoli, Martha; Driever, Wolfgang

2014-01-01

102

nkx2.1 and nkx2.4 genes function partially redundant during development of the zebrafish hypothalamus, preoptic region, and pallidum  

PubMed Central

During ventral forebrain development, orthologs of the homeodomain transcription factor Nkx2.1 control patterning of hypothalamus, preoptic region, and ventral telencephalon. However, the relative contributions of Nkx2.1 and Nkx2.4 to prosencephalon development are poorly understood. Therefore, we analyzed functions of the previously uncharacterized nkx2.4-like zgc:171531 as well as of the presumed nkx2.1 orthologs nkx2.1a and nkx2.1b in zebrafish forebrain development. Our results show that zgc:171531 and nkx2.1a display overlapping expression patterns and a high sequence similarity. Together with a high degree of synteny conservation, these findings indicate that both these genes indeed are paralogs of nkx2.4. As a result, we name zgc:171531 now nkx2.4a, and changed the name of nkx2.1a to nkx2.4b, and of nkx2.1b to nkx2.1. In nkx2.1, nkx2.4a, and nkx2.4b triple morpholino knockdown (nkx2TKD) embryos we observed a loss of the rostral part of prosomere 3 and its derivative posterior tubercular and hypothalamic structures. Furthermore, there was a loss of rostral and intermediate hypothalamus, while a residual preoptic region still develops. The reduction of the ventral diencephalon was accompanied by a ventral expansion of the dorsally expressed pax6, revealing a dorsalization of the basal hypothalamus. Within the telencephalon we observed a loss of pallidal markers, while striatum and pallium are forming. At the neuronal level, nkx2TKD morphants lacked several neurosecretory neuron types, including avp, crh, and pomc expressing cells in the hypothalamus, but still form oxt neurons in the preoptic region. Our data reveals that, while nkx2.1, nkx2.4a, and nkx2.4b genes act partially redundant in hypothalamic development, nkx2.1 is specifically involved in the development of rostral ventral forebrain including the pallidum and preoptic regions, whereas nkx2.4a and nkx2.4b control the intermediate and caudal hypothalamus. PMID:25520628

Manoli, Martha; Driever, Wolfgang

2014-01-01

103

Bispecific Single Domain Antibodies  

Microsoft Academic Search

\\u000a Monoclonal antibodies are now widely recognized as therapeutic molecules and more than 25 molecules have been approved in\\u000a the United States and other countries. Despite these successes, the clinical activity of these molecules is still far from\\u000a optimal and new solutions have to be found, especially in the field of cancer therapy. The potential of bispecific antibodies,\\u000a capable of simultaneously

Patrick Chames; Daniel Baty

104

Antibody tumor penetration  

PubMed Central

Antibodies have proven to be effective agents in cancer imaging and therapy. One of the major challenges still facing the field is the heterogeneous distribution of these agents in tumors when administered systemically. Large regions of untargeted cells can therefore escape therapy and potentially select for more resistant cells. We present here a summary of theoretical and experimental approaches to analyze and improve antibody penetration in tumor tissue. PMID:18541331

Thurber, Greg M.; Schmidt, Michael M.; Wittrup, K. Dane

2009-01-01

105

Antibody informatics for drug discovery.  

PubMed

More and more antibody therapeutics are being approved every year, mainly due to their high efficacy and antigen selectivity. However, it is still difficult to identify the antigen, and thereby the function, of an antibody if no other information is available. There are obstacles inherent to the antibody science in every project in antibody drug discovery. Recent experimental technologies allow for the rapid generation of large-scale data on antibody sequences, affinity, potency, structures, and biological functions; this should accelerate drug discovery research. Therefore, a robust bioinformatic infrastructure for these large data sets has become necessary. In this article, we first identify and discuss the typical obstacles faced during the antibody drug discovery process. We then summarize the current status of three sub-fields of antibody informatics as follows: (i) recent progress in technologies for antibody rational design using computational approaches to affinity and stability improvement, as well as ab-initio and homology-based antibody modeling; (ii) resources for antibody sequences, structures, and immune epitopes and open drug discovery resources for development of antibody drugs; and (iii) antibody numbering and IMGT. Here, we review "antibody informatics," which may integrate the above three fields so that bridging the gaps between industrial needs and academic solutions can be accelerated. This article is part of a Special Issue entitled: Recent advances in molecular engineering of antibody. PMID:25110827

Shirai, Hiroki; Prades, Catherine; Vita, Randi; Marcatili, Paolo; Popovic, Bojana; Xu, Jianqing; Overington, John P; Hirayama, Kazunori; Soga, Shinji; Tsunoyama, Kazuhisa; Clark, Dominic; Lefranc, Marie-Paule; Ikeda, Kazuyoshi

2014-11-01

106

Glycoproteomic Analysis of Antibodies*  

PubMed Central

Antibody glycosylation has been shown to change with various processes. This review presents mass spectrometric approaches for antibody glycosylation analysis at the level of released glycans, glycopeptides, and intact protein. With regard to IgG fragment crystallizable glycosylation, mass spectrometry has shown its potential for subclass-specific, high-throughput analysis. In contrast, because of the vast heterogeneity of peptide moieties, fragment antigen binding glycosylation analysis of polyclonal IgG relies entirely on glycan release. Next to IgG, IgA has gained some attention, and studies of its O- and N-glycosylation have revealed disease-associated glycosylation changes. Glycoproteomic analyses of IgM and IgE are lagging behind but should complete our picture of glycosylation's influence on antibody function. PMID:23325769

Zauner, Gerhild; Selman, Maurice H. J.; Bondt, Albert; Rombouts, Yoann; Blank, Dennis; Deelder, André M.; Wuhrer, Manfred

2013-01-01

107

An Antibody Molecule  

NSDL National Science Digital Library

An antibody molecule. (A) Schematic drawing of a typical antibody molecule. As indicated, this protein is Y-shaped and has two identical binding sites for its antigen, one on either arm of the 3Y.2 The protein is composed of four polypeptide chains (two identical heavy chains and two identical and smaller light chains) held together by disulfide bonds. Each chain is made up of several different domains, here shaded either blue or gray. The antigen-binding site is formed where a heavy chain variable domain (VH) and a light chain variable domain (VL) come close together. These are the domains that differ most in their sequence and structure in different antibodies. (B) Ribbon drawing of a light chain showing the parts of the VL domain most closely involved in binding to the antigen in red; these contribute half of the fingerlike loops that fold around each of the antigen molecules in (A).

Martin Raff

1998-07-01

108

Antibody therapeutics, antibody engineering, and the merits of protein stability.  

PubMed

Antibodies are highly soluble, multidomain proteins that are well suited for biopharmaceutical development; however, engineering antibodies to perform novel activities or to have enhanced clinical utility can have a detrimental effect on their biophysical properties. Various innovative designs, such as single-chain variable fragments (scFvs) and domain antibodies (dAbs), have been utilized to obtain the antigen-binding properties of natural antibodies, while using a minimal amount of the polypeptide sequence of an antibody. These designs can be used for generating diverse antibody libraries to support discovery and optimization and also serve as excellent building blocks for constructing more complex protein therapeutics, such as bispecific antibodies. However, engineered antibody-like proteins, including scFvs, are often unstable and prone to aggregation, compromising both protein production and quality. Research over the past few years has enhanced our understanding of how interdomain interactions within antibodies contribute to protein stability. This knowledge and sustained research to develop methods for modifying antibody fragments to improve stability have begun to have a positive impact on the quality of antibody libraries for discovery purposes and the viability of highly engineered proteins, such as bispecific antibodies, as therapeutics. PMID:18729019

Demarest, Stephen J; Glaser, Scott M

2008-09-01

109

Humanized Antibodies for Antiviral Therapy  

NASA Astrophysics Data System (ADS)

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.

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

1991-04-01

110

ANTIBODY PRODUCTION IN VITRO  

PubMed Central

The effects of actinomycin D and puromycin on spleen cell suspensions from rabbits immunized to SRC's were studied. These inhibitors, in high concentration, suppressed PFC's when added initially to recently isolated cells. When such cells were incubated for several days in the presence of both antigen and inhibitor, both actinomycin D and puromycin produced an increase in PFC's after the initial suppression. This recovery effect was best seen with cells from rabbits killed 3 days after boosting with SRC's, and was usually absent when cells were taken from rabbits killed 2 days after boosting. When actinomycin D or puromycin was added after several days in culture in the presence of SRC's, surviving PFC's were found to be not only resistant to these inhibitors, but there was also an increased number of PFC's compared to similar cultures incubated without these agents. Radioautographic studies showed that PFC's stimulated by the presence of actinomycin D or puromycin were not incorporating precursors for RNA or protein synthesis. In view of the known mode of action of these inhibitors, it was postulated that they were stimulating antibody production by PFC's in vitro either by interfering with represser mechanisms or stimulating the completion of antibody molecules, perhaps by causing the release of preformed antibody chains from ribosomes. Since the presence of specific antigens in vitro were necessary for these observed stimulatory effects on PFC's, and since antigens were producing an effect on antibody production on cells which were being suppressed by these inhibitors, added initially, it was further suggested that one role of antigen in the immune response was concerned with the completion of antibody synthesis on the ribosomes, perhaps by acting as an inducer as has been suggested previously (1). PMID:5642464

Harris, Gilmour

1968-01-01

111

Antibody-gold cluster conjugates  

DOEpatents

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.

Hainfeld, J.F.

1988-06-28

112

Her2 Monoclonal Antibodies, Antibody Drug Conjugates, and Site Specific Antibody Conjugate Methods  

Cancer.gov

Antibody drug conjugates (ADC) can demonstrate high efficacy as cancer therapeutics, however, much more can be done to improve their efficacy and safety profile. Site-specific antibody drug conjugation is a promising way to do this.

113

Antibody Engineering and Therapeutics Conference  

PubMed Central

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.

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

114

[Antibody therapy for Alzheimer's disease].  

PubMed

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

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

2011-11-01

115

Targeting antibodies to the cytoplasm  

PubMed Central

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

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

2011-01-01

116

Commercial antibodies and their validation  

PubMed Central

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

Voskuil, JLA

2014-01-01

117

Therapeutic antibodies against cancer  

PubMed Central

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

Adler, Mark J.; Dimitrov, Dimiter S.

2012-01-01

118

Antibody-mediated radiotherapy  

SciTech Connect

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.

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

1985-05-01

119

Antibody Therapy for Pediatric Leukemia  

PubMed Central

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

Vedi, Aditi; Ziegler, David S.

2014-01-01

120

Novel Point-of-Care Test for Simultaneous Detection of Nontreponemal and Treponemal Antibodies in Patients with Syphilis ?  

PubMed Central

We describe a point-of-care immunochromatographic test for the simultaneous detection of both nontreponemal and treponemal antibodies in the sera of patients with syphilis that acts as both a screening and a confirmatory test. A total of 1,601 banked serum samples were examined by the dual test, and the results were compared to those obtained using a quantitative rapid plasma reagin (RPR) test and the Treponema pallidum passive particle agglutination (TP-PA) assay. Compared to the RPR test, the reactive concordance of the dual test nontreponemal line was 98.4% when the RPR titers of sera were ?1:2 and the nonreactive concordance was 98.6%. Compared to the TP-PA assay, the reactive and nonreactive concordances of the treponemal line were 96.5% and 95.5%, respectively. These results indicate that the dual test could be used for the serological diagnosis of syphilis in primary health care clinics or resource-poor settings and therefore improve rates of treatment where patients may fail to return for their laboratory results. PMID:20881177

Castro, Arnold R.; Esfandiari, Javan; Kumar, Shailendra; Ashton, Matthew; Kikkert, Susan E.; Park, Mahin M.; Ballard, Ronald C.

2010-01-01

121

Antibody biodistribution coefficients  

PubMed Central

Tissue vs. plasma concentration profiles have been generated from a physiologically-based pharmacokinetic model of monoclonal antibody (mAb). Based on the profiles, we hypothesized that a linear relationship between the plasma and tissue concentrations of non-binding mAbs could exist; and that the relationship may be generally constant irrespective of the absolute mAb concentration, time, and animal species being analyzed. The hypothesis was verified for various tissues in mice, rat, monkey, and human using mAb or antibody-drug conjugate tissue distribution data collected from diverse literature. The relationship between the plasma and various tissue concentrations was mathematically characterized using the antibody biodistribution coefficient (ABC). Estimated ABC values suggest that typically the concentration of mAb in lung is 14.9%, heart 10.2%, kidney 13.7%, muscle 3.97%, skin 15.7%, small intestine 5.22%, large intestine 5.03%, spleen 12.8%, liver 12.1%, bone 7.27%, stomach 4.98%, lymph node 8.46%, adipose 4.78%, brain 0.351%, pancreas 6.4%, testes 5.88%, thyroid 67.5% and thymus is 6.62% of the plasma concentration. The validity of using the ABC to predict mAb concentrations in different tissues of mouse, rat, monkey, and human species was evaluated by generating validation data sets, which demonstrated that predicted concentrations were within 2-fold of the observed concentrations. The use of ABC to infer tissue concentrations of mAbs and related molecules provides a valuable tool for investigating preclinical or clinical disposition of these molecules. It can also help eliminate or optimize biodistribution studies, and interpret efficacy or toxicity of the drug in a particular tissue. PMID:23406896

Shah, Dhaval K.; Betts, Alison M.

2013-01-01

122

Antibody Production by Single Cells  

Microsoft Academic Search

FAGREUS1 and others2,3 have shown that certain tissues from pre-sensitized animals can form antibody in vitro. This communication describes a technique whereby antibody production by single cells isolated in microdroplets can be detected. The technique is based on specific immobilization of Salmonella serotypes by anti-flagellar antibody. It was observed that single cells from a rat, simultaneously stimulated with two antigens,

G. J. V. Nossal; Joshua Lederberg

1958-01-01

123

Function-first antibody discovery  

PubMed Central

Therapeutic antibodies may mediate antineoplastic effects by altering the biological functions of their target, by directly stimulating the demise of cancer cells or by activating antibody-dependent immune effector mechanisms. We have recently provided in vivo proof-of-concept for a “function-first” target and drug discovery platform in which antibodies against a multitude of tumor-associated antigens are screened for biological effects in a target-unbiased manner. PMID:24083074

Frendéus, Björn

2013-01-01

124

Monoclonal antibody therapy of cancer  

Microsoft Academic Search

The most significant recent advances in the application of monoclonal antibodies (mAbs) to oncology have been the introduction and approval of bevacizumab (Avastin), an anti–vascular endothelial growth factor antibody, and of cetuximab (Erbitux), an anti–epidermal growth factor antibody. In combination with standard chemotherapy regimens, bevacizumab significantly prolongs the survival of patients with metastatic cancers of the colorectum, breast and lung.

Gregory P Adams; Louis M Weiner

2005-01-01

125

Monoclonal antibodies: versatile platforms for cancer immunotherapy  

Microsoft Academic Search

Antibodies are important therapeutic agents for cancer. Recently, it has become clear that antibodies possess several clinically relevant mechanisms of action. Many clinically useful antibodies can manipulate tumour-related signalling. In addition, antibodies exhibit various immunomodulatory properties and, by directly activating or inhibiting molecules of the immune system, antibodies can promote the induction of antitumour immune responses. These immunomodulatory properties can

Rishi Surana; Shangzi Wang; Louis M. Weiner

2010-01-01

126

Anti-flavin antibodies.  

PubMed Central

Antibodies were elicited to FAD by using the hapten N-6-(6-aminohexyl)-FAD conjugated to the immunogenic carrier protein bovine serum albumin. Cross-reactivity was determined by Ouchterlony double-diffusion analysis with N-6-(6-aminohexyl)-FAD coupled to rabbit serum albumin. Anti-FAD IgG was partially purified by (NH4)2SO4 precipitation followed by DEAE-cellulose/CM-cellulose and bovine serum albumin-agarose chromatography. The partially purified anti-FAD IgG fraction failed to inhibit the catalytic activities of the flavin-containing enzymes nitrate reductase, xanthine oxidase and succinate dehydrogenase, whereas enzyme activity could be inhibited by addition of antibodies elicited against the native proteins. However, the partially purified anti-FAD IgG fraction could be used as a highly sensitive and specific probe to detect proteins containing only covalently bound flavin, such as succinate dehydrogenase, p-cresol methylhydroxylase and monoamine oxidase, by immuno-blotting techniques. Detection limits were estimated to be of the order of femtomolar concentrations of FAD with increased sensitivity for the 8 alpha-N(3)-histidyl linkage compared with 8 alpha-O-tyrosyl substitution. Images Fig. 1. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:3109386

Barber, M J; Eichler, D C; Solomonson, L P; Ackrell, B A

1987-01-01

127

A revival of bispecific antibodies  

Microsoft Academic Search

Bispecific antibodies usually do not occur in nature but are constructed by recombinant DNA or cell-fusion technologies. Most are designed to recruit cytotoxic effector cells of the immune system effectively against pathogenic target cells. This complex task explains why, after more than 15 years of extensive research, many different formats of bispecific antibodies have been developed but only a few

Peter Kufer; Ralf Lutterbüse; Patrick A. Baeuerle

2004-01-01

128

Chemical generation of bispecific antibodies  

PubMed Central

Bispecific antibodies (BsAbs) are regarded as promising therapeutic agents due to their ability to simultaneously bind two different antigens. Several bispecific modalities have been developed, but their utility is limited due to problems with stability and manufacturing complexity. Here we report a versatile technology, based on a scaffold antibody and pharmacophore peptide heterodimers, that enables rapid generation and chemical optimization of bispecific antibodies, which are termed bispecific CovX-Bodies. Two different peptides are joined together using a branched azetidinone linker and fused to the scaffold antibody under mild conditions in a site-specific manner. Whereas the pharmacophores are responsible for functional activities, the antibody scaffold imparts long half-life and Ig-like distribution. The pharmacophores can be chemically optimized or replaced with other pharmacophores to generate optimized or unique bispecific antibodies. As a prototype, we developed a bispecific antibody that binds both vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang2) simultaneously, inhibits their function, shows efficacy in tumor xenograft studies, and greatly augments the antitumor effects of standard chemotherapy. This unique antiangiogenic bispecific antibody is in phase-1 clinical trials. PMID:21149738

Doppalapudi, Venkata R.; Huang, Jie; Liu, Dingguo; Jin, Ping; Liu, Bin; Li, Lingna; Desharnais, Joel; Hagen, Crystal; Levin, Nancy J.; Shields, Michael J.; Parish, Michelle; Murphy, Robert E.; Del Rosario, Joselyn; Oates, Bryan D.; Lai, Jing-Yu; Matin, Marla J.; Ainekulu, Zemeda; Bhat, Abhijit; Bradshaw, Curt W.; Woodnutt, Gary; Lerner, Richard A.; Lappe, Rodney W.

2010-01-01

129

Bispecific antibodies for cancer therapy  

PubMed Central

With 23 approvals in the US and other countries and four approvals outside US, antibodies are now widely recognized as therapeutic molecules. The therapeutic and commercial successes met by rituximab, trastuzumab, cetuximab and other mAbs have inspired antibody engineers to improve the efficacy of these molecules. Consequently, a new wave of antibodies with engineered Fc leading to much higher effector functions such as antibody-dependent cell-mediated cytotoxicity or complement-dependent cytotoxicity is being evaluated in the clinic, and several approvals are expected soon. In addition, research on a different class of antibody therapeutics, bispecific antibodies, has recently led to outstanding clinical results, and the first approval of the bispecific antibody catumaxomab, a T cell retargeting agent that was approved in the European Union in April 2009. This review describes the most recent advances and clinical study results in the field of bispecific antibodies, a new class of molecules that might outshine conventional mAbs as cancer immunotherapeutics in a near future. PMID:20073127

Baty, Daniel

2009-01-01

130

Endogenous Antibodies for Tumor Detection  

PubMed Central

The study of cancer immunology has provided diagnostic and therapeutic instruments through serum autoantibody biomarkers and exogenous monoclonal antibodies. While some endogenous antibodies are found within or surrounding transformed tissue, the extent to which this exists has not been entirely characterized. We find that in transgenic and xenograft mouse models of cancer, endogenous gamma immunoglobulin (IgG) is present at higher concentration in malignantly transformed organs compared to non-transformed organs in the same mouse or organs of cognate wild-type mice. The enrichment of endogenous antibodies within the malignant tissue provides a potential means of identifying and tracking malignant cells in vivo as they mutate and diversify. Exploiting these antibodies for diagnostic and therapeutic purposes is possible through the use of agents that bind endogenous antibodies. PMID:24875800

Rich, Barrie S.; Honeyman, Joshua N.; Darcy, David G.; Smith, Peter T.; Williams, Andrew R.; Lim, Irene Isabel P.; Johnson, Linda K.; Gönen, Mithat; Simon, Joel S.; LaQuaglia, Michael P.; Simon, Sanford M.

2014-01-01

131

Micromechanical antibody sensor  

DOEpatents

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.

Thundat, Thomas G. (Knoxville, TN); Jacobson, K. Bruce (Oak Ridge, TN); Doktycz, Mitchel J. (Knoxville, TN); Kennel, Stephen J. (Oak Ridge, TN); Warmack, Robert J. (Knoxville, TN)

2001-01-01

132

Taxonomic study of the genera Halogeometricum and Halosarcina: transfer of Halosarcina limi and Halosarcina pallida to the genus Halogeometricum as Halogeometricum limi comb. nov. and Halogeometricum pallidum comb. nov., respectively  

PubMed Central

Members of the haloarchaeal genera Halosarcina and Halogeometricum (family Halobacteriaceae) are closely related to each other and show 96.6–98?% 16S rRNA gene sequence similarity. This is higher than the accepted threshold value (95?%) to separate two genera, and a taxonomic study using a polyphasic approach of all four members of the two genera was conducted to clarify their relationships. Polar lipid profiles indicated that Halogeometricum rufum RO1-4T, Halosarcina pallida BZ256T and Halosarcina limi RO1-6T are related more to each other than to Halogeometricum borinquense CGMCC 1.6168T. Phylogenetic analyses using the sequences of three different genes (16S rRNA gene, rpoB? and EF-2) strongly supported the monophyly of these four species, showing that they formed a distinct clade, separate from the related genera Halopelagius, Halobellus, Haloquadratum, Haloferax and Halogranum. The results indicate that the four species should be assigned to the same genus, and it is proposed that Halosarcina pallida and Halosarcina limi be transferred to the genus Halogeometricum as Halogeometricum pallidum comb. nov. (type strain, BZ256T?=?KCTC 4017T?=?JCM 14848T) and Halogeometricum limi comb. nov. (type strain, RO1-6T?=?CGMCC 1.8711T?=?JCM 16054T). PMID:24097833

Qiu, Xing-Xing; Zhao, Mei-Lin; Han, Dong; Zhang, Wen-Jiao; Dyall-Smith, Mike L.

2013-01-01

133

Bispecific Antibodies from Hybrid Hybridoma  

Microsoft Academic Search

\\u000a Hybrid hybridomas (also termed quadromas or tetradomas) are man-made cell lines that secrete bispecific antibodies (bsAb)\\u000a with two different specificities being able to crosslink two distinct molecules. Such antibodies do not occur in nature and\\u000a have been originally developed to improve immunohistochemical staining procedures and immunoassays (Milstein and Cuello 1983;\\u000a Suresh et al. 1986). Interestingly, the fusion of two immunoglobulin-producing

Gerhard Moldenhauer

134

Bispecific Antibodies and Gene Therapy  

Microsoft Academic Search

\\u000a Gene therapy is the transfer of therapeutic genes, via gene transfer vectors, into patients for therapeutic purposes. Different\\u000a gene therapy strategies are being pursued, including long-term gene correction of monogenetic diseases, eradication of tumor\\u000a cells in cancer patients, or genetic vaccination for infectious diseases. Bispecific antibodies and gene therapy are connected\\u000a in two ways. First, bispecific antibodies are tools of

Dirk M. Nettelbeck

135

Antiphospholipid antibodies: specificity and pathophysiology.  

PubMed

Antiphospholipid antibodies are autoantibodies that can be detected in plasma or serum with phospholipid-dependent coagulation tests or solid-phase immunoassays. The presence of these autoantibodies is strongly associated with an increased risk for arterial and venous thrombosis, recurrent fetal loss and thrombocytopenia. This paradoxical association of the in vitro prolongation of clotting assays and in vivo thrombosis has stimulated the search for the real antigen to which the autoantibodies are directed. A large number of potential pathological mechanisms have been proposed, and although disturbance of a certain metabolic pathway by the antibodies can explain a thrombotic tendency in one patient, no general pathological mechanism explaining thrombosis in the whole patient population has been found. This suggests that the antiphospholipid antibodies are a heterogeneous group of autoantibodies and is supported by the recent observations that antiphospholipid antibodies are not directed against phospholipids alone but against a combination of phospholipids and phospholipid-binding proteins. Both the phospholipid and the protein are part of the antigen. For the detection of antiphospholipids in an ELISA set-up, beta 2-glycoprotein I is the protein cofactor. In the coagulation tests, beta 2-glycoprotein, as well as prothrombin, can act as cofactor. However, the presence of these two proteins as a part of the epitope of the antiphospholipid antibodies does not explain the thrombotic tendency in the patient group. We have found that more physiologically relevant cofactors such as protein C and protein S, for which it is known that a partial deficiency is correlated with a thrombotic tendency, can also act as cofactors for the binding of antiphospholipid antibodies. It is concluded that antiphospholipid antibodies are a heterogeneous group of autoantibodies with varying affinity for different protein-phospholipid complexes and that inhibition of the biological activity of the protein part of the complex determines the pathological capacity of the antibodies. PMID:8025348

de Groot, P G; Oosting, J D; Derksen, R H

1993-09-01

136

Monoclonal antibodies to the human mammary gland  

Microsoft Academic Search

Mouse monoclonal antibodies have been raised to the human milk fat globule membrane. The distribution of the antigens detected by four of the antibodies has been examined in formalin-fixed, paraffin-embedded human tissues by light microscopic immunocytochemistry. The four antibodies stain lactating breast and normal resting breast. Two exclusively stain the luminal membranes of breast epithelial cells. A third antibody stains

C. S. Foster; P. A. W. Edwards; E. A. Dinsdale; A. M. Neville

1982-01-01

137

Antibodies to watch in 2015.  

PubMed

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 7 antibody therapeutics (secukinumab, evolocumab, mepolizumab, dinutuximab, nivolumab, blinatumomab, 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

Reichert, Janice M

2015-01-01

138

Antibodies to watch in 2014  

PubMed Central

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

Reichert, Janice M

2014-01-01

139

Antibodies to watch in 2014.  

PubMed

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

Reichert, Janice M

2014-01-01

140

Avian Diagnostic and Therapeutic Antibodies  

SciTech Connect

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.

Bradley, David Sherman [UND SMHS] [UND SMHS

2012-12-31

141

Antibody-targeted radiation cancer therapy  

Microsoft Academic Search

Several monoclonal antibodies are now approved for cancer therapy, such as rituximab, an anti-CD20 monoclonal antibody for the treatment of B-cell non-Hodgkin's lymphoma. Such 'naked' antibodies can recruit the body's immune effector mechanisms to kill cells expressing the target of the antibody. In recent years, the linking of radionuclides to antibodies to either augment inherent activity or to exploit the

Diane E. Milenic; Erik D. Brady; Martin W. Brechbiel

2004-01-01

142

Production of recombinant antibodies using bacteriophages  

PubMed Central

Recombinant antibody fragments such as Fab, scFv, diabodies, triabodies, single domain antibodies and minibodies have recently emerged as potential alternatives to monoclonal antibodies, which can be engineered using phage display technology. These antibodies match the strengths of conventionally produced monoclonal antibodies and offer advantages for the development of immunodiagnostic kits and assays. These fragments not only retain the specificity of the whole monoclonal antibodies but also easy to express and produce in prokaryotic expression system. Further, these antibody fragments are genetically stable, less expensive, easy to modify in response to viral mutations and safer than monoclonal antibodies for use in diagnostic and therapeutic applications. This review describes the potential of antibody fragments generated using phage display and their use as diagnostic reagents. PMID:24883194

Shukra, A. M.; Sridevi, N. V.; Dev Chandran

2014-01-01

143

Uses of monoclonal antibody 8H9  

DOEpatents

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.

Cheung, Nai-Kong V.

2013-04-09

144

Epigenetics of the antibody response.  

PubMed

Epigenetic marks, such as DNA methylation, histone post-translational modifications and miRNAs, are induced in B cells by the same stimuli that drive the antibody response. They play major roles in regulating somatic hypermutation (SHM), class switch DNA recombination (CSR), and differentiation to plasma cells or long-lived memory B cells. Histone modifications target the CSR and, possibly, SHM machinery to the immunoglobulin locus; they together with DNA methylation and miRNAs modulate the expression of critical elements of that machinery, such as activation-induced cytidine deaminase (AID), as well as factors central to plasma cell differentiation, such as B lymphocyte-induced maturation protein-1 (Blimp-1). These inducible B cell-intrinsic epigenetic marks instruct the maturation of antibody responses. Their dysregulation plays an important role in aberrant antibody responses to foreign antigens, such as those of microbial pathogens, and self-antigens, such as those targeted in autoimmunity, and B cell neoplasia. PMID:23643790

Li, Guideng; Zan, Hong; Xu, Zhenming; Casali, Paolo

2013-09-01

145

Molecular-specific urokinase antibodies  

NASA Technical Reports Server (NTRS)

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.

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

2009-01-01

146

Antibodies to watch in 2013  

PubMed Central

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

Reichert, Janice M

2013-01-01

147

Rh Antibodies Detectable only by Enzyme Technique  

PubMed Central

The titration of Rh antibodies at intervals during pregnancy by various methods has led to evidence for the existence of an Rh antibody or antibodies detectable by an enzyme (papain) method but not by anti-human-globulin. Adsorption experiments show that this antibody is less readily absorbed by red cells than the other Rh antibodies unless the cells are pretreated with enzyme. This fact may possibly account for the finding of a negative or weakly positive anti-human-globulin test associated with moderate or high titres by enzyme techniques. The relationship of this antibody to the general immunization process in pregnant women is discussed. PMID:13886834

Dodd, Barbara E.; Eeles, Doreen A.

1961-01-01

148

Monoclonal Antibodies for the Treatment of Cancer  

PubMed Central

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

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

2012-01-01

149

Catalytic antibodies with acetylcholinesterase activity.  

PubMed

We describe three catalytic cholinesterase-like catalytic antibodies (Ab1), as well as anti-idiotypic (Ab2) and idiotypic (Ab3) antibodies, to one of the Ab1s. The Ab1s were raised against the human erythrocyte acetylcholinesterase (AChE), and are unusual in that they both recognise and resemble acetylcholinesterase in their catalytic activity. No contamination of the antibody preparations with either acetylcholinesterase or butyrylcholinesterase (BChE) was found. None of the Ab2s showed catalytic activity, whereas four Ab3s did (an incidence of 1.26% of all Ab3s). Although there is considerable resemblance between Ab1s and Ab3s, there are significant differences between the two groups. All the antibodies were inhibited by phenylmethylsulphonyl fluoride (PMSF), indicating the presence of a serine residue in their active sites, and were inhibited by the cholinesterase active site inhibitors iso-OMPA and pyridostigmine, suggesting the similarity of the sites to those of cholinesterases. The Ab3s resemble the Ab1s in their ability to hydrolyse both acetyl and butyrylthiocholine (BTCh). However, the Ab3s appear to be better catalysts, having significantly reduced K(m) values (for acetyl, but not for butyrylthiocholine) and increased turnover numbers (K(cat)), rate enhancements (K(cat)/K(uncat)) and K(cat)/K(m) ratios, for both substrates, although these values by no means approach those of the natural enzymes. The Ab1s appear to have structures resembling the anionic sites of cholinesterases, as shown by their reaction with the anionic site inhibitors (edrophonium and tetramethylammonium). No such reactions were observed in the Ab3s. None of the antibodies show evidence of the sites resembling the peripheral anionic site (PAS) of acetylcholinesterase. All the antibodies recognise, to varying degrees, the peripheral anionic site of acetylcholinesterase. This was shown by their ability to inhibit acetylcholinesterase, to compete with peripheral site inhibitors, and to block acetylcholinesterase-mediated cell adhesion, a property of this site. The results indicate idiotypic mimicry of a catalytic antibody's active site, and suggest that the development of the catalytic activity in the anti-acetylcholinesterase antibodies may be related to the structural features of the peripheral anionic site of acetylcholinesterase. PMID:12379349

Johnson, Glynis; Moore, Samuel W

2002-11-01

150

Antibody profiling sensitivity through increased reporter antibody layering  

DOEpatents

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.

Apel, William A; Thompson, Vicki S

2013-02-26

151

[Neuroimmunological diseases associated with VGKC complex antibodies].  

PubMed

Antibodies to voltage-gated potassium channels(VGKC) were first identified by radioimmunoassay of radioisotope labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were found only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in Morvan's syndrome and in a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins(for example LGI-1, Caspr-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now usually known as VGKC-complex antibodies. In general, LGI-1 antibodies are most common in limbic encephalitis with SIADH. Caspr-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. PMID:23777104

Watanabe, Osamu

2013-05-01

152

Antiphospholipid Antibodies: Findings at Arteriography  

Microsoft Academic Search

PURPOSE: The purpose of this study was to determine the frequency and types of abnor- malities at arteriography in patients with antiphospholipid antibodies (APA) and ischemic cerebrovascular events. METHODS: Twenty-three patients with APA and ischemic cerebrovascular events who un- derwent arteriography were identified. Patients over the age of 65 years were excluded. No patients met diagnostic criteria for systemic lupus

James M. Provenzale; Daniel P. Barboriak; Nancy B. Allen; Thomas L. Ortel

153

Antiphospholipid Antibodies and Stroke in Young Women  

Microsoft Academic Search

Background and Purpose—Antiphospholipid antibodies have been associated with ischemic stroke in some but not all studies. Methods—We performed a population-based case-control study examining antiphospholipid antibodies (anticardiolipin antibodies and lupus anticoagulants) using stored frozen sera and plasma in 160 cases and 340 controls enrolled in the Stroke Prevention in Young Women study. We evaluated for the presence of anticardiolipin antibody (IgG,

Robin L. Brey; Christian L. Stallworth; David L. McGlasson; Marcella A. Wozniak; Robert J. Wityk; Barney J. Stern; Michael A. Sloan; Roger Sherwin; Thomas R. Price; Richard F. Macko; Constance J. Johnson; Christopher J. Earley; David W. Buchholz; J. Richard Hebel; Steven J. Kittner

154

Therapeutic antibodies for autoimmunity and inflammation  

Microsoft Academic Search

The development of therapeutic antibodies has evolved over the past decade into a mainstay of therapeutic options for patients with autoimmune and inflammatory diseases. Substantial advances in understanding the biology of human diseases have been made and tremendous benefit to patients has been gained with the first generation of therapeutic antibodies. The lessons learnt from these antibodies have provided the

Andrew C. Chan; Paul J. Carter

2010-01-01

155

Anti-DNA antibodies in SLE  

SciTech Connect

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.

Voss, E.W.

1988-01-01

156

Original article Monoclonal antibodies against goldfish  

E-print Network

immunoglobulin and antibody levels by ELISA in carp (Cyprinus carpio) AK Siwicki C Vergnet J Charlemagne M Dunier decreased until day 28. monoclonal antibody / ELISA / ELISPOT / antibody-secreting cells / Cyprinus carpio suite. anticorps monoc/ona//EL/S/Cyprinus carpio

Paris-Sud XI, Université de

157

Recombinant antibodies and their use in biosensors.  

