ANTI-TUMOR EFFECT OF SYNGENEIC SPLEEN-CELLS TREATED WITH IMMUNE RNA AND TUMOR-ANTIGEN

  • 1 January 1982
    • journal article
    • research article
    • Vol. 29  (1) , 113-117
Abstract
The antitumor effect of syngeneic spleen cells, xenogeneic immune RNA (I-RNA) and tumor antigen (TA) was studied in a chemically induced (N-methyl-N-nitrosourethane) colon carcinoma model in BALB/c mice. When the mice were treated, sequentially, with these 3 elements by local injection under the tumor, complete tumor regression was observed in 25% of the animals. Complete tumor regression was observed in 17% of animals treated by injection of spleen cells preincubated with I-RNA in vitro followed by an injection of TA. When spleen cells were treated first with I-RNA and then with mitomycin-C, therapeutic benefit was obtained and the survival rate of mice treated with these spleen cells and TA was significantly higher than that of the control group (no treatment). The antitumor effect of this treatment was abrogated completely when spleen cells were treated with mitomycin-C prior to I-RNA incubation. When spleen cells were incubated with TA in vitro or after incubation with I-RNA and then injected into tumor-bearing mice, no antitumor effect was noted. DNA synthesis and/or lymphocyte proliferation is essential for the action of I-RNA in sensitizing lymphocytes, but not essential in the interaction of I-RNA-sensitized lymphocytes with TA. It appeared that, under the conditions used, the participation of host factors was essential in the latter interaction, since treatment of I-RNA-sensitized lymphocytes with TA in vitro was ineffective.