Induction of nonspecific cell-mediated cytotoxic reactivity from non-immune spleen cells treated with aloctin A.

Culturing of mouse spleen cells with aloctin A (Alo A), a lectin having anti-tumor activity, resulted in the induction of cells cytotoxic to syngeneic and allogenic tumor cells in vitro. Alo A-induced killer cells could be generated from spleen cells of natural killer cell-deficient beige mice but not from those of T cell-deficient nude mice. The results of cytotoxicity assay after treatment with antisera plus complement indicated that the killer cells mainly consisted of Thy 1+, Lyt 1-2+, asialo GM1(1)-T cells. Their cytotoxic activity was markedly augmented by the presence of Alo A during the assay for cytotoxicity. The assay of IL2 in the culture fluid from Alo A-treated spleen cells and the effect of dexamethasone (DEX) on IL2 production from Alo A-stimulated spleen cells and on generation of killer cells suggested that generation of Alo A-induced killer cells was closely associated with the amount of IL2 released from the spleen cells in culture.