Abstract: | Living spleen cells and a subcellular product of spleen cells have been compared, in mice, for their ability to elicit, for a long term culture (4-5 days), a cellular cytotoxic response against alloantigens. Contrary to living spleen cells which could induce the same high level of cytotoxic activity in a primary or in a secondary response, the antigenic preparation was only able to mount a very low primary response while it could render highly cytotoxic a lymphoid population proved to be able to mount in vitro an anamnestic response. |