PubMed

Inexpensive, noninvasive immunoassays can be used to quickly detect disease in humans. Immunoassay sensitivity and specificity are decidedly dependent upon high-affinity, antigen-specific antibodies. Antibodies are produced biologically. As such, antibody quality and suitability for use in immunoassays cannot be readily determined or controlled by human intervention. However, the process through which high-quality antibodies can be obtained has been shortened and streamlined by use of genetic engineering and recombinant antibody techniques. Antibodies that traditionally take several months or more to produce when animals are used can now be developed in a few weeks as recombinant antibodies produced in bacteria, yeast, or other cell types. Typically most immunoassays use two or more antibodies or antibody fragments to detect antigens that are indicators of disease. However, a label-free biosensor, for example, a quartz-crystal microbalance (QCM) needs one antibody only. As such, the cost and time needed to design and develop an immunoassay can be substantially reduced if recombinant antibodies and biosensors are used rather than traditional antibody and assay (e.g. enzyme-linked immunosorbant assay, ELISA) methods. Unlike traditional antibodies, recombinant antibodies can be genetically engineered to self-assemble on biosensor surfaces, at high density, and correctly oriented to enhance antigen-binding activity and to increase assay sensitivity, specificity, and stability. Additionally, biosensor surface chemistry and physical and electronic properties can be modified to further increase immunoassay performance above and beyond that obtained by use of traditional methods. This review describes some of the techniques investigators have used to develop highly specific and sensitive, recombinant antibody-based biosensors for detection of antigens in simple or complex biological samples. PMID:22159424

Zeng, Xiangqun; Shen, Zhihong; Mernaugh, Ray

2012-04-01

158

Production of Monoclonal Antibody against Human Nestin  

PubMed Central

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

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

159

Solubility evaluation of murine hybridoma antibodies  

PubMed Central

The successful development of antibody therapeutics depends on the molecules having properties that are suitable for manufacturing, as well as use by patients. Because high solubility is a desirable property for antibodies, screening for solubility has become an essential step during the early candidate selection process. In considering the screening process, we formed a hypothesis that hybridoma antibodies are filtered by nature to possess high solubility and tested this hypothesis using a large number of murine hybridoma-derived antibodies. Using the cross-interaction chromatography (CIC) method, we screened the solubility of 92 murine hybridoma-derived monoclonal antibodies and found that all of these molecules exhibited CIC profiles that are indicative of high solubility (>100mg/mL). Further investigations revealed that variable region N-linked glycosylation or isoelectric parameters are unlikely to contribute to the high solubility of these antibodies. These results support the general hypothesis that hybridoma monoclonal antibodies are highly soluble. PMID:22531448

Spencer, Stacey; Bethea, Deidra; Raju, T. Shantha; Giles-Komar, Jill; Feng, Yiqing

2012-01-01

160

Monoclonal antibodies to intermediate filament proteins of human cells: unique and cross- reacting antibodies  

PubMed Central

Monoclonal antibodies were generated against the intermediate filament proteins of different human cells. The reactivity of these antibodies with the different classes of intermediate filament proteins was determined by indirect immunofluorescence on cultured cells, immunologic indentification on SDS polyacrylamide gels (“wester blot” experiments), and immunoperoxidase assays on intact tissues. The following four antibodies are described: (a) an antivimentin antibody generated against human fibroblast cytoskeleton; (b), (c) two antibodies that recognize a 54-kdalton protein in human hepatocellular carcinoma cells; and (d) an antikeratin antibody made to stratum corneum that recognizes proteins of molecular weight 66 kdaltons and 57 kdaltons. The antivimentin antibody reacts with vimentin (58 kdaltons), glial fibrillary acidic protein (GFAP), and keratins from stratum corneum, but does not recognize hepatoma intermediate filaments. In immunofluorescence assays, the antibody reacts with mesenchymal cells and cultured epithelial cells that express vimentin. This antibody decorates the media of blood vessels in tissue sections. One antihepatoma filament antibody reacts only with the 54 kdalton protein of these cells and, in immunofluorescence and immunoperoxidase assays, only recognizes epithelial cells. It reacts with almost all nonsquamous epithelium. The other antihepatoma filament antibody is much less selective, reacting with vimentin, GFAP, and keratin from stratum corneum. This antibody decorates intermediate filaments of both mesenchymal and epithelial cells. The antikeratin antibody recognizes 66-kdalton and 57-kdalton proteins in extracts of stratum corneum and also identifies proteins of similar molecular weights in all cells tested. However, by immunofluorescence, this antibody decorates only the intermediate filaments of epidermoid carcinoma cells. When assayed on tissue sections, the antibody reacts with squamous epithelium and some, but not all, nonsquamous epithelium. Therefore this antistratum corneum antibody and the anti-54-kdalton antibody identify unique epitopes present in the various cytokeratin molecules of epithelial cells. None of the hybridoma antibodies react with neurofilament proteins. The different patterns of reactivity of these antibodies suggest that many of the immunologically distinct intermediate filament proteins contain common antigenic determinants. PMID:6183272

Gown, AM; Vogel, AM

1982-01-01

161

Radiolabeling antibodies with holmium-166.  

PubMed

We report the preliminary results from radiolabeling of a chelate-conjugated antibody with 166Ho produced from the beta(-)-decay of 166Dy. Ho-166 was separated from mg quantities of Dy target by reverse phase ion-exchange chromatography employing a cation exchange HPLC column and 0.085 M alpha-HIBA at pH = 4.3 as eluent. Evaporation to dryness of 166Ho fraction (up to 25 mL) and thermal decomposition of alpha-HIBA yielded 166Ho in a dry state which was then solubilized in 0.5 mL of 0.1 M HCl. Subsequent radiolabeling of CHX-B-DTPA conjugated 135-14 monoclonal antibodies with purified 166 Ho was readily achieved with approximately 80% efficiency and with a specific activity of 3-4 mCi of 166Ho per mg of protein. 166Ho-antibody conjugates are stable with regards to transferrin challenge for a period of 50 h. Further, it was shown that any Fe3+ ions present in alpha-HIBA as an impurity interfere with the labeling. PMID:9106989

Dadachova, E; Mirzadeh, S; Smith, S V; Knapp, F F; Hetherington, E L

1997-04-01

162

Single-Chain Antibody Library  

DOE Data Explorer

Researchers at Pacific Northwest National Laboratory (PNNL) have constructed a nonimmune library consisting of 109 human antibody scFv fragments, which have been cloned and expressed on the surface of yeast. Nanomolar-affinity scFvs are routinely obtained by magnetic bead screening and flow cytometric sorting. The yeast library can be amplified 1010 fold without measurable loss of clonal diversity. This allows for indefinite expansion of the library. All scFv clones can be assessed directly on the yeast cell surface by immunofluorescent labeling and flow cytometry, obviating separate subcloning, expression, and purification steps. The ability to use multiplex library screening demonstrates the utility of this approach for high-throughput antibody isolation for proteomic applications. The yeast library may be used for research projects or teaching performed for U.S. Government purposes only. If you would like to request an aliquot of the single-chain antibody library for your research, please print and fill out the Materials Transfer Agreement (MTA) [PDF, 20K]. The website provides the contact information for mailing the MTA. [copied from http://www.sysbio.org/dataresources/singlechain.stm

Baird, Cheryl

163

Improved monoclonal antibodies to halodeoxyuridine  

DOEpatents

The development, method of production, characterization and methods of use of two hybridomas, CIdU-1 (ATCC Accession No. HB-8321) and CIdU-2 (ATCC Accession No. HB-8320), are described. These secrete IgG/sub 1/(K) immunoglobulins that react with halodeoxyuridine (HdU or halodU) such as bromo, chloro, fluoro and iodo deoxyuridine (BrdU, CldU, FdU and IdU), whether these are free in solution or incorporated into single stranded DNA in whole cells. The antibodies do not react with naturally occurring free nucleic acids or with deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) polymers. These antibodies are suitable for use in enzyme immunoassays for free CldU, FdU, IdU and BrdU and for detecting cells with these nucleotides incorporated into them. The monoclonal antibodies are useful in the detection of the sensitivity of tumor cells to specific chemotherapeutic agents, in the measurement of the rate of cellular DNA synthesis, in the measurement of the rate of proliferation of normal and malignant cells and in the detection of HPRT deficiency in cells. 1 tab.

Vanderlaan, M.; Dolbeare, F.A.; Gray, J.W.; Thomas, C.B.

1983-10-18

164

Generation of monospecific antibodies based on affinity capture of polyclonal antibodies.  

PubMed

A method is described to generate and validate antibodies based on mapping the linear epitopes of a polyclonal antibody followed by sequential epitope-specific capture using synthetic peptides. Polyclonal antibodies directed towards four proteins RBM3, SATB2, ANLN, and CNDP1, potentially involved in human cancers, were selected and antibodies to several non-overlapping epitopes were generated and subsequently validated by Western blot, immunohistochemistry, and immunofluorescence. For all four proteins, a dramatic difference in functionality could be observed for these monospecific antibodies directed to the different epitopes. In each case, at least one antibody was obtained with full functionality across all applications, while other epitope-specific fractions showed no or little functionality. These results present a path forward to use the mapped binding sites of polyclonal antibodies to generate epitope-specific antibodies, providing an attractive approach for large-scale efforts to characterize the human proteome by antibodies. PMID:21898641

Hjelm, Barbara; Forsström, Björn; Igel, Ulrika; Johannesson, Henrik; Stadler, Charlotte; Lundberg, Emma; Ponten, Fredrik; Sjöberg, Anna; Rockberg, Johan; Schwenk, Jochen M; Nilsson, Peter; Johansson, Christine; Uhlén, Mathias

2011-11-01

165

Distinction between MOG antibody-positive and AQP4 antibody-positive NMO spectrum disorders  

PubMed Central

Objective: To evaluate clinical features among patients with neuromyelitis optica spectrum disorders (NMOSD) who have myelin oligodendrocyte glycoprotein (MOG) antibodies, aquaporin-4 (AQP4) antibodies, or seronegativity for both antibodies. Methods: Sera from patients diagnosed with NMOSD in 1 of 3 centers (2 sites in Brazil and 1 site in Japan) were tested for MOG and AQP4 antibodies using cell-based assays with live transfected cells. Results: Among the 215 patients with NMOSD, 7.4% (16/215) were positive for MOG antibodies and 64.7% (139/215) were positive for AQP4 antibodies. No patients were positive for both antibodies. Patients with MOG antibodies represented 21.1% (16/76) of the patients negative for AQP4 antibodies. Compared with patients with AQP4 antibodies or patients who were seronegative, patients with MOG antibodies were more frequently male, had a more restricted phenotype (optic nerve more than spinal cord), more frequently had bilateral simultaneous optic neuritis, more often had a single attack, had spinal cord lesions distributed in the lower portion of the spinal cord, and usually demonstrated better functional recovery after an attack. Conclusions: Patients with NMOSD with MOG antibodies have distinct clinical features, fewer attacks, and better recovery than patients with AQP4 antibodies or patients seronegative for both antibodies. PMID:24415568

Sato, Douglas Kazutoshi; Callegaro, Dagoberto; Lana-Peixoto, Marco Aurelio; Waters, Patrick J.; Jorge, Frederico M. de Haidar; Takahashi, Toshiyuki; Nakashima, Ichiro; Apostolos-Pereira, Samira Luisa; Talim, Natalia; Simm, Renata Faria; Lino, Angelina Maria Martins; Misu, Tatsuro; Leite, Maria Isabel; Aoki, Masashi

2014-01-01

166

ANTIBODY SYNTHESIS AT THE CELLULAR LEVEL  

PubMed Central

The specific suppressing activity of passively administered antibody on 7S antibody synthesis against sheep and chicken red blood cells has been investigated at the cellular level using the indirect hemolytic agar-plaque technique. 7S antibody production was found to be sensitive to antibody-induced suppression. No inhibitory effect of transferred antibody was seen until 48 to 72 hr after administration. This indicates that the action of antibody is not by direct suppression of synthesis of already committed cells but rather by removal from the system of the stimulus for maintenance of 7S synthesis. The sensitivity of the 7S system to inhibition decreases with time after immunization but significant specific suppression could still be obtained if transfer of antibody was delayed until 40 days after immunization. The present findings emphasize the role of antibody as a feedback factor during a substantial postpeak period of 7S antibody synthesis and suggest an important role of antigen in stabilizing the 7S antibody production. PMID:5926303

Wigzell, Hans

1966-01-01

167

Postnatal decline of maternally acquired rubella antibodies  

PubMed Central

The postnatal decline of maternally acquired rubella antibody was studied in a large group of infants. A high degree of variability was found in the rate of antibody decline (half-life). Ninety-two babies had rubella antibody half-lives lying between 14 and 70 days and three had values considerably higher. There was no significant difference between the rubella antibody half-lives of the sexes. The antibody titre at birth was weakly correlated with both birth weight and gestational age. There was a highly significant positive correlation between the baby's antibody titre at birth and that of its mother. There was a positive relationship between the half-life and the persistence of rubella antibody. Some babies had no detectable antibody by 2 months whereas others still possessed antibody at 9 months. It was found that the relationship between the half-life and the rubella antibody titre at or near birth could be described by a rectangular hyperbola. PMID:5272346

Cloonan, M. J.; Hawkes, R. A.; Stevens, L. H.

1970-01-01

168

Antibodies for molecular imaging of cancer.  

PubMed

Antibodies have attained a central role as targeted therapeutics, with several significant drugs on the market and many more in clinical development for oncological applications. Expansion of the role of antibodies in cancer imaging has been accelerated by a number of factors, including the recognition that antibodies can provide a powerful class of molecular imaging probes for interrogating cell surfaces in vivo. Identification of relevant cell surface biomarkers as imaging targets, coupled with advances in antibody technology, facilitate the generation of antibodies optimized for noninvasive imaging. Developments in imaging instrumentation and radionuclide availability have paved the way for broader evaluation and implementation of radioimmunoscintigraphy and immunoPET. Antibody imaging can provide a sensitive, noninvasive means for molecular characterization of cell surface phenotype in vivo, which can in turn guide diagnosis, prognosis, therapy selection, and monitoring of treatment in cancer. PMID:18536559

Wu, Anna M; Olafsen, Tove

2008-01-01

169

Multi-specific antibodies for cancer immunotherapy.  

PubMed

Targeted treatment of cancer with monoclonal antibodies has added to the beneficial outcome of patients. In an attempt to improve anti-tumor activity of monoclonal antibodies, multi-specific antibodies have entered the research arena. To date, only a few multi-specific constructs have entered phase III clinical trials, in contrast to classical monoclonal antibodies, which are the standard first-line therapy in several tumor entities. In this review, we will assess selected multi-specific antibodies in pre-clinical and clinical development that may be new treatment options for cancer patients in the very near future. We will further evaluate therapy modalities including the timely distribution or the combination of various therapeutic approaches and assess the potential role of multi-specific antibodies in cancer treatment. PMID:24638872

Jachimowicz, Ron D; Borchmann, Sven; Rothe, Achim

2014-08-01

170

Radioimmunotherapy of malignancy using antibody targeted radionuclides.  

PubMed Central

Antibodies directed against tumour associated antigens provide a means for delivering preferentially cytotoxic radionuclides to the cells of primary and secondary tumours. The factors that influence the effectiveness of the radiation in the tumour compared with its effect on the radiosensitive normal tissues include the specificity of the antibody, the distribution of targeted energy within the tumour and the host's response to the injected foreign antibody. Recently some encouraging results from clinical trials of radioimmunotherapy have been reported in the literature. There is a continual search for more avid and specific antibodies, and the techniques of genetic engineering are being applied to the problem of reducing the antigenicity and mass of the carrier antibody. The improved efficiency of the labelled antibody needs to be supplemented by an identification of those tumours most likely to respond to this form of therapy. PMID:3542006

Cobb, L. M.; Humm, J. L.

1986-01-01

171

Generation of antibodies against membrane proteins.  

PubMed

The monoclonal antibody has become an important therapeutic in the treatment of both hematological malignancies and solid tumors. The recent success of antibody-drug conjugates (ADCs) has broadened the extent of the potential target molecules in cancer immunotherapy. As a result, even molecules of low abundance have become targets for cytotoxic reagents. The multi-pass membrane proteins are an emerging target for the next generation antibody therapeutics. One outstanding challenge is the difficulty in preparing a sufficient amount of these membrane proteins so as to be able to generate the functional antibody. We have pursued the expression of various membrane proteins on the baculovirus particle and the utilization of displayed protein for immunization. The strong antigenicity of the virus acts either as a friend or foe in the making of an efficient antibody against an immunologically tolerant antigen. This article is part of a Special Issue entitled: Recent advances in molecular engineering of antibody. PMID:25135856

Hamakubo, Takao; Kusano-Arai, Osamu; Iwanari, Hiroko

2014-11-01

172

Alternative Scaffolds as Bispecific Antibody Mimetics  

Microsoft Academic Search

\\u000a The use of non-immunoglobulin-based protein scaffolds for engineering of specific recognition was first described some 15\\u000a years ago and has matured as a discipline in parallel with the rapidly expanding monoclonal antibody field. As bispecific\\u000a antibodies and antibody fragments have come into focus lately, the corresponding development of bispecific alternative scaffolds\\u000a is also emerging. Here, the concept of alternative scaffold

John Löfblom; Fredrik Y. Frejd

173

Recombinant Bispecific Antibodies for Cancer Therapy  

Microsoft Academic Search

\\u000a Bispecific antibodies are molecules capable of simultaneously binding to two different antigens. While initially bispecific\\u000a antibodies have been developed mainly for cellular cancer immunotherapy through retargeting of effector cells to tumor cells,\\u000a recent developments include also dual targeting strategies and the retargeting of effector molecules, e.g. in radioimmunotherapy.\\u000a In addition to various applications, a plethora of bispecific antibody formats have

Dafne Müller; Roland E. Kontermann

174

The Human Antibody Response Against WNV  

Microsoft Academic Search

\\u000a Experimental evidence has shown that antibody responses to West Nile virus (WNV) are critical for protection from WNV-mediated\\u000a disease. Antibody responses are also an important immune correlate of protection for the clinical evaluation of WNV vaccines.\\u000a However, little direct study has been carried out on the characteristics of the human antibody response to natural WNV infection.\\u000a Preliminary evidence suggests that

Mark Throsby; Jaap Goudsmit; John de Kruif

175

ATYPICAL ANTIBODY RESPONSES IN DENGUE VACCINE RECIPIENTS  

Microsoft Academic Search

Eight of 69 (12%) healthy adult volunteers vaccinated with monovalent live-attenuated dengue virus (DENV) vaccine candidates had atypical antibody responses, with depressed IgM:IgG antibody ratios and induction of high-titer hemagglutination-inhibiting and neutralizing (NT) antibodies to all four DENV serotypes. These features suggested flavivirus exposure prior to DENV vaccination, yet no volunteer had a history of previous flavivirus infection, flavivirus vaccination,

N. KANESA-THASAN; W. SUN; G. V. LUDWIG; C. ROSSI; J. R. PUTNAK; J. A. MANGIAFICO; B. L. INNIS; R. EDELMAN

176

Haptens, bioconjugates, and antibodies for penthiopyrad immunosensing.  

PubMed

Haptens, bioconjugates, and antibodies for highly sensitive immunochemical analysis of the new-generation fungicide penthiopyrad are described. Two haptens with equivalent carboxylated linkers were prepared, and the purified active esters were efficiently coupled to proteins. The results revealed slightly different antibody-eliciting capacities for the two synthetic derivatives. All of the produced antibodies were specific for penthiopyrad, and showed affinity values in the nanomolar range. PMID:25197742

Ceballos-Alcantarilla, Eric; Abad-Fuentes, Antonio; Aloisio, Vincenzo; Agulló, Consuelo; Abad-Somovilla, Antonio; Mercader, Josep V

2014-11-01

177

Passive antibody therapy for infectious diseases  

Microsoft Academic Search

Antibody-based therapies are currently undergoing a renaissance. After being developed and then largely abandoned in the twentieth century, many antibody preparations are now in clinical use. However, most of the reagents that are available target non-infectious diseases. Interest in using antibodies to treat infectious diseases is now being fuelled by the wide dissemination of drug-resistant microorganisms, the emergence of new

Ekaterina Dadachova; Liise-anne Pirofski; Arturo Casadevall

2004-01-01

178

Production of chimeric heavy-chain antibodies.  

PubMed

Antibody has become a major category of therapeutics. However, IgG, the primary molecular format of existing antibody drugs, has some major shortcomings such as undesirable pharmacokinetics, high dose requirement, and high production cost, partially due to its large molecular size. Much efforts have been made to address these issues, which usually led to antibodies or antibody fragments with smaller size. However, in most cases these changes also resulted in complete or partial deletion of fragment crystallizable (Fc), which is known to be crucial for a long serum half-life through binding to FcRn and antibody-mediated cell killing through binding to Fcgamma receptors and complement. Single-domain antibodies (sdAbs) derived from camelid heavy-chain antibodies (HCAbs) provide an excellent building block for constructing antibodies with moderate size yet with an intact Fc. We describe in this chapter the construction, production, and purification of chimeric HCAbs (cHCAbs), that is, fusion of camelid sdAb to human Fc. The cHCAb has a molecular size approximately half that of IgG (80 kDa vs. 150 kDa). Production is achieved through a transient expression with a human embryonic kidney (HEK) expression system, which can rapidly provide hundreds of milligrams to low-gram quantities of soluble and glycosylated recombinant antibodies for early-stage drug development. PMID:19252853

Zhang, Jianbing; MacKenzie, Roger; Durocher, Yves

2009-01-01

179

Monoclonal antibodies that detect live salmonellae.  

PubMed Central

Nine immunoglobulin G and nine immunoglobulin M murine monoclonal antibody-producing hybridomas reactive with live Salmonella bacteria were obtained from several fusions of immune spleen cells and Sp2/0 myeloma cells. The antibodies were selected by the magnetic immunoluminescence assay. The monoclonal antibodies were reactive with serogroups A, B, C1, C2, D, E, and K and Salmonella choleraesuis subsp. diarizonae. Each monoclonal antibody proved to be reactive with a distinct serotype. Clinical isolates belonging to these Salmonella serogroups could be detected. Reactivity with non-Salmonella bacteria proved to be minor. Images PMID:1476430

Torensma, R; Visser, M J; Aarsman, C J; Poppelier, M J; van Beurden, R; Fluit, A C; Verhoef, J

1992-01-01

180

Reconciling the structural attributes of avian antibodies.  

PubMed

Antibodies are high value therapeutic, diagnostic, biotechnological, and research tools. Combinatorial approaches to antibody discovery have facilitated access to unique antibodies by surpassing the diversity limitations of the natural repertoire, exploitation of immune repertoires from multiple species, and tailoring selections to isolate antibodies with desirable biophysical attributes. The V-gene repertoire of the chicken does not utilize highly diverse sequence and structures, which is in stark contrast to the mechanism employed by humans, mice, and primates. Recent exploitation of the avian immune system has generated high quality, high affinity antibodies to a wide range of antigens for a number of therapeutic, diagnostic and biotechnological applications. Furthermore, extensive examination of the amino acid characteristics of the chicken repertoire has provided significant insight into mechanisms employed by the avian immune system. A paucity of avian antibody crystal structures has limited our understanding of the structural consequences of these uniquely chicken features. This paper presents the crystal structure of two chicken single chain fragment variable (scFv) antibodies generated from large libraries by phage display against important human antigen targets, which capture two unique CDRL1 canonical classes in the presence and absence of a non-canonical disulfide constrained CDRH3. These structures cast light on the unique structural features of chicken antibodies and contribute further to our collective understanding of the unique mechanisms of diversity and biochemical attributes that render the chicken repertoire of particular value for antibody generation. PMID:24737329

Conroy, Paul J; Law, Ruby H P; Gilgunn, Sarah; Hearty, Stephen; Caradoc-Davies, Tom T; Lloyd, Gordon; O'Kennedy, Richard J; Whisstock, James C

2014-05-30

181

6th Annual European Antibody Congress 2010  

PubMed Central

The 6th European Antibody Congress (EAC), organized by Terrapinn Ltd., was held in Geneva, Switzerland, which was also the location of the 4th and 5th EAC.1,2 As was the case in 2008 and 2009, the EAC was again the largest antibody congress held in Europe, drawing nearly 250 delegates in 2010. Numerous pharmaceutical and biopharmaceutical companies active in the field of therapeutic antibody development were represented, as were start-up and academic organizations and representatives from the US Food and Drug Administration (FDA). The global trends in antibody research and development were discussed, including success stories of recent marketing authorizations of golimumab (Simponi®) and canakinumab (Ilaris®) by Johnson & Johnson and Novartis, respectively, updates on antibodies in late clinical development (obinutuzumab/GA101, farletuzumab/MORAb-003 and itolizumab/T1 h, by Glycart/Roche, Morphotek and Biocon, respectively) and success rates for this fast-expanding class of therapeutics (Tufts Center for the Study of Drug Development). Case studies covering clinical progress of girentuximab (Wilex), evaluation of panobacumab (Kenta Biotech), characterization of therapeutic antibody candidates by protein microarrays (Protagen), antibody-drug conjugates (sanofi-aventis, ImmunoGen, Seattle Genetics, Wyeth/Pfizer), radio-immunoconjugates (Bayer Schering Pharma, Université de Nantes) and new scaffolds (Ablynx, AdAlta, Domantis/GlaxoSmithKline, Fresenius, Molecular Partners, Pieris, Scil Proteins, Pfizer, University of Zurich) were presented. Major antibody structural improvements were showcased, including the latest selection engineering of the best isotypes (Abbott, Pfizer, Pierre Fabre), hinge domain (Pierre Fabre), dual antibodies (Abbott), IgG-like bispecific antibodies (Biogen Idec), antibody epitope mapping case studies (Eli Lilly), insights in Fc?RII receptor (University of Cambridge), as well as novel tools for antibody fragmentation (Genovis). Improvements of antibody druggability (Abbott, Bayer, Pierre Fabre, Merrimack, Pfizer), enhancing IgG pharmacokinetics (Abbott, Chugai), progress in manufacturing (Genmab, Icosagen Cell Factory, Lonza, Pierre Fabre) and the development of biosimilar antibodies (Biocon, Sandoz, Triskel) were also discussed. Last but not least, identification of monoclonal antibodies (mAbs) against new therapeutic targets (Genentech, Genmab, Imclone/Lilly, Vaccinex) including Notch, cMet, TGF?RII, SEMA4D, novel development in immunotherapy and prophylaxis against influenza (Crucell), anti-tumor activity of immunostimulatory antibodies (MedImmune/Astra Zeneca) and translations to clinical studies including immunogenicity issues (Amgen, Novartis, University of Debrecen) were presented. PMID:21441785

2011-01-01

182

Uses of monoclonal antibody 8H9  

DOEpatents

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 a method of inhibiting the growth of tumor cells comprising contacting said tumor cells with an appropriate amount of monoclonal antibody 8H9 or a derivative thereof.

Cheung, Nai-Kong V

2013-08-06

183

Monoclonal Antibody That Defines Human Myoepithelium  

NASA Astrophysics Data System (ADS)

We have isolated a mouse monoclonal antibody that, upon immunohistochemical localization in frozen sections, displays specificity for human myoepithelial cells in the resting mammary gland, sweat glands, and salivary glands. Furthermore, this antibody was strongly and homogeneously reactive with frozen sections of 3 of 60 breast carcinoma specimens. Using immunolocalization techniques in conjunction with polyacrylamide gel electrophoresis, we have determined that the reactivity of this monoclonal antibody is directed toward a 51,000-dalton keratin polypeptide. The potential uses of this antibody in the prognosis of human mammary carcinoma and in understanding the role of the myoepithelium in development and differentiation are discussed.

Dairkee, Shahnaz Hashmi; Blayney, Carlene; Smith, Helene S.; Hackett, Adeline J.

1985-11-01

184

Preparation of astatine-labeled monoclonal antibodies  

SciTech Connect

In the cationic state astatine forms a stable complex with diethylenetriaminepentaacetic acid. Thanks to this complex, astatine can be bound to monoclonal antibodies of the RYa{sub 1} type. The most favorable conditions for preparing astatine-labeled antibodies are established. The chromatographic analysis and electromigration experiments showed that astatine is firmly linked to a biomolecule in vitro and it did not escape from labeled monoclonal antibodies even under treatment with such highly effective astatine-complexing agent as thiourea. The immune activity of astatine-labeled antibodies did not change even after 20 h.

Milesz, S.; Norseev, Yu.V.; Szucs, Z. [Joint Inst. for Nuclear Research, Dubna (Russian Federation)]|[Central Inst. of Physical Research, Budapest (Hungary)

1995-07-01

185

Camel Single-domain Antibodies as Modular Building Units in Bispecific and Bivalent Antibody Constructs  

Microsoft Academic Search

Single-domain antibodies against various antigens are isolated from the unique heavy-chain antibodies of immunized camels and llamas. These minimal sized binders are very robust and bind the antigen with high affinity in a monomeric state. We evaluated the feasibil- ity to produce soluble, functional bispecific and bivalent antibodies in Escherichia coli with camel single-domain antibody fragments as building blocks. Two

Katja Els Conrath; Mark Lauwereys; Lode Wyns; Serge Muyldermans

2001-01-01

186

Engineered antibody fragments and the rise of single domains  

Microsoft Academic Search

With 18 monoclonal antibody (mAb) products currently on the market and more than 100 in clinical trials, it is clear that engineered antibodies have come of age as biopharmaceuticals. In fact, by 2008, engineered antibodies are predicted to account for >30% of all revenues in the biotechnology market. Smaller recombinant antibody fragments (for example, classic monovalent antibody fragments (Fab, scFv))

Philipp Holliger; Peter J Hudson

2005-01-01

187

Vibriobactin Antibodies: A Vaccine Strategy  

PubMed Central

A new target strategy in the development of bacterial vaccines, the induction of antibodies to microbial outer membrane ferrisiderophore complexes, is explored. A vibriobactin (VIB) analogue, with a thiol tether, 1-(2,3-dihydroxybenzoyl)-5,9-bis[[(4S,5R)-2-(2,3-dihydroxyphenyl)-4,5-dihydro-5-methyl-4-oxazolyl]carbonyl]-14-(3-mercaptopropanoyl)-1,5,9,14-tetraazatetradecane, was synthesized and linked to ovalbumin (OVA) and bovine serum albumin (BSA). The antigenicity of the VIB microbial iron chelator conjugates and their iron complexes was evaluated. When mice were immunized with the resulting OVA-VIB conjugate, a selective and unequivocal antigenic response to the VIB hapten was observed; IgG monoclonal antibodies specific to the vibriobactin fragment of the BSA and OVA conjugates were isolated. The results are consistent with the idea that the isolated adducts of siderophores covalently linked to their bacterial outer membrane receptors represent a credible target for vaccine development. PMID:19492834

Bergeron, Raymond J.; Bharti, Neelam; Singh, Shailendra; McManis, James S.; Wiegand, Jan; Green, Linda G.

2010-01-01

188

Passive antibody transfer in chickens to model maternal antibody after avian influenza vaccination  

Technology Transfer Automated Retrieval System (TEKTRAN)

Birds transfer maternal antibodies (MAb) to their offspring through the egg yolk where the antibody is absorbed and enters the circulatory system. Maternal antibodies provide early protection from disease, but may interfere with the vaccination efficacy in the chick. MAb are thought to interfere wit...

189

The production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi  

Microsoft Academic Search

In this review we will focus on the current status and views concerning the production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi. We will focus on single-chain antibody fragment production (scFv and VHH) by these lower eukaryotes and the possible applications of these proteins. Also the coupling of fragments to relevant enzymes or other components

Vivi Joosten; Christien Lokman; Cees AMJJ van den Hondel; Peter J Punt

2003-01-01

190

Passive antibody transfer in chickens to model maternal antibody after avian influenza vaccination  

Technology Transfer Automated Retrieval System (TEKTRAN)

Birds transfer maternal antibodies (MAb) to their offspring through the egg yolk where the antibody is absorbed and enters the circulatory system. These maternal antibodies, depending on the pathogen, can provide early protection from some diseases, but it may also interfere with the vaccination re...

191

Reactivity patterns of antiphosphilipid antibodies and endothelial cells: Effect of antiendothelial antibodies on cell migration  

Microsoft Academic Search

Antiphospholipid syndrome (APS) is characterized by the presence of a heterogenous class of antibodies directed against phospholipids and associated with high occurrence of thrombotic complications. Antiendothelial cell antibodies (AECAs) have been identified in various autoimmune disorders including APS, but their reactivity patterns remain unclear. We used eluted endothelial membrane-bound antibodies (EC eluates) to investigate possible cross-reactivity of AECAs and their

N. Lanir; M. Zilberman; I. Yron; G. Tennenbaum; Y. Shechter; B. Brenner

1998-01-01

192

IBC’s 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics International Conferences and the 2012 Annual Meeting of The Antibody Society  

PubMed Central

The 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences, and the 2012 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, were held December 3–6, 2012 in San Diego, CA. The meeting drew over 800 participants who attended sessions on a wide variety of topics relevant to antibody research and development. As a prelude to the main events, a pre-conference workshop held on December 2, 2012 focused on intellectual property issues that impact antibody engineering. The Antibody Engineering Conference was composed of six sessions held December 3–5, 2012: (1) From Receptor Biology to Therapy; (2) Antibodies in a Complex Environment; (3) Antibody Targeted CNS Therapy: Beyond the Blood Brain Barrier; (4) Deep Sequencing in B Cell Biology and Antibody Libraries; (5) Systems Medicine in the Development of Antibody Therapies/Systematic Validation of Novel Antibody Targets; and (6) Antibody Activity and Animal Models. The Antibody Therapeutics conference comprised four sessions held December 4–5, 2012: (1) Clinical and Preclinical Updates of Antibody-Drug Conjugates; (2) Multifunctional Antibodies and Antibody Combinations: Clinical Focus; (3) Development Status of Immunomodulatory Therapeutic Antibodies; and (4) Modulating the Half-Life of Antibody Therapeutics. The Antibody Society’s special session on applications for recording and sharing data based on GIATE was held on December 5, 2012, and the conferences concluded with two combined sessions on December 5–6, 2012: (1) Development Status of Early Stage Therapeutic Antibodies; and (2) Immunomodulatory Antibodies for Cancer Therapy. PMID:23575266

Klöhn, Peter-Christian; Wuellner, Ulrich; Zizlsperger, Nora; Zhou, Yu; Tavares, Daniel; Berger, Sven; Zettlitz, Kirstin A.; Proetzel, Gabriele; Yong, May; Begent, Richard H.J.; Reichert, Janice M

2013-01-01

193

Mechanisms of Neonatal Mucosal Antibody Protection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Following an abrupt transition at birth from the sterile uterus to an environment with abundant commensal and pathogenic microbes, neonatal mammals are protected by maternal antibodies at mucosal surfaces. We show in mice that different antibody isotypes work in distinct ways to protect the neonatal...

194

8th Annual European Antibody Congress 2012  

PubMed Central

The 8th European Antibody Congress (EAC), organized by Terrapin Ltd., was again held in Geneva, Switzerland, following on the tradition established with the 4th EAC. The new agenda format for 2012 included three parallel tracks on: (1) naked antibodies; (2) antibody drug conjugates (ADCs); and (3) bispecific antibodies and alternative scaffolds. The meeting started and closed with three plenary lectures to give common background and to share the final panel discussion and conclusions. The two day event included case studies and networking for nearly 250 delegates who learned of the latest advances and trends in the global development of antibody-based therapeutics. The monoclonal antibody track was focused on understanding the structure-function relationships, optimization of antibody design and developability, and processes that allow better therapeutic candidates to move through the clinic. Discussions on novel target identification and validation were also included. The ADC track was dedicated to evaluation of the ongoing success of the established ADC formats alongside the rise of the next generation drug-conjugates. The bispecific and alternative scaffold track was focused on taking stock of the multitude of bispecific formats being investigated and gaining insight into recent innovations and advancements. Mechanistic understanding, progression into the clinic and the exploration of multispecifics, redirected T cell killing and alternative scaffolds were extensively discussed. In total, nearly 50 speakers provided updates of programs related to antibody research and development on-going in the academic, government and commercial sectors. PMID:23493119

Beck, Alain; Carter, Paul J.; Gerber, Hans-Peter; Lugovskoy, Alexey A.; Wurch, Thierry; Junutula, Jagath R.; Kontermann, Roland E; Mabry, Robert

2013-01-01

195

Cytolytic Antibodies to Melanocytes in Vitiligo  

Microsoft Academic Search

Patients with vitiligo have been found to have circulating antibodies to pigment cells. To evaluate the functional activity of these antibodies, a highly sensitive europium release assay was used to compare complement-mediated cytolysis of human melanocytes by sera of 56 patients with vitiligo (20 with active disease, 25 with inactive disease, 11 with unidentified disease activity) and 47 control individuals.

Jian Cui; Yuko Arita; Jean-Claude Bystryn

1993-01-01

196

Anti-influenza M2e antibody  

DOEpatents

Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

Bradbury, Andrew M.

2013-04-16

197

Anticardiolipin antibodies: occurrence in Behçet's syndrome  

Microsoft Academic Search

Anticardiolipin antibodies have recently been described in association with arterial and venous thrombosis, and with neurological symptoms, in connective tissue diseases. In a study of 70 patients with Behçet's syndrome 13 patients had these antibodies. Of these 13 patients eight had a history of either retinal vascular pathology, cerebral infarction, or thrombophlebitis. The association of retinal vascular disease and the

R G Hull; E N Harris; A E Gharavi; A Tincani; R A Asherson; G Valesini; A M Denman; G Froude; G R Hughes

1984-01-01

198

7th Annual European Antibody Congress 2011  

PubMed Central

The 7th European Antibody Congress (EAC), organized by Terrapin Ltd., was again held in Geneva, Switzerland, following on the tradition established with the 4th EAC. The 2011 version of the EAC was attended by nearly 250 delegates who learned of the latest advances and trends in the global development of antibody-based therapeutics. The first day focused on advances in understanding structure-function relationships, choosing the best format, glycoengineering biobetter antibodies, improving the efficacy and drugability of mAbs and epitope mapping. On the second day, the discovery of novel targets for mAb therapy, clinical pipeline updates, use of antibody combinations to address resistance, generation and identification of mAbs against new targets and biosimilar mAb development were discussed. Antibody-drug conjugates, domain antibodies and new scaffolds and bispecific antibodies were the topics of the third day. In total, nearly 50 speakers provided updates of programs related to antibody research and development on-going in the academic, government and commercial sectors. PMID:22453093

2012-01-01

199

Anti-influenza M2e antibody  

DOEpatents

Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

Bradbury, Andrew M. (Santa Fe, NM)

2011-12-20

200

Antibody-based therapy of leukaemia.  

PubMed

Over the past decade, monoclonal antibodies have dramatically impacted the treatment of haematological malignancies, as evidenced by the effect of rituximab on the response rate and survival of patients with follicular and diffuse large B cell non-Hodgkin's lymphoma. Currently, only two monoclonal antibodies - the anti-CD33 immunotoxin gemtuzumab ozogamicin and the CD52-directed antibody alemtuzumab - are approved for treatment of relapsed acute myeloid leukaemia in older patients and B cell chronic lymphocytic leukaemia, respectively. Although not approved for such treatment, alemtuzumab is also active against T cell prolymphocytic leukaemia, cutaneous T cell lymphoma and Sézary syndrome, and adult T cell leukaemia and lymphoma. In addition, rituximab has demonstrated activity against B cell chronic lymphocytic and hairy cell leukaemia. Monoclonal antibodies targeting CD4, CD19, CD20, CD22, CD23, CD25, CD45, CD66 and CD122 are now being studied in the clinic for the treatment of leukaemia. Here, we discuss how these new antibodies have been engineered to reduce immunogenicity and improve antibody targeting and binding. Improved interactions with Fc receptors on immune effector cells can enhance destruction of target cells through antibody-dependent cellular cytotoxicity and complement-mediated cell lysis. The antibodies can also be armed with cellular toxins or radionuclides to enhance the destruction of leukaemia cells. PMID:19788782

Morris, John C; Waldmann, Thomas A

2009-01-01

201

Radiohalogenated half-antibodies and maleimide intermediate therefor  

DOEpatents

N-(m-radiohalophenyl) maleimide can be conjugated with a reduced antibody having a mercapto group to provide a radiolabeled half-antibody having immunological specific binding characteristics of whole antibody. No Drawings

Kassis, A.I.; Khawli, L.A.

