Inhibition of murine lymphoma growth by adoptive transfer of lymphocytes sensitized to a xenogenized tumor variant.

Lymphocytes immune to a highly immunogenic ("xenogenized") variant of a murine lymphoma--which were shown to exert anti-xenogenized tumor activity in a previously described model of tumor immunotherapy--were tested in the present study for possible suppressive effects on the growth of an i.c. graft of the original lymphoma. Remarkable tumor-inhibitory effects followed the i.v. infusion of splenic lymphocytes sensitized or restimulated in vitro, or derived from animals immunized in vivo with the xenogenized tumor cells. The pattern of inhibition of the parental cells was apparently similar to that previously described for the xenogenized variant, but preliminary evidence suggests that the underlying mechanisms may be different.