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J L Claflin

Publications and source records attributed to J L Claflin.

13 recordsLinked to original sources
PubMed1992

Antigen binding and idiotype analysis of antibodies obtained after electroporation of heavy and light chain genes encoding phosphocholine-specific antibodies: a model for T15-idiotype dominance.

Antibodies bearing the T15 idiotype dominate the murine primary immune response to phosphocholine (PC). Analysis of antigen binding of antibodies derived from V1:DFL16.1:JH1 (VH1) germline and N region-derived variant heavy (H) chains and kappa 22, kappa 24, and kappa 8 light (L) chains demonstrates that the T15H:kappa 22L (T15) antibody binds PC at least 20-40 times better than other antibodies derived from alternate germline forms of the VH1 H chain and kappa 22, kappa 24, or kappa 8 L chains. To achieve affinities in the same range as the T15 antibody, kappa 24 and kappa 8 L chain-containing antibodies must have H chains derived from variant N region or somatically mutated VH1 genes. Single amino acid differences at the VD junction of the various germline and N region variant VH1 H chains dictate the L chain that can associate with the H chain to produce a PC-specific antibody. Several H:L combinations give rise to T15 or M167 idiotype-positive antibodies that lack specificity for PC, and single amino acid substitutions or insertions at the VH1:D junction result in the loss of T15 or M167 idiotopes. Based on these observations, our data support a molecular model involving both preferential gene rearrangement and antigen-driven B cell selection to explain T15 idiotype dominance in the immune response to PC. In the absence of N region diversification, large numbers of neonatal B cells bearing the T15H:kappa 22L surface immunoglobulin M (sIgM) receptors would be selected and expanded by autologous or environmental PC antigen into the long-lived peripheral B cell pool.

Amino Acid Sequence↗
PubMed1979

Structural evidence for a polymorphic or allelic form of the heavy chain variable region.

The heavy (H) chains of anti-phosphocholine (PC) antibodies from C57BL/6J and CBA/J were sequenced through the N-terminal 36 residues and compared with previously published sequences of A/J anti-PC antibody and BALB/c PC-binding myeloma proteins T15, M603, and M511. Each of these antibody preparations contained molecules having light (L) chains and idiotypic determinants of T15, M511, and M603 indicating the presence of at least three different anti-PC antibodies in each pool. The structures of the C57BL/6J and CBA/J H chains each revealed a single sequence from positions 1 to 36 (which includes the first complementarity determining region (CDR), and they were identical. The first CDR was identical to that previously found for BALB/c and A/J indicating that this portion of these antibody molecules is highly conserved throughout inbred mice and is probably critical to PC-binding. A surprising finding was that both C57NL/6 and CBA sequence differed from the BALB/c and A/J sequences at two positions, residue 14 and 16. Since each of these strains differs at the allotype locus, the data indicates that the evolution of allotypy in mice occurred after variable region diversity for the particular genes.

Alleles↗
PubMed1978

Clonal nature of the immune response to phosphocholine. VI. Molecular uniformity of a single idiotype among BALB/c mice.

The molecular heterogeneity of IgG antibodies to phosphocholine (PC) having a defined idiotype was examined in BALB/c mice immunized with PC-keyhole limpet hemocyanin (KLH). Specific antibodies were separated by isoelectric focusing in polyacrylamide gels and characterized for PC-binding, idiotype, and isotype by direct in situ labeling with 125I-labeled reagents followed by autoradiography. After immunization with PC-KLH, BALB/c produce 20 to 100 microgram/ml of IgM and 80 to 300 microgram/ml of IgG anti-PC antibody. The dominant fraction of anti-PC antibodies in BALB/c (and a lesser fraction in other strains) possesses idiotypic determinants found on a PC-binding myeloma, TEPC-15. Among 65 BALB/c examined, all produced an identical spectrotypic pattern of antibodies possessing T15 idiotypic determinants. Three major sets of T15-idiotype bearing bands were observed, but they belonged to three different IgG subclasses: IgG1, IgG2, and IgG3. These data support the germ line origin for this dominant set of antibodies in the anti-PC repertoire of BALB/c and indicate that they arise from a single rather than multiple VH-VL pairs.