1991-02-19

202

21 CFR 866.5090 - Antimitochondrial antibody immunological test system.  

... Immunological Test Systems § 866.5090 Antimitochondrial...antibody immunological test system. (a) Identification...antibody immunological test system is a device that consists...antimitochondrial antibodies in human serum. The measurements...produced against the body's own...

2014-04-01

203

21 CFR 866.5090 - Antimitochondrial antibody immunological test system.  

Code of Federal Regulations, 2013 CFR

... Immunological Test Systems § 866.5090 Antimitochondrial...antibody immunological test system. (a) Identification...antibody immunological test system is a device that consists...antimitochondrial antibodies in human serum. The measurements...produced against the body's own...

2013-04-01

204

21 CFR 866.5090 - Antimitochondrial antibody immunological test system.  

Code of Federal Regulations, 2012 CFR

... Immunological Test Systems § 866.5090 Antimitochondrial...antibody immunological test system. (a) Identification...antibody immunological test system is a device that consists...antimitochondrial antibodies in human serum. The measurements...produced against the body's own...

2012-04-01

205

21 CFR 866.5090 - Antimitochondrial antibody immunological test system.  

Code of Federal Regulations, 2010 CFR

... Immunological Test Systems § 866.5090 Antimitochondrial...antibody immunological test system. (a) Identification...antibody immunological test system is a device that consists...antimitochondrial antibodies in human serum. The measurements...produced against the body's own...

2010-04-01

206

21 CFR 866.5090 - Antimitochondrial antibody immunological test system.  

Code of Federal Regulations, 2011 CFR

... Immunological Test Systems § 866.5090 Antimitochondrial...antibody immunological test system. (a) Identification...antibody immunological test system is a device that consists...antimitochondrial antibodies in human serum. The measurements...produced against the body's own...

2011-04-01

207

21 CFR 866.5100 - Antinuclear antibody immunological test system.  

Code of Federal Regulations, 2012 CFR

...antibody immunological test system. 866.5100 Section...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Immunological Test Systems § 866.5100 Antinuclear...antibody immunological test system is a device that consists...antibodies in serum, other body fluids,...

2012-04-01

208

21 CFR 866.5100 - Antinuclear antibody immunological test system.  

Code of Federal Regulations, 2010 CFR

...antibody immunological test system. 866.5100 Section...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Immunological Test Systems § 866.5100 Antinuclear...antibody immunological test system is a device that consists...antibodies in serum, other body fluids,...

2010-04-01

209

21 CFR 866.5100 - Antinuclear antibody immunological test system.  

Code of Federal Regulations, 2011 CFR

...antibody immunological test system. 866.5100 Section...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Immunological Test Systems § 866.5100 Antinuclear...antibody immunological test system is a device that consists...antibodies in serum, other body fluids,...

2011-04-01

210

The Clinical Proteomic Technologies for Cancer | Antibody Scientific Committee  

Cancer.gov

The Antibody Scientific Committee provides scientific insight and guidance to the National Cancer Institute's Antibody Characterization Program. Specifically the members of this committee evaluate request from the external scientific community for development and characterization of antibodies by the program.

211

Principles and application of antibody libraries for infectious diseases.  

PubMed

Antibodies have been used efficiently for the treatment and diagnosis of many diseases. Recombinant antibody technology allows the generation of fully human antibodies. Phage display is the gold standard for the production of human antibodies in vitro. To generate monoclonal antibodies by phage display, the generation of antibody libraries is crucial. Antibody libraries are classified according to the source where the antibody gene sequences were obtained. The most useful library for infectious diseases is the immunized library. Immunized libraries would allow better and selective enrichment of antibodies against disease antigens. The antibodies generated from these libraries can be translated for both diagnostic and therapeutic applications. This review focuses on the generation of immunized antibody libraries and the potential applications of the antibodies derived from these libraries. PMID:25214212

Lim, Bee Nar; Tye, Gee Jun; Choong, Yee Siew; Ong, Eugene Boon Beng; Ismail, Asma; Lim, Theam Soon

2014-12-01

212

Antichlamydial Antibodies, Human Fertility, and Pregnancy Wastage  

PubMed Central

Genital infections with Chlamydia trachomatis (C. trachomatis) continue to be a worldwide epidemic. Immune response to chlamydia is important to both clearance of the disease and disease pathogenesis. Interindividual responses and current chlamydial control programs will have enormous effects on this disease and its control strategies. Humoral immune response to C. trachomatis occurs in humans and persistent antibody levels appear to be most directly correlated with more severe and longstanding disease and with reinfection. There is a close correlation between the presence of antichlamydial antibodies in females and tubal factor infertility; the closest associations have been found for antibodies against chlamydial heat shock proteins. The latter antibodies have also been shown to be useful among infertile patients with prior ectopic pregnancy, and their presence has been correlated with poor IVF outcomes, including early pregnancy loss. We review the existing literature on chlamydial antibody testing in infertile patients and present an algorithm for such testing in the infertile couple. PMID:21949601

Stephens, Amanda J.; Aubuchon, Mira; Schust, Danny J.

2011-01-01

213

Radiolabeled antibodies for therapy of infectious diseases  

PubMed Central

Novel approaches to treatment of infectious diseases are urgently needed. This need has resulted in renewing the interest in antibodies for therapy of infectious diseases. Radioimmunotherapy (RIT) is a cancer treatment modality, which utilizes radiolabeled monoclonal antibodies (mAbs). During the last decade we have translated RIT into the field of experimental fungal, bacterial and HIV infections. In addition, successful proof of principle experiments with radiolabeled pan-antibodies that bind to antigens shared by major pathogenic fungi were performed in vitro. The armamentarium of pan-antibodies would result in reducing the dependence on microorganism-specific antibodies and thus would speed up the development of RIT of infections. We believe that the time is ripe for deploying RIT into the clinic to combat infectious diseases. PMID:25599011

Dadachova, Ekaterina; Casadevall, Arturo

2014-01-01

214

Pigeon breeders' lung lacking detectable antibodies.  

PubMed

Whereas fifteen pigeon fanciers suffering from extrinsic allergic alevolitis from avian dust had high titres of antibodies against pigeon antigens, antibodies were not demonstrable, even by immunofluorescence, in the serum of a symptomatic individual exposed to minimal amounts of avian dust. Following exposure to larger quantities of pigeon dust inhalation challenges, a low titre of antibodies appeared, but disappeared again after avoidance of the allergen. Cell-mediated immunity was elevated in the lymphocyte transformation test and also decreased after avoidance of allergen contact. Therefore, it seems likely that the antibody is not the only mediator of pigeon breeder's lung. Inhalation challenges and T cell-dependent immune reactivity may reveal more avian dust sensitive individuals suffering from fibrosis without the typical history of extrinsic allergic alevolitis and without detectable antibodies. PMID:668104

Sennekamp, J; Niese, D; Stroehmann, I; Rittner, C

1978-05-01

215

Antibodies against gastrointestinal carcinoid tumors in IDDM.  

PubMed

In this study, 92% of patients' serums known to contain antibodies against islet cells, including the Juvenile Diabetes Foundation provisional reference serum, had antibodies reacting with gastrointestinal carcinoid tumors. Twelve percent of the control serums from healthy individuals bound to carcinoid cells, and 2% bound to islet cells. Seventy-five percent of the children with newly diagnosed insulin-dependent diabetes mellitus had carcinoid tumor antibodies, and 83% had islet cell antibodies. These findings suggest that antigenic determinants are shared between endocrine cells of islets of Langerhans and neuroendocrine tumors of the same embryological derivation. Carcinoid tumors may not only provide an alternative source for islet cell antibody assays but also supply material for isolation of antigens possibly involved in the immunopathogenesis of diabetes. PMID:2469610

Miettinen, A; Holthöfer, H; Kontiainen, S; Miettinen, M; Andersson, L C

1989-05-01

216

Viral antibodies in coyotes from California.  

PubMed

Prevalence of antibodies against canine parvovirus (CPV), canine distemper virus (CDV), and canine adenovirus type 1 (CAV) were determined among 152 coyotes (Canis latrans) at the Naval Petroleum Reserves (NPRC; California, USA) from 1985 to 1990. Overall prevalence of antibodies to CPV, CDV, and CAV was 66%, 37%, and 68%, respectively. Prevalence of CPV and CDV varied significantly among years. Antibody prevalence did not differ between sexes for any disease, but did vary significantly among age classes and was lowest for pups (< 1-yr-old). Among pups, antibody prevalence increased with age for all three diseases. Coyotes are a potential source of viral exposure for endangered San Joaquin kit foxes (Vulpes macrotis mutica), but variation in coyote abundance did not appear to influence antibody prevalence among kit foxes. PMID:9577772

Cypher, B L; Scrivner, J H; Hammer, K L; O'Farrell, T P

1998-04-01

217

Antibodies to laminin in American cutaneous leishmaniasis.  

PubMed Central

We found that serum samples from patients with different clinical forms of American cutaneous leishmaniasis (ACL) contained immunoglobulin G and immunoglobulin M antibodies which reacted with laminin but not with various other purified connective tissue components, such as collagen types I, III, IV, and V and fibronectin. Eighty-one percent of ACL patients had high antilaminin antibody levels, with a relationship existing between ACL ulcers and antibody levels. This was not, however, the case with patients having treated and healed ACL ulcers; only 34% of these patients had elevated antilaminin antibodies. Eighty-four percent of chronic Chagas' disease patients were also found to contain antilaminin antibodies that were limited to the immunoglobulin G class, but these were not detected in patients suffering from any of 11 other infectious diseases. PMID:6418660

Avila, J L; Rojas, M; Rieber, M

1984-01-01

218

Antibody epitope mapping using SPOT peptide arrays.  

PubMed

Information at the amino acid level about the epitopes of proteins recognized by antibodies or antibody fragments is important for their use as biological and diagnostic tools, therapeutic molecules, and for understanding molecular recognition events in general. The use of chemically prepared arrays of short peptides has emerged as a powerful tool to identify and characterize antibody epitopes. In this chapter the SPOT synthesis technique is described in detail. In addition, three different types of peptide libraries and their applications are described: protein sequence-derived scans of overlapping peptides (peptide scans) used to locate epitopes within the protein sequence, truncation libraries used to identify the minimal peptide length required for antibody binding, and complete substitutional analyses to identify the key residues important for antibody binding. PMID:19377943

Reineke, Ulrich; Sabat, Robert

2009-01-01

219

Chemically Modified Antibodies as Diagnostic Imaging Agents  

PubMed Central

Summary Notable new applications of antibodies for imaging involve genetically extracting the essential molecular recognition properties of an antibody, and in some cases enhancing them by mutation, before protein expression. The classic paradigm of intravenous administration of a labeled antibody to image not only its target but also its metabolism can be improved on. Protocols in which molecular targeting with an engineered unlabeled protein derived from an antibody, followed by capture of a small probe molecule that provides a signal, are being developed to a high level of utility. This is accompanied by new strategies for probe capture such as irreversible binding, incorporation of engineered enzyme active sites, and antibody-ligand systems that generate a signal only upon binding or uptake. PMID:20952245

Day, Jeffrey J.; Marquez, Bernadette V.; Beck, Heather E.; Aweda, Tolulope A.; Gawande, Prasad D.; Meares, Claude F.

2010-01-01

220

Progress towards recombinant anti-infective antibodies  

PubMed Central

The global market for monoclonal antibody therapeutics reached a total of $11.2 billion in 2004, with an impressive 42% growth rate over the previous five years and is expected to reach ~$34 billion by 2010. Coupled with this growth are stream-lined product development, production scale-up and regulatory approval processes for the highly conserved antibody structure. While only one of the 21 current FDA-approved antibodies, and one of the 38 products in advanced clinical trials target infectious diseases, there is increasing academic, government and commercial interest in this area. Synagis, an antibody neutralizing respiratory syncitial virus (RSV), garnered impressive sales of $1.1 billion in 2006 in spite of its high cost and undocumented effects on viral titres in human patients. The success of anti-RSV passive immunization has motivated the continued development of anti-infectives to treat a number of other infectious diseases, including those mediated by viruses, toxins and bacterial/fungal cells. Concurrently, advances in antibody technology suggest that cocktails of several monoclonal antibodies with unique epitope specificity or single monoclonal antibodies with broad serotype specificity may be the most successful format. Recent patents and patent applications in these areas will be discussed as predictors of future anti-infective therapeutics. PMID:19149692

Pai, Jennifer C.; Sutherland, Jamie N.; Maynard, Jennifer A.

2009-01-01

221

Therapeutic potential of monovalent monoclonal antibodies  

NASA Astrophysics Data System (ADS)

One therapeutic use for monoclonal antibody technology1 is the elimination of categories of unwanted cells by virtue of their distinct cell surface antigens. The efficiency of cell destruction by complement lysis or opsonization depends on a number of factors such as antibody specificity and isotype as well as certain properties of the target antigen2. In some instances cells can escape destruction by redistributing and eventually losing the antigen-antibody complexes from their surface3,4. This process, known as antigenic modulation, generally depends on bivalent antibody binding. Starting from the observation that rabbit antisera can be made more effective at killing tumour cells if they are first rendered univalent by limited proteolysis, we have now prepared a number of monovalent rat monoclonal antibodies to human cell-surface antigens. We find that these antibodies are no longer able to bring about modulation of their target antigens and have an enhanced facility for lysis with human complement. These special properties should greatly increase the therapeutic potential of monoclonal antibodies.

Cobbold, S. P.; Waldmann, H.

1984-03-01

222

Glycosylation profiles of therapeutic antibody pharmaceuticals.  

PubMed

Recombinant antibodies specific for human targets are often used as therapeutics and represent a major class of drug products. Their therapeutic efficacy depends on the formation of antibody complexes resulting in the elimination of a target molecule or the modulation of specific signalling pathways. The physiological effects of antibody therapeutics are known to depend on the structural characteristics of the antibody molecule, specifically on the glycosylation which is the result of posttranslational modifications. Hence, production of therapeutic antibodies with a defined and consistent glycoform profile is needed which still remains a considerable challenge to the biopharmaceutical industry. To provide an insight into the industries capability to control their manufacturing process and to provide antibodies of highest quality, we conducted a market surveillance study and compared major oligosaccharide profiles of a number of monoclonal antibody pharmaceuticals sampled on the Swiss market. Product lot-to-lot variability was found to be generally low, suggesting that a majority of manufacturers have implemented high quality standards in their production processes. However, proportions of G0, G1 and G2 core-fucosylated chains derived from different products varied considerably and showed a bias towards the immature agalactosidated G0 form. Interestingly, differences in glycosylation caused by the production cell type seem to be of less importance compared with process related parameters such as cell growth. PMID:21745568

Wacker, Christoph; Berger, Christoph N; Girard, Philippe; Meier, Roger

2011-11-01

223

Monoclonal anti-A antibody removal by synthetic A antigen immobilized on specific antibody filters.  

PubMed

Removal of blood group anti-A and anti-B antibodies can prevent hyperacute organ rejection in ABO-incompatible transplantation. We are developing an extracorporeal-specific antibody filter (SAF) as an immunoadsorption device for direct removal of ABO blood group antibodies from whole blood, without the need for plasma separation and plasma exchange. A hollow fiber-based small scale SAF (mini-SAF) device was fabricated and synthetic A antigen, Atrisaccharide (Atri) conjugated to activated polyacrylic acid, was immobilized on the fiber lumen surface. Monoclonal antibody anti-A IgM were specifically removed up to 70% of initial antibodies using mini-SAF device. The monoclonal anti-A capture experiments on mini-SAF indicated that antibody removal relative to the initial concentration is independent of inlet concentration in the beginning; however, as the surface starts saturating with bound antibodies, removal becomes dependent on inlet concentration. No significant effect of flow rate on removal rate was observed. The radial diffusion and axial convection-based mathematical model developed for unsteady state antibody removal was in good agreement with the experimental data and showed that the antibody removal rate can be maximized by increasing the antibody-binding capacity of the SAF. PMID:17705231

Gautam, Shalini; Korchagina, Elena Y; Bovin, Nicolai V; Federspiel, William J

2008-03-01

224

Effect of antibody charge and concentration on deposition of antibody to glomerular basement membrane  

SciTech Connect

Fixed anionic sites within the glomerular capillary wall influence the permeation of serum proteins, the localization of various antigens, and the deposition of antibody in the subepithelial space. In anti-GBM nephritis antibody deposition occurs very rapidly to antigenic sites located relatively proximal in the glomerular capillary wall. The authors examined the influence of the glomerular charge barrier on anti-GBM antibody deposition by comparing the rate of deposition of antibodies with cationic and anionic isoelectric points. Purified sheep anti-rat GBM IgG was isolated from acid eluates of kidneys obtained 24 hr after rats were injected with sheep antiserum to rat GBM. Anti-GBM IgG was separated into cationic (pI 6.4-8.5) and anionic (pI 4.2-6.8) fractions, which were radiolabelled with /sup 131/I and /sup 125/I, respectively, shown to have equal antibody contents measured by in vitro binding to normal glomeruli, mixed in equal amounts, and injected in incremental doses to ten rats. At 1 hr the glomerular antibody binding of each fraction was directly related to the blood level (r . 0.95, r . 0.97) and delivery of antibody (r . 0.98, r . 0.98). Glomerular binding of cationic antibody was four times greater than anionic antibody over the entire range of deliveries studied (P less than 0.001). The authors conclude that glomerular deposition of anti-GBM antibody is directly related to blood concentration and delivery of antibody. Furthermore, the deposition of cationic antibodies to GBM antigens was significantly greater than the deposition of anionic antibodies.

Madaio, M.P.; Salant, D.J.; Adler, S.; Darby, C.; Couser, W.G.

1984-10-01

225

Coeliac Disease-Associated Antibodies in Psoriasis  

PubMed Central

Background The possible relationship between psoriasis and coeliac disease (CD) has been attributed to the common pathogenic mechanisms of the two diseases and the presence of antigliadin antibodies in patients has been reported to increase the incidence of CD. Objective The aim of this report was to study CD-associated antibodies serum antigliadin antibody immunoglobulin (Ig)A, IgG, anti-endomysial antibody IgA and anti-transglutaminase antibody IgA and to demonstrate whether there is an increase in the frequency of those markers of CD in patients with psoriasis. Methods Serum antigliadin antibody IgG and IgA, antiendomysial antibody IgA and anti-transglutaminase antibody IgA were studied in 37 (19 males) patients with psoriasis and 50 (23 males) healthy controls. Upper gastrointestinal endoscopy and duodenal biopsies were performed in patients with at least one positive marker. Results Antigliadin IgA was statistically higher in the psoriasis group than in the controls (p<0.05). Serological markers were found positive in 6 patients with psoriasis and 1 person from the control group. Upper gastrointestinal endoscopy was performed in all these persons, with biopsies collected from the duodenum. The diagnosis of CD was reported in only one patient with psoriasis following the pathological examination of the biopsies. Whereas one person of the control group was found to be positive for antigliadin antibody IgA, pathological examination of the duodenal biopsies obtain from this patient were found to be normal. Conclusion Antigliadin IgA prominently increases in patients diagnosed with psoriasis. Patients with psoriasis should be investigated for latent CD and should be followed up. PMID:24003271

Akbulut, Sabiye; Gür, Günes; Topal, Firdevs; Topal, Fatih Esad; Alli, Nuran; Saritas, Ülkü

2013-01-01

226

Antibodies Against Three Forms of Urokinase  

NASA Technical Reports Server (NTRS)

Antibodies that bind to preselected regions of the urokinase molecule have been developed. These antibodies can be used to measure small quantities of each of three molecular forms of urokinase that could be contained in microsamples or conditioned media harvested from cultures of mammalian cells. Previously available antibodies and assay techniques do not yield both clear distinctions among, and measurements of, all three forms. Urokinase is a zymogen that is synthesized in a single-chain form, called ScuPA, which is composed of 411 amino acid residues (see figure). ScuPA has very little enzyme activity, but it can be activated in two ways: (1) by cleavage of the peptide bond lysine 158/isoleucine 159 and the loss of lysine 158 to obtain the high molecular-weight (HMW) form of the enzyme or (2) by cleavage of the bond lysine 135/lysine 136 to obtain the low-molecular-weight (LMW) form of the enzyme. The antibodies in question were produced in mice and rabbits by use of peptides as immunogens. The peptides were selected to obtain antibodies that bind to regions of ScuPA that include the lysine 158/isoleucine 159 and the lysine 135/lysine 136 bonds. The antibodies include monoclonal and polyclonal ones that yield indications as to whether either of these bonds is intact. The polyclonal antibodies include ones that preferentially bind to the HMW or LMW forms of the urokinase molecule. The monoclonal antibodies include ones that discriminate between the ScuPA and the HMW form. A combination of these molecular-specific antibodies will enable simultaneous assays of the ScuPA, HMW, and LMW forms in the same specimen of culture medium.

Morrison, Dennis R.; Atassi, M. Zouhair

2007-01-01

227

The antibody approach of labeling blood cells  

SciTech Connect

Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

Srivastava, S.C.

1991-01-01

228

The antibody approach of labeling blood cells  

SciTech Connect

Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

Srivastava, S.C.

1991-12-31

229

Bispecific antibodies with natural architecture produced by co-culture of bacteria expressing two distinct half-antibodies.  

PubMed

By enabling the simultaneous engagement of two distinct targets, bispecific antibodies broaden the potential utility of antibody-based therapies. However, bispecific-antibody design and production remain challenging, owing to the need to incorporate two distinct heavy and light chain pairs while maintaining natural nonimmunogenic antibody architecture. Here we present a bispecific-antibody production strategy that relies on co-culture of two bacterial strains, each expressing a half-antibody. Using this approach, we produce 28 unique bispecific antibodies. A bispecific antibody against the receptor tyrosine kinases MET and EGFR binds both targets monovalently, inhibits their signaling, and suppresses MET and EGFR-driven cell and tumor growth. Our strategy allows rapid generation of bispecific antibodies from any two existing antibodies and yields milligram to gram quantities of bispecific antibodies sufficient for a wide range of discovery and preclinical applications. PMID:23831709

Spiess, Christoph; Merchant, Mark; Huang, Arthur; Zheng, Zhong; Yang, Nai-Ying; Peng, Jing; Ellerman, Diego; Shatz, Whitney; Reilly, Dorothea; Yansura, Daniel G; Scheer, Justin M

2013-08-01

230

Catumaxomab: a bispecific trifunctional antibody.  

PubMed

The trifunctional bispecific monoclonal antibody catumaxomab has two binding specificities directed at epithelial cell adhesion molecule (EpCAM) and the T-cell antigen CD3. With its Fc-fragment, catumaxomab additionally binds accessory cells such as dendritic cells, macrophages and natural killer cells. The trifunctional approach thus leads to unrestricted but specific killing of epithelial tumor cells by major histocompatibility complex without the need for preactivation or external costimulation. The tumor-associated antigen EpCAM is strongly expressed in carcinomas of various origins including colon, rectum, ovarian, gastric, esophagus, lung, pancreas, breast and head and neck. Expression of EpCAM is often associated with an unfavorable prognosis in patients with breast cancer. Catumaxomab has been approved in Europe for the intraperitoneal treatment of malignant ascites in patients with EpCAM-positive epithelial tumors when standard therapy is not available or is no longer feasible. Basic preclinical and clinical findings with different routes of catumaxomab administration in various indications are summarized and discussed in this review. PMID:19927225

Sebastian, M; Kuemmel, A; Schmidt, M; Schmittel, A

2009-08-01

231

[Therapeutic monoclonal antibodies in oncology].  

PubMed

Advances in bioengineering have lead to the possibility to conduct large scale production of monoclonal antibodies (MoAB) and to reduce progressively the murine component from 30% (chimeric MoAB) to 5% (humanized MoAB) to 0% (human MoAB). Three types of extracellular components are targeted in solid tumours: (1) Growth factors with transmembrane tyrosine kinase receptors either of tumour cells (IGF1) or endothelial cells (Bevacizumab). Bevacizumab has activity additive to that of chemotherapy in advanced colorectal, non squamous lung, ovarian, metastatic breast cancers and glioblastomas; (2) Extracellular domain of those transmembrane receptors: EGFR in colorectal cancer if no activating of KRAS with cetuximab and panitumumab, head and neck carcinomas with radiotherapy, and probably squamous lung cancers. Anti-ERBB2 MoAb are now a constitutive part of therapy of ERBB2 positive breast cancers at any stage; (3) Differentiation cluster regulating relationship ot tumour and stromal cells and in particular immunologic effectors. This is the case of anti-CTLA4 MoAB ipilimumab which activates and amplifies immunological cytotoxic response against melanoma with improved survival. These activities are achieved to the expense of class, target related toxicity conditioned by expression of the target on normal cells and or mechanism of action (immunological toxicity with ipilimumab). Of note a synergistic or additive activity with valid treatment regimens of targeted cancers and now targeted small molecules. PMID:22863361

Bouzid, K; Bedairia, N; Marty, M

2012-08-01

232

Optimising testing for phospholipid antibodies  

PubMed Central

Aim—To compare anticardiolipin (ACL) and anti-ß2 glycoprotein 1 (ß2gp1) enzyme linked immunosorbent assays (ELISAs) in the diagnosis of antiphospholipid syndrome (APS) and to incorporate these results into a meta-analysis of published data. Method—Three representative commercial ACL ELISAs and an in house ß2gp1 assay were optimised and then assessed on 124 sera from normal donors, patients with infection, or patients with APS. A Medline search was screened for papers meeting defined criteria to conduct a meta-analysis. The performance of the assays used in this study was included. Results—A non-quantitative ACL assay performed at least as well as the anti-ß2gp1 assay in the diagnosis of APS. Meta-analysis confirmed that neither assay is perfect, although the anti-ß2gp1 assay had a higher specificity and lower sensitivity than the ACL assay. Conclusions—The pooled data suggest that the ACL assay is used to investigate thrombosis without overt underlying pathology and that the improved specificity of the anti-ß2gp1 assay is exploited where infection, connective tissue disease, or atheroma are present. Key Words: antiphospholipid syndrome • anticardiolipin antibodies • anti-ß2 glycoprotein 1 • sensitivity PMID:11533076

Helbert, M; Bodger, S; Cavenagh, J; D'Cruz, D; Thomas, J; MacCallum, P

2001-01-01

233

Antibodies to watch in 2010  

PubMed Central

Monoclonal antibodies (mAbs) are a burgeoning class of therapeutics, with more than 25 approved in countries worldwide. Novel molecules are entering clinical study at a rate of nearly 40 per year, and the commercial pipeline includes approximately 240 mAb therapeutics in clinical studies that have not yet progressed to regulatory approval or been approved. Of particular interest are the 26 mAbs that are currently at Phase 3, when safety and efficacy data critical to approval is established. Phase 3 study lengths are typically two to four years, so results for some studies might be announced in 2010, but data from others might not be presented until 2014. This overview of the 26 candidates provides a brief description of the background and the on-going Phase 3 studies of each mAb. Additional mAbs that have progressed to regulatory review or been approved may also be in Phase 3 studies, but these, as well as Fc fusion proteins, have been excluded. Due to the large body of primary literature about the 26 candidates, only selected references are given, with a focus on recent publications and articles that were relevant to Phase 3 studies. Current as of October 2009, the results presented here will serve as a baseline against which future progress can be measured. PMID:20065640

2010-01-01

234

Non-fucosylated therapeutic antibodies: the next generation of therapeutic antibodies  

PubMed Central

Therapeutic antibody IgG1 has two N-linked oligosaccharide chains bound to the Fc region. The oligosaccharides are of the complex biantennary type, composed of a trimannosyl core structure with the presence or absence of core fucose, bisecting N-acetylglucosamine (GlcNAc), galactose, and terminal sialic acid, which gives rise to structural heterogeneity. Both human serum IgG and therapeutic antibodies are well known to be heavily fucosylated. Recently, antibody-dependent cellular cytotoxicity (ADCC), a lytic attack on antibody-targeted cells, has been found to be one of the critical effector functions responsible for the clinical efficacy of therapeutic antibodies such as anti-CD20 IgG1 rituximab (Rituxan®) and anti-Her2/neu IgG1 trastuzumab (Herceptin®). ADCC is triggered upon the binding of lymphocyte receptors (Fc?Rs) to the antibody Fc region. The activity is dependent on the amount of fucose attached to the innermost GlcNAc of N-linked Fc oligosaccharide via an ?-1,6-linkage, and is dramatically enhanced by a reduction in fucose. Non-fucosylated therapeutic antibodies show more potent efficacy than their fucosylated counterparts both in vitro and in vivo, and are not likely to be immunogenic because their carbohydrate structures are a normal component of natural human serum IgG. Thus, the application of non-fucosylated antibodies is expected to be a powerful and elegant approach to the design of the next generation therapeutic antibodies with improved efficacy. In this review, we discuss the importance of the oligosaccharides attached to the Fc region of therapeutic antibodies, especially regarding the inhibitory effect of fucosylated therapeutic antibodies on the efficacy of non-fucosylated counterparts in one medical agent. The impact of completely non-fucosylated therapeutic antibodies on therapeutic fields will be also discussed. PMID:19003000

Mori, Katsuhiro; Iida, Shigeru; Yamane-Ohnuki, Naoko; Kanda, Yutaka; Kuni-Kamochi, Reiko; Nakano, Ryosuke; Imai-Nishiya, Harue; Okazaki, Akira; Shinkawa, Toyohide; Natsume, Akihito; Niwa, Rinpei; Shitara, Kenya

2007-01-01

235

Protocol for the selection of single-domain antibody fragments by third generation intracellular antibody capture  

Microsoft Academic Search

Single-domain intracellular antibodies are antibody variable segments that bind to specific target proteins inside cells. These antigen-binding variable regions can interfere with protein function or perturb protein–protein interactions and can be used as tools for research, especially functional genomics and proteomics and interfering with the protein interactome. This protocol (Intracellular Antibody Capture, IAC3) describes the isolation of functional variable heavy

Tomoyuki Tanaka; Terence H Rabbitts

2009-01-01

236

Cost modeling for monoclonal antibody manufacturing  

E-print Network

The Novartis BioPharmOps division is responsible for manufacturing large molecule products, including monoclonal antibodies, for late stage clinical trials and commercial sales. The BioPharmOps site in Huningue, France is ...

Simpson, Christina M. (Christina Margaret)

2011-01-01

237

[Use of antibodies for colorectal cancer chemotherapy].  

PubMed

There are several molecular target therapeutic drugs for colorectal cancer which are used in daily medical practice in Japan. One is bevacizumab which is anti-VEGF antibody, and another is cetuximab and panitumumab which are anti-EGFR antibodies. However, there is not a clear conclusion which drugs should be used in each therapeutic line, and many studies are in progress. The results of the direct competitive examination of anti-VEGF antibody and anti-EGFR antibodies have been reported recently. These drugs are under consideration to differentiate the use not only from the characteristic of the drugs, but also from the pathological condition of the tumor. In this report, we will show the latest findings and the use of each drugs. PMID:24597358

Kanemitsu, Kiyonori; Kakeji, Yoshihiro

2014-01-01

238

Other Autonomic Neuropathies Associated with Ganglionic Antibody  

PubMed Central

The acetylcholine receptor ganglionic (G-AchR) antibody is a very specific serologic test for autoimmune autonomic ganglionopathy. The spectrum of autoimmune (or presumed to be autoimmune) autonomic disorders, however, is quite broad and positivity to this antibody has been reported in a variety of other conditions, albeit infrequent and with low titer. This review describes the autonomic neuropathies most frequently encountered in clinical practice in which an autoimmune etiology is suspected. They include a chronic form (pure autonomic failure) and limited autonomic neuropathies with predominant involvement of one neurotransmitter type (i.e., cholinergic vs. adrenergic) or one system (such as the gastrointestinal system) or a distal small fiber dysfunction. In each of these conditions, occasional positivity to the G-AchR antibody has been found, but the pathogenetic significance of such finding is still uncertain. Other antigens and antibodies yet to be identified are more likely to be responsible in these disorders. PMID:19058765

Sandroni, Paola; Low, Phillip A.

2009-01-01

239

Other autonomic neuropathies associated with ganglionic antibody.  

PubMed

The acetylcholine receptor ganglionic (G-AchR) antibody is a very specific serologic test for autoimmune autonomic ganglionopathy. The spectrum of autoimmune (or presumed to be autoimmune) autonomic disorders, however, is quite broad and positivity to this antibody has been reported in a variety of other conditions, albeit infrequent and with low titer. This review describes the autonomic neuropathies most frequently encountered in clinical practice in which an autoimmune etiology is suspected. They include a chronic form (pure autonomic failure) and limited autonomic neuropathies with predominant involvement of one neurotransmitter type (i.e., cholinergic vs. adrenergic) or one system (such as the gastrointestinal system) or a distal small fiber dysfunction. In each of these conditions, occasional positivity to the G-AchR antibody has been found, but the pathogenetic significance of such finding is still uncertain. Other antigens and antibodies yet to be identified are more likely to be responsible in these disorders. PMID:19058765

Sandroni, Paola; Low, Phillip A

2009-03-12

240

Imaging and dosimetry determinations using radiolabeled antibodies.  

PubMed

Numerous studies using radiolabeled antibodies for imaging and therapy of lymphoma have been reported (Table 4). The targeting of lymphoma associated antigens with MoAb appears to be more favorable than the targeting of antigens on epithelial tumor. Antigen abundance may not be the overriding factor in this favorable targeting, since the number of antigenic sites per cell are often in the same range or lower than those targeted in epithelial tumors. This improved targeting is likely related to the greater access of antibody to the target antigen in lymph nodes, bone marrow, circulation, and other sites. With certain antibodies, trafficking of the cells targeted with the radiolabeled antibody may also result in favorable localization [19]. While the most frequently used isotope for imaging and therapy has been 131I, certain limitations have been observed, including its high-energy gamma rays and resulting lower resolution, and the frequent occurrence of dehalogenation [21,25,98]. Many of the antigens expressed by lymphomas undergo antigenic modulation. Antigens that undergo modulation may be targeted successfully, but once modulation occurs the antibody is broken down and the iodine is rapidly excreted from the cells. While this rapid release from normal organs is an advantage, it is an undesirable event at the tumor site. In contrast to the case of 131I MoAb, modulation may be an advantage for targeting with 111In labeled antibodies, since the radioactive metals are retained for longer periods at the tumor sites; even if the antibody is broken down, the 111In is not easily excreted from the cells [52]. Among the most consistent and favorable targeting observed to date is that seen with 111In T101 in CTCL. These studies have shown concentration of 111In in tumor of 10-100 times that seen in other tumor systems using iodinated antibodies. Unfortunately no studies have followed this lead and performed the necessary comparisons between 111In and 131I MoAb to determine if this is a consistent finding. The use of 99mTc labeled MoAb for imaging lymphomas is in its infancy, although preliminary reports appear promising [71]. While in epithelial tumors preferential tumor targeting may take more than 48 hours in lymphomas, targeting is usually seen within the first 24 hours, which is within the window of imaging time for 99mTc. Therefore, further evaluation of 99mTc antibodies should be performed. Determination of the optimum dose of antibody for imaging has been attempted. Studies using various anti-lymphoma directed antibodies have shown widely varying biodistribution and variable dose-response curves.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8105853

Carrasquillo, J

1993-01-01

241

Mechanisms in removal of tumor by antibody  

Microsoft Academic Search

We report two preliminary trials of antibody treatment of B-cell lymphoma. Advanced lymphoma was treated with chimeric FabFc2, in which mouse Fab'? is linked to two human Fc?1 fragments so as to recruit natural effectors to tumor targets. Terminal\\u000a lymphoma was treated with bispecific antibody (BsAb) which recruits the ribosome-inactivating protein saporin. These different\\u000a mechanisms led to interesting differences in

G. T. Stevenson; A. J. Bell; T. R. J. Evans; R. R. French; M. J. Glennie; T. J. Hamblin; K. S. Kan; G. M. Mead

1994-01-01

242

Production of Native Bispecific Antibodies in Rabbits  

Microsoft Academic Search

BackgroundA natural bispecific antibody, which can be produced by exchanging Fab arms of two IgG4 molecules, was first described in allergic patients receiving therapeutic injections with two distinct allergens. However, no information has been published on the production of natural bispecific antibody in animals. Even more important, establishment of an animal model is a useful approach to investigate and characterize

Wei Wang; Ruihuan Xu; Jinming Li; Vladimir Brusic

2010-01-01

243

Single domain camel antibodies: current status  

Microsoft Academic Search

The antigen-binding capacity of the paired variable domains of an antibody is well established. The observation that the isolated heavy chains of anti-hapten antibodies retain some antigen-binding capacity in the absence of light chains led to attempts to obtain an even smaller antigen-binding unit in a VH format. Unfortunately, the poor solubility, the reduced affinity for the antigen and the

Serge Muyldermans

2001-01-01

244

454 antibody sequencing - error characterization and correction  

PubMed Central

Background 454 sequencing is currently the method of choice for sequencing of antibody repertoires and libraries containing large numbers (106 to 1012) of different molecules with similar frameworks and variable regions which poses significant challenges for identifying sequencing errors. Identification and correction of sequencing errors in such mixtures is especially important for the exploration of complex maturation pathways and identification of putative germline predecessors of highly somatically mutated antibodies. To quantify and correct errors incorporated in 454 antibody sequencing, we sequenced six antibodies at different known concentrations twice over and compared them with the corresponding known sequences as determined by standard Sanger sequencing. Results We found that 454 antibody sequencing could lead to approximately 20% incorrect reads due to insertions that were mostly found at shorter homopolymer regions of 2-3 nucleotide length, and less so by insertions, deletions and other variants at random sites. Correction of errors might reduce this population of erroneous reads down to 5-10%. However, there are a certain number of errors accounting for 4-8% of the total reads that could not be corrected unless several repeated sequencing is performed, although this may not be possible for large diverse libraries and repertoires including complete sets of antibodies (antibodyomes). Conclusions The experimental test procedure carried out for assessing 454 antibody sequencing errors reveals high (up to 20%) incorrect reads; the errors can be reduced down to 5-10% but not less which suggests the use of caution to avoid false discovery of antibody variants and diversity. PMID:21992227

2011-01-01

245

Other autonomic neuropathies associated with ganglionic antibody  

Microsoft Academic Search

The acetylcholine receptor ganglionic (G-AchR) antibody is a very specific serologic test for autoimmune autonomic ganglionopathy. The spectrum of autoimmune (or presumed to be autoimmune) autonomic disorders, however, is quite broad and positivity to this antibody has been reported in a variety of other conditions, albeit infrequent and with low titer.This review describes the autonomic neuropathies most frequently encountered in

Paola Sandroni; Phillip A. Low

2009-01-01

246

Avian Diagnostic and Therapeutic Antibodies to Viral Emerging Pathogens  

SciTech Connect

During the current period the following key objectives were achieved: demonstration of high titer antibody production by geese following immunization with inactived H1N1 virus; completion of the epitope mapping of West Nile Virus-specific goose antibodies and initiation of epitope mapping of H1N1 flu-specific goose antibodies; advancement in scalable purification of goose antibodies.

