Antibody

About: Antibody is a research topic. Over the lifetime, 113941 publications have been published within this topic receiving 4130181 citations. The topic is also known as: Ab & antibodies.

Multiple Distinct Sets of Stereotyped Antigen Receptors Indicate a Role for Antigen in Promoting Chronic Lymphocytic Leukemia

Abstract: Previous studies suggest that the diversity of the expressed variable (V) region repertoire of the immunoglobulin (Ig)H chain of B-CLL cells is restricted. Although limited examples of marked constraint in the primary structure of the H and L chain V regions exist, the possibility that this level of restriction is a general principle in this disease has not been accepted. This report describes five sets of patients, mostly with unmutated or minimally mutated IgV genes, with strikingly similar B cell antigen receptors (BCRs) arising from the use of common H and L chain V region gene segments that share CDR3 structural features such as length, amino acid composition, and unique amino acid residues at recombination junctions. Thus, a much more striking degree of structural restriction of the entire BCR and a much higher frequency of receptor sharing exists among patients than appreciated previously. The data imply that either a significant fraction of B-CLL cells was selected by a limited set of antigenic epitopes at some point in their development and/or that they derive from a distinct B cell subpopulation with limited Ig V region diversity. These shared, stereotyped Ig molecules may be valuable probes for antigen identification and important targets for cross-reactive idiotypic therapy.

Autoimmunity in a Phase I Trial of a Fully Human Anti-Cytotoxic T-Lymphocyte Antigen-4 Monoclonal Antibody With Multiple Melanoma Peptides and Montanide ISA 51 for Patients With Resected Stages III and IV Melanoma

Abstract: Purpose Nineteen patients with high-risk resected stage III and IV melanoma were immunized with three tumor antigen epitope peptides from gp100, MART-1, and tyrosinase emulsified with adjuvant Montanide ISA 51 and received a fully human anti-cytotoxic T-lymphocyte antigen-4 (anti–CTLA-4) monoclonal antibody MDX-010. Each of three cohorts received escalating doses of antibody with vaccine primarily to evaluate the toxicities and maximum-tolerated dose (MTD) of MDX-010 with vaccine. MDX-010 pharmacokinetics and immune responses were secondary end points. Patients and Methods Peptide immunizations with MDX-010 were administered every 4 weeks for 6 months and then every 12 weeks for 6 months. A leukapheresis to obtain peripheral-blood mononuclear cells for immune analyses was performed before treatment and after the sixth vaccination. Patients were observed until relapse. Results Grade 3 gastrointestinal (GI) toxicity (diarrhea or abdominal pain) was observed in three patients in the highest dose cohort and o...

Monoclonal antibodies to mouse major histocompatibility complex antigens.

Abstract: As part of our continuing effort to produce a library of hybridoma antibodies specific for the products of the mouse major histocompatibility complex (MHC), nine antibodies reacting with antigens of the H-2d haplotype have been produced by cell fusion between immune spleen cells and the SP2/0.Ag.14 cell, of H-2d origin. Serological characterization revealed that seven antibodies reacted with H-2 antigens and two with Ia antigens. Of the anti-H-2 antibodies, four detected private specificities of H-2Kd or H-2Dd antigens and three detected public specificities of H-2d and other haplotypes. One of the anti-Ia antibodies detected a private Ia specificity corresponding to Ia.23 and the other detected a previously undescribed public specificity. Anti-H-2d hybridoma cells represent a potential "autoreactive" situation in that the antibodies produced by the cells should react with their own H-2 antigens unless expression of the corresponding H-2d antigens in these cells was altered. In order to examine whether H-2d antigens continued to be expressed on these anti-H-2d hybridoma cells, binding of 125I-labeled monoclonal anti-H-2Kd and/or H-2Dd antibodies was studied. Among the four hybridoma clones tested, three bound specifically three independent 125I-labeled anti-H-2d antibodies, including two cases in which binding of autologous antibodies was detected. The last clone did not bind any of the anti-H-2d antibodies, although it bound an anti-H-2k antibody, indicating selective loss of H-2d antigens. These observations demonstrate that neither loss nor retention of H-2d antigen expression on the cell surface is obligatory in hybridoma cells producing anti-H-2d antibodies.