Immunity to a syngeneic methylcholanthrene-induced tumor was studied in (C57BL/6 × C3H)F1 males, treated continuously from birth with a rabbit anti-mouse IgM serum. Such mice have been shown to be selectively depleted of Ig-bearing lymphocytes and incapable of synthesizing antibodies. In the experiments reported, a heightened resistance of these mice to the syngeneic fibrosarcoma was demonstrated. This resistance was manifest in significantly slower tumor growth at the site of injection, as well as a lower incidence of spontaneous pulmonary metastasis.
This work was supported by a grant from the National Cancer Institute of Canada.