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B L Clevinger

Publications and source records attributed to B L Clevinger.

10 recordsLinked to original sources

Autoimmune mice and stimulated normal mice make lambda 1 with increased V region diversity.

Previous studies of the genetic bases of murine SLE have defined gene segments that encode the H chain and the kappa L chain of anti-DNA, anti-Sm, and anti-IgG autoantibodies. As a result of these studies, the genetic origins of autoantibody H chains and kappa L chains are better understood, but little remains known about the genetic bases of autoantibody lambda-chains. Thus, we have analyzed serologically the germ-line and somatic origins of lambda 1 L chains in antibodies of normal mice and in both antibodies and autoantibodies of autoimmune mice. This study finds an increased lambda 1 diversity in both Ag-stimulated mice and autoimmune mice. This study also finds that the lambda 1 L chains in antibodies of unstimulated normal mice have the gene segment-encoded variable region, V lambda 1. In contrast, additional genetic processes appear to make the lambda 1 V regions of antibodies in Ag-stimulated normal mice and the lambda 1 V regions of both antibodies and autoantibodies in autoimmune mice. The increased lambda 1 diversity that we found in both Ag-stimulated mice and autoimmune mice might be caused by mutational processes creating antibody diversities. Therefore, the same somatic processes might be able to make both antibody and autoantibody lambda 1 diversities.

Animals↗

Immunochemical studies of mouse monoclonal antibodies to dextran B1355S--II. Combining site specificity, sequence, idiotype and affinity.

The specificities of the combining sites of 19 mouse monoclonal antibodies to dextran B1355S have been characterized immunochemically by quantitative precipitin and precipitin inhibition assays; association constants for B1355S were determined by affinity gel electrophoresis. Cross-reactive and individual idiotypes related to the BALB/c B1355S-binding myeloma proteins MOPC104E [IdI(MOPC104E)] and J558 [IdI(J558)], determined by a radioimmunoassay, and heavy-chain variable-region sequences, are presented. Antibodies to B1355S are "alpha (1----3) alpha (1----6)-specific" as determined by precipitin and precipitin inhibition assays with dextrans and oligosaccharides, respectively, containing alternating alpha (1----3) alpha (1----6) linkages compared with oligosaccharides composed solely of alpha (1----3) or alpha (1----6) linkages; all antibodies have low association constants (less than or equal to 10(5) ml/g). However, there is also considerable diversity among the proteins as seen in the five groups of different patterns of reactivity with numerous dextrans having different structures, and the variability in affinity even among antibodies showing the same fine specificity by precipitin assay. There is little observable correlation of heavy-chain variable-region amino-acid sequence with specificity or affinity; however, all proteins having D-region amino acids Tyr,Asp at positions 96,97 express the MOPC104E individual idiotype and belong to precipitin specificity group 5, the group most cross-reactive with numerous dextrans, whereas those proteins having the J558 individual idiotype, Arg,Tyr or Asn,Tyr at 96,97 are found in all five precipitin groups.

Amino Acid Sequence↗

Monoclonal antibody with high affinity for 1,25-dihydroxycholecalciferol.

We have developed a monoclonal antibody capable of detecting 1 pg/ml of 1,25-dihydroxycholecalciferol. At a dilution of 1:80,000 of ascitic fluid this antibody has an apparent KD of 3.3 X 10(-11) ML-1. The immunogen used was a vitamin D analogue, calcitroic acid [1 alpha, 3 beta-dihydroxy-9, 10 seco-24-nor 5, 7, 10 (19) cholatriene-23-oic acid], conjugated to bovine serum albumin. Although this antibody is extremely sensitive, it also recognizes other important vitamin D3 metabolites.

Animals↗

Combining site specificities of mouse hybridoma antibodies to dextran B1355S.

The combining sites of 12 mouse hybridoma antibodies to dextran B1355S have been characterized by quantitative precipitin assay. All antibodies preferentially bind the immunizing antigen B1355S and two other class I dextrans, B1498S and B1501S, but show substantial differences in the extents to which they cross react with class I dextrans, suggesting their clustering into five groups. Three myeloma proteins, CAL20 TEPC1035, J558, and MOPC104E, which bind dextran B1355S, each fall into a different group. There appears to be a substantial, but imperfect, correlation of DH region structure and individual idiotypic determinants with dextran binding patterns. Proteins with RY DH segments and IdI (J558) idiotypes are in groups 1 or 3, and proteins with YD DH segments and IdI (MOPC104E) idiotypes are exclusively in group 5. However, identical patterns of precipitin curves accompany very different sequences in CDR3. Antibodies of group 1, which react only with class II dextrans, differ the most in primary sequence, a finding suggesting that subsites responsible for cross reactivity with class I dextrans may be blocked and that this may be effected by side chains of different amino acids. This finding delineates a new aspect of the relationship of variability in amino acid sequence to antibody complementarity.

