Rabbit anti-EL4 serum. A reagent with specificity for a population of murine suppressor cells.

Antisera against the C57B1 (H-2b) mouse lymphoma, EL4 were prepared in rabbits. After absorption with mouse liver, red cells and thymocytes the antisera appeared to be cytotoxic for a subpopulation of peripheral T cells. The absorbed antisera blocked the immunosuppressor function of Con A-stimulated splenic lymphocytes, but was unreactive against Con A-stimulated and allogeneically primed cytotoxic cells, or helper T cells. Consequently, heteroantiserum against EL4 may provide a useful reagent for the differentiation of cytotoxic from suppressor T-cell subsets.