B. ANIMALIS AND THE LECTIN OF B. SUBTILIS DIFFERENTLY REGULATE CYTOKINES PRODUCTION IN TUMOUR-BEARERS

By producing a variety of soluble factors, including cytokines, macrophages (Mph) modulate the activity of other immune cells and have direct effects on cancer cells. This makes Mph a promising target for cancer immunotherapy. Aim. This work purposed to study the effect of the simultaneous use of B. animalis and the lectin of B. subtilis on the production of some cytokines by Mph in tumour -bearing mice. Materials and methods. Female Balb/c mice bearing solid Ehrlich adenocarcinoma (SEA) were treated with the lectin (s/c, 1 mg/kg body weight) or B. animalis (per os, 7×105 CFU/mouse) or with their combination. The lectin was isolated from the cultural fluid of B. subtilis ІМV В-7724. Lyophilized cells of B. animalis subsp. lactis BB-12 (Lek Pharmaceuticals, Slovenia) was used as a probiotic. On day 28 of tumour growth, Mph from the peritoneal cavity (pMph) and tumour nodule (tMph) were isolated and analyzed for TNF-α and IL-10 production. Results. The pMph and tMph of untreated mice produced low levels of TNF-α (739.8 and 800.4 pg/mL respectively) and high levels of IL-10 (1169.8 and 1090.5 pg/mL respectively), the TNF-α/IL-10 ratio was 0.68 and 0.95 respectively. The lectin improved the TNF-α/IL-10 ratio to 1.13 (in the intact mice, it was 1.11). In the combined group, the effect was similar but less profound. The results of the B. animalis group did not differ from the untreated SEA group. Conclusions. The changes in the production levels of cytokines indicate the lasting preservation of Mph functional activity in the tumour -bearers due to the influence of probiotics or their metabolites.