Experimental study of the efficacy of combined use of cancer vaccine and interferon

To study in in vivo model the efficacy of combined scheme of administration of cancer vaccine (CV) and interferon (IFN). Lewis lung carcinoma (LLC) was transplanted to male C57Bl mice. For treatment, CV prepared from LLC cells with the use of cytotoxic lectins of B. subtilis B-7025, and preparation of murine IFN-alpha were used. Therapeutic effect was evaluated by measurement of tumor volume and analysis of average life span (ALS) of treated animals. Immunologic study included determination of antitumor cytotoxicity of T-lymphocytes (CTL) and natural killer (NK) cells by radiometric method, functional activity of peritoneal macrophages (MP) - by colorimetric test with nitroazole blue, and evaluation of titers of tumor necrosis factor (TNF) and interleukins-1 and -2 (IL-1, 2). It has been shown that the use of IFN preparation significantly elevated efficacy of vaccine therapy of solid form of LLC: duration of latent period of tumor growth elevated by 25%, ALS - by 28%, index of tumor growth inhibition - by 35-40%. Upon combined use of CV and IFN, significant activation of the cells - effectors of nonspecific immune defense (MP), and specific one (CTL) was observed. The obtained results evidence on perspectiveness of the development of combined schemes of administration of CV and IFN for elevation of the efficacy of vaccine therapy.