[Effect of exogenous RNA preparations on the antitumor activity of the splenocytes in C3HA mice]

Tumor growth inhibition was compared in animals implanted a mixture of tumor cells and splenocytes, treated or non-treated with RNA preparations. The latter were isolated from the spleens of C3ha mice, both intact (control--cRNA) and immunized with normal tissues of syngeneic or allogeneic animals (immune--imRNA). Examination of various samples of splencytes of intact C3HA mice show that treatment with cRNA and imRNA preparations changes occasionally their antitumor activity in relation to MGXXIIa hepatoma cells. In the majority of the experiments effects of cRNA and imRNA on splenocytes were unidirectional. Molecular and cellular mechanisms of this phenomenon are discussed.