DISC ELECTROPHORESIS PATTERNS OF FD FRAGMENT OF RABBIT IMMUNOGLOBULIN FRACTIONS AND OF PURIFIED ANTIBODIES

Heavy chains of rabbit immunoglobulin G, of its acidic and basic fractions obtained upon chromatography on DEAE-Sephadx, as well as of purified antibodies, were cleaved with CNBr, and the corresponding Fd fragments were isolated. The fully reduced and carboxymethylated Fd fragments wer subjected to acrylamide gel ectrophoresis. The Fd fragments of immunoglobulin G resolved into 10-12 bands. No significant differences were found in the electrophoretic mobility of bands from Fd fragments derived from acidic and basic immunoglobulin fractions, so it seems that the charge difference between the two immunoglobulin fractions separable on DEAE-Sephadex is due mostly to the light chains. The band patterns of Fd fragments derived from purified antibodies are significantly different from one antibody to another, and it si possible that this might correlate with antibody specificity. © 1969.