Isoelectric Focusing of an Anti-HL-A2 Antiserum Cross-Reacting with W28

Abstract

The cytotoxic activity of an anti-A2 antiserum cross-reactive with W28 appeared in 3 distinct peaks after the serum was subjected to isoelectric focusing. The pH at which the peaks formed was reproducible using pH 5-8 or pH 3.5-10 gradients. Anti-HL-A2 activity occurred in each peak, but the cross-reactive anti-W28 cytotoxicity appeared to be largely confined to the 2nd and 3rd peaks. The 1st peak was exclusively IgG [immunoglobulin G], the 2nd contained IgG and IgM, and the third contained IgG, IgA and IgM.