Comparison of Variable Region Primary Structures within an Anti-fluorescein Idiotype Family

• Published in: The Journal of biological chemistry 1989-01, Vol.264 (3), p.1565-1569
• Main Authors: Bedzyk, W D, Johnson, L S, Riordan, G S, Voss, E W
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Antibodies, immunoglobulins; Antibodies, Monoclonal; Antibody Formation; Base Sequence; Biological and medical sciences; Fluorescein; Fluoresceins - metabolism; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Immunoglobulin Heavy Chains - analysis; Immunoglobulin Idiotypes - analysis; Immunoglobulin Light Chains - analysis; Immunoglobulin Variable Region - analysis; Molecular immunology; Molecular Sequence Data; Monoclonal antibodies
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)94224-9

Previous reports described the properties of a high affinity (Ka = 1.7×1010M−1) prototype anti-fluorescein monoclonal antibody 4-4–20, an intermediate affinity (Ka = 3.7×107M−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 Vκ II subgroup genes, respectively. Antibody 5–27 utilized a VHIII(B) and a Vκ 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 Vκ II subgroup VL-gene, and Jκ 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.