Structure of Antibodies with Shared Idiotypy: The Complete Sequence of the Heavy Chain Variable Regions of Two Immunoglobulin M Anti-Gamma Globulins

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 71; no. 10; pp. 4032 - 4036
• Main Authors: Capra, J. Donald, Kehoe, J. Michael
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 01.10.1974; National Acad Sciences
• Subjects: Amino Acid Sequence; Amino acids; Antibodies; Antibodies, Anti-Idiotypic; Antibody Specificity; Binding sites; Binding Sites, Antibody; Biochemistry; Biological Sciences: Immunology; Chromatography, Gel; Cryoglobulins - analysis; Cyanogen Bromide; Epitopes; Germ cells; Globulins; Humans; Immunoglobulin Fragments; Immunoglobulin Heavy Chains; Immunoglobulin M; Immunoglobulins; Immunology; Molecules; Myeloma proteins; Myeloma Proteins - analysis; Peptide Fragments - analysis
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.71.10.4032

The complete amino acid sequence of the heavy chain variable regions of two different molecules of immunoglobulin M anti-gamma globulin has been determined. These proteins, from different human patients, had independently been shown to share idiotypic specificity. Only eight sequence differences were discernible for the entire length of their heavy chain variable regions. Five of the differences occurred outside hypervariable regions, while three were placeable within such regions. A comparison of these molecules of anti-gamma globulin with the seven human VHIII variable region sequences presently available for immunoglobulins without known antibody activity showed that the great majority of sequence differences between the two idiotypically similar antibodies and these seven proteins were confined to hypervariable regions. This study illustrates in precise terms a convergence of the distinct immunological properties of idiotypy, hypervariable region structure, and combining site specificity as they relate to the variable region of the immunoglobulin molecule. To a great degree these properties now appear to be a reflection of the same structural attributes of the variable region.