Animals↗
PubMed1976

Expression of equivalent clonotypes in BALB/c and A/J mice after immunization with phosphorylcholine.

Analysis of A/J antibody to phosphorylcholine (PC) revealed a striking degree of similarity to PC-binding myeloma proteins of BALB/c origin. By quantitative idiotypic analysis A/J anti-PC antibody was composed to antibodies bearing binding site idiotypic determinants indistinguishable from two different BALB/c myeloma proteins, T15 and M511. Idiotypic determinants of three other PC-binding proteins, W3207, M167, and M603 were not detected. Isoelectric focusing of the light chains verified the presence of antibodies similar to T15 and M511 and indicated the presence of a third antibody whose light chains had a pI identical to that of M603. When the sequence of A/J heavy chains were compared to the heavy chains of T15, M511, and M603, both the framework and first complementarity regions were identical in all cases. Sequences analysis of the light chains through part of the first complementarity region revealed three chains, one similar to each of the myeloma proteins T15, M603, and M167-M511. The latter two sequences differ by only a single amino acid (a single base substitution) in the first 23 residues, suggesting that the two light chains may be very similar if not identical. Thus, BALB/c and A/J mice which differ genetically at multiple loci including the heavy chain allotype complex locus show a remarkable preservation of their anti-PC antibodies. These results indicate that the genes encoding these antibodies are contained in the germ line.

Amino Acid Sequence↗
PubMed1976

Genetic marker in the variable region of kappa chains of mouse anti-phosphorylcholine antibodies.

A newly discovered genetic marker in the kappa light chains of mouse immunoglobulins is described. This marker, designated kappa-PC8, is located in the L chains of those anti-phosphorylcholine (PC) antibodies which show the same functional and idiotypic characteristics as a PC-binding myeloma protein, HOPC 8 (H8). Analytical isoelectric focusing of these L chains revealed two phenotypes whose strain distribution pattern suggested a genetic association with genes that determine the T lymphocyte surface antigen(s) Ly-2/Ly-3. In four strains , AKR/J, C58/J, RF/J and PL/J (AKR-type, A) the H8-like L chains have a slightly lower isoelectric point than those of C57L/J and 12 other strains (C57L-type, B). Breeding experiments showed that the kappa-PC8-A phenotype is preferentially expressed. The most probable location of the marker is the variable region since other idiotypically related kappa-chains in C57L/J and AKR/J do not show differences in their electrophoretic mobility.

Animals↗
PubMed1976

Uniformity in the clonal repertoire for the immune response to phosphorylcholine in mice.

A comparison of the clonal nature of the immune response to phosphorylcholine (PC) was made in nine different inbred mouse strains. Quantitative idiotypic analysis showed that anti-PC antibodies from each strain were composed of antibodies bearing binding-site idiotypic determinants indistinguishable from two different BALB/c myeloma proteins, T15 and M511. Idiotypic determinants of two other PC-binding proteins, M167 and M603, were not detected. Isoelectric focusing of the light (L) chains verified the presence of antibodies similar to T15 and M511 in each strain and indicated the presence of two additional antibodies, one of which has an L chain which cofocuses with M603. Fractionation of anti-PC antibody with anti-idiotypic antibody showed that immunoglobulins bearing T15 and M511 idiotypic determinants are separate and contain L chains that are unifore and resemble those of T15 and M511, respectively. Thus, these mice which differ genetically at multiple loci including the heavy chain allotype complex locus each possess, at least in part, an equivalent set of clonotypes specific for PC. This indicates that the genes encoding these antibodies must be contained in the germ line.

Animals↗
PubMed1975

Clonal nature of the immune response to phosphorylcholine (PC). V. Cross-idiotypic specificity among heavy chains of murine anti-PC antibodies and PC-binding myeloma proteins.

