Enhancement of tumor growth in allogeneic mice following impairment of macrophage function.

Teratoma 402 AX is an embryo-like tumor cell line originally derived from the testicles of strain 129/J mice. This teratocarcinoma grows well in males and pregnant females but poorly in virgin females when given in small doses. Induction of growth of this tumor is syngeneic and allogeneic virgin females was achieved by modification of macrophage function by antimacrophage serum. Tumor-bearing animals of both sexes, whether treated with antimacrophage serum or normal rabbit serum, produce antitumor antibodies of the IgM, IgA, IgG, IgG, and IgG classes. These antibodies are bound to the tumor cell surface and are not cytotoxic to the target cell in the presence of rabbit or guinea pig complement.