David Bradley

2011-03-31

247

Antibody Responses during Hepatitis B Viral Infection  

PubMed Central

Hepatitis B is a DNA virus that infects liver cells and can cause both acute and chronic disease. It is believed that both viral and host factors are responsible for determining whether the infection is cleared or becomes chronic. Here we investigate the mechanism of protection by developing a mathematical model of the antibody response following hepatitis B virus (HBV) infection. We fitted the model to data from seven infected adults identified during acute infection and determined the ability of the virus to escape neutralization through overproduction of non-infectious subviral particles, which have HBs proteins on their surface, but do not contain nucleocapsid protein and viral nucleic acids. We showed that viral clearance can be achieved for high anti-HBV antibody levels, as in vaccinated individuals, when: (1) the rate of synthesis of hepatitis B subviral particles is slow; (2) the rate of synthesis of hepatitis B subviral particles is high but either anti-HBV antibody production is fast, the antibody affinity is high, or the levels of pre-existent HBV-specific antibody at the time of infection are high, as could be attained by vaccination. We further showed that viral clearance can be achieved for low equilibrium anti-HBV antibody levels, as in unvaccinated individuals, when a strong cellular immune response controls early infection. PMID:25078553

Ciupe, Stanca M.; Ribeiro, Ruy M.; Perelson, Alan S.

2014-01-01

248

Working towards a consensus for antibody validation  

PubMed Central

Commercial research antibodies are the most commonly used product in the life science tools market, and their applications represent a significant investment of time and resources for researchers. Frequently however, the quality of antibodies does not meet the expectations of consumers, causing loss of valuable time and money. This can delay research efforts and scientific discovery, or even lead to false, irreproducible results to be published in the scientific literature. This raises the question of whether there should be universal standards for validating antibodies.   During the 1 st International Antibody Validation Forum, hosted by St John’s Laboratory Ltd on October 15 th 2014 at Queen Mary University of London, scientists from academia and industry presented data highlighting quality issues arising from lack of antibody validation. While the forum identified significant current problems in the antibody market, it also discussed future opportunities for improved quality and transparency by encouraging data disclosure and data sharing. This article highlights the key issues and conclusions reached at the forum. PMID:25580232

Reiss, Peter D.; Min, Danxi; Leung, Mei Y.

2014-01-01

249

Structural biology of moonlighting: lessons from antibodies.  

PubMed

Protein moonlighting is the property of a number of proteins to have more than one function. However, the definition of moonlighting is somewhat imprecise with different interpretations of the phenomenon. True moonlighting occurs when an individual evolutionary protein domain has one well-accepted role and a secondary unrelated function. The 'function' of a protein domain can be defined at different levels. For example, although the function of an antibody variable fragment (Fv) could be described as 'binding', a more detailed definition would also specify the molecule to which the Fv region binds. Using this detailed definition, antibodies as a family are consummate moonlighters. However, individual antibodies do not moonlight; the multiple functions they exhibit (first binding a molecule and second triggering the immune response) are encoded in different domains and, in any case, are related in the sense that they are a part of what an antibody needs to do. Nonetheless, antibodies provide interesting lessons on the ability of proteins to evolve binding functions. Remarkably similar antibody sequences can bind completely different antigens, suggesting that evolving the ability to bind a protein can result from very subtle sequence changes. PMID:25399593

Martin, Andrew C R

2014-12-01

250

Cytomegalovirus antibody production in renal transplant patients  

PubMed Central

Sera were examined from 50 patients on the renal transplant unit, Cambridge, for antibody against cytomegalovirus by complement fixation and by immunofluorescence for IgG and IgM antibodies. The incidence of antibody on admission was 84% with a possible further 8% so that nearly all had been infected at some time by CMV. 43 (86%) patients showed evidence of active infection after admission, 39 by serology and four only from the examination of post-mortem material. Twenty-one patients produced IgM antibody and production was prolonged for years in patients that survived. Antibody production was related both to transplantation and admission to hospital. The evidence indicated that primary CMV infections were rare, that IgM antibody production was the result of active infection and that this could be attributed to reactivation without the need to invoke re-infection as the source although this type of patient is both susceptible and exposed to re-infection. PMID:4332511

Nagington, J.

1971-01-01

251

Allosteric antibody inhibition of human hepsin protease.  

PubMed

Hepsin is a type II transmembrane serine protease that is expressed in several human tissues. Overexpression of hepsin has been found to correlate with tumour progression and metastasis, which is so far best studied for prostate cancer, where more than 90% of such tumours show this characteristic. To enable improved future patient treatment, we have developed a monoclonal humanized antibody that selectively inhibits human hepsin and does not inhibit other related proteases. We found that our antibody, hH35, potently inhibits hepsin enzymatic activity at nanomolar concentrations. Kinetic characterization revealed non-linear, slow, tight-binding inhibition. This correlates with the crystal structure we obtained for the human hepsin-hH35 antibody Fab fragment complex, which showed that the antibody binds hepsin around ?3-helix, located far from the active centre. The unique allosteric mode of inhibition of hH35 is distinct from the recently described HGFA (hepatocyte growth factor activator) allosteric antibody inhibition. We further explain how a small change in the antibody design induces dramatic structural rearrangements in the hepsin antigen upon binding, leading to complete enzyme inactivation. PMID:22132769

Koschubs, Tobias; Dengl, Stefan; Dürr, Harald; Kaluza, Klaus; Georges, Guy; Hartl, Christiane; Jennewein, Stefan; Lanzendörfer, Martin; Auer, Johannes; Stern, Alvin; Huang, Kuo-Sen; Packman, Kathryn; Gubler, Ueli; Kostrewa, Dirk; Ries, Stefan; Hansen, Silke; Kohnert, Ulrich; Cramer, Patrick; Mundigl, Olaf

2012-03-15

252

Fetal arthrogryposis and maternal serum antibodies.  

PubMed

Arthrogryposis multiplex congenital (AMC) describes multiple joint contractures resulting from lack of movement in utero. Antibodies directed at the fetal isoform of the muscle acetylcholine receptor (AChR) have been reported in a small number of asymptomatic mothers of AMC babies. We examined sera from 179 mothers of AMC babies and 20 parous and non-parous controls to look for antibodies to AChR or undefined muscle or neuronal proteins. We found positive AChR antibodies in only three sera (1.5%) from asymptomatic AMC mothers. However, there was reactivity with muscle or with neuronal antigens in 33% of the sera, and reactivity to undefined neuronal antigens was more common in sera from mothers of AMC babies with CNS involvement (p=0.001) than those without. The offspring of mothers with AChR antibodies may benefit from treatment during pregnancy. Other maternal antibodies require further study, but these observations add to the emerging literature on maternal antibodies associated with developmental intrauterine disorders. PMID:16919948

Dalton, Paola; Clover, Linda; Wallerstein, Robert; Stewart, Helen; Genzel-Boroviczeny, Orsolya; Dean, Andrew; Vincent, Angela

2006-08-01

253

Antibody-mediated resistance against plant pathogens.  

PubMed

Plant diseases have a significant impact on the yield and quality of crops. Many strategies have been developed to combat plant diseases, including the transfer of resistance genes to crops by conventional breeding. However, resistance genes can only be introgressed from sexually-compatible species, so breeders need alternative measures to introduce resistance traits from more distant sources. In this context, genetic engineering provides an opportunity to exploit diverse and novel forms of resistance, e.g. the use of recombinant antibodies targeting plant pathogens. Native antibodies, as a part of the vertebrate adaptive immune system, can bind to foreign antigens and eliminate them from the body. The ectopic expression of antibodies in plants can also interfere with pathogen activity to confer disease resistance. With sufficient knowledge of the pathogen life cycle, it is possible to counter any disease by designing expression constructs so that pathogen-specific antibodies accumulate at high levels in appropriate sub-cellular compartments. Although first developed to tackle plant viruses and still used predominantly for this purpose, antibodies have been targeted against a diverse range of pathogens as well as proteins involved in plant-pathogen interactions. Here we comprehensively review the development and implementation of antibody-mediated disease resistance in plants. PMID:21872654

Safarnejad, Mohammad Reza; Jouzani, Gholamreza Salehi; Tabatabaei, Meisam; Tabatabaie, Meisam; Twyman, Richard M; Schillberg, Stefan

2011-01-01

254

Fourth World Antibody-Drug Conjugate Summit  

PubMed Central

The 4th World Antibody Drug Conjugate (WADC) Summit, organized by Hanson Wade was held on February 29?March 1, 2012 in Frankfurt, Germany, which was also the location for the Antibody Drug Conjugate Summit Europe held in February 2011. During the one year between these meetings, antibody drug conjugates (ADCs) have confirmed their technological maturity and their clinical efficacy in oncology. Brentuximab vedotin (ADCETRISTM) gained approval by the US Food and Drug Administration in August 2011 and trastuzumab emtansine (T-DM1) confirmed impressive clinical efficacy responses in a large cohort of breast cancer patients. During the 4th WADC meeting, antibody-maytansinoid conjugates were showcased by representatives of ImmunoGen (T-DM1, SAR3419, lorvotuzumab mertansine/IMGN801, IMGN529 and IMG853) and Biotest (BT-062). Data on antibody-auristatin conjugates were presented by scientists and clinicians from Seattle Genetics and Takeda (brentuximab vedotin), Pfizer (5T4-MMAF), Agensys/Astella (AGS-16M8F), Progenics (PSMA-ADC) and Genmab (anti-TF ADCs). Alternative payloads such as calicheamicins and duocarmycin used for preparation of ADCs were discussed by Pfizer and Synthon representatives, respectively. In addition, emerging technologies, including site-directed conjugation (Ambrx), a protein toxin as payload (Viventia), hapten-binding bispecific antibodies (Roche), and use of light activated drugs (Photobiotics), were also presented. Last but not least, progresses in solving Chemistry Manufacturing and Control, and pharmacokinetic issues were addressed by scientists from Genentech, Pfizer, Novartis and Pierre Fabre. PMID:22909934

Beck, Alain; Lambert, John; Sun, Michael; Lin, Kedan

2012-01-01

255

STUDIES ON ANTIGEN-ANTIBODY COMPLEXES  

PubMed Central

Solid phase immunoadsorbents were prepared by coupling antigens to agarose. With this technique specific antibodies were easily isolated in large amounts. The ?G-globulin class of antibodies isolated in this manner were not denatured as judged by their normal biological half-life in rabbits. Soluble immune complexes at fivefold antigen excess were prepared from isolated specific antibodies and HSA, human ?-chains, human ?G-globulins, and a Waldenström's macroglobulin as antigens. In all these preparations a characteristic immune complex was encountered that represented the smallest stable antigen-antibody union. In the HSA-anti-HSA system they were found to be AgAb2 complexes, and Ag2Ab complexes in the ?G-anti-?G system. These stable complexes fixed complement ineffectively. Also, a spectrum of larger complexes was present in each system, and these complexes fixed complement effectively. With intact antibodies the disappearance curves of immune complexes from the circulation were composed of three exponential components. The immune complexes larger than AgAb2 were quickly removed from the circulation with half-lives of 0.09–0.37 hr. Their clearance was not dependent on complement components, in that depletion of complement by cobra venom factor and aggregated ?G-globulin did not alter the pattern of their removal from the circulation. However, when the interchain disulfide bonds of antibodies were reduced and alkylated, the removal of the ?-anti-?, HSA-anti-HSA, and ?G-anti-?G complexes was altered. In these experiments the disappearance curves were composed of two exponential components and the rapid removal of the greater than AgAb2 complexes did not occur. The immune complexes prepared from reduced and alkylated antibodies fixed complement ineffectively. The presented data indicate that the rapid removal of circulating immune complexes, containing ?G-globulin molecules as antibodies, depends primarily on the number of antibodies involved. Furthermore, complement fixation is not involved in the rapid removal of such complexes. Nevertheless, the rapid removal of immune complexes and their ability to fix complement have similarities for optimal function in that both processes require intact interchain disulfide bonds of antibodies and complexes that exceed the AgAb2 combination. PMID:5547056

Mannik, Mart; Arend, William P.; Hall, Anthony P.; Gilliland, Bruce C.

1971-01-01

256

The significance of anti-streptokinase antibodies.  

PubMed Central

Antibodies to streptokinase (SK) are widespread in the population, but reports of their effect on the action of SK are conflicting. Specific anti-SK IgG was purified from the sera of 10 patients, five with low titres of anti-SK IgG and five with high titres. The effect of increasing specific anti-SK IgG antibodies on the action of SK was evaluated in vitro using a fluorimetric assay for plasmin and by a fibrin plate lysis assay. The inhibition of SK by whole plasma from a further group of patients was also assessed by the fibrin plate assay. There was a positive correlation between the serum antibody concentration and the quantity of specific anti-SK eluted (r = 0.797; P < 0.005). The addition of specific anti-SK IgG caused a dose-related decrease in SK activity (fluorimetric assay r = -0.93; P = 0.02; fibrin plate assay r = -0.98; P < 0.001). The addition of patient plasma to the fibrin plate assay also resulted in decreased lysis, which was dependent upon antibody titre (r = -0.95; P < 0.0001). Significant in vitro reduction of the activity of SK by specific antibody was demonstrated, and this was similar with plasma containing comparable amounts of antibody. The findings suggest that treatment with SK would be unlikely to induce an effective thrombolytic state when antibody titres are high (such as those seen within 2 years of an initial dose of SK). PMID:8004811

Lynch, M; Pentecost, B L; Littler, W A; Stockley, R A

1994-01-01

257

Neutralization of HIV by Milk Expressed Antibody  

PubMed Central

Background In some areas of the world mother-to-child transmission of HIV remains a significant problem in part due to widespread breastfeeding which is essential due to scarce supply of a safe replacement, protection conferred by breast milk against many enteric illnesses, and cultural norms. We propose that sustained, adequate levels of protective antibodies in breast milk will prevent transmission of HIV. Methods The HIV neutralizing human monoclonal antibody b12 (IgG1) has been expressed as an IgA2 in CHO cells and shown to retain full immunoreactivity and neutralizing activity as the parental IgG1. The expression plasmids containing the b12 heavy and light chains were also used to construct milk specific expression vectors using the GTC goat ?-casein expression vector to direct expression of linked genes to the mammary gland with subsequent secretion into the milk. Female transgenic mice were generated and following parturition, their milk was tested for antibody immunoreactivity with gp120 and neutralization of HIV. Results When compared to CHO derived b12 IgA2 (or IgG1), immunoreactivity was retained. When tested for neutralization, milk derived b12 IgA2 was at least comparable to CHO derived antibody and in some cases superior to CHO derived antibody. Furthermore, milk that expressed b12 IgA2 was significantly more effective at mediating antibody dependent cell killing. Conclusions These results suggest it is possible to achieve functional HIV-specific mAb in the milk of transgenic mice and further investigations are warranted to explore ways for inducing this type of antibody response in the breast milk of HIV infected women. PMID:23269241

Yu, Xiaocong; Pollock, Daniel; Duval, Mark; Lewis, Christopher; Joseph, Kristin; Meade, Harry; Cavacini, Lisa

2012-01-01

258

The antibody mining toolbox: an open source tool for the rapid analysis of antibody repertoires.  

PubMed

In vitro selection has been an essential tool in the development of recombinant antibodies against various antigen targets. Deep sequencing has recently been gaining ground as an alternative and valuable method to analyze such antibody selections. The analysis provides a novel and extremely detailed view of selected antibody populations, and allows the identification of specific antibodies using only sequencing data, potentially eliminating the need for expensive and laborious low-throughput screening methods such as enzyme-linked immunosorbant assay. The high cost and the need for bioinformatics experts and powerful computer clusters, however, have limited the general use of deep sequencing in antibody selections. Here, we describe the AbMining ToolBox, an open source software package for the straightforward analysis of antibody libraries sequenced by the three main next generation sequencing platforms (454, Ion Torrent, MiSeq). The ToolBox is able to identify heavy chain CDR3s as effectively as more computationally intense software, and can be easily adapted to analyze other portions of antibody variable genes, as well as the selection outputs of libraries based on different scaffolds. The software runs on all common operating systems (Microsoft Windows, Mac OS X, Linux), on standard personal computers, and sequence analysis of 1-2 million reads can be accomplished in 10-15 min, a fraction of the time of competing software. Use of the ToolBox will allow the average researcher to incorporate deep sequence analysis into routine selections from antibody display libraries. PMID:24423623

D'Angelo, Sara; Glanville, Jacob; Ferrara, Fortunato; Naranjo, Leslie; Gleasner, Cheryl D; Shen, Xiaohong; Bradbury, Andrew R M; Kiss, Csaba

2014-01-01

259

Detection of antiphospholipid antibodies by flow cytometry: rapid detection of antibody isotype and phospholipid specificity.  

PubMed

Laboratory diagnosis of antiphospholipid antibodies is important in patients with clinical features of the antiphospholipid syndrome, such as thrombosis and fetal loss. We have developed a novel method for the detection of antiphospholipid antibodies using flow cytometry. Anionic phospholipids cardiolipin, phosphatidylserine and phosphatidylinositol are coated onto polystyrene beads of different sizes, allowing detection and semiquantitation of their respective phospholipid antibody isotypes. The results of the flow cytometric method closely correlate those of the standardised anticardiolipin enzyme-linked immunosorbent assay (ELISA), but the method is quicker and is versatile in its ability to detect IgG, IgM and IgA antibody isotypes at the same time. The method promises to be useful in evaluating the significance of phospholipid specificity and antibody isotypes in patients with the antiphospholipid syndrome. PMID:7509510

Stewart, M W; Etches, W S; Russell, A S; Percy, J S; Johnston, C A; Chew, C K; Gordon, P A

1993-10-18

260

Single-domain antibodies and their utility.  

PubMed

Engineered monoclonal antibody fragments have gained market attention due to their versatility and tailor-made potential and are now considered to be an important part of future immunobiotherapeutics. Single-domain antibodies (sdAbs), also known as nanobodies, are derived from VHHs [variable domains (V) of heavy-chain-only antibodies (HCAb)] of camelid heavy-chain antibodies. These nature-made sdAbs are well suited for various applications due to their favorable characteristics such as small size, ease of genetic manipulation, high affinity and solubility, overall stability, resistance to harsh conditions (e.g., low pH, high temperature), and low immunogenicity. Most importantly, sdAbs have the feature of penetrating into cavities and recognizing hidden epitopes normally inaccessible to conventional antibodies, mainly due to their protruding CDR3/H3 loops. In this unit, we will present and discuss comprehensive and step-by-step protocols routinely practiced in our laboratory for isolating sdAbs from immunized llamas (or other members of the Camelidae family) against target antigens using phage-display technology. Expression, purification, and characterization of the isolated sdAbs will then be described, followed by presentation of several examples of applications of sdAbs previously characterized in our laboratory and elsewhere. PMID:24510545

Baral, Toya Nath; MacKenzie, Roger; Arbabi Ghahroudi, Mehdi

2013-01-01

261

Monoclonal antibody expression in mammalian cells.  

PubMed

In the past two decades, the production levels for monoclonal antibodies in mammalian expression systems have improved dramatically. Single cell productivity for monoclonal antibodies has increased 20-50 fold due to the improvements in expression hosts, expression vectors, cell culture media, and production processes. However, most of these improvements are proprietary to large pharmaceutical/biotech companies and involve large steel-tank bioreactors. Therefore, these processes are difficult for small companies and academic labs to reproduce. Transient expression in mammalian cells has recently been used very widely for monoclonal antibody expression. Cell line and expression vector engineering increased expression levels to several hundred milligrams per liter. The availability of highly effective transfection reagents and disposable bioreactors make the transient expression process an efficient and cost-effective way to make recombinant antibodies in large quantity. Here, we describe the protocols for small- to mid-scale transient expression of monoclonal antibodies in shake-flasks and for large-scale production in WAVE bioreactors. PMID:22907362

Zhang, Richard Yi; Shen, Wenyan David

2012-01-01

262

Single Domain Intracellular Antibodies from Diverse Libraries  

PubMed Central

Interfering intracellular antibodies are valuable for biological studies as drug surrogates and as potential macromolecular drugs per se. Their application is still limited because of the difficulty of acquisition of functional intracellular antibodies. We describe the use of the new intracellular antibody capture procedure (IAC3) to facilitate direct isolation of functional single domain antibody fragments using four independent target molecules (LMO2, TP53, CRAF1, and Hoxa9) from a set of diverse libraries. Initially, these have variability in only one of the three antigen-binding CDR regions of VH or VL and first round single domains are affinity matured by iterative randomization of the two other CDRs and reselection. We highlight the approach using a single domain binding to LMO2 protein. Our results show that interfering with LMO2 protein function demonstrates a role specifically in erythroid differentiation, confirm a necessary and sufficient function for LMO2 as a cancer therapy target in T-cell neoplasia and allowed for the first time production of soluble recombinant LMO2 protein by co-expression with intracellular domain antibodies. Co-crystallization of LMO2 and the anti-LMO2 VH protein was successful. These results demonstrate that this third generation IAC3 offers a robust toolbox for various biomedical applications and consolidates functional features of the LMO2 protein complex, which includes the importance of Lmo2-Ldb1 protein interaction. PMID:20980262

Tanaka, Tomoyuki; Sewell, Helen; Waters, Simon; Phillips, Simon E. V.; Rabbitts, Terence H.

2011-01-01

263

Pneumococcal vaccine and opsonic pneumococcal antibody.  

PubMed

Streptococcus pneumoniae is a major human pathogen responsible for the majority of bacterial pneumonia cases as well as invasive pneumococcal diseases with high mortality and morbidity. Use of conjugate vaccines targeting the pneumococcal capsule has dramatically reduced the incidence of invasive diseases, and there are active efforts to further improve the conjugate vaccines. However, in children new pneumococcal vaccines can no longer be tested with placebo-based clinical trials because effective vaccines are currently available. Thus, vaccine studies must depend on surrogate markers of vaccine efficacy. Although traditional antibody levels (e.g., ELISA) are useful as a surrogate marker of protection, they have limitations, and a bioassay measuring the capacity of antibodies to opsonize pneumococci has been developed. This opsonophagocytosis assay (OPA) replicates the in vivo mechanism of antibody protection and should therefore better reflect protection by vaccine-induced antibodies. Technical improvements of OPA have made this bioassay rapid, multiplexed, and practical for analyzing small samples including those from children. Strong correlations between ELISA and OPA have been observed in many studies of young children. However, poor correlations have been found in some important clinical situations (such as determination of protection by cross-reactive antibodies) and populations (such as elderly adults and immunodeficient patients). In these settings, OPA has become a useful supplementary measure of pneumococcal vaccine immunogenicity. Current efforts to standardize OPA will further expand its uses. PMID:23657429

Song, Joon Young; Moseley, M Allen; Burton, Robert L; Nahm, Moon H

2013-06-01

264

TSH receptor antibodies in autoimmune thyroiditis.  

PubMed

Out of 2,322 patients attending a thyroid clinic in north west Germany over a three year period, 123 were found to have evidence of autoimmune thyroiditis (hypothyroid, latent hypothyroid or euthyroid) and 96 were available for further analysis. TSH receptor antibodies (TRAb) were detectable by receptor assay in five of these patients (and a further two who attended the clinic later) and all the TRAb positive sera showed TSH blocking activity by bioassay. All of the patients with blocking activity were hypothyroid (on treatment) and represented 15% of this group of 34 patients. This suggests that in hypothyroid patients with autoimmune thyroiditis, the prevalence of TSH receptor antibodies with blocking activity is similar in northern Europe and Japan (21% of 43 patients; (1]. In the present study, no relationship between thyroid volume as assessed by sonography and the presence or absence of blocking antibodies was apparent. As blocking antibodies were undetectable in patients at early stages of the disease (i.e., in the euthyroid or latent hypothyroid groups) it seemed unlikely that these antibodies were a major causative factor in the development of hypothyroidism. PMID:3184158

Nordmeyer, J P; Hashim, F A; Shafeh, T; Eickenbusch, W; Rees Smith, B

1988-05-01

265

Antireticulin antibody: Incidence and diagnostic significance  

PubMed Central

Sera from 101 patients with adult coeliac disease, 46 patients with childhood coeliac disease, 50 patients with dermatitis herpetiformis, and 479 patients with various other diseases, including skin, gastrointestinal, haematological, and immunological disorders, have been tested for the presence of the antireticulin antibody. Positive sera were retested at higher dilutions. Antireticulin antibody was only found in a significant proportion of patients with three diseases, ie, coeliac disease, dermatitis herpetiformis, and Crohn's disease. Antireticulin antibody was present in 38 out of 101 patients (38%) with adult coeliac disease, 27 out of 46 patients (59%) with childhood coeliac disease, 11 out of 50 patients (22%) with dermatitis herpetiformis, and nine out of 38 patients (24%) with Crohn's disease. In the 434 other patients with various disorders the antireticulin antibody was present in only six 1·4%) (two patients were pregnant, one had vitiligo, one had tropical sprue, one had reticulum cell sarcoma, and one had pernicious anaemia). In patients with gluten-sensitive enteropathy, ie, coeliac disease and dermatitis herpetiformis, there was a significantly higher incidence in patients taking a normal diet compared with those on a gluten-free diet. The presence of antireticulin antibody would appear to be particularly helpful in diagnosing childhood coeliac disease as it was found in 22 out of 26 patients (85%) taking a normal diet. PMID:4574903

Seah, P. P.; Fry, Lionel; Holborow, E. J.; Rossiter, Mary A.; Doe, W. F.; Magalhaes, A. F.; Hoffbrand, A. V.

1973-01-01

266

The Antibody Response against HIV-1  

PubMed Central

Neutralizing antibodies (NAbs) typically play a key role in controlling viral infections and contribute to the protective effect of many successful vaccines. In the case of HIV-1 infection, there is compelling data in experimental animal models that NAbs can prevent HIV-1 acquisition, although there is no similar data in humans and their role in controlling established infection in humans is also limited. It is clear HIV-specific NAbs drive the evolution of the HIV-1 envelope glycoprotein within an infected individual. The virus’s ability to evade immune selection may be the main reason HIV-1 NAbs exert limited control during infection. The extraordinary antigenic diversity of HIV-1 also presents formidable challenges to defining NAbs that could provide broad protection against diverse circulating HIV-1 strains. Several new potent monoclonal antibodies (MAbs) have been identified, and are beginning to yield important clues into the epitopes common to diverse HIV-1 strains. In addition, antibodies can also act in concert with effector cells to kill HIV-infected cells; this could provide another mechanism for antibody-mediated control of HIV-1 replication. Understanding the impact of antibodies on HIV-1 transmission and pathogenesis is critical to helping move forward with rational HIV-1 vaccine design. PMID:22315717

Overbaugh, Julie; Morris, Lynn

2012-01-01

267

The F1000Research Antibody Validation Article Collection.  

PubMed

Well validated antibodies are crucial to progress in a wide range of life science disciplines, but validating an antibody is a complex and ongoing process. Antibody validation is often carried out as preliminary work to a larger study so the validation data may go unpublished and needless duplication of efforts can occur. This collection of articles in F1000Research provides a home for papers describing antibody validation studies. Our goal is to encourage publishing of all studies, both positive and negative, which increase understanding of how antibodies perform. These could range from large studies with thousands of antibodies to small single figure studies which validate an individual antibody for a specific purpose. Opinion or Correspondence articles considering any aspect of antibody validation are also welcome. Here, we provide an introduction to the collection which we hope will grow and become a valuable resource for the many thousands of researchers who use antibodies. PMID:25580229

Helsby, Matthew A; Leung, Mei Yee; Chalmers, Andrew D

2014-01-01

268

The F1000Research Antibody Validation Article Collection  

PubMed Central

Well validated antibodies are crucial to progress in a wide range of life science disciplines, but validating an antibody is a complex and ongoing process. Antibody validation is often carried out as preliminary work to a larger study so the validation data may go unpublished and needless duplication of efforts can occur. This collection of articles in F1000Research provides a home for papers describing antibody validation studies. Our goal is to encourage publishing of all studies, both positive and negative, which increase understanding of how antibodies perform. These could range from large studies with thousands of antibodies to small single figure studies which validate an individual antibody for a specific purpose. Opinion or Correspondence articles considering any aspect of antibody validation are also welcome. Here, we provide an introduction to the collection which we hope will grow and become a valuable resource for the many thousands of researchers who use antibodies. PMID:25580229

Helsby, Matthew A.; Leung, Mei Yee; Chalmers, Andrew D.

2014-01-01

269

Back to the future: recombinant polyclonal antibody therapeutics  

PubMed Central

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

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

2013-01-01

270

Antibody-specific model of amino Acid substitution for immunological inferences from alignments of antibody sequences.  

PubMed

Antibodies are glycoproteins produced by the immune system as a dynamically adaptive line of defense against invading pathogens. Very elegant and specific mutational mechanisms allow B lymphocytes to produce a large and diversified repertoire of antibodies, which is modified and enhanced throughout all adulthood. One of these mechanisms is somatic hypermutation, which stochastically mutates nucleotides in the antibody genes, forming new sequences with different properties and, eventually, higher affinity and selectivity to the pathogenic target. As somatic hypermutation involves fast mutation of antibody sequences, this process can be described using a Markov substitution model of molecular evolution. Here, using large sets of antibody sequences from mice and humans, we infer an empirical amino acid substitution model AB, which is specific to antibody sequences. Compared with existing general amino acid models, we show that the AB model provides significantly better description for the somatic evolution of mice and human antibody sequences, as demonstrated on large next generation sequencing (NGS) antibody data. General amino acid models are reflective of conservation at the protein level due to functional constraints, with most frequent amino acids exchanges taking place between residues with the same or similar physicochemical properties. In contrast, within the variable part of antibody sequences we observed an elevated frequency of exchanges between amino acids with distinct physicochemical properties. This is indicative of a sui generis mutational mechanism, specific to antibody somatic hypermutation. We illustrate this property of antibody sequences by a comparative analysis of the network modularity implied by the AB model and general amino acid substitution models. We recommend using the new model for computational studies of antibody sequence maturation, including inference of alignments and phylogenetic trees describing antibody somatic hypermutation in large NGS data sets. The AB model is implemented in the open-source software CodonPhyML (http://sourceforge.net/projects/codonphyml) and can be downloaded and supplied by the user to ProGraphMSA (http://sourceforge.net/projects/prographmsa) or other alignment and phylogeny reconstruction programs that allow for user-defined substitution models. PMID:25534034

Mirsky, Alexander; Kazandjian, Linda; Anisimova, Maria

2015-03-01

271

Engineered antibodies for molecular imaging of cancer  

PubMed Central

Antibody technology has transformed drug development, providing robust approaches to producing highly targeted and active therapeutics that can routinely be advanced through clinical evaluation and registration. In parallel, there is an emerging need to access similarly targeted agents for diagnostic purposes, including non-invasive imaging in preclinical models and patients. Antibody engineering enables modification of key properties (immunogenicity, valency, biological inertness, pharmacokinetics, clearance route, site-specific conjugation) in order to produce targeting agents optimized for molecular imaging. Expanded availability of positron-emitting radionuclides has led to a resurgence of interest and applications of immunoPET (immuno-positron emission tomography). Molecular imaging using engineered antibodies and fragments provides a general approach for assessing cell surface phenotype in vivo and stands to play an increasingly important role in cancer diagnosis, treatment selection, and monitoring of molecularly targeted therapeutics. PMID:24091005

Wu, Anna M.

2013-01-01

272

Unnatural amino acids in novel antibody conjugates.  

PubMed

Antibody-drug conjugates are an important and emerging drug class for the treatment of cancer. Recent evidence strongly suggests that site-specific drug conjugation results in a homogenous population of molecules with more favorable activity and pharmacokinetic properties than randomly conjugated antibodies. Unnatural amino acids (uAAs) can be incorporated in recombinant proteins to enable unique orthogonal chemistries in comparison to the side chains of the natural 20 amino acids. Thus, uAAs present a novel platform for which to create next-generation antibody-drug conjugates. Furthermore, site-specific conjugation through uAAs can also enpower unique small molecule, bispecific, multispecific and other conjugates that could be important constructs for therapeutics, diagnostics and research reagents. Here, we review the progress in uAA incorporation and conjugate construction through both cell-based and -free approaches. PMID:25163001

Hallam, Trevor J; Smider, Vaughn V

2014-07-01

273

Monoclonal antibodies against the aster yellows agent.  

PubMed

Hybridoma clones secreting specific monoclonal antibodies against the aster yellows agent, a mycoplasma-like organism, were produced by using partially purified salivary gland preparations from infected leafhopper vectors as the immunogen. After 3947 hybridomas from 20 independent fusions were screened for specific antibody against the aster yellows agent, two table clones were obtained. With these monoclonal antibodies the aster yellows agent in diseased lettuce, periwinkles, and inoculative insects was specifically identified by enzyme-linked immunosorbent assay. The aster yellows agent was serologically differentiated from the mycoplasma-like organisms associated with ash yellows, loofah witches'-broom, paulownia witches'-broom, sweet potato witches'-broom, peanut rosette, maize bushy stunt, and elm phloem necrosis. PMID:17757867

Lin, C P; An Chen, T

1985-03-01

274

Methods for conjugating antibodies to nanocarriers.  

PubMed

Antibodies are one of the most commonly used targeting ligands for nanocarriers, mainly because they are specific, have a strong binding affinity, and are available for a number of disease biomarkers. The bioconjugation chemistry can be a crucial factor in determining the targeting efficiency of drug delivery and should be chosen on a case-by-case basis. An antibody consists of a number of functional groups which offer many flexible options for bioconjugation. This chapter focuses on discussing some of the approaches including periodate oxidation, carbodiimide, maleimide, and heterofunctional linkers, for conjugating antibodies to different nanocarriers. The advantages and limitations are described herein. Specific examples are selected to demonstrate the experimental procedures and to illustrate the potential for applying to other nanocarrier system. PMID:23913152

Wagh, Anil; Law, Benedict

2013-01-01

275

Removal of Species Constraints in Antibody Detection ?  

PubMed Central

Serum antibodies from myriad species, particularly birds, can provide key information regarding the transmission and the expansion of the territory of emerging pathogens. Expedient antibody analysis is constrained by a lack of species-specific reagents, a deficiency potentially highlighted by the recent swine-origin influenza A virus (H1N1) outbreak. Available methodologies present difficulties that discourage thorough serologic monitoring of potential disease vectors or hosts. Rapid high-throughput procedures that combined serum amine labeling via biotinylation, contaminant removal, and microsphere-based immunoassays for antibodies to three arboviruses were developed. Agent-specific adaptations of this simple format should facilitate expanded surveillance and diagnostic capabilities regarding pathogens of human and veterinary importance. PMID:19923570

Basile, Alison Jane; Biggerstaff, Brad J.; Kosoy, Olga L.; Junna, Shilpa R.; Panella, Nicholas A.; Powers, Ann M.; Stark, Lillian M.; Nemeth, Nicole M.

2010-01-01

276

Current status of antibody therapy in ALL.  

PubMed

Despite the significant advances in modern chemotherapy, it remains challenging to treat adult patients with acute lymphoblastic leukaemia (ALL). The relapse rate remains high, and the outcome at the time of relapse is dismal. Antibody-based therapies have demonstrated promising results in this patient group. Variable mechanisms have been applied to target surface antigens (CD20 [also termed MS4A1], CD22, CD52 and CD19) that are commonly expressed on malignant leukaemia cells. In this review, we will focus on the clinical application of such therapies in adult ALL, including the naked antibodies: Rituximab, Ofatumumab, Epratuzumab and Alemtuzumab; the immunotoxins: BL22 and Combotox; the immunoconjugates: inotuzumab and SAR 3419; as well as the Bi-specific T cell engaging (BiTE)-specific antibody, Blinatumomab. PMID:25382151

Ai, Jing; Advani, Anjali

2015-02-01

277

Antibody-based biological toxin detection  

SciTech Connect

Fiber optic evanescent fluorosensors are under investigation in our laboratory for the study of drug-receptor interactions for detection of threat agents and antibody-antigen interactions for detection of biological toxins. In a direct competition assay, antibodies against Cholera toxin, Staphylococcus Enterotoxin B or ricin were noncovalently immobilized on quartz fibers and probed with fluorescein isothiocyanate (FITC) - labeled toxins. In the indirect competition assay, Cholera toxin or Botulinum toxoid A was immobilized onto the fiber, followed by incubation in an antiserum or partially purified anti-toxin IgG. These were then probed with FITC-anti-IgG antibodies. Unlabeled toxins competed with labeled toxins or anti-toxin IgG in a dose dependent manner and the detection of the toxins was in the nanomolar range.

