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.
Kenny
J J
JJ
Program Resources, Inc/DynCorp, National Cancer Institute-Frederick Cancer Research and Development Center, Maryland 21702-1201.
Moratz
C M
CM
Guelde
G
G
O'Connell
C D
CD
George
J
J
Dell
C
C
Penner
S J
SJ
Weber
J S
JS
Berry
J
J
Claflin
J L
JL
D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D000918:Antibody Specificity; D000936:Antigen-Antibody Complex; D001483:Base Sequence; D002460:Cell Line; D004558:Electric Stimulation; D004797:Enzyme-Linked Immunosorbent Assay; D005799:Genes, Dominant; D005803:Genes, Immunoglobulin; D007143:Immunoglobulin Heavy Chains / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D007130:Immunoglobulin Idiotypes / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D007147:Immunoglobulin Light Chains / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D007135:Immunoglobulin Variable Region / Q000235:genetics; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D010767:Phosphorylcholine / Q000276:immunology*; D051381:Rats
D000936:Antigen-Antibody Complex; D007143:Immunoglobulin Heavy Chains; D007130:Immunoglobulin Idiotypes; D007147:Immunoglobulin Light Chains; D007135:Immunoglobulin Variable Region; D010767:Phosphorylcholine