In vitro Modeling of the Effect of Lactobacillus Metabolites on the Systemic Response of the Body in Intestinal Viral Infection

Background. Viral infectious diseases remain a significant cause of morbidity and mortality worldwide. The lack of effective antiviral drugs for the treatment of viral gastroenteritis emphasizes the relevance of various forms of combination therapy, including a balanced diet and the use of probiotics. Objective. To verify in vitro the hypothesis about the effect of metabolites from probiotic strains of lactobacilli on the systemic response of the body in intestinal viral infection. Methods. The objects of study were filtrates of culture fluids from probiotic lactobacillus strains L. delbrueckii subsp. lactis LE and L. rhamnosus LB3. HEp-2 and Namalwa cell cultures and vesicular stomatitis test virus were used as biological test objects. The study employed spectrophotometric and cytofluorometric analysis. Results. The absence of a direct anti-inflammatory effect in the samples of lactobacillus culture fluid filtrates was revealed. It was found that the culture fluid filtrate of the lactobacillus strain L. delbrueckii subsp. lactis LE exhibited the most pronounced properties of an interferon coinducer. The proliferative index (PI) of HEp-2 cells was analyzed under different effects. Cells incubated with lactobacillus culture fluid filtrate (LE) showed an increase in PI for young cells, a decrease for mid-mature cells, and an increase for late-mature cells. The combined effect of TNF-a and lactobacillus LE culture filtrate was characterized by stimulation of PI for medium-mature cells and significant inhibition of PI of late-mature cells. Conclusions. The synergistic effect of lactobacillus culture filtrates and inflammatory factors will contribute to the accelerated elimination of late-mature and affected cells from the intestine and stimulate the proliferation of young and medium-mature cells to replace them, thereby promoting the regeneration of the intestinal epithelium and accelerate recovery. At the same time, probiotic strains of lactobacilli can enhance the interferonogenic properties of gastroenteritis viruses, and ultimately stimulating the formation of specific immunity in these diseases.