Quantitative analysis of an idiotypic determinant of light chains of normal human IgG and IgM.

Normal light chains of human IgG and IgM were analyzed for the presence of the idiotypic determinant of light chains identified by anti-"a". A quantitative evaluation indicated that this marker of the variable region was present in light chains obtained from IgG and IgM; however, light chains reacting with anti-"a" were preferentially associated with IgG molecules.