Amino Acid Sequence↗

Monoclonal antibodies to streptococcal group A carbohydrate. I. A dominant idiotypic determinant is located on Vk.

In an effort to better define the antibody repertoire to streptococcal group A carbohydrate (GAC), somatic cell hybrids were prepared from A/J mice immunized with streptococcal vaccine. Most antibodies were IgG3K and IgMK, while 2 of 26 antibodies were lambda type. Each of the IgG3 antibodies had a distinct isoelectric point consistent with previous estimates of clonal repertoires of approximately 200. IEF analysis of the L chains, however, showed that about half of the antibodies produce a common L chain, called VK1GAC, previously identified in A/J anti-GAC serum antibodies. Additional support for the structural similarity of these L chains was gained by developing an idiotype antiserum to VK1GAC. All proteins with the common L chain spectrotype react strongly with anti-VK1GAC. Thus, it appears that anti-GAC antibodies are composed of H chains bearing a few VH regions pairing with a few L chains.

Animals↗

Regulation of murine B cells through surface immunoglobulin. I. Monoclonal anti-delta antibody that induces allotype-specific proliferation.

We describe the identification of a monoclonal antibody that recognizes a determinant on the delta chain of mice of the Iga, allotype groups. The monoclonal Ig in soluble form induces allotype-specific proliferation by splenic B lymphocytes from normal animals of these haplotypes. Spleen cells from mice bearing the X-linked defect of CBA/N mice fail to respond, although they bear the determinant. Proliferation is independent of T lymphocytes. The data indicate a direct triggering function for sIgD.

Animals↗

Subclass restriction of murine antibodies. III. Antigens that stimulate IgG3 in mice stimulate IgG2c in rats.

The IgG subclass distribution of rat antibodies to 13 different antigens was measured. Antibodies to protein and hapten-protein conjugates were predominantly IgG2a. Antigens labeled thymus-independent type 1, based upon responses in mice, stimulated both IgG2b and IgG2c antibodies, but little IgG2a. Polysaccharide and hapten-polysaccharide antigens (thymus-independent type 2) as well as phosphocholine-keyhole limpet hemocyanin, stimulated predominantly IgG2c antibodies. A division of antigens into essentially the same categories has been made on the basis of subclass restriction in mice. Antigens that stimulate IgG2c in rats stimulate IgG3 in mice. Thus, by comparing subclass preference with a variety of antigens, functional analogues among subclasses in different species can be identified.

Animals↗

Suppression of antibody and T cell proliferative responses to L-glutamic acid60-L-alanine30-L-tyrosine10 by a specific monoclonal T cell factor.

The synthetic terpolymer L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) stimulates GAT-specific suppressor T cells in nonresponder mice. Extracts from these T cells contain a GAT-specific soluble T cell suppressor factor (GAT-TsF) that inhibits development of GAT-specific plaque-forming cell (PFC) responses by spleen cells from nonresponder mice stimulated with GAT complexed to methylated bovine serum albumin (GAT-MBSA). These extracts also contain a factor that inhibits development of GAT-specific proliferative responses by GAT-MBSA-primed, nonresponder lymph node T cells. Experiments reported in this manuscript show that a hybrid T cell line, produced by fusion of the AKR thymoma, BW5147, with spleen cells that contain GAT-specific suppressor T cells, produces a constitutive GAT-specific suppresor factor that functionally and serologically resembles GAT-TsF extracted from T cells. More importantly, both GAT-specific PFC and T cell proliferative responses are inhibited by this factor.

Animals↗

Improved diagnostic accuracy using monoclonal antibody group A streptococcal carbohydrate.

Monoclonal mouse antibody to streptococcal group A carbohydrate was evaluated in diagnostic microbiology laboratory. A total of 262 isolates of beta-hemolytic streptococci were classified with commercial reagents and the monoclonal antibody to group A carbohydrate by using immunofluorescence and Lancefield precipitin tests. Both nonoclonal and commercial antibodies were identifically reactive by the precipitin test but significantly different by immunofluroescence. Monoclonal antibody gave the same reactivity as seen in the precipitin test, but commercial antibodies gave both false-positive and false-negative results. These results suggest that monoclonal reagents may be superior to conventional antisera.

Animals↗