Menking, D.E.; Goode, M.T. [Army Edgewood Research, Development and Engineering Center, Aberdeen Proving Ground, MD (United States)

1995-12-01

278

Antiphospholipid antibody syndrome and fetal outcome.  

PubMed

The presence of antiphospholipid antibodies, lupus anticoagulant and anticardiolipin antibody in patients with systemic lupus erythematosus has been associated with the clinical features of thrombosis, fetal loss and thrombocytopenia, and the syndrome is designated as antiphospholipid antibody syndrome (APS). APS has been increasingly diagnosed in patients without underlying autoimmune disease and is most frequently seen in obstetric patients suffering spontaneous abortion, preeclampsia and intrauterine growth restriction. The hypothesis underlying most research into the pathophysiology of APS is that autoantibodies are not only the markers of the disease, but also directly contribute to the development of clinical features. This review summarizes recent information on the pathophysiology and potential roles of autoantibodies in the obstetric patients suffering, particularly in the subgroup of repeated spontaneous abortions. PMID:11852731

Djelmis, J; Radonci?, E; Ivanisevi?, M

2001-01-01

279

Adsorption of monoclonal antibodies to glass microparticles.  

PubMed

Microparticulate glass represents a potential contamination to protein formulations that may occur as a result of processing conditions or glass types. The effect of added microparticulate glass to formulations of three humanized antibodies was tested. Under the three formulation conditions tested, all three antibodies adsorbed irreversibly at near monolayer surface coverages to the glass microparticles. Analysis of the secondary structure of the adsorbed antibodies by infrared spectroscopy reveal only minor perturbations as a result of adsorption. Likewise, front-face fluorescence quenching measurements reflected minimal tertiary structural changes upon adsorption. In contrast to the minimal effects on protein structure, adsorption of protein to suspensions of glass microparticles induced significant colloidal destabilization and flocculation of the suspension. PMID:20575075

Hoehne, Matthew; Samuel, Fauna; Dong, Aichun; Wurth, Christine; Mahler, Hanns-Christian; Carpenter, John F; Randolph, Theodore W

2011-01-01

280

Method for preparation of single chain antibodies  

DOEpatents

This invention provides a method for identifying cells expressing a target single chain antibody (scFv) directed against a target antigen from a collection of cells that includes cells that do not express the target scFv, comprising the step of combining the collection of cells with an anti-idiotype directed to an antibody specific for the target antigen and detecting interaction, if any, of the anti-idiotype with the cells, wherein the occurrence of an interaction identifies the cell as one which expresses the target scFv. This invention also provides a method for making a single chain antibody (scFv) directed against an antigen, wherein the selection of clones is made based upon interaction of those clones with an appropriate anti-idiotype, and heretofore inaccessible scFv so made. This invention provides the above methods or any combination thereof. Finally, this invention provides various uses of these methods.

Cheung, Nai-Kong V. (New York, NY); Guo, Hong-fen (New York, NY)

2012-04-03

281

Monoclonal antibodies specific for sickle cell hemoglobin  

SciTech Connect

Two mouse hybridoma cell lines were isolated which produce monoclonal antibodies that bind hemoglobin S. The mice were immunized with peptide-protein conjugates to stimulate a response to the amino terminal peptide of the beta chain of hemoglobin S, where the single amino acid difference between A and S occurs. Immunocharacterization of the antibodies shows that they bind specifically to the immunogen peptide and to hemoglobin S. The specificity for S is high enough that one AS cell in a mixture with a million AA cells is labeled by antibody, and such cells can be analyzed by flow cytometry. Immunoblotting of electrophoretic gels allows definitive identification of hemoglobin S as compared with other hemoglobins with similar electrophoretic mobility. 12 references, 4 figures.

Jensen, R.H.; Vanderlaan, M.; Grabske, R.J.; Branscomb, E.W.; Bigbee, W.L.; Stanker, L.H.

1985-01-01

282

Method for altering antibody light chain interactions  

DOEpatents

A method for recombinant antibody subunit dimerization including modifying at least one codon of a nucleic acid sequence to replace an amino acid occurring naturally in the antibody with a charged amino acid at a position in the interface segment of the light polypeptide variable region, the charged amino acid having a first polarity; and modifying at least one codon of the nucleic acid sequence to replace an amino acid occurring naturally in the antibody with a charged amino acid at a position in an interface segment of the heavy polypeptide variable region corresponding to a position in the light polypeptide variable region, the charged amino acid having a second polarity opposite the first polarity. Nucleic acid sequences which code for novel light chain proteins, the latter of which are used in conjunction with the inventive method, are also provided.

Stevens, Fred J. (Naperville, IL); Stevens, Priscilla Wilkins (Evanston, IL); Raffen, Rosemarie (Elmhurst, IL); Schiffer, Marianne (Downers Grove, IL)

2002-01-01

283

Antibody testing as a diagnostic tool in autonomic disorders.  

PubMed

Some forms of peripheral autonomic dysfunction (especially enteric neuropathy and subacute panautonomic failure) occur as autoimmune phenomena either in isolation or in the context of cancer. Autoimmune autonomic ganglionopathy is an example of a severe, but potentially treatable, antibody-mediated form of autonomic failure. Diagnostic evaluation of autonomic disorders can be supplemented by testing for paraneoplastic antibodies and antibodies against membrane receptors. The diagnostic antibodies most commonly associated with dysautonomia are paraneoplastic antibodies (anti-Hu and CRMP-5) and ganglionic acetylcholine receptor antibodies. PMID:18726055

Vernino, Steven

2009-02-01

284

Human proteasomes analysed with monoclonal antibodies.  

PubMed Central

The proteasome or multicatalytic endopeptidase from eukaryotic cells consists of at least 14 subunits that fall into two families, alpha and beta. Subunit-specific monoclonal antibodies against ten different subunits of human proteasomes have been produced, together with an antibody that reacts with a motif (prosbox 1), common to alpha-type subunits. Four of the subunit-specific antibodies were able to precipitate proteasomes. The subunit composition of HeLa-cell proteasomes precipitated with these four different antibodies were identical, as judged from two-dimensional electrophoresis. One of the four antibodies was used to obtain proteasomes from cell lines (HeLa, Daudi, IMR90 and BSC-1) and human tissues (placenta, kidney, and liver). Electrophoretic analysis of these proteasomes, combined with peptide mapping of some subunits, suggests that they all contain 14 types of subunits as their major constituents. However, one subunit was present in two isoelectric isoforms in all cells examined. Two other subunits occurred in two or three isoelectric isoforms in placenta, liver and kidney, but not in the cell cultures. Extracts of human cells (HeLa, IMR90, Daudi and erythrocytes) were analysed by non-denaturing electrophoresis and immunoblotting. All of the 11 subunits detected by antibodies were present in a pair of ATP-stabilized protein complexes, presumed to be the 26 S proteinase, and in a doublet of complexes which migrated more slowly than purified proteasomes. Besides being present in proteasomes, one subunit was also found to occur in the free state in cell extracts. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7826336

Hendil, K B; Kristensen, P; Uerkvitz, W

1995-01-01

285

Utility of feline coronavirus antibody tests.  

PubMed

Eight different tests for antibodies to feline coronavirus (FCoV) were evaluated for attributes that are important in situations in veterinary practice. We compared four indirect immunofluorescent antibody tests (IFAT), one enzyme-linked immunosorbent assay (ELISA) (FCoV Immunocomb; Biogal) and three rapid immunochromatographic (RIM) tests against a panel of samples designated by consensus as positive or negative. Specificity was 100% for all but the two IFATs based on transmissible gastroenteritis virus (TGEV), at 83.3% and 97.5%. The IFAT and ELISA tests were best for obtaining an antibody titre and for working in the presence of virus. The RIM tests were the best for obtaining a result quickly (10-15 mins); of these, the Speed F-Corona was the most sensitive, at 92.4%, followed by FASTest feline infectious peritonitis (FIP; 84.6%) and Anigen Rapid FCoV antibody test (64.1%). Sensitivity was 100% for the ELISA, one FCoV IFAT and one TGEV IFAT; and 98.2% for a second TGEV IFA and 96.1% for a second FCoV IFAT. All tests worked with effusions, even when only blood products were stipulated in the instruction manual. The ELISA and Anigen RIM tests were best for small quantities of sample. The most appropriate FCoV antibody test to use depends on the reason for testing: in excluding a diagnosis of FIP, sensitivity, specificity, small sample quantity, rapidity and ability to work in the presence of virus all matter. For FCoV screening, speed and sensitivity are important, and for FCoV elimination antibody titre is essential. PMID:24966245

Addie, Diane D; le Poder, Sophie; Burr, Paul; Decaro, Nicola; Graham, Elizabeth; Hofmann-Lehmann, Regina; Jarrett, Oswald; McDonald, Michael; Meli, Marina L

2015-02-01

286

Antibody-based diagnostic for ‘refractory’ periodontitis  

PubMed Central

Objective About 10–15% of US adults are ‘refractory’ to therapy for chronic periodontitis. Recently, studies suggest that these patients have elevated lysine decarboxylase activity in the sulcular microbiota. The aim of this study was to determine whether an elevated IgG antibody response to lysine decarboxylase, alone or with antibody to other bacterial antigens and baseline clinical measurements, would predict ‘refractory’ patients with high accuracy. Methods Chronic periodontitis patients were treated using scaling and root planing (SRP) followed by maintenance SRP and 3-monthly re-examinations. If there was a loss of mean full mouth attachment or more than three sites appeared with >2.5mm new loss within a year, the subjects were re-treated (modified Widman flap surgery and systemically administered tetracycline). If attachment loss as above recurred, the subjects were ‘refractory’. Baseline clinical measurements and specific antibody responses were used in a logistic regression model to predict ‘refractory’ subjects. Results Antibody to a peptide portion of lysine decarboxylase (HKL-Ab) and baseline bleeding on probing (BOP) prevalence measurements predicted attachment loss 3 months after initial therapy [pIAL = loss (0) or gain (1)]. IgG antibody contents to a purified antigen from Actinomyces spp. (A-Ab) and streptococcal d-alanyl glycerol lipoteichoic acid (S-Ab) were related in ‘refractory’ patients (R2 = 0.37, p < 0.01). From the regression equation, the relationship between the antibodies was defined as linear (pLA/S-Ab = 0) or non-linear pLA/S-Ab = 1). Using pLA/S-Ab, pIAL and age, a logistic regression equation was derived from 48 of the patients. Of 59 subjects, 37 had 2–4mm attachment loss and were assigned as ‘refractory’ or successfully treated with 86% accuracy. Conclusion HKL-Ab facilitated an accurate prediction of therapeutic outcome in subjects with moderate periodontitis. PMID:12445226

Levine, M.; LaPolla, S.; Owen, W.L.; Socransky, S.S.

2009-01-01

287

Therapeutic assessment of SEED: a new engineered antibody platform designed to generate mono- and bispecific antibodies.  

PubMed

The strand-exchange engineered domain (SEED) platform was designed to generate asymmetric and bispecific antibody-like molecules, a capability that expands therapeutic applications of natural antibodies. This new protein engineered platform is based on exchanging structurally related sequences of immunoglobulin within the conserved CH3 domains. Alternating sequences from human IgA and IgG in the SEED CH3 domains generate two asymmetric but complementary domains, designated AG and GA. The SEED design allows efficient generation of AG/GA heterodimers, while disfavoring homodimerization of AG and GA SEED CH3 domains. Using a clinically validated antibody (C225), we tested whether Fab derivatives constructed on the SEED platform retain desirable therapeutic antibody features such as in vitro and in vivo stability, favorable pharmacokinetics, ligand binding and effector functions including antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. In addition, we tested SEED with combinations of binder domains (scFv, VHH, Fab). Mono- and bivalent Fab-SEED fusions retain full binding affinity, have excellent biochemical and biophysical stability, and retain desirable antibody-like characteristics conferred by Fc domains. Furthermore, SEED is compatible with different combinations of Fab, scFv and VHH domains. Our assessment shows that the new SEED platform expands therapeutic applications of natural antibodies by generating heterodimeric Fc-analog proteins. PMID:21498564

Muda, Marco; Gross, Alec W; Dawson, Jessica P; He, Chaomei; Kurosawa, Emmi; Schweickhardt, Rene; Dugas, Melanie; Soloviev, Maria; Bernhardt, Anna; Fischer, David; Wesolowski, John S; Kelton, Christie; Neuteboom, Berend; Hock, Bjoern

2011-05-01

288

Aglycosylated antibodies and antibody fragments produced in a scalable in vitro transcription-translation system  

PubMed Central

We describe protein synthesis, folding and assembly of antibody fragments and full-length aglycosylated antibodies using an Escherichia coli-based open cell-free synthesis (OCFS) system. We use DNA template design and high throughput screening at microliter scale to rapidly optimize production of single-chain Fv (scFv) and Fab antibody fragments that bind to human IL-23 and IL-13?1R, respectively. In addition we demonstrate production of aglycosylated immunoglobulin G (IgG1) trastuzumab. These antibodies are produced rapidly over several hours in batch mode in standard bioreactors with linear scalable yields of hundreds of milligrams/L over a 1 million-fold change in scales up to pilot scale production. We demonstrate protein expression optimization of translation initiation region (TIR) libraries from gene synthesized linear DNA templates, optimization of the temporal assembly of a Fab from independent heavy chain and light chain plasmids and optimized expression of fully assembled trastuzumab that is equivalent to mammalian expressed material in biophysical and affinity based assays. These results illustrate how the open nature of the cell-free system can be used as a seamless antibody engineering platform from discovery to preclinical development of aglycosylated monoclonal antibodies and antibody fragments as potential therapeutics. PMID:22377750

Yin, Gang; Garces, Eudean D; Yang, Junhao; Zhang, Juan; Tran, Cuong; Steiner, Alexander R; Roos, Christine; Bajad, Sunil; Hudak, Susan; Penta, Kalyani; Zawada, James; Pollitt, Sonia

2012-01-01

289

Natural Killer Cell Mediated Antibody-Dependent Cellular Cytotoxicity in Tumor Immunotherapy with Therapeutic Antibodies  

PubMed Central

In the last decade several therapeutic antibodies have been Federal Drug Administration (FDA) and European Medicines Agency (EMEA) approved. Although their mechanisms of action in vivo is not fully elucidated, antibody-dependent cellular cytotoxicity (ADCC) mediated by natural killer (NK) cells is presumed to be a key effector function. A substantial role of ADCC has been demonstrated in vitro and in mouse tumor models. However, a direct in vivo effect of ADCC in tumor reactivity in humans remains to be shown. Several studies revealed a predictive value of Fc?RIIIa-V158F polymorphism in monoclonal antibody treatment, indicating a potential effect of ADCC on outcome for certain indications. Furthermore, the use of therapeutic antibodies after allogeneic hematopoietic stem cell transplantation is an interesting option. Studying the role of the Fc?RIIIa-V158F polymorphism and the influence of Killer-cell Immunoglobuline-like Receptor (KIR) receptor ligand incompatibility on ADCC in this approach may contribute to future transplantation strategies. Despite the success of approved second-generation antibodies in the treatment of several malignancies, efforts are made to further augment ADCC in vivo by antibody engineering. Here, we review currently used therapeutic antibodies for which ADCC has been suggested as effector function. PMID:23543707

Seidel, Ursula J. E.; Schlegel, Patrick; Lang, Peter

2013-01-01

290

Bispecific Antibodies: Developments and Current Perspectives  

Microsoft Academic Search

\\u000a All naturally occurring antibodies are multifunctional molecules, combining antigen-binding activity and Fc-mediated effector\\u000a functions within a single molecule (Schroeder and Cavacini 2010). Antigen binding can lead to direct neutralization of the\\u000a antigen, i.e., being antagonistic, but can also have agonistic activities, e.g., through activation of receptors (Fig. 1.1).\\u000a The Fc region is capable of mediating further effector functions, which include antibody-dependent

Roland E. Kontermann

291

Effects of interferon on antibody formation  

NASA Technical Reports Server (NTRS)

Studies of the effects of interferon on primary and secondary antibody responses and of the relationship of interferon to other cytokines, or cell products, are presented. Dosage- and timing-dependent immunoenhancing and immunosuppressive activities of interferon are documented for mouse spleen cell cultures and for mice infected with murine hepatitis virus (MHV-3). A possibility that altered interferon production might lead to immunopathological disorders, such as lupus erythematosus, AIDS, arthritis, etc., is discussed. Latest technological developments are presented that indicate that interferon does apparently play a major role in the regulation of antibody responses.

Sonnenfeld, G.

1984-01-01

292

Antibodies for Treatment of Clostridium difficile Infection  

PubMed Central

Antibodies for the treatment of Clostridium difficile infection (CDI) have been demonstrated to be effective in the research and clinical environments. Early uncertainties about molecular and treatment modalities now appear to have converged upon the systemic dosing of mixtures of human IgG1. Although multiple examples of high-potency monoclonal antibodies (MAbs) exist, significant difficulties were initially encountered in their discovery. This minireview describes historical and contemporary MAbs and highlights differences between the most potent MAbs, which may offer insight into the pathogenesis and treatment of CDI. PMID:24789799

Wilcox, Mark H.

2014-01-01

293

Antibody-drug conjugates: present and future.  

PubMed

Antibody-drug conjugates (ADCs) are becoming an increasingly important sub-class of antibody-related therapeutics. Two ADCs, brentuximab vedotin (Adcetris) and ado-trastuzumab emtansine (Kadcyla), were recently approved for marketing both by the US Food and Drug Administration (FDA) and the European Medicine Agency (EMA). Brentuximab vedotin is marketed as therapy for hematological malignancies (Hodgkin lymphoma, systemic anaplastic large cell lymphoma), while ado-trastuzumab emtansine is marketed for treatment of a solid tumor (breast cancer). The approvals of these two ADCs followed the mitigated success of gemtuzumab ozogamicin (Mylotarg), which was withdrawn from the US market in 2010, ten years after approval by the FDA. PMID:24423577

Beck, Alain; Reichert, Janice M

2014-01-01

294

Schmallenberg virus antibodies detected in Poland.  

PubMed

Between 24 and 30 July 2012 230 adult goats from three western provinces of Poland bordering on Germany (Western Pomerania, Lubuskie and Lower Silesia) were blood-sampled and tested for antibodies to Schmallenberg virus (SBV) using indirect immunoenzymatic test (ID Screen® Schmallenberg virus indirect, IDvet Innovative Diagnostics). The ELISA test identified 21 seropositive goats - 15 in Western Pomerania (16% of all goats tested in this province), five in Lubuskie (6%) and one in Lower Silesia (2%). Our study demonstrates for the first time the presence of antibodies to SBV in Poland. PMID:23302324

Kaba, J; Czopowicz, M; Witkowski, L

2013-02-01

295

THE FORMATION AND PROPERTIES OF POLIOVIRUS-NEUTRALIZING ANTIBODY. IV. NORMAL ANTIBODY AND EARLY IMMUNE ANTIBODY OF RABBIT ORIGIN: A COMPARISON OF BIOLOGICAL AND PHYSICOCHEMICAL PROPERTIES.  

PubMed

Rabbit sera were found to possess neutralizing activity (normal antibody) to polioviruses and Coxsackie B viruses. This normal antibody showed high specificity in cross-neutralization and absorption tests. It was associated with heat-stable, mercaptan-sensitive, 19S gamma(1)-beta-macroglobulins, which formed weak complexes with the viral antigen. In rare instances, sera with normal macroglobulin antibody, also contained very low activity which was due to 7S gamma(2)-globulins. The neutralization of poliovirus by normal 19S gamma(1)-beta-antibody appeared to follow first order kinetics, and the thermodynamic parameters of this reaction were the same as those of serological reactions employing immune antibody. The electrophoretic mobility, sedimentation properties, sensitivity to mercaptan, thermostability, and avidity of normal and early (up to day 3) immune antibodies to poliovirus were similar, but differed in several respects from those of late immune antibodies. Thus, the available evidence suggested, that earlier reported differences between normal and immune antibodies reflected differences between antibodies of diverse physicochemical properties rather than between normal and immune antibodies per se. It is proposed that the normal macroglobulin antibody is associated with an immunological response to repeated stimulation with minute amounts of antigen. PMID:14151096

SVEHAG, S E

1964-04-01

296

The production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi  

PubMed Central

In this review we will focus on the current status and views concerning the production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi. We will focus on single-chain antibody fragment production (scFv and VHH) by these lower eukaryotes and the possible applications of these proteins. Also the coupling of fragments to relevant enzymes or other components will be discussed. As an example of the fusion protein strategy, the 'magic bullet' approach for industrial applications, will be highlighted. PMID:12605725

Joosten, Vivi; Lokman, Christien; van den Hondel, Cees AMJJ; Punt, Peter J

2003-01-01

297

IgA antibody response during acquired and congenital toxoplasmosis.  

PubMed Central

Toxoplasma gondii specific IgA and IgM antibodies were quantitated by an antibody capture agglutination assay in 260 patients with acquired toxoplasmosis and from 94 fetuses suspected of congenital toxoplasmosis and 30 infected children. In acquired toxoplasmosis, IgA antibodies to T gondii were found in 95% of the cases. In congenital toxoplasmosis IgA antibodies were more frequently detected (75%) in cord blood than IgM antibodies (61%). They persisted after birth, in some cases for up to 24 months. IgA antibodies were also detected in fetuses whose mothers had toxoplasmosis during their pregnancy. In infected fetuses IgM and IgA antibodies were detected in fetal blood as early as week 24 of pregnancy. Detection of IgA T gondii antibodies may be useful for the diagnosis of some recently acquired infection and for the diagnosis and follow up of the infection in the fetus and neonate. PMID:1517461

Bessičres, M. H.; Roques, C.; Berrebi, A.; Barre, V.; Cazaux, M.; Séguéla, J. P.

1992-01-01

298

Antibody-based therapies for emerging infectious diseases.  

PubMed Central

In the 19th century, it was discovered that immune sera were useful in treating infectious diseases. Serum therapy was largely abandoned in the 1940s because of the toxicity associated with the administration of heterologous sera and the introduction of effective antimicrobial chemotherapy. Recent advances in the technology of monoclonal antibody production provide the means to generate human antibody reagents and reintroduce antibody therapies, while avoiding the toxicities associated with serum therapy. Because of the versatility of antibodies, antibody-based therapies could, in theory, be developed against any existing pathogen. The advantages of antibody-based therapies include versatility, low toxicity, pathogen specificity, enhancement of immune function, and favorable pharmacokinetics; the disadvantages include high cost, limited usefulness against mixed infections, and the need for early and precise microbiologic diagnosis. The potential of antibodies as antiinfective agents has not been fully tapped. Antibody-based therapies constitute a potentially useful option against newly emergent pathogens. PMID:8903230

Casadevall, A.

1996-01-01

299

[The current status of development of anti-EGFR antibodies].  

PubMed

The use of cetuximab, a mouse chimeric immunoglobulin G1 monoclonal antibody, is approved as anti-epidermal growth factor receptor(EGFR)therapy for the treatment of metastatic colorectal cancer in Japan. Further, panitumumab, matuzumab, nimotuzumab and zalutumumab which also target EGFR, are currently under clinical development. Cetuximab is the first that has been developed as an anti-EGFR antibody. Approximately 30% of the protein which constructs the mouse chimeric antibodies is from mouse, which yields the possibility that the mouse chimeric antibodies induce host immune-reaction. After cetuximab, the humanized monoclonal antibodies such as matuzumab and nimotuzumab, and fully humanized monoclonal antibodies such as panitumumab and zalutumumab, have been developed. In this article, we will introduce the current status of development of these four anti-EGFR antibodies, by focusing on the individual clinical trials using each anti-EGFR antibody. PMID:20495305

Ura, Takashi

2010-05-01

300

Quantitative analysis of perivascular antibody distribution in solid tumors  

E-print Network

Monoclonal antibodies and proteins derived from them are an emerging class of anticancer therapeutics that have shown efficacy in a range of blood and solid tumors. Antibodies targeting solid tumors face considerable ...

Rhoden, John J. (John Joseph)

2013-01-01

301

21 CFR 866.3290 - Gonococcal antibody test (GAT).  

Code of Federal Regulations, 2011 CFR

...intended to identify by immunochemical techniques, such as latex agglutination, indirect fluorescent antibody, or radioimmunoassay, antibodies to Neisseria gonorrhoeae in sera of asymptomatic females at low risk of infection....

2011-04-01

302

21 CFR 866.3290 - Gonococcal antibody test (GAT).  

Code of Federal Regulations, 2012 CFR

...intended to identify by immunochemical techniques, such as latex agglutination, indirect fluorescent antibody, or radioimmunoassay, antibodies to Neisseria gonorrhoeae in sera of asymptomatic females at low risk of infection....

2012-04-01

303

21 CFR 866.3290 - Gonococcal antibody test (GAT).  

Code of Federal Regulations, 2010 CFR

...intended to identify by immunochemical techniques, such as latex agglutination, indirect fluorescent antibody, or radioimmunoassay, antibodies to Neisseria gonorrhoeae in sera of asymptomatic females at low risk of infection....

2010-04-01

304

21 CFR 866.3290 - Gonococcal antibody test (GAT).  

...intended to identify by immunochemical techniques, such as latex agglutination, indirect fluorescent antibody, or radioimmunoassay, antibodies to Neisseria gonorrhoeae in sera of asymptomatic females at low risk of infection....

2014-04-01

305

Engineering aglycosylated antibody variants with immune effector functions  

E-print Network

Monoclonal antibodies have emerged as a promising class of therapeutics for the treatment of human disease, and in particular human cancer. While multiple mechanisms contribute to antibody efficacy, the engagement and ...

Sazinsky, Stephen L. (Stephen Lael)

2009-01-01

306

Magic Bullets and Monoclonals: An Antibody Tale  

NSDL National Science Digital Library

FASEB Breakthroughs in Bioscience article. This most recent article describes the century of fundamental immunology research that led to todayĂÂs cutting edge monoclonal antibody therapies, used to treat millions of patients for several types of cancer, autoimmune and inflammatory disorders, and infectious disease.

Margie Patlak (Federation of American Societies for Experimental Biology Office of Public Affairs)

2010-07-12

307

Mapping the prion protein using recombinant antibodies.  

PubMed

The fundamental event in prion disease is thought to be the posttranslational conversion of the cellular prion protein (PrPC) into a pathogenic isoform (PrPSc). The occurrence of PrPC on the cell surface and PrPSc in amyloid plaques in situ or in aggregates following purification complicates the study of the molecular events that underlie the disease process. Monoclonal antibodies are highly sensitive probes of protein conformation which can be used under these conditions. Here, we report the rescue of a diverse panel of 19 PrP-specific recombinant monoclonal antibodies from phage display libraries prepared from PrP deficient (Prnp0/0) mice immunized with infectious prions either in the form of rods or PrP 27-30 dispersed into liposomes. The antibodies recognize a number of distinct linear and discontinuous epitopes that are presented to a varying degree on different PrP preparations. The epitope reactivity of the recombinant PrP(90-231) molecule was almost indistinguishable from that of PrPC on the cell surface, validating the importance of detailed structural studies on the recombinant molecule. Only one epitope region at the C terminus of PrP was well presented on both PrPC and PrPSc, while epitopes associated with most of the antibodies in the panel were present on PrPC but absent from PrPSc. PMID:9765500

Williamson, R A; Peretz, D; Pinilla, C; Ball, H; Bastidas, R B; Rozenshteyn, R; Houghten, R A; Prusiner, S B; Burton, D R

1998-11-01

308

Bivalent antibody phage display mimics natural immunoglobulin.  

PubMed

We report the development of a system for displaying bivalent antibody fragments on M13 bacteriophage in a manner that effectively mimics the binding behavior of natural antibodies. In the "bivalent display" format, two copies of antigen binding sites are displayed on the coat of a single phage particle. Bivalent display was first achieved by the insertion of a dimerization domain, consisting of an IgG1 hinge region and a homodimerizing GCN4 leucine zipper, between a Fab and the C-terminal domain of the M13 gene-3 minor coat protein. In a phagemid-based display system, the resulting "Fab'-zip-phage" particles display bivalent Fabs that resemble natural IgGs. An important functional consequence of bivalent display is an avidity effect, which results in a greatly reduced off-rate for phage bound to immobilized antigen. The avidity effect improved the capture and retention of bivalent Fab'-zip-phage relative to monovalent Fab-phage both with antigen immobilized on plates and with cell surface antigen. To examine the requirements for bivalent display on phage, we systematically trimmed down the dimerization domain and found that a single cysteine was sufficient to confer the same avidity effect conferred by the complete dimerization domain. Bivalent antibody phage display should be useful for many applications. In particular, the technology should aid in the production of antibodies against difficult antigens, and also, in selections that require dimerization for activity. PMID:14736422

Lee, Chingwei V; Sidhu, Sachdev S; Fuh, Germaine

2004-01-01

309

Trifunctional Triomab ® Antibodies for Cancer Therapy  

Microsoft Academic Search

\\u000a In the 1980s, two groups described in parallel and for the first time T-cell-redirecting bispecific antibodies (bsAbs) for\\u000a the elimination of tumor cells (Perez et al. 1985; Staerz et al. \\

Horst Lindhofer; Juergen Hess; Peter Ruf

310

Structure and specificity of lamprey monoclonal antibodies  

E-print Network

Structure and specificity of lamprey monoclonal antibodies Brantley R. Herrin*§ , Matthew N. Alder, December 10, 2007 (sent for review November 26, 2007) Adaptive immunity in jawless vertebrates (lamprey in both lamprey and hagfish (1­3). The germline VLR genes are incomplete in that they have coding regions

Ronquist, Fredrik

311

Monoclonal antibodies against chicken interleukin-6  

Technology Transfer Automated Retrieval System (TEKTRAN)

Monoclonal antibodies (mAb) were produced against a recombinant (r) chicken interleukin-6 (IL-6). Eight mAbs that were produced were tested for isotype; ability to inhibit recombinant forms of chicken (ch), human (h) and murine (m) IL-6; and recognition of rchIL-6 by Western immunoblotting. The mA...

312

Structure-specific antibodies using epitope scaffolds  

E-print Network

Structure-specific antibodies using epitope scaffolds Epitopes, or the antigenic portions technique to graft an epitope of the envelope glycoprotein of HIV-1 onto protein scaffolds engineered for optimal structural stability and epitope exposure. The epitope is recognized by the HIV-1 neutralizing

El-Naggar, Moh

313

IgA Antibodies in Rett Syndrome  

ERIC Educational Resources Information Center

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

Reichelt, K. L.; Skjeldal, O.

2006-01-01

314

Single-Chain Fragment Variable Antibody Piezoimmunosensors  

E-print Network

on its surface. The recombinant single-chain fragment variable (scFv) antibody contained a cysteine of cysteine induced the scFv construct to self-assemble as a densely packed rigid monolayer on the gold surface of a quartz crystal mi- crobalance. scFv molecules in this self-assembled mono- layer (SAM

Stryker, Gabrielle A.

315

Antibody elution from red blood cells  

Microsoft Academic Search

An elution technique is described which gives eluates at least as potent as previously described methods. Elution can be completed in only 15 minutes. The method, a modification of that of Vos and Kelsall, is simple to carry out and requires the minimum of equipment. Studies have shown that the coating antibody is almost, but not completely, eluted.

Harry Rubin

1963-01-01

316

Immunostimulatory antibodies: Challenging the drug testing paradigm  

Microsoft Academic Search

The recently failed first-in-man clinical trial of TGN1412 raises concerns about whether the existing drug testing paradigm is suited to the safety assessment of drugs based on immunostimulatory antibodies that have complex and novel mechanisms of action. In particular, there is a need to consider whether animal studies are relevant and, if so, how the resulting information can be used

N. Bhogal; R. Combes

2007-01-01

317

SPECT assay of radiolabeled monoclonal antibodies  

SciTech Connect

The accurate determination of the biodistribution of radiolabeled monoclonal antibodies (MoAbs) is important for calculation of dosimetry and evaluation of pharmacokinetic variables such as antibody dose and route of administration. The hypothesis of this application is that the biodistribution of radiolabeled monoclonal antibodies (MoAbs) can be quantitatively determined using single photon emission computed tomography (SPECT). The major thrusts during the third year include the continued development and evaluation of improved 3D SPECT acquisition and reconstruction approaches to improve quantitative imaging of radiolabeled monoclonal antibodies (MoAbs), and the implementation and evaluation of algorithms to register serial SPECT image data sets, or to register 3D SPECT images with 3D image data sets acquired from positron emission tomography (PEI) and magnetic resonance images (MRI). The research has involved the investigation of statistical models and iterative reconstruction algorithms that accurately account for the physical characteristics of the SPECT acquisition system. It is our belief that SPECT quantification can be improved by accurately modeling the physical processes such as attenuation, scatter, geometric collimator response, and other factors that affect the measured projection data.

Jaszczak, R.J.

1992-02-01

318

[Antibodies to Brucella in caspian seals].  

PubMed

As the result of the study of Caspian seals, the presence of antibodies to Brucella was detected in the blood serum of these animals. The annual dynamics of the proportion of seropositive animals was noted. These data indicate the possibility of the circulation of the infective agent of brucellosis in the population of Caspian seals. PMID:15636154

Durymanova, A A; Dimov, S K; Kuznetsov, V N; Khuras'kin, L N; Zolotykh, S I; Shestopalov, A M

2004-01-01

319

World Antibody Drug Conjugate Summit Europe  

PubMed Central

The World Antibody Drug Conjugate Summit Europe, organized by Biorbis/Hanson Wade was held in Frankfurt, Germany February 21–23, 2011. Antibody drug conjugates (ADCs), also called immunoconjugates, are becoming an increasingly important class of therapeutics as demonstrated by the attendance of nearly 100 delegates at this highly focused meeting. Updates on three ADCs that are in late-stage clinical development, trastuzumab emtansine (T-DM1), brentuximab vedotin (SGN-35) and inotuzumab ozogamicin (CMC-544), were presented by speakers from ImmunoGen, Genentech, Roche, Seattle Genetics and Pfizer. These ADCs have shown encouraging therapeutic effects against solid tumors (T-DM1) and hematological malignancies (SGN-35, CMC-544). The key feature of the new generation of ADCs is the effective combination of the cytotoxicity of natural or synthetic highly potent antineoplastic agents, tumor selective monoclonal antibodies and blood-stable optimized linkers. Early clinical data for ADCs were showcased by Progenics Pharmaceuticals (PSMA ADC), Celldex (CDX-011) and Biotest (BT-062). Takeda, MedImmune and sanofi-aventis outlined their strategies for process development and analytical characterization. In addition, presentations on duocarmycin based-ADCs, ? emitting immunoconjugates and antibody-conjugated nanoparticles were given by representatives from Syntarga, Algeta and the University of Stuttgart, respectively. PMID:21691144

2011-01-01

320

Automated Aufbau of antibody structures from given sequences using Macromoltek's SmrtMolAntibody.  

PubMed

This study was a part of the second antibody modeling assessment. The assessment is a blind study of the performance of multiple software programs used for antibody homology modeling. In the study, research groups were given sequences for 11 antibodies and asked to predict their corresponding structures. The results were measured using root-mean-square deviation (rmsd) between the submitted models and X-ray crystal structures. In 10 of 11 cases, the results using SmrtMolAntibody show good agreement between the submitted models and X-ray crystal structures. In the first stage, the average rmsd was 1.4 Ĺ. Average rmsd values for the framework was 1.2 Ĺ and for the H3 loop was 3.0 Ĺ. In stage two, there was a slight improvement with an rmsd for the H3 loop of 2.9 Ĺ. PMID:24777752

Berrondo, Monica; Kaufmann, Susana; Berrondo, Manuel

2014-08-01

321

Human monoclonal antibodies against amyloid-beta from healthy adults  

Microsoft Academic Search

Two anti-amyloid-beta human antibody-producing cell lines were established from amyloid-beta (A?)-selected lymphocytes from peripheral blood of healthy adults. ELISA and Western blot analysis showed that the monoclonal antibodies bound with high affinity to the 43 amino acid-long amyloid-beta peptide. The antigen epitope of these antibodies encountered within amino acids 1–16 of the amyloid-beta peptide. The antibodies did not bind to

Valeria Geylis; Vitaly Kourilov; Zeev Meiner; Inger Nennesmo; Nenad Bogdanovic; Michael Steinitz

2005-01-01

322

IgA antibody response during acquired and congenital toxoplasmosis  

Microsoft Academic Search

Toxoplasma gondii specific IgA and IgM antibodies were quantitated by an antibody capture agglutination assay in 260 patients with acquired toxoplasmosis and from 94 fetuses suspected of congenital toxoplasmosis and 30 infected children. In acquired toxoplasmosis, IgA antibodies to T gondii were found in 95% of the cases. In congenital toxoplasmosis IgA antibodies were more frequently detected (75%) in cord

M H Bessičres; C Roques; A Berrebi; V Barre; M Cazaux; J P Séguéla

1992-01-01

323

Antigen-Antibody Testing: A Visual Simulation or Virtual Reality  

NSDL National Science Digital Library

This exercise demonstrates the biological phenomenon of the formation of a precipitate when an antigen reacts with an antibody. The exercise can be used to illustrate the specificity of antigen-antibody reactions, showing that a precipitation reaction only occurs when an antibody reacts with the antigen that was used to induce the formation of the antibody. The exercise is also a general demonstration of diffusion.

