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

Abstract

The cytotoxic activity of an anti-HL-A2 antiserum (1-oss-reactive with W28 appeared in three distinct peaks after the serum was subjected t o isoelectric focusing. The pH at which the peaks formed was reproducible using pH 5-8 or pH 3..5 10 gradients. Anti-HLA2 activity occurred in each peak, but the cross-reactive anti-W28 cytotoxicity appeared to be largely confined t o the second and third peaks. The first peak was exclusively Ig<;, the second contained Ig(; and IgM, and the third contained IgC, IgA, and IgM.Received for fiiLblzcrrtzon I Juls. riccuplrd 12 Orfobrr 197.5

Rabbit Complement in the Lymphocytotoxicity Test

“…3) Finally the immunoglobulin class of HLA antibodies should be considered as a factor causing uneven results in cytotoxicity tests involving sera from different sourcq against a given HLA specificity. HLA antibodies do not belong only to the IgG class, as initially reported by Ahrons & Glavind-Kristensen (1971) but also may be IgM and IgA (Ferrone et al 1974a, Reisner et al 1976. Immunoglobulin classes vary in their abilities to interact with complement and to activate the classical and alternative pathways of the complement system (Speigelberg & Gotze 1972.…”