The Efect of Probiotic Lactobacilli and Alginite on the Cellular Immune Response in Salmonella Infected Mice

Alginite is organic matter rich in humic substances and commonly found in nature, but despite that, the knowledge of its biological effects is limited. In our study we focused on monitoring the effects of alginite alone, as well as its effect as a carrier of probiotic lactobacilli on the cellular immune response in SPF mice after infection with Salmonella Typhimurium. Sixty six conventional SPF female mice of the Balb/c line were divided into 4 groups: 1. infection free negative control (NK) supplied neither alginite nor probiotic lactobacilli in the feed; 2. infection free alginite control (Alg) supplied feed with 10 % alginite; infected control supplied alginite in the feed but no lactobacilli; 3. infectious control (Alg + Sal) - animals infected with salmonella and supplied 10 % alginite in the feed but no lactobacilli;and 4. probiotic group (Lab + Alg + Sal) - animals infected with salmonella and administered 10 % alginite and Lactobacillus reuteri 2/6 in the feed. On day 21 of the experiments, the mice were bled and their mesenteric lymph nodes were taken after their death. The peripheral blood of the mice was analysed for the activity of phagocytes and the percentage of selected lymphocyte subpopulations was determined in the mesenteric lymph nodes and blood. The significantly highest phagocytic activity (FA) was noted in the infected group with alginite (Alg + Sal). The FA was significantly increased in groups Alg and Lab + Alg + Sal in comparison with the NK group. The highest engulfing ability of phagocytes (phagocytic index) was observed in the Lab + Alg + Sal group in comparison with other groups, but also in Alg group in comparison with NK. In the Lab + Alg + Sal group, we observed a significantly higher percentage of B-lymphocytes, CD4⁺CD8⁺ and natural killer T cells (NKT), but more significant impact on the numbers of subpopulations of lymphocytes was observed in the mesenteric lymph nodes, with the significantly highest proportions of CD4⁺CD8⁺lymphocytes and NK and NKT cells. Our results indicated immunomodulatory properties of alginite and L. reuteri 2/6 in salmonella infected mice, especially at the level of the innate immune system components. This activation of phagocytosis and NK cells can be used in the treatment of various infections.