Daniel L. Schadler (Oglethorpe University;)

2003-02-24

324

Renewable, recombinant antibodies to histone post-translational modifications  

PubMed Central

Variability in the quality of antibodies to histone post-translational modifications (PTMs) presents widely recognized hindrance in epigenetics research. Here, by using antibody engineering technologies we produced recombinant antibodies directed to the trimethylated lysine residues of histone H3 with high specificity and affinity and no lot-to-lot variation. These recombinant antibodies performed well in common epigenetics applications, and their high specificity enabled us to identify positive and negative correlations among histone PTMs. PMID:23955773

Hattori, Takamitsu; Taft, Joseph M.; Swist, Kalina M.; Luo, Hao; Witt, Heather; Slattery, Matthew; Koide, Akiko; Ruthenburg, Alexander J.; Krajewski, Krzysztof; Strahl, Brian D.; White, Kevin P.; Farnham, Peggy J.; Zhao, Yingming; Koide, Shohei

2013-01-01

325

Expression and purification of recombinant antibody formats and antibody fusion proteins.  

PubMed

In the laboratory-scale production of antibody fragments or antibody fusion proteins, it is often difficult to keep track on the most suitable affinity tags for protein purification from either prokaryotic or eukaryotic host systems. Here, we describe how such recombinant proteins derived from Escherichia coli lysates as well as HEK293 cell culture supernatants are purified by IMAC and by different affinity chromatography methods based on fusions to FLAG-tag, Strep-tag, and Fc domains. PMID:24515473

Siegemund, Martin; Richter, Fabian; Seifert, Oliver; Unverdorben, Felix; Kontermann, Roland E

2014-01-01

326

Specific antibody filter (SAF) binding capacity enhancement to remove anti-A antibodies.  

PubMed

Removal of Anti-A/B antibodies prior to ABO-incompatible transplantation can prevent hyperacute organ rejection. We are developing a specific antibody filter (SAF) device to selectively remove ABO blood group antibodies from the whole blood by utilizing immunoaffinity adsorption. The device consists of ultrafiltration hollow fiber membranes with synthetic antigens specific to bind blood group antibodies immobilized on the inner lumenal walls of the fibers. The aim of this study was to evaluate the effect of antigen molecular weight and surface activation process to increase the antibody binding capacity of the fiber membrane surface. A new higher molecular weight antigen Atri-pNSA-1000 compared with Atri-pNPA-30 (A-trisaccharide (Atri) conjugated to activated polymers of Mol. wt. 1000 kDa and 30 kDa, respectively) was employed to improve accessibility of the antigen to bind antibodies. Also, a cyanogen bromide (CNBr) based surface activation method mediated by TEA in neutral pH medium was used to enhance the number of active sites for antigen binding compared to a strong basic medium of NaOH. Using a CNBr/TEA activation method and by immobilizing Atri-pNSA-1000 antigen, an antibody binding capacity (?0.01 monoclonal anti-A IgM nmol/cm(2)) was achieved on the fiber surface. This binding capacity was sufficient to reduce monoclonal antibody titer from 1:128 to final titer below 1:4 with a surface area to volume ratio that is similar to commercial dialysis device (?1.1 m(2) surface area for an average body blood volume of 5 L). PMID:20878917

Gautam, Shalini; Korchagina, Elena Y; Bovin, Nicolai V; Federspiel, William J

2010-11-01

327

A general affinity method to purify peroxidase-tagged antibodies  

Microsoft Academic Search

Antibodies tagged with enzymes, e.g. horseradish peroxidase (HRPO) are used extensively in a broad range of immunoassay, immunohistochemical, and prodrug-based immunotherapeutic applications. These antibodies may be polyclonal, monoclonal, bispecific or genetically engineered in origin. Often, purification of the antibody is the single greatest obstacle to obtaining immunoprobes with high specific activity [Milstein and Cuello, Nature 305 (1983) 537]. We have

Donald R Husereau; Mavanur R Suresh

2001-01-01

328

Beyond natural antibodies: the power of in vitro display technologies  

Microsoft Academic Search

In vitro display technologies, best exemplified by phage and yeast display, were first described for the selection of antibodies some 20 years ago. Since then, many antibodies have been selected and improved upon using these methods. Although it is not widely recognized, many of the antibodies derived using in vitro display methods have properties that would be extremely difficult, if

Sachdev Sidhu; Stefan Dübel; John McCafferty; Andrew R M Bradbury

2011-01-01

329

Bispecific Antibodies: Molecules That Enable Novel Therapeutic Strategies  

Microsoft Academic Search

Bispecific antibodies are unique in the sense that they can bind simultaneously two different antigens. This property enables the development of therapeutic strategies that are not possible with conventional monoclonal antibodies. The large panel of imaginative bispecific antibody formats that has been developed reflects the strong interest for these molecules. Although in many cases the manufacturing of clinical grade material

Nicolas Fischer; Olivier Léger

2007-01-01

330

Detection of Antibodies to Melanocytes in Vitiligo by Specific Immunoprecipitation  

Microsoft Academic Search

Immunoprecipitation was used to assay for antibodies to normal human melanocytes in the sera of 12 patients with common vitiligo and 12 normal individuals. The procedure is based on the specific immunoprecipitation using protein A-sepharose of antibodies binding to detergent-soluble, radioiodinated macromolecules of normal human melanocytes grown in culture. Antibodies to melanocytes were found in all 12 patients with vitiligo

Gail K. Naughton; Magdalena Eisinger; Jean-Claude Bystryn

1983-01-01

331

Antibody-mediated injury to proximal tubules in Heymann nephritis  

Microsoft Academic Search

Antibody-mediated injury to proximal tubules in Heymann nephritis. To evaluate the hypothesis that antibody-mediated damage to proximal tubules (PT) could be a feature of Heymann nephritis (HN), we studied the kidneys of rats in different stages of the disease by light, immunofluorescence (IF), transmission, and scanning electron microscopy. The observations of morphology were correlated with titers of circulating antibodies directed

Donna L Mendrick; Bernice Noble; Jan R Brentjens; Giuseppe A Andres

1980-01-01

332

Specific Antibody Response to Oligomannosidic Epitopes in Crohn's Disease  

Microsoft Academic Search

Elevated antibody levels against the yeastSaccharomyces cerevisiaehave been reported in sera from patients with Crohn's disease and not with ulcerative colitis. The aim of the study was to identify the nature of the epitopes supporting this antibody response. Whole cells from different S. cerevisiae strains were selected in immunofluorescence assay for their ability to differentiate the antibody responses of patients

B. SENDID; J. F. COLOMBEL; P. M. JACQUINOT; C. FAILLE; J. FRUIT; A. CORTOT; D. LUCIDARME; D. CAMUS

1996-01-01

333

Monoclonal antibody specific for a pigmentation associated antigen  

SciTech Connect

Monoclonal antibody TA99, which specifically binds to a pigmentation associated antigen present on melanoma cells is described. Additionally, the hybridoma cell line deposited with the ATCC under Accession Number HB 8704 from which the antibody is derived, as well as methods for using the antibody are described.

Thomson, T.M.; Mattes, M.J.; Old, L.J.; Lloyd, K.O

1989-01-17

334

FINAL REPORT. ENGINEERED ANTIBODIES FOR MONITORING OF POLYNUCLEAR AROMATIC HYDROCARBONS  

EPA Science Inventory

This project was conducted to remove the major barrier to the timely development and use of more versatile antibody-based detection and sample cleanup methods. The main objective was to adapt combinatorial antibody library and antibody engineering methods for preparing a panel of...

335

Specificity, polyspecificity, and heterospecificity of antibody-antigen recognition.  

PubMed

The concept of antibody specificity is analyzed and shown to reside in the ability of an antibody to discriminate between two antigens. Initially, antibody specificity was attributed to sequence differences in complementarity determining regions (CDRs), but as increasing numbers of crystallographic antibody-antigen complexes were elucidated, specificity was analyzed in terms of six antigen-binding regions (ABRs) that only roughly correspond to CDRs. It was found that each ABR differs significantly in its amino acid composition and tends to bind different types of amino acids at the surface of proteins. In spite of these differences, the combined preference of the six ABRs does not allow epitopes to be distinguished from the rest of the protein surface. These findings explain the poor success of past and newly proposed methods for predicting protein epitopes. Antibody polyspecificity refers to the ability of one antibody to bind a large variety of epitopes in different antigens, and this property explains how the immune system develops an antibody repertoire that is able to recognize every antigen the system is likely to encounter. Antibody heterospecificity arises when an antibody reacts better with another antigen than with the one used to raise the antibody. As a result, an antibody may sometimes appear to have been elicited by an antigen with which it is unable to react. The implications of antibody polyspecificity and heterospecificity in vaccine development are pointed out. PMID:25277087

Van Regenmortel, Marc H V

2014-11-01

336

Monoclonal antibodies and method for detecting dioxins and dibenzofurans  

DOEpatents

Compositions of matter are described which include five monoclonal antibodies that react with dioxins and dibenzofurans, and the five hybridomas that produce these monoclonal antibodies. In addition, a method for the use of these antibodies in a sensitive immunoassay for dioxins and dibenzofurans is given, which permits detection of these pollutants in samples at concentrations in the range of a few parts per billion.

Vanderlaan, Martin (San Ramon, CA); Stanker, Larry H. (Livermore, CA); Watkins, Bruce E. (Livermore, CA); Bailey, Nina R. (Berkley, CA)

1989-01-01

337

21 CFR 866.5100 - Antinuclear antibody immunological test system.  

Code of Federal Regulations, 2013 CFR

...antibody immunological test system. 866.5100 Section...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Immunological Test Systems § 866.5100 Antinuclear...antibody immunological test system is a device that consists...antibodies in serum, other body fluids, and...

2013-04-01

338

21 CFR 866.5100 - Antinuclear antibody immunological test system.  

...antibody immunological test system. 866.5100 Section...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Immunological Test Systems § 866.5100 Antinuclear...antibody immunological test system is a device that consists...antibodies in serum, other body fluids, and...

2014-04-01

339

Continuous cultures of fused cells secreting antibody of predefined specificity  

Microsoft Academic Search

THE manufacture of predefined specific antibodies by means of permanent tissue culture cell lines is of general interest. There are at present a considerable number of permanent cultures of myeloma cells1,2 and screening procedures have been used to reveal antibody activity in some of them. This, however, is not a satisfactory source of monoclonal antibodies of predefined specificity. We describe

G. Köhler; C. Milstein

1975-01-01

340

A Simple Model System to Demonstrate Antibody Structure and Functions.  

ERIC Educational Resources Information Center

A model that can be used to show the arrangement of light and heavy chains, disulfide linkages, domains, and subclass variations in antibodies is given. It can be constructed and modified to illustrate Fab, F(ab')2, and Fc fragments, single domain and bifunctional antibodies, and labeling of antibodies. (Author)

O'Kennedy, Richard

1991-01-01

341

Antibody titers predict clinical features of autoimmune autonomic ganglionopathy  

Microsoft Academic Search

Autoimmune autonomic ganglionopathy is a disorder of isolated autonomic failure associated with antibodies to the nicotinic acetylcholine receptor of the autonomic ganglia resulting in severe orthostatic intolerance, syncope, constipation, gastroparesis, urinary retention, dry mouth, dry eyes, blurred vision and anhidrosis. We report the autonomic test results, antibody titers and clinical findings in 8 patients with antibodies to the nicotinic acetylcholine

Christopher H. Gibbons; Roy Freeman

2009-01-01

342

Maternal transfer of antibodies: raising immuno-ecology issues  

Microsoft Academic Search

The transfer of antibodies from mother to offspring has broad potential implications in evolutionary ecology, from the adaptive value of maternal effects to the role of transgenerational plasticity in host-parasite inter- actions. Recent contributions have addressed key issues such as environmental and genetic factors affecting the amount of antibodies transferred and whether maternal antibodies affect offspring immunity, but little is

Thierry Boulinier; Vincent Staszewski

2008-01-01

343

The antibody repertoire in evolution: Chance, selection, and continuity  

Microsoft Academic Search

All jawed vertebrates contain the genetic elements essential for the function of the adaptive\\/combinatorial immune response, have diverse sets of natural antibodies resulting from segmental gene recombination, express comparable functional repertoires and can produce specific antibodies following appropriate immunization. Profound variability occurs in the third hypervariable (CDR3) segments of light and heavy chains even within antibodies of the same ostensible

John J. Marchalonis; Miranda K. Adelman; Samuel F. Schluter; Paul A. Ramsland

2006-01-01

344

Galactosylation variations in marketed therapeutic antibodies.  

PubMed

There are currently ~25 recombinant full-length IgGs (rIgGs) in the market that have been approved by regulatory agencies as biotherapeutics to treat various human diseases. Most of these are based on IgG1k framework and are either chimeric, humanized or human antibodies manufactured using either Chinese hamster ovary (CHO) cells or mouse myeloma cells as the expression system. Because CHO and mouse myeloma cells are mammalian cells, rIgGs produced in these cell lines are typically N-glycosylated at the conserved asparagine (Asn) residues in the CH2 domain of the Fc, which is also the case with serum IgGs. The Fc glycans present in these rIgGs are for the most part complex biantennary oligosaccharides with heterogeneity associated with the presence or the absence of several different terminal sugars. The major Fc glycans of rIgGs contain 0 or 1 or 2 (G0, G1 and G2, respectively) terminal galactose residues as non-reducing termini and their relative proportions may vary depending on the cell culture conditions in which they were expressed. Since glycosylation is strongly associated with antibody effector functions and terminal galactosylation may affect some of those functions, a panel of commercially available therapeutic rIgGs expressed in CHO cells and mouse myeloma cells were examined for their galactosylation patterns. The results suggest that the rIgGs expressed in CHO cells are generally less galactosylated compared to the rIgGs expressed in mouse myeloma cells. Accordingly, rIgGs produced in CHO cells tend to contain higher levels of G0 glycans compared with rIgGs produced in mouse myeloma cell lines. Despite the apparent wide variability in galactose content, adverse events or safety issues have not been associated with specific galactosylation patterns of therapeutic antibodies. Nevertheless, galactosylation may have an effect on the mechanisms of action of some therapeutic antibodies (e.g., effector pathways) and hence further studies to assess effects on product efficacy may be warranted for such antibodies. For antibodies that do not require effector functions for biological activity, however, setting a narrow specification range for galactose content may be unnecessary. PMID:22531450

Raju, T Shantha; Jordan, Robert E

2012-01-01

345

Serum antibody profiles of Sarcoptes scabiei infested or immunized rabbits.  

PubMed

The circulating antibody profiles of rabbits infected or immunized with Sarcoptes scabiei var. canis were compared. Crossed immuno-electrophoretic analysis showed that infested hosts produced serum antibody to 12 proteins (antigens) in an extract made from sarcoptic mite bodies. In contrast, rabbits immunized with an extract made from mite bodies produced antibody to 20 Sarcoptes proteins (antigens). SDS-PAGE/immunoblot analysis revealed that serum from immunized rabbits contained antibodies that bound strongly to proteins of 25 and 39-52 kD that were only barely visualized by antibodies in serum from infested rabbits. PMID:7883255

Morgan, M S; Arlian, L G

1994-01-01

346

DIAGNOSTIC VALUE OF ANTI-RA33 ANTIBODY, ANTIKERATIN ANTIBODY, ANTIPERINUCLEAR FACTOR AND ANTINUCLEAR ANTIBODY IN EARLY RHEUMATOID ARTHRITIS: COMPARISON WITH RHEUMATOID FACTOR  

Microsoft Academic Search

SUMMARY The goal of this prospective longitudinal study was to determine the serological profile of early rheumatoid arthritis (RA), and to test whether antikeratin antibody (AKA), antiperinuclear factor (API7), anti-RA33 antibody and antinuclear antibodies (ANA) had an additional diagnostic value when prescribed after rheumatoid factor (RF)-detecting methods. Sixty-nine patients with early polyarthritis suggestive of RA, seen between 1991 and 1993,

C. CORDONNIER; O. MEYER; E. PALAZZO; M. DE BANDT; A. ELIAS; P. NICAISE; T. HAĎM; M. F. KAHN; G. CHATELLIER

1996-01-01

347

Monoclonal antibodies against rabbit mammary prolactin receptors. Specific antibodies to the hormone binding domain  

SciTech Connect

Three monoclonal antibodies (M110, A82, and A917) were obtained by fusing myeloma cells and spleen cells from mice immunized with partially purified rabbit mammary gland prolactin (PRL) receptors. All 3 antibodies were capable of complete inhibition of SVI-ovine prolactin (oPRL) binding to rabbit mammary PRL receptors in either particulate or soluble form. M110 showed slightly greater potency than oPRL in competing for SVI-oPRL binding. These antibodies also inhibited PRL binding to microsomal fractions from rabbit liver, kidney, adrenal, ovary, and pig mammary gland, although A82 showed poor inhibition in pig mammary gland. There was no cross-reaction of any of the 3 monoclonal antibodies (mAbs) for the other species tested: human (T-47D breast cancer cells) and rat (liver, ovary). In order to confirm that these antibodies are specific to the binding domain, antibodies were purified, iodinated, and binding characteristics were investigated. SVI-M110 and SVI-A82 binding was completely inhibited by lactogenic hormones, whereas nonlactogenic hormones did not cross-react. Competition of 125I-M110 by oPRL was comparable to that of SVI-oPRL by unlabeled oPRL, while SVI-A917 binding was only partially competed (30-60%) by lactogenic hormones. Tissue and species specificity of labeled antibody binding paralleled results of binding inhibition experiments using 125I-oPRL. In addition, A82 and A917 completely inhibited 125I-M110 binding. In contrast, 125I-A82 binding was stimulated by A917 and 125I-A917 binding was stimulated by A82.

Katoh, M.; Djiane, J.; Kelly, P.A.

1985-09-25

348

Neutralizing antibody responses to varicella-zoster virus.  

PubMed Central

Neutralization of varicella-zoster (V-Z) virus by human sera and immune rhesus monkey sera was enhanced by fresh guinea pig complement. There was no marked difference in the degree to which complement enhanced neutralization by sera from current V-Z virus infections and sera from long-past varicella infections. Immunoglobulin G neutralizing antibody in sera from varicella cases was enhanced by complement to a slightly higher degree than was immunoglobulin M (IgM) antibody, and immunoglobulin G neutralizing antibody in immune monkey sera was enhanced to a much greater degree than was IgM antibody. There was a rapid decline in the complement requirement of IgM neutralizing antibodies over the course of immunization of the rhesus monkeys. V-Z neutralizing antibody titers in the presence of complement were higher than complement-fixing titers of the same sera in all groups of individuals studied. IgM neutralizing antibody for V-Z virus was demonstrable in all cases of varicella but in only 1 of 22 zoster cases, and V-Z IgM neutralizing antibody was not detectable in primary herpes simplex virus infections in which heterotypic antibody titer rises occurred to V-Z virus. Complement-fixing antibody for V-Z virus was absent in 19S serum fractions which contained IgM neutralizing antibody for the virus. PMID:170206

Schmidt, N J; Lennette, E H

1975-01-01

349

Serum Antibody Repertoire Profiling Using In Silico Antigen Screen  

PubMed Central

Serum antibodies are valuable source of information on the health state of an organism. The profiles of serum antibody reactivity can be generated by using a high throughput sequencing of peptide-coding DNA from combinatorial random peptide phage display libraries selected for binding to serum antibodies. Here we demonstrate that the targets of immune response, which are recognized by serum antibodies directed against sequential epitopes, can be identified using the serum antibody repertoire profiles generated by high throughput sequencing. We developed an algorithm to filter the results of the protein database BLAST search for selected peptides to distinguish real antigens recognized by serum antibodies from irrelevant proteins retrieved randomly. When we used this algorithm to analyze serum antibodies from mice immunized with human protein, we were able to identify the protein used for immunizations among the top candidate antigens. When we analyzed human serum sample from the metastatic melanoma patient, the recombinant protein, corresponding to the top candidate from the list generated using the algorithm, was recognized by antibodies from metastatic melanoma serum on the western blot, thus confirming that the method can identify autoantigens recognized by serum antibodies. We demonstrated also that our unbiased method of looking at the repertoire of serum antibodies reveals quantitative information on the epitope composition of the targets of immune response. A method for deciphering information contained in the serum antibody repertoire profiles may help to identify autoantibodies that can be used for diagnosing and monitoring autoimmune diseases or malignancies. PMID:23826227

Liu, Xinyue; Hu, Qiang; Liu, Song; Tallo, Luke J.; Sadzewicz, Lisa; Schettine, Cassandra A.; Nikiforov, Mikhail; Klyushnenkova, Elena N.; Ionov, Yurij

2013-01-01

350

Studies on production of anticollagen antibodies in silicosis  

SciTech Connect

Silicosis is characterized by pulmonary fibrotic changes which consist primarily of an increase in collagen. In this study, anticollagen antibodies in the serum of 134 silicosis patients versus 40 normal subjects were examined and their relationship with immunoglobulin, autoantibodies, and procollagen III peptide (PIIIP) was investigated by enzyme-linked immunosorbent assay (ELISA). The mean levels of antihuman type I collagen (HI) and anti-human type Ill collagen (HIII) antibodies were significantly higher in the silicosis patients versus the normal subjects (P < 0.001). However, no differences were observed in the mean levels of anti-human type IV collagen (HIV) antibodies in the silicosis patients versus the normal subjects. Anticollagen antibodies in the sera of silicosis patients appear to be formed at an early stage of the disease. We observed a correlation between anticollagen antibodies and immunoglobulin. There was a tendency toward high values of anticollagen antibodies in the sera of patients positive for antinuclear antibodies (ANA) and rheumatoid factor (RF), both of which are autoantibodies. However, no correlation was observed between serum PIIIP and anticollagen antibodies. These observations suggest that, in silicosis, there is a relationship between anticollagen antibodies and immunoglobulins, as well as between anticollagen antibodies and autoantibodies. Measurement of anticollagen antibodies in the sera of silicosis patients offers a useful index for evaluating the prognosis of pulmonary fibrosis and autoimmune abnormality in silicosis. 49 refs. 6 figs., 6 tabs.

Nagaoka, Tadasu; Tabata, Masaji; Kobayashi, Kenichi; Okada, Akira (Kanazawa Univ. (Japan))

1993-01-01

351

IBC’s 23rd Antibody Engineering and 10th Antibody Therapeutics Conferences and the Annual Meeting of The Antibody Society  

PubMed Central

Now in its 23rd and 10th years, respectively, the Antibody Engineering and Antibody Therapeutics conferences are the Annual Meeting of The Antibody Society. The scientific program covers the full spectrum of challenges in antibody research and development from basic science through clinical development. In this preview of the conferences, the chairs provide their thoughts on sessions that will allow participants to track emerging trends in (1) the development of next-generation immunomodulatory antibodies; (2) the complexity of the environment in which antibodies must function; (3) antibody-targeted central nervous system (CNS) therapies that cross the blood brain barrier; (4) the extension of antibody half-life for improved efficacy and pharmacokinetics (PK)/pharmacodynamics (PD); and (5) the application of next generation DNA sequencing to accelerate antibody research. A pre-conference workshop on Sunday, December 2, 2012 will update participants on recent intellectual property (IP) law changes that affect antibody research, including biosimilar legislation, the America Invents Act and recent court cases. Keynote presentations will be given by Andreas Plückthun (University of Zürich), who will speak on engineering receptor ligands with powerful cellular responses; Gregory Friberg (Amgen Inc.), who will provide clinical updates of bispecific antibodies; James D. Marks (University of California, San Francisco), who will discuss a systems approach to generating tumor targeting antibodies; Dario Neri (Swiss Federal Institute of Technology Zürich), who will speak about delivering immune modulators at the sites of disease; William M. Pardridge (University of California, Los Angeles), who will discuss delivery across the blood-brain barrier; and Peter Senter (Seattle Genetics, Inc.), who will present his vision for the future of antibody-drug conjugates. For more information on these meetings or to register to attend, please visit www.IBCLifeSciences.com/AntibodyEng or call 800-390-4078. Members of The Antibody Society and mAbs journal subscribers receive a 20% discount for meeting registration. To obtain this discount, email kdostie@ibcusa.com. mAbs is the official therapeutics journal of The Antibody Society and offers a discounted subscription to Society members for $49. PMID:23007482

Marquardt, John; Begent, Richard H.J.; Chester, Kerry; Huston, James S.; Bradbury, Andrew; Scott, Jamie K.; Thorpe, Philip E.; Veldman, Trudi; Reichert, Janice M.; Weiner, Louis M.

2012-01-01

352

IBC's 23rd Antibody Engineering and 10th Antibody Therapeutics Conferences and the Annual Meeting of The Antibody Society: December 2-6, 2012, San Diego, CA.  

PubMed

Now in its 23rd and 10th years, respectively, the Antibody Engineering and Antibody Therapeutics conferences are the Annual Meeting of The Antibody Society. The scientific program covers the full spectrum of challenges in antibody research and development from basic science through clinical development. In this preview of the conferences, the chairs provide their thoughts on sessions that will allow participants to track emerging trends in (1) the development of next-generation immunomodulatory antibodies; (2) the complexity of the environment in which antibodies must function; (3) antibody-targeted central nervous system (CNS) therapies that cross the blood brain barrier; (4) the extension of antibody half-life for improved efficacy and pharmacokinetics (PK)/pharmacodynamics (PD); and (5) the application of next generation DNA sequencing to accelerate antibody research. A pre-conference workshop on Sunday, December 2, 2012 will update participants on recent intellectual property (IP) law changes that affect antibody research, including biosimilar legislation, the America Invents Act and recent court cases. Keynote presentations will be given by Andreas Plückthun (University of Zürich), who will speak on engineering receptor ligands with powerful cellular responses; Gregory Friberg (Amgen Inc.), who will provide clinical updates of bispecific antibodies; James D. Marks (University of California, San Francisco), who will discuss a systems approach to generating tumor targeting antibodies; Dario Neri (Swiss Federal Institute of Technology Zürich), who will speak about delivering immune modulators at the sites of disease; William M. Pardridge (University of California, Los Angeles), who will discuss delivery across the blood-brain barrier; and Peter Senter (Seattle Genetics, Inc.), who will present his vision for the future of antibody-drug conjugates. For more information on these meetings or to register to attend, please visit www.IBCLifeSciences.com/AntibodyEng or call 800-390-4078. Members of The Antibody Society and mAbs journal subscribers receive a 20% discount for meeting registration. To obtain this discount, email kdostie@ibcusa.com. mAbs is the official therapeutics journal of The Antibody Society and offers a discounted subscription to Society members for $49. PMID:23007482

Marquardt, John; Begent, Richard H J; Chester, Kerry; Huston, James S; Bradbury, Andrew; Scott, Jamie K; Thorpe, Philip E; Veldman, Trudi; Reichert, Janice M; Weiner, Louis M

2012-01-01

353

Antibody Production and Catabolism in Uraemia  

PubMed Central

A method for the production of chronic uraemia in mice is described. Production of humoral antibody has been studied in uraemic mice in response to a primary and secondary challenge with sheep red cells and in response to intraperitoneal and subcutaneous bovine serum albumin (BSA) in complete Freund's adjuvant. In uraemic animals the response to sheep red cells was slightly reduced compared with controls in both the primary and secondary responses. Similarly, the responses to intraperitoneal BSA and subcutaneous BSA in adjuvant was slightly reduced in the uraemic group. The catabolic rate of purified [125I] mouse IgG was normal in uraemic animals, indicating that the lower titre of humoral antibody was not due to increased catabolism of immunoglobulin in uraemia. PMID:4726091

Souhami, R. L.

1973-01-01

354

Monoclonal antibody to growth hormone receptors  

SciTech Connect

Using hybridoma technology, monoclonal antibodies to growth hormone receptors can be prepared in large quantities with only a few micrograms of purified antigen by in vitro immunization or by immunization of larger quantities of less pure material. The discussion centers on areas most pertinent to receptors such as receptor preparation, immunization procedure, fusion method, screening assay, and identification of the immunoglobulin class. The specificity of the antibody for growth hormone receptor was examined by testing the ability of the ascitic fluid to inhibit binding of (/sup 125/I) growth hormone to the prolactin receptors on rabbit mammary gland membranes and the inhibition of /sup 125/I-labelled rat growth hormone binding to rabbit liver membrane.

Simpson, J.S.A.; Friesen, H.G.

1985-01-01

355

Fluorometric assay for red blood cell antibodies  

SciTech Connect

A fluorometric assay is described for the detection of red blood cell antibodies. The assay reveals as little as 600 molecules of bound, fluoroesceinated rabbit anti-human IgG antibodies per erythrocyte. Eleven patients with possible autoimmune erythrocyte disorder and negative direct antiglobulin test were studied by the fluorometric assay. The outcome of the fluorometric assay was compared with that of the human allogeneic rosette test. Results obtained by the two methods were in complete agreement. Five of the patients were shown to possess unexpectedly high levels of erythrocyte-bound IgG in spite of a negative, direct antiglobulin test. These findings and the validity of the fluorometric assay are discussed.

Schreiber, A.B.; Lambermont, M.; Strosberg, A.D.; Wybran, J.

1981-03-01

356

Innovative Monoclonal Antibody Therapies in Multiple Sclerosis  

PubMed Central

The recent years have witnessed great efforts in establishing new therapeutic options for multiple sclerosis (MS), especially for relapsing–remitting disease courses. In particular, the application of monoclonal antibodies provide innovative approaches allowing for blocking or depleting specific molecular targets, which are of interest in the pathogenesis of MS. While natalizumab received approval by the US Food and Drug Administration and the European Medicines Agency in 2006 as the first monoclonal antibody in MS therapy, rituximab, alemtuzumab, and daclizumab were successfully tested for relapsing-remitting MS in small cohorts in the meantime. Here, we review the data available from these recent phase II trials and at the same time critically discuss possible pitfalls which may be relevant for clinical practice. The results of these studies may not only broaden our therapeutic options in the near future, but also provide new insights into disease pathogenesis. PMID:21180564

Kieseier, Bernd C.

2008-01-01

357

Antibody immunosuppressive therapy in solid organ transplant  

PubMed Central

The use of antibodies in transplantation dates back to 1986 when muromonab CD3, a monoclonal antibody (mAb) targeting CD3, was first approved for prevention and treatment of renal allograft rejection. These agents have largely been used in a brief adjunctive manner to provide immunosuppression during the initial period after solid organ transplantation or during an episode of acute rejection. Recent advances in our understanding of transplant immunology have allowed emergence of numerous new mAbs, targeting co-stimulatory signals, cell surface receptors and novel protein constructs. During the next decade, transplant professionals will increasingly require knowledge of the mechanisms and pharmacologic characteristics of these novel therapeutic agents. PMID:20948291

Klipa, Dusko; Mahmud, Nadim

2010-01-01

358

Antibody enhancement of free-flow electrophoresis  

NASA Technical Reports Server (NTRS)

Specific T cell clones and antibodies (ABs) were developed to study the efficiency of purifying closely associated T cells using Continuous Flow Electrophoresis System. Enhanced separation is accomplished by tagging cells first with ABs directed against the antigenic determinants on the cell surface and then with ABs against the Fc portion of the first AB. This second AB protrudes sufficiently beyond the cell membrane and glycocalyx to become the major overall cell surface potential determinant and thus causes a reduction of electrophoretic mobility. This project was divided into three phases. Phase one included development of specific T cell clones and separation of these specific clones. Phase two extends these principles to the separation of T cells from spleen cells and immunized lymph node cells. Phase three applies this double antibody technique to the separation of T cytotoxic cells from bone marrow.

Cohly, H. H. P.; Morrison, Dennis R.; Atassi, M. Zouhair

1988-01-01

359

Recent developments in monoclonal antibody radiolabeling techniques  

SciTech Connect

Monoclonal antibodies (MAbs) have shown the potential to serve as selective carriers of radionuclides to specific in vivo antigens. Accordingly, there has been an intense surge of research activity in an effort to develop and evaluate MAb-based radiopharmaceuticals for tumor imaging (radioimmunoscintigraphy) and therapy (radioimmunotherapy), as well as for diagnosing nonmalignant diseases. A number of problems have recently been identified, related to the MAbs themselves and to radiolabeling techniques, that comprise both the selectivity and the specificity of the in vivo distribution of radiolabeled MAbs. This paper will address some of these issues and primarily discuss recent developments in the techniques for radiolabeling monoclonal antibodies that may help resolve problems related to the poor in vivo stability of the radiolabel and may thus produce improved biodistribution. Even though many issues are identical with therapeutic radionuclides, the discussion will focus mainly on radioimmunoscintigraphic labels. 78 refs., 6 tabs.

Srivastava, S.C.; Mease, R.C.

1989-01-01

360

[Cardiovascular abnormalities of the antiphospholipid antibody syndrome].  

PubMed

The antiphospholipid antibody syndrome (APS) may present with serious cardiovascular complications which should be recognised by the cardiologist. The authors report a series of 6 cases of APS diagnosed after thrombotic events and the finding of antiphospholipid antibodies. The APS was primary in 5 cases and associated with tuberculous lymphadenitis in 1 case. There was cardiac involvement in 5 patients with pericardial effusion in 3 cases, complicated by tamponade as the presenting sign of primary APS in the other 2, valvular disease in one case (moderate mitral stenosis with aortic valve disease) and pulmonary embolism in one case. Five patients developed recurrent deep vein thrombosis of the legs. One patient had a transient ischaemic cerebral attack. PMID:12741309

Noureddine, M; Bennis, A; Raquim, S; Tahiri, A; Chraibi, N

2003-04-01

361

Antibody-mediated cofactor-driven reactions  

DOEpatents

Chemical reactions capable of being rate-enhanced by auxiliary species which interact with the reactants but do not become chemically bound to them in the formation of the final product are performed in the presence of antibodies which promote the reactions. The antibodies contain regions within their antigen binding sites which recognize the auxiliary species in a conformation which promotes the reaction. The antigen binding site frequently recognizes a particular transition state complex or other high energy complex along the reaction coordinate, thereby promoting the progress of the reaction along the desired route as opposed to other less favorable routes. Various classes of reaction together with appropriate antigen binding site specificities tailored for each are disclosed.

Schultz, Peter G. (Oakland, CA)

1993-01-01

362

Monoclonal antibody targets, kills leukemia cells  

Cancer.gov

Researchers at the University of California, San Diego Moores Cancer Center have identified a humanized monoclonal antibody that targets and directly kills chronic lymphocytic leukemia (CLL) cells. The findings, published in the online Early Edition of the Proceedings of the National Academy of Sciences on March 25, 2013 represent a potential new therapy for treating at least some patients with CLL, the most common type of blood cancer in the United States.

363

Treatment of Hodgkin's disease with bispecific antibodies  

Microsoft Academic Search

Summary Bispecific monoclonal antibodies (Bi-MAbs) with dual spe- cificity for tumor-associated antigens (TAA) and a triggering molecule of an immunologic effector cell, respectively, open the possibility to specifically target to and activate cytotoxic effector cells (macrophages, T-cells, NK cells) at the rumor site. Using appropriately designed Bi-MAbs and unstimulat- ed human NK cells and T-cells, respectively, we were able to

F. Hartmann; C. Renner; W. Jung; U. Sahin; M. Pfreundschuh

1996-01-01

364

Generation of Bispecific Antibodies by Chemical Conjugation  

Microsoft Academic Search

\\u000a Bispecifc antibodies (bsAbs) are emerging as a promising new class of biotherapeutics. Although Ig domain fusion by DNA engineering\\u000a is the prevalent methodology for producing bsAbs, a significant number of studies are being performed with chemically crosslinked\\u000a Abs. By using different starting material and various conjugation strategies, bispecific fragments, full-length Abs, or combinations\\u000a thereof can be generated. Two types or

Diego Ellerman; Justin M. Scheer

365

Modulating the pharmacokinetics of therapeutic antibodies  

Microsoft Academic Search

With the advent of antibody fragments and alternative binding scaffolds, that are devoid of Fc-regions, strategies to increase\\u000a the half-life of small proteins are becoming increasingly important. Currently, the established method is chemical PEGylation,\\u000a but more elaborate approaches are being described such as polysialylation, amino acid polymers and albumin-binding derivatives.\\u000a This article reviews the main strategies for pharmacokinetic enhancement, primarily

A. Constantinou; C. Chen; M. P. Deonarain

2010-01-01

366

The biotechnology and applications of antibody engineering  

Microsoft Academic Search

The exquisite specificity of monoclonal antibodies (MAb) has long provided the potential for creating new reagents for the\\u000a in vivo delivery of therapeutic drugs or toxins to defined cellular target sites or improved methods of diagnosis. However,\\u000a many difficulties associated with their production, affinity, specificity, and use in vivo have largely confined their application\\u000a to research or in vitro diagnostics.

Ralph Rapley

1995-01-01

367

Antibody-Based Vascular Tumor Targeting  

Microsoft Academic Search

\\u000a The inhibition of angiogenesis represents a major step toward a more selective and better-tolerated therapy of cancer. An\\u000a alternative way to take advantage of a tumor’s absolute dependence on a functional neovasculature is illustrated by the strategy\\u000a of “antibody-based vascular tumor targeting.” This technology aims at the selective delivery of bioactive molecules to the\\u000a tumor site by their conjugation to

Christoph Schliemann; Dario Neri

368

Antigen-antibody binding kinetics for biosensors  

Microsoft Academic Search

The diffusion-limited binding kinetics of antigen in solution to antibody immobilized on a biosensor surface is analyzed within\\u000a a fractal framework. Changes in the fractal dimension, Df observed are in the same and in the reverse directions as the forward binding rate coefficientk. For example, an increase in the concentration of the isoenzyme human creatine kinase isoenzyme MB form (CK-MB)

Ajit Sadana; Aruna Beela Ram

1996-01-01

369

Prevalence of Toxoplasma gondii antibodies in dingoes.  

PubMed

Serum samples from 62 dingoes (Canis familiaris dingo) trapped in five areas of southeastern New South Wales, Australia were tested for antibodies to Toxoplasma gondii. Six (10%) of the dingoes had direct agglutination test titers for T. gondii of greater than or equal to 1:64, and four of these animals had T. gondii-specific IgM, suggesting recent exposure. PMID:2388361

Johnson, A M; Phillips, P; Jenkins, D

1990-07-01

370

Preclinical Safety Evaluation of Monoclonal Antibodies  

Microsoft Academic Search

Monoclonal antibodies (mAbs) are a well-established product class of biotechnology-derived pharmaceuticals for treating multiple\\u000a diseases. A growing number of mAbs are being tested in clinical trials worldwide. Many of the second generation mAbs entering\\u000a the clinic today are highly engineered, produced from recombinant cell lines, and present new safety challenges for regulators\\u000a and industry scientists responsible for their safety evaluation.

