Comparison of variable region primary structures within an anti-fluorescein idiotype family.
Previous reports described the properties of a high affinity (Ka = 1.7 X 10(10) M-1) prototype anti-fluorescein monoclonal antibody 4-4-20, an intermediate affinity (Ka = 3.7 X 10(7) M-1) prototype 9-40, and Ig members of the 9-40 idiotype family (comprised of 3-24, 5-14, 5-27, 10-25 and 12-40). Although the seven monoclonal anti-fluorescein antibodies expressed similar active site structural determinants (idiotypes) as determined serologically, each was characterized by different affinities for fluorescein and fine specificity binding patterns. Partial heavy (H)- and light (L)-chain N-terminal amino acid sequence analyses revealed all antibodies (except 5-27) were composed of highly homologous VHIII(C) and V kappa II subgroup genes, respectively. Antibody 5-27 utilized a VHIII(B) and a V kappa V subgroup genes and shared low V-region sequence homology with 4-4-20, 9-40 and the remaining 9-40 idiotype family. In addition, complete 4-4-20, VH- and VL-region primary structures were determined to better understand antibody-antigen interactions. Antibody 4-4-20 utilized a VHIII(C) subgroup VH-gene, a truncated Sp2 D gene segment, JH4, a V kappa II subgroup VL-gene, and J kappa 1. Antibody 4-4-20 VH and VL complementarity-determining regions contained many basic and aromatic amino acid residues capable of interaction with fluorescein. Results are discussed in terms of idiotypic and fluorescein-binding characteristics as well as antibody structural and functional diversity in the immune response.
Bedzyk
W D
WD
Department of Microbiology, University of Illinois, Urbana 61801.
Johnson
L S
LS
Riordan
G S
GS
Voss
E W
EW
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D000917:Antibody Formation; D001483:Base Sequence; D019793:Fluorescein; D005452:Fluoresceins / Q000378:metabolism; D007143:Immunoglobulin Heavy Chains / Q000032:analysis; D007130:Immunoglobulin Idiotypes / Q000032:analysis*; D007147:Immunoglobulin Light Chains / Q000032:analysis; D007135:Immunoglobulin Variable Region / Q000032:analysis*; D008969:Molecular Sequence Data
D000911:Antibodies, Monoclonal; D005452:Fluoresceins; D007143:Immunoglobulin Heavy Chains; D007130:Immunoglobulin Idiotypes; D007147:Immunoglobulin Light Chains; D007135:Immunoglobulin Variable Region; D019793:Fluorescein