Seven mouse myeloma proteins with specificity for phosphorylcholine (PC) were found to share a common antigenic determinant. This group of proteins contained members which differed in genetic origin, heavy chain class, kappa-chain subgroup, individual antigenic determinants and specificity for choline analogues. The cross-idiotypic determinant, VH-PC, was antigenically similar in each of the proteins and was associated with the variable portion of the heavy chain in the region of the antibody combining site. Further studies showed that an indistinguishable determinant was present on IgM anti-PC antibodies isolated from all strains of mice tested regardless of histocompatibility or heavy chain allotype. In view of the finding that this cross-idiotypic determinant was not found on antibodies or myeloma proteins which lacked specificity for PC, the data strongly suggest that a particular heavy chain variable region has been preserved in all mouse antibodies with specificity for PC.

Animals↗
PubMed1975

Structural, functional, and idiotypic characteristics of a phosphorylcholine-binding IgA myeloma protein of C57BL/ka allotype.

An IgA phosphorylcholine (PC)-binding myeloma protein with IgCH allotypic determinants different from those of BALB/c mice is characterized. The myeloma, CBPC 2, was induced in the CB-20 strain of mice which is congenic to BALB/c but differs from it by carrying the A15 allotypic determinant of C57BL/ka mice. Sequence analysis of the CBPC 2 light chain through the first hypervariable region, as well as isoelectric point analysis, show that this chain is indistinguishable from that of T15, a PC-binding myeloma protein of BALB/c origin. The heavy chains of CBPC 2 and T15 differ by only two amino acids (positions 14 and 16) through the first hypervariable region. As measured by inhibition of precipitation, both CBPC 2 and T15 have the same specificity for PC, glycerophosphorylcholine, acetylcholine, and choline. In addition, CBPC 2 possesses the binding site-associated idiotypic determinant which is present on T15. However, like normal or induced C57BL/6 anti-PC antibody, it does not possess the nonbinding site idiotypic determinant.

Amino Acid Sequence↗
PubMed1975

Immune response to liposomal model membranes: restricted IgM and IgG anti-dinitrophenyl antibodies produced in guinea pigs.

Guinea pigs were immunized with liposomal model membranes actively sensitized with 2,4-dinitrophenyl-aminocaproylphosphatidyl-ethanolamine. The immune response was characterized by the formation of both IgM and IgG anti-DNP plaque-forming cells (PFC) which paralleled the appearance of anti-DNP antibodies in the serum. Plaque inhibition by DNP-lysine indicated that the PFC produced after liposomal immunization fell in a much narrower range of avidity groups than the PFC obtained after immunization with DNP-albumin and, in this regard, resembled MOPC 315. The restricted nature of the serum IgG anti-DNP antibodies was confirmed by isoelectric focusing and revealed the expression of a limited number of clones in all cases.

Animals↗
PubMed1975

Specific isolation and characterization of antibody directed to binding site antigenic determinants.

The preparation and specificity of antibodies specific for the ligand-binding site of HOPC 8, a phosphorylcholine (PC)-binding mouse myeloma protein, are described. Antiserum to HOPC 8, prepared in rabbits, was adsorbed with an HOPC 8-Sepharose immunoadsorbent and anti-binding site antibodies were eluted with PC. These antibodies reacted with HOPC 8 but not other myeloma proteins, including those with PC-binding specificity different from HOPC 8; the specificity of this anti-HOPC 8 antibody for the combining site region of HOPC 8 was shown by the fact that 1) the interaction of the anti-HOPC 8 antibody preparation with HOPC 8 was completely blocked by PC and 2) the antibody preparation failed to bind TEPC 15 in which the combining sites had been blocked by covalently bound PC groups. Moreover, these anti-binding site antibodies did not react with isolated heavy or light chains, indicating the requirement for a heavy-light chain interaction. By contrast an idiotypic antiserum to HOPC 8 prepared in A/J mice did bind affinity-labeled TEPC 15 and the reaction with HOPC 8 was only marginally hapten inhibitable. Both of the idiotypic determinants detected by these two antisera were present on anti-PC antibody raised in BALB/c mice;

Adsorption↗