C. M. Lynch; I. S. Grewal

371

A new method for isolation of human antisperm antibodies.  

PubMed

A study was undertaken to isolate pure human antisperm antibodies from the sera of infertile couples. One hundred infertile couples attending the Infertility and IVF Unit (Beilinson Medical Center) because of unexplained infertility were tested (both partners) for antisperm antibodies. Sixty-eight experiments were performed with positive sera containing antisperm antibodies and normal donor sperm. These experiments were followed by experiments in order to elute pure human antisperm antibodies from the sperm surface. Three experiments were performed with human sperm which were found to be coated by antisperm antibodies, in order to directly elute these antibodies from the sperm surface. In all experiments we eluted antisperm antibodies of the IgG and IgA isotypes from the sperm surface. These antibodies were demonstrated in the eluate, in each case by either the indirect immunobead test, the radial immune diffusion assay, or the electrophoresis method. Control experiments were performed as follows: (i) normal donor sperm incubated with normal serum; (ii) normal donor sperm without serum incubation; (iii) normal donor lymphocytes incubated with serum containing antisperm antibodies; (iv) normal donor lymphocytes without serum incubation. No antisperm antibodies were obtained in any of these control experiments. Absorption and elution experiments can be used for the isolation of pure human antisperm antibodies, which may then be used for the production of anti-idiotypic antibodies to antisperm antibodies. The anti-idiotypic antibodies could be further utilized as antigen substitutes for the production of a contraceptive vaccine and/or for application in the treatment of spontaneous abortion and infertility. PMID:8893096

Shohat, M; Hardy, B; Mannheimer, S; Fisch, B; Shohat, B

1996-01-01

372

Antibody neutralization of retargeted measles viruses.  

PubMed

The measles virus (MV) vaccine lineage is a promising oncolytic but prior exposure to the measles vaccine or wild-type MV strains limits treatment utility due to the presence of anti-measles antibodies. MV entry can be redirected by displaying a polypeptide ligand on the Hemagglutinin (H) C-terminus. We hypothesized that retargeted MV would escape neutralization by monoclonal antibodies (mAbs) recognizing the H receptor-binding surface and be less susceptible to neutralization by human antisera. Using chimeric H proteins, with and without mutations that ablate MV receptor binding, we show that retargeted MVs escape mAbs that target the H receptor-binding surface by virtue of mutations that ablate infection via SLAM and CD46. However, C-terminally displayed domains do not mediate virus entry in the presence of human antibodies that bind to the underlying H domain. In conclusion, utility of retargeted oncolytic measles viruses does not extend to evasion of human serum neutralization. PMID:24725950

Lech, Patrycja J; Pappoe, Roland; Nakamura, Takafumi; Tobin, Gregory J; Nara, Peter L; Russell, Stephen J

2014-04-01

373

Complement in monoclonal antibody therapy of cancer.  

PubMed

Monoclonal antibodies (mAb) have been used as targeted treatments against cancer for more than a decade, with mixed results. Research is needed to understand mAb mechanisms of action with the goal of improving the efficacy of currently used mAbs and guiding the design of novel mAbs. While some mAb-induced tumor cell killing is a result of direct effects on tumor cell signaling, mAb opsonization of tumor cells also triggers activation of immune responses due to complement activation and engagement of antibody receptors on immune effector cells. In fact, complement has been shown to play an important role in modulating the anti-tumor activity of many mAb through complement-dependent cytotoxicity, antibody-dependent cytotoxicity, and through indirect effects by modulating the tumor microenvironment. Complement activity can have both agonistic and antagonistic effects on these processes. How the balance of such effects impacts on the clinical efficacy of mAb therapy remains unclear. In this review, we discuss the mAbs currently approved for cancer treatment and examine how complement can impact their efficacy with a focus on how this information might be used to improve the clinical efficacy of mAb treatment. PMID:24906530

Rogers, Laura M; Veeramani, Suresh; Weiner, George J

2014-08-01

374

In situ production of therapeutic monoclonal antibodies.  

PubMed

The use of antibodies as a treatment for disease has it origins in experiments performed in the 1890s, and since these initial experiments, monoclonal antibodies (mAbs) have become one of the fastest growing therapeutic classes for the treatment of cancer, autoimmune disease, and infectious diseases. However, treatment with therapeutic mAbs often requires high doses given via long infusions or multiple injections, which, coupled with the prohibitively high cost associated with the production of clinical-grade proteins and the transient serum half-lives that necessitate multiple administrations to gain therapeutic benefits, makes large-scale treatment of patients, especially patients in the developing world, difficult. Due to their low-cost and rapid scalability, nucleic acid-based approaches to deliver antibody gene sequences for in situ mAb production have gained substantial traction. In this review, we discuss new approaches to produce therapeutic mAbs in situ to overcome the need for the passive infusion of purified protein. PMID:25578347

Suscovich, Todd J; Alter, Galit

2015-02-01

375

Pseudomonas infection in antibody deficient patients  

PubMed Central

Pseudomonas aeruginosa (PA) is commonly isolated from the respiratory secretions of antibody deficiency patients, but the significance of this has not been well studied. We have reviewed our adult antibody deficiency cohort of 179 patients and assessed the prevalence and characteristics of PA infection and the effects of early antibiotic eradication treatments. Of the 34 patients with PA, 55.9% (19) underwent successful eradication and were infection-free, 38.2% (13) had intermittent infection, and 5.9% (2) had chronic PA. PA infection was significantly associated with bronchiectasis (p < 0.0001), with 36.1% (22 out of 61) of patients with bronchiectasis developing a PA infection. Infection status was also significantly associated with chronic sinusitis (p < 0.0001). Most treated PA exacerbations were symptomatic and with colony counts of ?1000 cfu/ml. Current eradication protocols used at our center involve early treatment at first positive isolate with ciprofloxacin for 3 weeks and nebulized colomycin for 3 months, and if eradication fails, intravenous ceftazidime and gentamycin or colomycin is administered for 2 weeks. Continued sputum surveillance and early eradication treatments upon positive PA culture may help to limit chronic PA infection in antibody deficiency patients.

Duraisingham, Sai S.; Hanson, Steven; Buckland, Matthew; Grigoriadou, Sofia

2014-01-01

376

[Acute pandysautonomia and nicotinic acetylcholine receptor antibodies].  

PubMed

Acute pandysautonomia is an idiopathic, acute or subacute autonomic neuropathy, which diffusely affects pre- and post-synaptic, and sympathetic and parasympathetic nerves. The recent discovery of serum autoantibodies against the nicotinic acethylcholine receptor (nAChR) on autonomic ganglia has led to a better understanding of its pathogenesis as well as the emergence of a new disease entity named autoimmune autonomic ganglionopathy (AAG). Based on the detection of these antibodies in various dysautonomic conditions, AAG is considered a broad-spectrum disease entity that includes acute pandysautonomia as well as secondary autonomic neuropathy, restricted forms of dysautonomia (postural tachycardia syndrome and chronic intestinal pseudoobstruction), and chronic dysautonomia, mimicking pure autonomic failure. Reproduction of experimental AAG animals by active immunization with peptides derived from ganglionic nAChR or passive transfer of ganglionic nAChR antibodies strongly indicates that ganglionic nAChR antibodies are pathogenic in AAG development. There are no controlled treatment trials for AAG, and its optimal therapy remains uncertain. Recent reports suggest that combined immunotherapies using immunosuppressive agents with plasma exchange or intravenous immunoglobulin are effective for some intractable cases. An optimal protocol of combined immunotherapies should be established in controlled clinical trials in the future. PMID:23568990

Koga, Michiaki

2013-04-01

377

ADME of antibody-maytansinoid conjugates.  

PubMed

The concept of treating cancer with antibody-drug conjugates (ADCs) has gained momentum with the favorable activity and safety of trastuzumab emtansine (T-DM1), SAR3419, and lorvotuzumab mertansine (IMGN901). All three ADCs utilize maytansinoid cell-killing agents which target tubulin and suppress microtubule dynamics. Each ADC utilizes a different optimized chemical linker to attach the maytansinoid to the antibody. Characterizing the absorption, distribution, metabolism, and excretion (ADME) of these ADCs in preclinical animal models is important to understanding their efficacy and safety profiles. The ADME properties of these ADCs in rodents were inferred from studies with radio-labeled ADCs prepared with nonbinding antibodies since T-DM1, SAR3419, IMGN901 all lack cross-reactivity with rodent antigens. For studies exploring tumor localization and activation in tumor-bearing mice, tritium-labeled T-DM1, SAR3419, and IMGN901 were utilized. The chemical nature of the linker was found to have a significant impact on the ADME properties of these ADCs-particularly on the plasma pharmacokinetics and observed catabolites in tumor and liver tissues. Despite these differences, T-DM1, SAR3419, and IMGN901 were all found to facilitate efficient deliveries of active maytansinoid catabolites to the tumor tissue in mouse xenograft models. In addition, all three ADCs were effectively detoxified during hepatobiliary elimination in rodents. PMID:22875610

Erickson, Hans K; Lambert, John M

2012-12-01

378

Polyclonal antibody to soman-tyrosine  

PubMed Central

Soman forms a stable, covalent bond with tyrosine 411 of human albumin, with tyrosines 257 and 593 in human transferrin, and with tyrosine in many other proteins. The pinacolyl group of soman is retained, suggesting that pinacolyl methylphosphonate bound to tyrosine could generate specific antibodies. Tyrosine in the pentapeptide RYGRK was covalently modified with soman simply by adding soman to the peptide. The phosphonylated-peptide was linked to keyhole limpet hemocyanin, and the conjugate was injected into rabbits. The polyclonal antiserum recognized soman-labeled human albumin, soman-mouse albumin, and soman human transferrin, but not non-phosphonylated control proteins. The soman-labeled tyrosines in these proteins are surrounded by different amino acid sequences, suggesting that the polyclonal recognizes soman-tyrosine independent of the amino acid sequence. Antiserum obtained after 4 antigen injections over a period of 18 weeks was tested in a competition ELISA where it had an IC50 of 10?11 M. The limit of detection on Western blots was 0.01 ?g (15 picomoles) of soman-labeled albumin. In conclusion, a high-affinity, polyclonal antibody that specifically recognizes soman adducts on tyrosine in a variety of proteins has been produced. Such an antibody could be useful for identifying secondary targets of soman toxicity. PMID:23469927

Li, Bin; Duysen, Ellen G.; Froment, Marie-Thérčse; Masson, Patrick; Nachon, Florian; Jiang, Wei; Schopfer, Lawrence M.; Thiele, Geoffrey M.; Klassen, Lynell W.; Cashman, John; Williams, Gareth R.; Lockridge, Oksana

2013-01-01

379

Kinetics of antibody production by single cells  

PubMed Central

The primary antibody response of the IgM type against sheep red blood cells, by spleen cells obtained from mice immunized in vivo has been studied at the cellular level. The modified plaque assay technique which was used allows the quantitative recording of plaque formation and growth in a carboxymethylcellulose gel. The distribution of plaque size at different times of incubation indicates that the secretion rate and the final amount of antibody released differ considerably between individual PFC of the same splenic population. However, the mean sizes of plaques from splenic populations at the same time after immunization are similar from mouse to mouse. During in vitro incubation, the kinetics of plaque growth display characteristic features, thus differentiating PFC populations from mice examined at different times after in vivo immunization. Most notably, there is a decrease in the mean size of the plaques between day 4 and day 5 following immunization. These results are discussed in terms of antibody secretion by PFC populations during the primary response. ImagesFIG. 2 PMID:4554744

Weyer, J.; Bourgarit, J. J.; Bussard, A. E.

1972-01-01

380

IgE antibodies in toxoplasmosis.  

PubMed

Toxoplasmosis is a worldwide infection caused by the intracellular parasite Toxoplasma gondii. At least a third of the world human population is infected with the parasite, making it one of the most successful parasitic infections. Primary maternal infection may cause health-threatening sequelae for the fetus, or even cause death of the uterus. Reactivation of a latent infection in immune deficiency conditions such as AIDS and organ transplantation can cause fatal toxoplasmic encephalitis. Toxoplasmosis is a major cause of chorioretinitis, especially in individuals with impaired immune systems. In the acute phase, directly after invading the body, T. gondii begins to multiply rapidly. In the majority of cases acquired toxoplasmosis is asymptomatic. In the second week of infection, specific IgM antibodies are present in the blood. IgE antibodies appear at the same time, slightly preceding specific IgA antibodies. The concentration of IgE can be one of the parameters used for diagnosing an infection with T. gondii. Laboratory diagnosis, i.e. IgE and serologic assays, plays the main role in the diagnosis of congenital infection and assists in the confirmatory diagnosis of toxoplasmic encephalitis and ocular toxoplasmosis. This article is a review of IgE in toxoplasmosis. PMID:24864110

Matowicka-Karna, Joanna; Kemona, Halina

2014-01-01

381

Peptide antibodies and their use in detecting oncogene products  

SciTech Connect

A polyclonal antibody preparation is described. It binds selectively to a characteristic marker epitope encompassing amino acid position 12 of an activated form of p21 protein, wherein the polyclonal antibody preparation is specific for a particular polyclonal antibody amino acid at position 12 and does not bind the p21 protein encoded by the corresponding proto-oncogene. A method for detecting an activated form of p21 protein is also described. It is encoded by an oncogene in a cellular sample of a patient which protein has a characteristic marker epitope encompassing amino acid position 12 which is not present in the p21 protein encoded by the corresponding proto-oncogene and which is not exposed in the undenatured protein. The method comprises: (a) treating the sample with a protein denaturing agent that causes the epitope to be exposed and does not substantially inhibit binding of an antibody to the epitope of the protein, (b) incubating the sample with the antibody under conditions that permit the binding of the antibody preparation to the epitope, (c) incubating the sample with a labeled antibody which binds specifically to the antibody employed in step (b), (d) washing the incubated sample to remove unbound labeled antibody, and (e) detecting the presence of labelled immune complexes of the epitope with the antibodies employed in steps (b) and (c).

Wong, G.L.; Arnheim, N.; McCormick, F.P.; Wong, G.L.; Clark, R.; Arnheim, N.; Nitecki, D.E.

1989-01-17

382

Antibody-drug conjugates: the chemistry behind empowering antibodies to fight cancer.  

PubMed

For more than a century, the concept of a "magic bullet" to deliver cytotoxic therapy to the site of disease has been envisioned but only recently have technological advances enabled antibody-drug conjugates to fulfill that dream. The recent approvals of brentuximab vedotin and ado-trastuzumab emtansine and emerging data for many molecules in clinical trials highlight the potential for antibody-drug conjugates to offer new therapeutic options for patients. This chapter reviews the evolution, state of the art, and potential future improvements that are enabling rapid development of this important class of cancer therapeutics. PMID:24319196

Drachman, Jonathan G; Senter, Peter D

2013-01-01

383

IBC's 22nd Annual Antibody Engineering and 9th Annual Antibody Therapeutics International Conferences and the 2011 Annual Meeting of The Antibody Society, December 5-8, 2011, San Diego, CA.  

PubMed

The 22nd Annual Antibody Engineering and 9th Annual Antibody Therapeutics international conferences, and the 2011 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, were held December 5-8, 2011 in San Diego, CA. The meeting drew ~800 participants who attended sessions on a wide variety of topics relevant to antibody research and development. As a preview to the main events, a pre-conference workshop held on December 4, 2011 focused on antibodies as probes of structure. The Antibody Engineering Conference comprised eight sessions: (1) structure and dynamics of antibodies and their membrane receptor targets; (2) model-guided generation of binding sites; (3) novel selection strategies; (4) antibodies in a complex environment: targeting intracellular and misfolded proteins; (5) rational vaccine design; (6) viral retargeting with engineered binding molecules; (7) the biology behind potential blockbuster antibodies and (8) antibodies as signaling modifiers: where did we go right, and can we learn from success? The Antibody Therapeutics session comprised five sessions: (1)Twenty-five years of therapeutic antibodies: lessons learned and future challenges; (2) preclinical and early stage development of antibody therapeutics; (3) next generation anti-angiogenics; (4) updates of clinical stage antibody therapeutics and (5) antibody drug conjugates and bispecific antibodies. PMID:22453091

Nilvebrant, Johan; Dunlop, D Cameron; Sircar, Aroop; Wurch, Thierry; Falkowska, Emilia; Reichert, Janice M; Helguera, Gustavo; Piccione, Emily C; Brack, Simon; Berger, Sven

2012-01-01

384

Spectrum of antibodies to reproductive hormones in threatened abortion.  

PubMed

The spectrum of antibodies to reproductive hormones and the diagnostic significance of their measurements in threatened abortion during trimester I were studied. Enhanced production of antibodies to hormones was detected by ELISA in patients with threatened abortion (N=44) in comparison with women with normal gestation (N=30). These antibodies were detected more often than antiphospholipid antibodies (p<0.05). Antibodies to chorionic gonadotropin (IgM, IgG) and gonadotropin-releasing hormone (IgG) were associated with threatened abortion. According to ROC analysis, their measurements were diagnostically significant in this pathology (AUC>0.8). Subclasses IgG1 and IgG2 predominated among IgG to chorionic gonadotropin. Presumably, antibodies to chorionic gonadotropin and gonadotropin-releasing hormone could serve as independent factors of threatened abortion risk during trimester I. PMID:25348563

Menzhinskaya, I V; Van'ko, L V; Kiryushchenkov, P A; Tambovtseva, M A; Kashentseva, M M; Sukhikh, G T

2014-10-01

385

Generation of neutralising antibodies against porcine endogenous retroviruses (PERVs)  

SciTech Connect

Antibodies neutralising porcine endogenous retroviruses (PERVs) were induced in different animal species by immunisation with the transmembrane envelope protein p15E. These antibodies recognised epitopes, designated E1, in the fusion peptide proximal region (FPPR) of p15E, and E2 in the membrane proximal external region (MPER). E2 is localised in a position similar to that of an epitope in the transmembrane envelope protein gp41 of the human immunodeficiency virus-1 (HIV-1), recognised by the monoclonal antibody 4E10 that is broadly neutralising. To detect neutralising antibodies specific for PERV, a novel assay was developed, which is based on quantification of provirus integration by real-time PCR. In addition, for the first time, highly effective neutralising antibodies were obtained by immunisation with the surface envelope protein of PERV. These data indicate that neutralising antibodies can be induced by immunisation with both envelope proteins.

Kaulitz, Danny; Fiebig, Uwe; Eschricht, Magdalena; Wurzbacher, Christian; Kurth, Reinhard; Denner, Joachim, E-mail: DennerJ@rki.d

2011-03-01

386

Antibody Responses to Cryptococcus neoformans in Indian Patients with Cryptococcosis  

PubMed Central

SUMMARY An important element of the host response to cryptococcosis is humoral immunity. Specific antibody responses in patients with cryptococcosis however, have not been extensively studied. We analyzed the antibody responses of 22 Indian patients with cryptococcosis, including both HIV+ and HIV- individuals. Sera from 10 Indian patients with AIDS and without cryptococcosis were studied as controls. Antibody responses to cryptococcal proteins were detected by immunoblot, while antibodies to glucuronoxylomannan (GXM), the main component of the cryptococcal capsular polysaccharide were measured by ELISA. Our results indicate that cryptococcosis elicits antibodies to a specific pattern of cytoplasmic proteins. Further, we find that antibody responses to both cytoplasmic proteins and GXM are less robust in HIV+ patients when compared with HIV- patients. PMID:18608912

Saha, Dolan Champa; Xess, Immaculata; Zeng, Wang Yong; Goldman, David L.

2014-01-01

387

Antigen-Antibody Testing: A Visual Simulation or Virtual Reality  

NSDL National Science Digital Library

In this biology activity, learners use plastic pipettes to cut wells into the solid gel layer of agar in petri dishes and place solutions of simulated antigen and antibody preparations into the wells. The antigens and antibodies diffuse into the gel layer and react to form a precipitate. This activity demonstrates the biological phenomenon of the formation of a precipitate when an antigen reacts with an antibody. The exercise can be used to illustrate the specificity of antigen-antibody reactions, showing that a precipitation reaction only occurs when an antibody reacts with the antigen that was used to induce the formation of the antibody. The exercise is also a general demonstration of diffusion. Adult supervision is recommended.

Schadler, Daniel

2011-01-01

388

Anti-acetylcholinesterase antibodies display cholinesterase-like activity.  

PubMed

A monoclonal antibody (mAb) raised against human acetylcholinesterase (AChE) was found to have catalytic activity. A similar phenomenon was observed in a polyclonal antibody raised against the same antigen. The antibodies were demonstrated to be pure, and no contamination with either AChE or butyrylcholinesterase was found. Both antibodies hydrolyzed acetylthiocholine, an AChE substrate, and the mAb followed Michaelis-Menten kinetics. Six other mAb and one other polyclonal antibody showed no evidence of catalytic activity. This development of cholinesterase-like behavior by certain anti-AChE antibodies may have arisen by stable complexation of the enzyme with a substrate or inhibitor during antigen presentation. This phenomenon may have implications for the diagnostic measurement of AChE activity as well as in assessing the immunological reasons for the markedly raised AChE level in developmental conditions such as Hirschsprung's disease. PMID:7843238

Johnson, G; Moore, S W

1995-01-01

389

Shortened Engineered Human Antibody CH2 Domains  

PubMed Central

The immunoglobulin (Ig) constant CH2 domain is critical for antibody effector functions. Isolated CH2 domains are promising scaffolds for construction of libraries containing diverse binders that could also confer some effector functions. We have shown previously that an isolated human CH2 domain is relatively unstable to thermally induced unfolding, but its stability can be improved by engineering an additional disulfide bond (Gong, R., Vu, B. K., Feng, Y., Prieto, D. A., Dyba, M. A., Walsh, J. D., Prabakaran, P., Veenstra, T. D., Tarasov, S. G., Ishima, R., and Dimitrov, D. S. (2009) J. Biol. Chem. 284, 14203–14210). We have hypothesized that the stability of this engineered antibody domain could be further increased by removing unstructured residues. To test our hypothesis, we removed the seven N-terminal residues that are in a random coil as suggested by our analysis of the isolated CH2 crystal structure and NMR data. The resulting shortened engineered CH2 (m01s) was highly soluble, monomeric, and remarkably stable, with a melting temperature (Tm) of 82.6 °C, which is about 10 and 30 °C higher than those of the original stabilized CH2 (m01) and CH2, respectively. m01s and m01 were more resistant to protease digestion than CH2. A newly identified anti-CH2 antibody that recognizes a conformational epitope bound to m01s significantly better (>10-fold higher affinity) than to CH2 and slightly better than to m01. m01s bound to a recombinant soluble human neonatal Fc receptor at pH 6.0 more strongly than CH2. These data suggest that shortening the m01 N terminus significantly increases stability without disrupting its conformation and that our approach for increasing stability and decreasing size by removing unstructured regions may also apply to other proteins. PMID:21669873

Gong, Rui; Wang, Yanping; Feng, Yang; Zhao, Qi; Dimitrov, Dimiter S.

2011-01-01

390

Leukocyte analysis using monoclonal antibodies in human glomerulonephritis  

Microsoft Academic Search

Leukocyte analysis using monoclonal antibodies in human glomerulonephritis. The leukocyte subpopulations were analyzed within both the glomeruli and the interstitium in renal biopsies from 145 patients with various forms of glomerulonephritis. Cells were identified by monoclonal antibodies to leukocyte cell–surface antigens and immunoper-oxidase labelling. Leukocytes, as defined by a monoclonal antibody to the leukocyte common antigen (PHM1), were present in

David H Hooke; David C Gee; Robert C Atkins

1987-01-01

391

Therapeutic potential of anti-IgE antibodies  

Microsoft Academic Search

Anti-IgE antibodies directed against the Fc?RI-binding region on IgE inhibit binding of IgE to IgE receptors without inducing mediator release from IgE sensitized cells. In mice these antibodies selectively reduce serum IgE, inhibit antigen induced skin reactions, cytokine production by lung Th2 cells, and pulmonary eosinophil infiltration. Clinical trials in humans reveal that such antibodies are well tolerated and reduce

Christoph Heusser; Paula Jardieu

1997-01-01

392

Antibodies to Canine Helminth Parasites in Asthmatic and Nonasthmatic Children  

Microsoft Academic Search

We studied the prevalence of IgE and IgG antibodies to Toxocara canis and Dirojilaria immitis, helminth parasites of dogs, in asthmatic and nonasthmatic children born and raised in Hawaii. The serologic pattern of the two groups was found to differ significantly. Of the 80 asthmatic subjects, 45.0% had IgE antibody and 17.5% IgG-precipitating antibody to one or both parasites. In

Robert S. Desowitz; Raoul Rudoy; John W. Barnwell

1981-01-01

393

Efficient heterodimerization of recombinant bi- and trispecific antibodies  

Microsoft Academic Search

Bispecific antibodies (BsAb) are promising therapeutic tools in tomorrow's medicine. Expression systems favoring efficient heterodimerization of intermediate-sized bispecific antibodies will significantly improve existing production methods. By C-terminal fusion of scFv molecules to the Fd- and the L-chains efficient heterodimerization in mammalian cells was obtained and a novel intermediate sized, disulfide stabilized BsAb could be efficiently produced. This type of antibody

R. Schoonjans; A. Willems; J. Grooten; N. Mertens

2000-01-01

394

Identification of Pigment Cell Antigens Defined by Vitiligo Antibodies  

Microsoft Academic Search

Patients with vitiligo have circulating antibodies to pigment cells. To characterize this response further and to identify the antigens defined by vitiligo antibodies, sera of 23 patients with vitiligo and 22 patients with unrelated conditions were analyzed by immunoprecipitation and SDS-PAGE analysis of 125I-labeled cell antigens on pigment and control cells. Antibodies to pigment cell antigens were present in 18

Jian Cui; Ronald Harning; Milagros Henn; Jean-Claude Bystryn

1992-01-01

395

Monoclonal Antibodies That Recognize Discrete Forms of Tubulin  

Microsoft Academic Search

Anti-tubulin antibodies secreted by plasmacytoma NSI-spleen cell hybrids were detected by an indirect binding assay. Different antibodies bound to different combinations of the tubulins as resolved by isoelectric focusing. Two monoclonal antibodies (TUB 2.1 and TUB 2.5) labeled only (i) the tubulin band on a polyacrylamide electropherogram and (ii) beta -tubulins as resolved by isoelectric focusing. The fraction that was

Illana Gozes; Colin J. Barnstable

1982-01-01

396

Monoclonal antibodies to plant plasma-membrane antigens  

Microsoft Academic Search

Murine monoclonal antibodies to membrane antigens were generated by immunization with a crude cellular membrane preparation from suspension-cultured cells of Nicotiana glutinosa L. From a panel of thirteen monoclonal antibodies, seven were found to be directed against antigens present on the plasma-membrane by immunofluorescence visualization of antibody binding to the surface of isolated protoplasts. The corresponding set of plasma-membrane antigen(s)

P. M. Norman; V. P. M. Wingate; M. S. Fitter; C. J. Lamb

1986-01-01

397

Antibodies to carbonic anhydrase in patients with immune cholangiopathies  

Microsoft Academic Search

Background\\/Aims: Bile duct epithelia contain an abundance of carbonic anhydrase. Antibodies to this enzyme have been described in autoimmune disorders. Serum from patients with immune-mediated liver diseases was studied to determine whether antibodies to carbonic anhydrase II and\\/or pyruvate dehydrogenase could distinguish autoimmune cholangitis as immunologically distinct from primary biliary cirrhosis. Methods: Antibody assays to carbonic anhydrase II (Western blot)

Stuart C. Gordon; Therese M. Quattrociocchi-Longe; Bilal A. Khan; Valli P. Kodali; Jenn Chen; Ann L. Silverman; Frederick L. Kiechle

1995-01-01

398

Principles and engineering of antibody folding and assembly.  

PubMed

Antibodies are uniquely suited to serve essential roles in the human immune defense as they combine several specific functions in one hetero-oligomeric protein. Their constant regions activate effector functions and their variable domains provide a stable framework that allows incorporation of highly diverse loop sequences. The combination of non-germline DNA recombination and mutation together with heavy and light chain assembly allows developing variable regions that specifically recognize essentially any antigen they may encounter. However, this diversity also requires tailor-made mechanisms to guarantee that folding and association of antibodies is carefully this diversity also requires tailor-made mechanisms to guarantee that folding and association of antibodies is carefully controlled before the protein is secreted from a plasma cell. Accordingly, the generic immunoglobulin fold ?-barrel structure of antibody domains has been fine-tuned during evolution to fit the different requirements. Work over the past decades has identified important aspects of the folding and assembly of antibody domains and chains revealing domain specific variations of a general scheme. The most striking is the folding of an intrinsically disordered antibody domain in the context of its partner domain as the basis for antibody assembly and its control on the molecular level in the cell. These insights have not only allowed a better understanding of the antibody folding process but also provide a wealth of opportunities for rational optimization of antibody molecules. In this review, we summarize current concepts of antibody folding and assembly and discuss how they can be utilized to engineer antibodies with improved performance for different applications. This article is part of a Special Issue entitled: Recent advances in the molecular engineering of antibodies. PMID:24931831

Feige, Matthias J; Buchner, Johannes

2014-11-01

399

A Humanized Antibody that Binds to the Interleukin 2 Receptor  

Microsoft Academic Search

The anti-Tac monoclonal antibody is known to bind to the p55 chain of the human interleukin 2 receptor and to inhibit proliferation of T cells by blocking interleukin 2 binding. However, use of anti-Tac as an immunosuppressant drug would be impaired by the human immune response against this murine antibody. We have therefore constructed a ``humanized'' antibody by combining the

Cary Queen; William P. Schneider; Harold E. Selick; Philip W. Payne; Nicholas F. Landolfi; James F. Duncan; Nevenka M. Avdalovic; Michael Levitt; Richard P. Junghans; Thomas A. Waldmann

1989-01-01

400

Commercial antibodies: the good, bad, and really ugly.  

PubMed

The range of antibodies available commercially grows ever larger. Perhaps as a consequence, quality control is not always what it could and should be. Investigators must be aware of potential pitfalls and take steps to assure themselves that the specificity of each antibody is as advertised. Additionally, companies should provide the necessary information about the antigen and antibody to investigators, including references, so that the appropriate controls can be included. PMID:18854593

Couchman, John R

2009-01-01

401

Binding kinetics of immobilized antibodies in a flow immunosensor  

Microsoft Academic Search

This study investigates the binding kinetics of immobilized antibody in a solid-phase displacement immunosensor conducted in flow under nonequuilibrium conditions. The experimental system studied employs a monoclonal antibody, specific for cocaine and its metabolite, benzoylecgonine, immobilized onto agarose beads. After saturation of antibody binding sites with the fluorophore-induced antigen, fluorescein-cadaverine-benzoylecgonine, the system is placed in a buffer flow. Injection of

Sina Y. Rabbany; Anne W. Kusterbeck; Reinhard Bredehorst; Frances S. Ligler

1995-01-01

402

Application for Antigen—Antibody Sensor Using Carbon Nanotubes  

NASA Astrophysics Data System (ADS)

An antigen-antibody sensor consisting of a silicon-based chip contains a mixture of poly [ethylene glycol] (PEG)-grafted carbon nanotubes (PEG-CNTs) and CNTs modified with an antigen by using plasma ion irradiation (plasma activation) method, is developed. According to result of experiments, impedance increased due to antigen/antibody reaction. The results indicate that this antigen-antibody sensor could react until 10 g/ml antigen density.

Funada, Yuichiro; Hirata, Takamichi; Akiya, Masahiro

403

Antibody titers predict clinical features of autoimmune autonomic ganglionopathy.  

PubMed

Autoimmune autonomic ganglionopathy is a disorder of isolated autonomic failure associated with antibodies to the nicotinic acetylcholine receptor of the autonomic ganglia resulting in severe orthostatic intolerance, syncope, constipation, gastroparesis, urinary retention, dry mouth, dry eyes, blurred vision and anhidrosis. We report the autonomic test results, antibody titers and clinical findings in 8 patients with antibodies to the nicotinic acetylcholine receptor of the autonomic ganglia. There was a sigmoidal relation between the antibody titers and the fall in systolic blood pressure (r(2)=0.84). The threshold occurred with antibody titers of approximately 1 nmol/l. Over the linear portion of the sigmoid curve, with antibody titers in the 1-3 nmol/l range, increasing antibody titers resulted in more severe orthostatic hypotension (r=0.94, P<0.001). The saturation point of the sigmoidal relation occurred at approximately 3 nmol/l with drops in systolic blood pressure of approximately 100 mmHg during upright tilt. The antibody titers correlated inversely with the Valsalva ratio (r=-0.87, P<0.001), the 30:15 ratio (r=-0.84, P<0.001) and the expiratory to inspiratory ratio (r=-0.67, P<0.01). Patients with orthostatic intolerance, anhidrosis, constipation, urinary dysfunction, sicca syndrome and pupillary dysfunction had higher antibody titers than subjects that did not (P<0.01 in all cases). Autoimmune autonomic ganglionopathy is a clinically heterogeneous disease with variable presentation, particularly in subjects with lower antibody titers. Our data suggest that patients with higher antibody titers have wide spread dysautonomia while those with lower antibody levels may present with, or evolve into, more focal or restricted presentations. PMID:19144572

Gibbons, Christopher H; Freeman, Roy

2009-03-12

404

Antibody testing as a diagnostic tool in autonomic disorders  

Microsoft Academic Search

Some forms of peripheral autonomic dysfunction (especially enteric neuropathy and subacute panautonomic failure) occur as\\u000a autoimmune phenomena either in isolation or in the context of cancer. Autoimmune autonomic ganglionopathy is an example of\\u000a a severe, but potentially treatable, antibody-mediated form of autonomic failure. Diagnostic evaluation of autonomic disorders\\u000a can be supplemented by testing for paraneoplastic antibodies and antibodies against membrane

Steven Vernino

2009-01-01

405

Antibody-based therapeutics: Focus on prostate cancer  

Microsoft Academic Search

Summary  The recent clinical and commercial success of anti-cancer antibodies such as rituximab, trastuzumab, cetuximab and bevacizumab\\u000a has continued to foster great interest in antibody-based therapeutics for the treatment of both hematopoietic malignancies\\u000a and solid tumors. Given the likely lower toxicity for antibodies which, in contrast with traditional cytotoxic small molecule\\u000a drugs, target tumor cells and have a lower impact on

Jeffrey S. Ross; Karen E. Gray; Iain J. Webb; Gary S. Gray; Mark Rolfe; David P. Schenkein; David M. Nanus; Mathew I. Millowsky; Neil H. Bander

2005-01-01

406

PRODUCTION AND CHARACTERIZATION OF MONOCLONAL ANTIBODIES, APTAMERS AND SINGLE CHAIN ANTIBODIES TO MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Paratuberculosis (MAP) was identified as an unmet need at the 7th International Colloquium on Paratuberculosis in Bilbao, Spain. To fill this gap in Johne’s disease research, monoclonal antibodies (mAbs) against MAP were produced from BALB/c mice immunized with sonicated MAP extracts or recombinant...

407

Selection and identification of single domain antibody fragments from camel heavy-chain antibodies  

Microsoft Academic Search

Functional heavy-chain ?-immunoglobulins lacking light chains occur naturally in Camelidae. We now show the feasibility of immunising a dromedary, cloning the repertoire of the variable domains of its heavy-chain antibodies and panning, leading to the successful identification of minimum sized antigen binders. The recombinant binders are expressed well in E. coli, extremely stable, highly soluble, and react specifically and with

M Arbabi Ghahroudi; A Desmyter; L Wyns; R Hamers; S Muyldermans

1997-01-01

408

Mechanisms of Allergen-Antibody Interaction of Cockroach Allergen Bla g 2 with Monoclonal Antibodies  

E-print Network

Mechanisms of Allergen-Antibody Interaction of Cockroach Allergen Bla g 2 with Monoclonal of Molecular Biology, University of Salzburg, Salzburg, Austria Abstract Background: Cockroach allergy-ray crystallography on opposite sites of the quasi-symmetrical cockroach allergen Bla g 2. Methodology

409

An Insertion Mutation That Distorts Antibody Binding Site Architecture Enhances Function of a Human Antibody  

SciTech Connect

The structural and functional significance of somatic insertions and deletions in antibody chains is unclear. Here, we demonstrate that a naturally occurring three-amino-acid insertion within the influenza virus-specific human monoclonal antibody 2D1 heavy-chain variable region reconfigures the antibody-combining site and contributes to its high potency against the 1918 and 2009 pandemic H1N1 influenza viruses. The insertion arose through a series of events, including a somatic point mutation in a predicted hot-spot motif, introduction of a new hot-spot motif, a molecular duplication due to polymerase slippage, a deletion due to misalignment, and additional somatic point mutations. Atomic resolution structures of the wild-type antibody and a variant in which the insertion was removed revealed that the three-amino-acid insertion near the base of heavy-chain complementarity-determining region (CDR) H2 resulted in a bulge in that loop. This enlarged CDR H2 loop impinges on adjacent regions, causing distortion of the CDR H1 architecture and its displacement away from the antigen-combining site. Removal of the insertion restores the canonical structure of CDR H1 and CDR H2, but binding, neutralization activity, and in vivo activity were reduced markedly because of steric conflict of CDR H1 with the hemagglutinin antigen.

Krause, Jens C.; Ekiert, Damian C.; Tumpey, Terrence M.; Smith, Patricia B.; Wilson, Ian A.; Crowe, Jr., James E. (Vanderbilt); (Scripps); (CDC)

2011-09-02

410

Commercially available angiotensin II At? receptor antibodies are nonspecific.  

