THE INFLUENCE OF BIFIDOBACTERIUM ANIMALIS AND LECTIN OF B. SUBTILIS IMV B-7724 ON THE ANTITUMOR IMMUNE RESPONSE OF MICE WITH EHRLICH ADENOCARCINOMA.

Abstract

Aim: To investigate the effect of bacteria of the genus Bifidobacterium and the extracellular metabolite of B. subtilis IMV B-7724 on the antitumor immune response of mice with a model tumor.

Materials and methods: The study was conducted on Balb/c mice with transplanted solid Ehrlich adenocarcinoma (ACE). Starting from the 2nd day after the transplantation of tumor cells, the animals of the experimental groups were treated with lectin of B. subtilis IMV B-7724 (s/c, 1 mg/kg of weight), Bifidobacterium animalis (per os, 7 × 105 CFU/mouse) or their combination. The immunological studies were performed on the 21st and 28th days of tumor growth. The functional activity of natural killer cells (NK), cytotoxic T-lymphocytes (CTL), as well as the ability of lymphocytes from the peripheral lymph nodes (PLN) to transform into blast cells under the influence of T- (Con A) and B-cell (LPS) mitogens were determined.

Results: Administration of probiotic components to the mice with ACE led to the activation of innate immune responses, that is, to a significant increase in the cytotoxic activity of NK, especially in the case of their combined use. The NK cytotoxicity index was higher than that in the non-treated ACE-bearing mice and the intact control by 3.7 and 2.1 times, respectively (p < 0.05). Similarly, the highest specific cytotoxic activity of spleen lymphocytes was observed upon the combined use of the microbial preparations: the CTL cytotoxicity index was nearly 2.5-fold higher than in the non-treated ACE-bearing mice. The data on the ability of PLN lymphocytes to transform into blast cells under the influence of Con A and LPS indicated the preservation of the functional activity of lymphocytes in the animals of the experimental groups during ACE growth.

Conclusion: Both B. animalis and lectin of B. subtilis IMV B-7724 have a significant influence on the effectors of the natural and adaptive immunity of mice with ACE. Their combined use was found to be the most effective.