Homogeneous antibodies sequences

Sequence determinations showed that in some regions of immunoglobulin molecules there is extreme variation in the amino acid sequence between one homogeneous antibody and the next other regions have a constant sequence. The molecule can also be divided into domains. The variable regions, which occupy the N-terminal ends of the chains, are designated... 

Schilling, J., Clevinger, B., Davie, J.M., Hood, L. (1980). Amino acid sequence of homogeneous antibodies to dextran and DNA rearrangements in heavy chain V-region gene segments. Nature 283, 35-40. 

Further sequence analysis by Mole et al. (1971) of pooled IgG heavy chains of either allotype al or a3 delineated additional areas for potential allotypic correlations (Todd, 1972). These were compared with the sequence of a homogeneous antibody of allotype a2 (Fleischman, 1971). These studies showed, when corrected for hypervariable sequences and group a negative molecules, that amino acid interchanges occurring at positions 4, 7, 9, 11, 12, 15, and 16 could be correlated with group a allotypes. In addition substitutions at positions 80-85 from the amino-terminal end of the heavy chain could also be associated with allotypic differences. 

Capra et al. (1971) examined the light chains from some homogeneous antibodies derived from patients with hypergammaglobulinemic purpura. All these antibodies had IgG-ligating activity. The amino acid residue sequence was identical in some up to residue 40 between others... 

The very high concentrations of antibody resulting from immunization with bacterial vaccines have been of particular importance for the isolation of homogeneous antibody in amounts sufficient for physicochemical studies and determinations of amino acid sequence. In addition, the high titers facilitate the detection of homogeneous subpopulations. 

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