PubMed

Commercially available angiotensin II At? receptor antibodies are widely employed for receptor localization and quantification, but they have not been adequately validated. In this study, we characterized three commercially available At? receptor antibodies: 2818-1 from Epitomics, sc-9040 from Santa Cruz Biotechnology, Inc., and AAR-012 from Alomone Labs. Using western blot analysis the immunostaining patterns observed were different for every antibody tested, and in most cases consisted of multiple immunoreactive bands. Identical immunoreactive patterns were present in wild-type and At? receptor knockout mice not expressing the target protein. In the mouse brain, immunocytochemical studies revealed very different cellular immunoreactivity for each antibody tested. While the 2818-1 antibody reacted only with endothelial cells in small parenchymal arteries, the sc-9040 antibody reacted only with ependymal cells lining the cerebral ventricles, and the AAR-012 antibody reacted only with multiple neuronal cell bodies in the cerebral cortex. Moreover, the immunoreactivities were identical in brain tissue from wild-type or At? receptor knockout mice. Furthermore, in both mice and rat tissue extracts, there was no correlation between the observed immunoreactivity and the presence or absence of At? receptor binding or gene expression. We conclude that none of these commercially available At? receptor antibodies tested met the criteria for specificity. In the absence of full antibody characterization, competitive radioligand binding and determination of mRNA expression remain the only reliable approaches to study At? receptor expression. PMID:23840911

Hafko, Roman; Villapol, Sonia; Nostramo, Regina; Symes, Aviva; Sabban, Esther L; Inagami, Tadashi; Saavedra, Juan M

2013-01-01

411

Commercially Available Angiotensin II At2 Receptor Antibodies Are Nonspecific  

PubMed Central

Commercially available angiotensin II AT2 receptor antibodies are widely employed for receptor localization and quantification, but they have not been adequately validated. In this study, we characterized three commercially available AT2 receptor antibodies: 2818-1 from Epitomics, sc-9040 from Santa Cruz Biotechnology, Inc., and AAR-012 from Alomone Labs. Using western blot analysis the immunostaining patterns observed were different for every antibody tested, and in most cases consisted of multiple immunoreactive bands. Identical immunoreactive patterns were present in wild-type and AT2 receptor knockout mice not expressing the target protein. In the mouse brain, immunocytochemical studies revealed very different cellular immunoreactivity for each antibody tested. While the 2818-1 antibody reacted only with endothelial cells in small parenchymal arteries, the sc-9040 antibody reacted only with ependymal cells lining the cerebral ventricles, and the AAR-012 antibody reacted only with multiple neuronal cell bodies in the cerebral cortex. Moreover, the immunoreactivities were identical in brain tissue from wild-type or AT2 receptor knockout mice. Furthermore, in both mice and rat tissue extracts, there was no correlation between the observed immunoreactivity and the presence or absence of AT2 receptor binding or gene expression. We conclude that none of these commercially available AT2 receptor antibodies tested met the criteria for specificity. In the absence of full antibody characterization, competitive radioligand binding and determination of mRNA expression remain the only reliable approaches to study AT2 receptor expression. PMID:23840911

Hafko, Roman; Villapol, Sonia; Nostramo, Regina; Symes, Aviva; Sabban, Esther L.; Inagami, Tadashi; Saavedra, Juan M.

2013-01-01

412

Influenza A Neuraminidase Antibody Assay with Sensitized Erythrocytes  

PubMed Central

Erythrocytes sensitized with purified neuraminidase (Hong Kong) antigens were used for assay of influenza A neuraminidase antibodies. The neuraminidase indirect hemagglutination test was equal to the neuraminidase hemagglutination-inhibition (enhancement) test and appeared to be better than the neuraminidase inhibition test for detection of fourfold or greater antibody rises in paired sera from influenza patients or vaccinees. It was better than both tests for detection of neuraminidase antibody. The neuraminidase indirect hemagglutination test is simple to perform and has the advantage of direct antigen-antibody assay. PMID:4631440

Holston, J. L.; Dowdle, W. R.

1973-01-01

413

2nd PEGS Annual Symposium on Antibodies for Cancer Therapy  

PubMed Central

The 2nd Annual Antibodies for Cancer Therapy symposium, organized again by Cambridge Healthtech Institute as part of the Protein Engineering Summit, was held in Boston, USA from April 30th to May 1st, 2012. Since the approval of the first cancer antibody therapeutic, rituximab, fifteen years ago, eleven have been approved for cancer therapy, although one, gemtuzumab ozogamicin, was withdrawn from the market.  The first day of the symposium started with a historical review of early work for lymphomas and leukemias and the evolution from murine to human antibodies. The symposium discussed the current status and future perspectives of therapeutic antibodies in the biology of immunoglobulin, emerging research on biosimilars and biobetters, and engineering bispecific antibodies and antibody-drug conjugates. The tumor penetration session was focused on the understanding of antibody therapy using ex vivo tumor spheroids and the development of novel agents targeting epithelial junctions in solid tumors. The second day of the symposium discussed the development of new generation recombinant immunotoxins with low immunogenicity, construction of chimeric antigen receptors, and the proof-of-concept of ‘photoimmunotherapy’. The preclinical and clinical session presented antibodies targeting Notch signaling and chemokine receptors.  Finally, the symposium discussed emerging technologies and platforms for therapeutic antibody discovery. PMID:22864478

Ho, Mitchell; Royston, Ivor; Beck, Alain

2012-01-01

414

Selection of phage antibodies to surface epitopes of Phytophthora infestans.  

PubMed

Antibodies specific for surface-exposed epitopes on germlings of the plant pathogen, Phytophthora infestans, were isolated from a diverse phage library displaying single-chain Fv (scFv) antibody fragments. The library was subpanned against external soluble components released from mycelia, sporangia and germlings and a discrete population of phage antibodies isolated. Binding of monoclonal phage antibodies was demonstrated by enzyme-linked immunosorbent assay (ELISA) and diversity was established by BstNI restriction enzyme digest patterns. Antibodies were subcloned as fusions at the C-terminus of maltose binding protein (MBP) and expressed as soluble proteins in Escherichia coli. These antibody fusion proteins bound to P. infestans germlings and to mycelial homogenates from various Phytophthora species. The binding activities to mycelial homogenates of fungal species not belonging to the order Peronosporales were substantially lower. Several phage-displayed scFvs were used in conjunction with fluorescently labelled antiphage antibody to visualise the distribution of their cognate epitopes on the surface of the germlings. The combination of procedures developed here with Phytophthora demonstrates the potential of phage antibody technology in isolating antibodies to cell surface and external soluble components of pathogens, some of which may play a role in host/pathogen interactions. PMID:10556547

Gough, K C; Li, Y; Vaughan, T J; Williams, A J; Cockburn, W; Whitelam, G C

1999-08-31

415

Modern Technologies for Creating Synthetic Antibodies for Clinical application  

PubMed Central

The modular structure and versatility of antibodies enables one to modify natural immunoglobulins in different ways for various clinical applications. Rational design and molecular engineering make it possible to directionally modify the molecular size, affinity, specificity, and immunogenicity and effector functions of an antibody, as well as to combine them with other functional agents. This review focuses on up-to-date methods of antibody engineering for diagnosing and treating various diseases, particularly on new technologies meant to refine the effector functions of therapeutic antibodies. PMID:22649585

Lebedenko, E. N.

2009-01-01

416

Molecularly defined antibody conjugation through a selenocysteine interface†  

PubMed Central

Antibody conjugates have broad utility in basic, preclinical, and clinical applications. Conventional antibody conjugation through the amine group of lysine or the thiol group of cysteine residues yields heterogeneous products of undefined stoichiometry and considerable batch-to-batch variability. To preserve the two hallmarks of the antibody molecule, precision and predictability, methods that enable site-specific antibody conjugation are in high demand. Based on a mammalian cell expression system, we describe the utilization of the 21st natural amino acid selenocysteine for the generation of IgG and Fab molecules with unique nucleophilic reactivity that affords site-specific conjugation to electrophilic derivatives of biotin, fluorescein, and poly(ethylene glycol). The resulting antibody conjugates were found to fully retain their antigen binding capability and, in case of IgG, the ability to mediate effector functions. Gain-of-function was demonstrated in vitro and in vivo. While these antibody conjugates are relevant for a variety of proteomic, diagnostic, and therapeutic applications, they also constitute a proof-of-principle for the generation of molecularly defined antibody-drug conjugates and radioimmunoconjugates. Compared to other site-specific antibody conjugation methods, selenocysteine interface technology (i) only involves a minor modification at the C-terminus that does not interfere with disulfide bridges, (ii) does not require activation, and (iii) generates unique 1:1 stoichiometries of biological and chemical component. Collectively, our method affords the generation of highly defined antibody conjugates with broad utility from proteomic applications to therapeutic intervention. PMID:19894757

Hofer, Thomas; Skeffington, Lauren R.; Chapman, Colby M.; Rader, Christoph

2009-01-01

417

Mechanisms of monoclonal antibody stabilization and release from silk biomaterials  

PubMed Central

The availability of stabilization and sustained delivery systems for antibody therapeutics remains a major clinical challenge, despite the growing development of antibodies for a wide range of therapeutic applications due to their specificity and efficacy. A mechanistic understanding of protein-matrix interactions is critical for the development of such systems and is currently lacking as a mode to guide the field. We report mechanistic insight to address this need by using well-defined matrices based on silk gels, in combination with a monoclonal antibody. Variables including antibody loading, matrix density, charge interactions, hydrophobicity and water access were assessed to clarify mechanisms involved in the release of antibody from the biomaterial matrix. The results indicate that antibody release is primarily governed by hydrophobic interactions and hydration resistance, which are controlled by silk matrix chemistry, peptide domain distribution and protein density. Secondary ionic repulsions are also critical in antibody stabilization and release. Matrix modification by free methionine incorporation was found to be an effective strategy for mitigating encapsulation induced antibody oxidation. Additionally, these studies highlight a characterization approach to improve the understanding and development of other protein sustained delivery systems, with broad applicability to the rapidly developing monoclonal antibody field. PMID:23859659

Guziewicz, Nicholas A.; Massetti, Andrew J.; Perez-Ramirez, Bernardo J.; Kaplan, David L.

2013-01-01

418

Derivatized gold clusters and antibody-gold cluster conjugates  

DOEpatents

Antibody- or antibody fragment-gold cluster conjugates are shown wherein the conjugate size can be as small as 5.0 nm. Methods and reagents are disclosed in which antibodies, Fab' or F(ab').sub.2 fragments thereof are covalently bound to a stable cluster of gold atoms. The gold clusters may contain 6, 8, 9, 11, 13, 55 or 67 gold atoms in their inner core. The clusters may also contain radioactive gold. The antibody-cluster conjugates are useful in electron microscopy applications as well as in clinical applications that include imaging, diagnosis and therapy.

Hainfeld, James F. (Shoreham, NY); Furuya, Frederic R. (Williston Park, NY)

1994-11-01

419

Derivatized gold clusters and antibody-gold cluster conjugates  

DOEpatents

Antibody- or antibody fragment-gold cluster conjugates are shown wherein the conjugate size can be as small as 5.0 nm. Methods and reagents are disclosed in which antibodies, Fab' or F(ab')[sub 2] fragments are covalently bound to a stable cluster of gold atoms. The gold clusters may contain 6, 8, 9, 11, 13, 55 or 67 gold atoms in their inner core. The clusters may also contain radioactive gold. The antibody-cluster conjugates are useful in electron microscopy applications as well as in clinical applications that include imaging, diagnosis and therapy. 7 figs.

Hainfeld, J.F.; Furuya, F.R.

1994-11-01

420

Cell adhesion molecules: detection with univalent second antibody  

PubMed Central

Identification of cell surface molecules that play a role in cell-cell adhesion (here called cell adhesion molecules) has been achieved by demonstrating the inhibitory effect of univalent antibodies that bind these molecules in an in vitro assay of cell-cell adhesion. A more convenient reagent, intact (divalent) antibody, has been avoided because it might agglutinate the cells rather than blocking cell-cell adhesion. In this report, we show that intact rabbit immunoglobulin directed against certain cell surface molecules of Dictyostelium discoideum blocks cell-cell adhesion when the in vitro assay is performed in the presence of univalent goat anti-rabbit antibody. Under appropriate experimental conditions, the univalent second antibody blocks agglutination induced by the rabbit antibody without significantly interfering with its effect on cell-cell adhesion. This method promises to be useful for screening monoclonal antibodies raised against potential cell adhesion molecules because: (a) it allows for the screening of large numbers of antibody samples without preparation of univalent fragments; and (b) it requires much less antibody because of the greater affinity of divalent antibodies for antigens. PMID:6970200

1980-01-01

421

Antiplatelet antibodies in oxaliplatin-induced immune thrombocytopenia  

PubMed Central

Lesson Drug-induced immune thrombocytopenia may be potentially fatal; here we report the development of severe thrombocytopenia with strong oxaliplatin-dependent antiplatelet antibodies. PMID:25057402

McNamara, Michael J; Curtis, Brian R; McCrae, Keith R

2014-01-01

422

Chimeric antibodies with extended half-life in ferrets  

PubMed Central

Background Ferrets have long been used as a disease model for the study of influenza vaccines, but a more recent use has been for the study of human monoclonal antibodies directed against influenza viruses. Published data suggest that human antibodies are cleared unusually quickly from the ferret and that immune responses may be partially responsible. This immunogenicity increases variability within groups and may present an obstacle to long-term studies. Objective Our aim was to identify an antibody design with reduced immunogenicity and longer circulating half-life in ferrets. Methods The constant region coding sequences for ferret immunoglobulin G were cloned, and chimeric human/ferret antibodies were expressed and purified. Some of the chimeric antibodies included substitutions that have been shown to extend the half-life of human IgG antibodies. These chimeric antibodies were tested for binding to recombinant ferret FcRn receptor and then evaluated in pharmacokinetic studies in ferrets. Results A one-residue substitution in the ferret Fc domain, S252Y, was identified that increased binding affinity to the ferret neonatal receptor by 24-fold and extended half-life from 65 ± 27 to 206 ± 28 hours or ?9 days. Ferrets dosed twice with this surrogate antibody showed no indications of an immune response. Conclusion Expressing the variable region of a candidate human therapeutic antibody with ferret constant regions containing the S252Y substitution can offer long half-life and limit immunogenicity. PMID:25074755

Nesspor, Thomas C; Scallon, Bernard

2014-01-01

423

Characterization and utilization of monoclonal antibodies reactive to Yersinia pseudotuberculosis.  

PubMed

The 3 murine monoclonal antibodies, Yps1, Yps2 and Yps3 reactive to Y. pseudotuberculosis can be stabilized and all were found to be of IgG type. Monoclonal antibody, Yps1, recognized a glycoprotein antigen of the organism with reactivity at the 55-75 kDa region, while Yps2 and Yps3 recognized protein antigens of Y. pseudotuberculosis 65 kDa and 26-28 kDa molecular weight regions, respectively. The specificity of monoclonal antibodies was tested using dot ELISA and Western blotting with whole cell organisms or whole cell sonicated soluble antigens of different Yersinia species, Salmonella typhi, Klebsiella pnemoniae, Streptococcus abortus-equi and Escherichia coli. Monoclonal antibody, Yps1 exhibited cross-reactivity with soluble antigens and whole cell preparations of Y. pestis. Yps2 cross-reacted to soluble antigens of all the tested bacteria. Reactivity of monoclonal antibody, Yps3 was restricted to Y. pseudotuberculosis and Y. pestis with soluble antigen preparations. No reaction was observed with Yps2 and Yps3 to whole cell organism preparations from tested bacteria including Y. pseudotuberculosis. The co-agglutination reagent prepared by sensitizing staphylococcal cells with Yps1 monoclonal antibody produced a positive agglutination with all the 4 Y. pseudotuberculosis isolates and the 3 Y. pestis strains tested. Sandwich dot ELISA using monospecific antisera as a capture antibody and a monoclonal antibody, and Yps3 as a revealing antibody had a high level of specificity in detecting Y. pseudotuberculosis antigens. PMID:15115097

Jain, Reena; Tuteja, Urmil; Batra, Harsh Vardhan

2003-12-01

424

Monoclonal antibodies in the treatment of immune thrombocytopenic purpura (ITP).  

PubMed

Immune thrombocytopenic purpura is characterized by antibody-mediated destruction of platelets and suboptimal platelet production. Initially the treatment of ITP includes corticosteroids, IgG-anti-D, and intravenous immunoglobulins. Splenectomy and monoclonal antibodies are usually considered for refractory and chronic ITP patients. There are new data suggesting that early administration of rituximab is important, and this antibody has been used as first-line therapy in adults. In this concise review the role of rituximab and other monoclonal antibodies is analyzed. These agents have the capability of sparing splenectomy and possibly curing the disease in some patients. PMID:22507772

Gómez-Almaguer, David

2012-04-01

425

Overcoming the susceptibility gap between maternal antibody disappearance and auto-antibody production.  

PubMed

In the first 10-14 days of a chick's life, protection is conferred by maternal antibodies. Further broiler protection is achieved by active vaccination. However, the high level of maternal antibodies interferes with the induction of an effective immune response by vaccination at a young age. As a result, there is a gap between the reduction in protective maternal antibodies and elevation of self-produced antibodies following active vaccination. The major aim of this study was to test an approach consisting of passive and active vaccination to overcome this gap and to provide continuous resistance to infectious viral diseases during the broiler's growth period. Newcastle disease virus (NDV), which is one of the world's most prevalent infectious diseases of poultry, was tested as a model. Following subcutaneous injection of 18 hemagglutination-inhibiting (HI) units of anti-NDV immunoglobulin Y per 1-day-old chick, protective log2 antibody titers above 4 could be detected to at least 17 days of age. The combination of passive immunization on day 1 of age with attenuated live vaccination on day 10 led to high protective titers throughout the entire growth period, up to 41 days of age. Moreover, the HI titers in the group of birds immunized with the combined vaccination were significantly more homogeneous than those in the group vaccinated only with live virus. Thus, full protection against NDV of all broilers in flock during their entire growth period was achieved by a vaccination regime that combines passive immunization and live vaccination. PMID:25444785

Yosipovich, Roni; Aizenshtein, Elina; Shadmon, Roy; Krispel, Simcha; Shuster, Efrat; Pitcovski, Jacob

2015-01-01

426

Evaluation of monoclonal antibody-based capture enzyme immunoassays for detection of specific antibodies to measles virus.  

PubMed Central

Monoclonal antibodies to the hemagglutinin protein, fusion protein, phosphoprotein, matrix protein, and nucleoprotein of measles virus were evaluated as detector antibodies in capture enzyme immunoassays (EIAs) for the detection of specific serum immunoglobulin G (IgG), IgA, and IgM antibodies to measles virus. A pool of monoclonal antibodies to hemagglutinin protein and nucleoprotein proved optimal and was further evaluated. Specific IgM was detected in 97% of adolescents with clinical measles, 97% of infants 3 weeks postvaccination, and less than 1% of normal serum specimens. Specific IgA antibodies were found in 97% of adolescents with clinical measles, 97% of infants 3 weeks postvaccination, and less than 1% of normal serum specimens. Specific IgA antibodies were found in 97% of clinical measles cases and vaccinees, in 26% of healthy persons, and in 36% of infants 8 months postvaccination; consequently, IgA antibodies were not a useful indicator of recent measles infection. A significant increase in IgG antibodies between paired specimens was detected in 92% of clinical cases and all vaccinees. Only 59% of infant specimens had persistent IgG antibodies as detected by capture EIA at 8 months postvaccination, whereas all specimens had antibodies as detected by hemagglutination inhibition and plaque neutralization. An alternative indirect EIA, in which antigen was directly absorbed to the solid phase, was more sensitive than the capture design, detecting IgG antibodies in all infants postvaccination. When standardized with a microneutralization assay for the detection of persistent antibodies, the indirect IgG EIA gave predictive values for positive and negative tests exceeding 90%. Our capture IgM and indirect IgG EIAs provide a practical combination of serologic tests for the determination of acute measles virus infection and past exposure to measles virus or vaccine, respectively. PMID:1885743

Erdman, D D; Anderson, L J; Adams, D R; Stewart, J A; Markowitz, L E; Bellini, W J

1991-01-01

427

Stable expression of a recombinant human antinucleosome antibody to investigate relationships between antibody sequence, binding properties, and pathogenicity  

Microsoft Academic Search

When purified under rigorous conditions, some murine anti-double-stranded-DNA (anti-dsDNA) antibodies actually bind chromatin rather than dsDNA. This suggests that they may actually be antinucleosome antibodies that only appear to bind dsDNA when they are incompletely dissociated from nucleosomes. Experiments in murine models suggest that antibody–nucleosome complexes may play a crucial role in the pathogenesis of glomerulonephritis in systemic lupus erythematosus.

Lesley J Mason; Anastasia Lambrianides; Joanna D Haley; Jessica J Manson; David S Latchman; David A Isenberg; Anisur Rahman

2005-01-01

428

Autoantibody potential of cancer therapeutic monoclonal antibodies.  

PubMed

We and others have reported that multiple autoantibodies are unmasked in human polyclonal antibody preparations after exposure to physiological oxidizing agents (hemin) or electromotive force. We now have asked if oxidation unmasks autoantibody reactivities in monoclonal antibodies (mAb). To do this, we have studied 9 FDA approved mAb used therapeutically, including 4 chimeric, 4 humanized and 1 chemically modified chimeric Fab that were exposed to the physiological oxidizing agent hemin at 36 degrees C for 20 hr. These mAb were studied for autoantibody activity to phospholipids and DNA before and after oxidation with hemin and found to develop autoantibody activities after oxidation, while retaining their original specificity as measured by mAb anti-glycophorin A binding of erythrocytes, CD 19 binding to B lymphocytes and anti-HLA-A29 binding to A29-positive lymphocytes. The finding that certain mAb have the potential to unmask autoantibody activities as a consequence of exposure to physiological redox reactions in vitro gives pause to our present understanding of the immunological basis of tolerance and concern for potential autoimmune side effects in patients receiving mAb for diagnosis or treatment. PMID:19904753

McIntyre, John A; Faulk, And W Page

2010-07-15

429

Immunofluorescent antibody test for diagnosis of gonorrhoea.  

PubMed Central

An indirect fluorescent antibody test was evaluated in 198 cases of a high-risk group with a culture prevalence of 37.3% and in 426 cases of a low-risk group with a culture prevalence of 1.16%. A sensitivity of 77.1% in the culture-positive patients with uncomplicated gonorrhoea, and a specificity of 88.7% in the culture- and history-negative cases, was obtained in the high-risk group. In this group, the sera from 88.8% of the patients with culture-proven gonorrhoea became positive in an indirect fluorescent antibody test within 3 weeks of last sexual contact. In the low-risk group, for which the sensitivity could not be determined due to various reasons, a specificity of 95.8% was obtained. Complement fixation test was positive in sera of only 17.6% of the culture-positive cases of the high-risk group. PMID:809468

Caloenescu, M; Clecner, B; Petrow, S; Kasatiya, S S

1975-01-01

430

Arming antibodies: prospects and challenges for immunoconjugates.  

PubMed

Immunoconjugates--monoclonal antibodies (mAbs) coupled to highly toxic agents, including radioisotopes and toxic drugs (ineffective when administered systemically alone)--are becoming a significant component of anticancer treatments. By combining the exquisite targeting specificity of mAbs with the enhanced tumor-killing power of toxic effector molecules, immunoconjugates permit sensitive discrimination between target and normal tissue, resulting in fewer toxic side effects than most conventional chemotherapeutic drugs. Two radioimmunoconjugates, ibritumomab tiuxetan (Zevalin) and tositumomab-131I (Bexxar), and one drug conjugate, gemtuzumab ozogamicin (Mylotarg), are now on the market. For the next generation of immunoconjugates, advances in protein engineering will permit greater control of mAb targeting, clearance and pharmacokinetics, resulting in significantly improved delivery to tumors of radioisotopes and potent anticancer drugs. Pre-targeting strategies, which separate the two functions of antibody-based localization and delivery or generation of the toxic agent into two steps, also promise to afford superior tumor targeting and therapeutic efficacy. Several challenges in optimizing immunoconjugates remain, however, including poor intratumoral mAb uptake, normal tissue conjugate exposure and issues surrounding drug potency and conditional release from mAb carriers. Nonetheless, highly promising results from preclinical models will continue to drive the clinical development of this therapeutic class. PMID:16151407

Wu, Anna M; Senter, Peter D

2005-09-01

431

Antibodies with thiol-S-transferase activity  

SciTech Connect

A major detoxification pathway used by aerobic organisms involves the conjugation of the tripeptide glutathione (GSH) to the electrophilic center of toxic substances. This reaction is catalyzed by a class of enzymes referred to as the glutathione S-transferases (GST) (EC 2.5.1.18). These enzymes activate the cysteine thiol group of GSH for nucleophilic addition to a variety of substrates, including aryl halides, {alpha}{beta}-unsaturated aldehydes and ketones, and epoxides. Despite the availability of X-ray crystal structures, the mechanism whereby glutathione transferases catalyze these addition reactions remains unclear. In order to gain a greater understanding of this important biological transformation, as well as to generate new detoxification catalysts, we have asked whether antibodies can be generated that catalyze similar nucleophilic addition reactions. Our initial efforts focused on the addition reaction of thiol nucleophiles to the nitro-substituted styrene derivative 1. The ratio of k{sub cat}/K{sub m} reported for the reaction of the isozyme 4-4` of rat liver GST with the good substance, 1-chloro-2,4-dinitrobenzene, is approximately 10{sup 4} M{sup -1} s{sup -1} compared to a calculated pseudo-first-order rate constant for the uncatalyzed reaction of approximately 3 x 10{sup -2} s{sup -1} (60 mM GSH, pH = 80). These comparisons suggest that with further improvements in hapten design, catalytic antibodies may prove a good source of detoxification catalysts. 19 refs., 1 fig.

Fan, E.; Oei, Yoko; Sweet, E.; Uno, Tetsuo; Schultz, P.G. [Univ. of California, Berkeley, CA (United States)] [Univ. of California, Berkeley, CA (United States)

1996-06-12

432

Mechanisms of action of CD20 antibodies  

PubMed Central

Therapeutic monoclonal antibodies (mAbs) that target the CD20 antigen on B cells are successfully used in the clinic for the depletion of B cells to treat various forms of cancer and autoimmune diseases. The first CD20 mAb, approved by the FDA in 1998, was rituximab (RTX) and since then it has been widely used to treat more than one million patients thus far. The success of RTX has led to a general interest in the mechanism of action of CD20 mAbs. CD20 mAbs can induce tumor killing via various mechanisms, such as direct induction of apoptosis, antibody-dependent cell-mediated cytotoxicity (ADCC) or complement-dependent lysis (CDC). Although we now understand these mechanisms better, it is still unclear which of these mechanisms is the most important for in vivo RTX action. Not every patient respond to RTX treatment and eventually the overwhelming majority will experience a relapse. Therefore, there is an urgent need to improve the efficacy of CD20 mAbs. This review aims to summarize our current understanding on the mechanism of action of CD20 mAbs. PMID:23226614

Boross, Peter; Leusen, Jeanette H W

2012-01-01

433

Seropositivity of Dengue Antibodies during Pregnancy  

PubMed Central

Purpose. Malaysia a dengue endemic country with dengue infections in pregnancy on the rise. The present study was aimed at determining dengue seroprevalence (IgG or IgM) during pregnancy and its neonatal transmission in dengue seropositive women. Methods. Maternal with paired cord blood samples were tested for dengue antibodies (IgG and IgM) using an enzyme-linked immunosorbent assay (ELISA). Maternal age, parity, occupation, ethnic group, and gestational age were recorded. Data on neonatal Apgar score and admissions to the Neonatal Intensive Care Unit (NICU) were analyzed. Results. Out of 358 women recruited, about 128 (35.8%) patients were seropositive. Twelve patients (3.4%) had recent infections (IgM positive) and another 116 women (32.4%) were with past infections (IgG positive). All babies born to seropositive mothers had positive IgG paired cord blood; however, no IgM seropositivity was observed. All neonates had good Apgar scores and did not require NICU admission. Conclusion. In this study, 35.8% pregnant women were found to be dengue seropositive. However, transplacental transfer of IgG antibodies had no detrimental effect on the neonatal outcomes. PMID:25587564

Mohamed Ismail, Nor Azlin; Wan Abd Rahim, Wan Elly Rushima; Salleh, Sharifah Azura; Neoh, Hui-Min; Jamal, Rahman; Jamil, Muhammad Abdul

2014-01-01

434

Ion exchange chromatography of antibody fragments.  

PubMed

Effects of pH and conductivity on the ion exchange chromatographic purification of an antigen-binding antibody fragment (Fab) of pI 8.0 were investigated. Normal sulfopropyl (SP) group modified agarose particles (SP Sepharosetrade mark Fast Flow) and dextran modified particles (SP Sepharose XL) were studied. Chromatographic measurements including adsorption isotherms and dynamic breakthrough binding capacities, were complemented with laser scanning confocal microscopy. As expected static equilibrium and dynamic binding capacities were generally reduced by increasing mobile phase conductivity (1-25 mS/cm). However at pH 4 on SP Sepharose XL, Fab dynamic binding capacity increased from 130 to 160 (mg/mL media) as mobile phase conductivity changed from 1 to 5 mS/cm. Decreasing protein net charge by increasing pH from 4 to 5 at 1.3 mS/cm caused dynamic binding capacity to increase from 130 to 180 mg/mL. Confocal scanning laser microscopy studies indicate such increases were due to faster intra-particle mass transport and hence greater utilization of the media's available binding capacity. Such results are in agreement with recent studies related to ion exchange of whole antibody molecules under similar conditions. PMID:17096387

Ljunglöf, Anders; Lacki, Karol M; Mueller, Jay; Harinarayan, Chithkala; van Reis, Robert; Fahrner, Robert; Van Alstine, James M

2007-02-15

435

Immunostimulatory antibodies: challenging the drug testing paradigm.  

PubMed

The recently failed first-in-man clinical trial of TGN1412 raises concerns about whether the existing drug testing paradigm is suited to the safety assessment of drugs based on immunostimulatory antibodies that have complex and novel mechanisms of action. In particular, there is a need to consider whether animal studies are relevant and, if so, how the resulting information can be used to best inform clinical studies. The preclinical testing of TGN1412 is considered in relation to the selection of a suitable test species, deficiencies in an understanding of the similarities and differences between human and other primate immune functioning and species extrapolation. It is concluded that more emphasis should be placed on the development and use of in vitro and computational methods to identify potentially important species differences in the activity of immunostimulatory antibodies. Such approaches are useful with regards to species extrapolation, mechanistic studies and the design of both preclinical tests in animals and clinical studies in humans. PMID:17434714

Bhogal, N; Combes, R

2007-10-01

436

Human tumor antigens identified with monoclonal antibodies  

SciTech Connect

MoAbLc1 (IgM) and MoAbLc2 (IgG/sub 2a/) were produced against human lung carcinoma cell line (ChaGo). Lc1 recognizes a approx. = 330-kd/approx. = 310-kd glycoprotein complexes, and Lc2 recognizes a approx. = 60-kd/approx. = 47-kd protein complex. With a panel of cell lines of different tissue origin, Lc1 showed a more restricted reactivity to ChaGo; it cross-reacted with another lung carcinoma cell line (SK-Lc-2) and two breast carcinoma cell lines, but failed to react with cell lines of fetal lung, of colon, esophageal, prostate, stomach, and ovarian carcinomas, of B and T lymphoblastoid cells, neuroblastomas, glioblastoma, astrocytoma, and human peripheral blood lymphocytes. New and improved methods were developed for the production of indium-111-labeled MoAbs for tumor imaging. To facilitate the application of bicyclic anhydride diethylenetriaminepentaacetic acid (BADTPA) to In-111 labeling of antibodies, we have modified the original method by using C-14-labeled BADTPA, which allows precise quantitation of DTPA molecules incorporated. A new heterobifunctional reagent, 2,6-dioxo-N-(carboxyl)morpholine (DCM) was synthesized for chelating In-111 to MoAbs, and demonstrated higher retention of immunoreactivity of the labeled antibody.

AlSedairy, S.T.

1987-01-01

437

Clinical laboratory applications of monoclonal antibodies.  

PubMed Central

Monoclonal antibody (MAb) technology is well recognized as a significant development for producing specific serologic reagents to a wide variety of antigens in unlimited amounts. These reagents have provided the means for developing a number of highly specific and reproducible immunological assays for rapid and accurate diagnosis of an extensive list of diseases, including infectious diseases. The impact that MAbs have had in characterizing infectious disease pathogens, as well as their current and future applications for use in clinical microbiology laboratories, is reviewed. In addition, the advantages (and disadvantages) of the use of MAbs in a number of immunoassays, such as particle agglutination, radioimmunoassays, enzyme-linked immunosorbent assays, immunofluorescent-antibody assays, and immunohistology, are explored, including the use of these reagents in novel test system assays. Also, nucleic acid probe technology is compared with the use of MAbs from the perspective of their respective applications in the diagnosis of infectious disease agents. There is no question that hybridoma technology has the potential to alter significantly the methods currently used in most clinical microbiology laboratories. PMID:3058298

Payne, W J; Marshall, D L; Shockley, R K; Martin, W J

1988-01-01

438

Mechanisms of Allergen-Antibody Interaction of Cockroach Allergen Bla g 2 with Monoclonal Antibodies That Inhibit IgE Antibody Binding  

PubMed Central

Background Cockroach allergy is strongly associated with asthma, and involves the production of IgE antibodies against inhaled allergens. Reports of conformational epitopes on inhaled allergens are limited. The conformational epitopes for two specific monoclonal antibodies (mAb) that interfere with IgE antibody binding were identified by X-ray crystallography on opposite sites of the quasi-symmetrical cockroach allergen Bla g 2. Methodology/Principal Findings Mutational analysis of selected residues in both epitopes was performed based on the X-ray crystal structures of the allergen with mAb Fab/Fab? fragments, to investigate the structural basis of allergen-antibody interactions. The epitopes of Bla g 2 for the mAb 7C11 or 4C3 were mutated, and the mutants were analyzed by SDS-PAGE, circular dichroism, and/or mass spectrometry. Mutants were tested for mAb and IgE antibody binding by ELISA and fluorescent multiplex array. Single or multiple mutations of five residues from both epitopes resulted in almost complete loss of mAb binding, without affecting the overall folding of the allergen. Preventing glycosylation by mutation N268Q reduced IgE binding, indicating a role of carbohydrates in the interaction. Cation-? interactions, as well as electrostatic and hydrophobic interactions, were important for mAb and IgE antibody binding. Quantitative differences in the effects of mutations on IgE antibody binding were observed, suggesting heterogeneity in epitope recognition among cockroach allergic patients. Conclusions/Significance Analysis by site-directed mutagenesis of epitopes identified by X-ray crystallography revealed an overlap between monoclonal and IgE antibody binding sites and provided insight into the B cell repertoire to Bla g 2 and the mechanisms of allergen-antibody recognition, including involvement of carbohydrates. PMID:21789239

Glesner, Jill; Wünschmann, Sabina; Li, Mi; Gustchina, Alla; Wlodawer, Alexander; Himly, Martin; Chapman, Martin D.; Pomés, Anna

2011-01-01

439

Fully human monoclonal antibodies from antibody secreting cells after vaccination with Pneumovax®23 are serotype specific and facilitate opsonophagocytosis.  

PubMed

B lymphocyte memory generates antibody-secreting cells (ASCs) that represent a source of protective antibodies that may be exploited for therapeutics. Here we vaccinated four donors with Pneumovax®23 and produced human monoclonal antibodies (hmAbs) from ASCs. We have cloned 137 hmAbs and the specificities of these antibodies encompass 19 of the 23 serotypes in the vaccine, as well as cell wall polysaccharide (CWPS). Although the majority of the antibodies are serotype specific, 12% cross-react with two serotypes. The Pneumovax®23 ASC antibody sequences are highly mutated and clonal, indicating an anamnestic response, even though this was a primary vaccination. Hmabs from 64% of the clonal families facilitate opsonophagocytosis. Although 9% of the total antibodies bind to CWPS impurity in the vaccine, none of these clonal families showed opsonophagocytic activity. Overall, these studies have allowed us to address unanswered questions in the field of human immune responses to polysaccharide vaccines, including the cross-reactivity of individual antibodies between serotypes and the percentage of antibodies that are protective after vaccination with Pneumovax®23. PMID:23084371

Smith, Kenneth; Muther, Jennifer J; Duke, Angie L; McKee, Emily; Zheng, Nai-Ying; Wilson, Patrick C; James, Judith A

2013-05-01

440

Improved ligand binding by antibody-aptamer pincers.  

PubMed

To increase the affinities of antibodies or aptamers for their targets, we designed antibody-aptamer pincers (AAPs) or heterodimers for thrombin or human epidermal growth factor 2 (HER2) as a model system. For this purpose, we first conjugated a 15-mer or 29-mer anti-thrombin aptamer, which are well-known to bind to thrombin in two specific epitopes, with an anti-thrombin antibody to enable each binding part of the AAP to simultaneously recognize a different part of the thrombin molecule. The AAP comprising a 15-mer aptamer and an anti-thrombin antibody has an apparent dissociation constant (Kd(app)) value of 567 pM, and this value is approximately 1/100 of that of the antibody alone or 1/35 of that of the aptamer monomer alone. The AAP comprising a 29-mer aptamer and an anti-thrombin antibody has a much lower Kd(app) value than that of 15-mer aptamer-conjugated antibody. Furthermore, this concept of the AAP system was employed to HER2-targeted drug delivery system (DDS) based on both antibody and drug-loaded aptamer. Anti-HER2 aptamer was conjugated with anti-HER2 antibody and loaded with doxorubicin, and the resulting AAP-HER2-Dox was found to have approximatel