W206 - Evaluation of Potential Protective Effects of the Immunomodulatory Strains Lacticaseibacillus Rhamnosus UCO-25A and Limosilactobacillus Fermentum UCO-979C upon an Improved Model of Ulcerative Colitis

Apolinaria García Cancino – Full Professor, Department of Microbiology, Universidad de Concepción; Víctor Fuentes Barrera – PhD student, Department of Microbiology, Universidad de Concepción

Abstract Text: Ulcerative colitis has abruptly increased its incidence and prevalence, affecting millions of people. Current therapies aim to achieve long-term remission but are expensive, invasive and carry side effects as they are mainly based on the immunosuppression of the patient. Alternative therapies such as the use of probiotics modulating chronic inflammatory response or promoting the restoration of the intestinal epithelial barrier, have acquired great worldwide relevance as a strategy to prevent, treat, and achieve remission of the disease. There are various studies about the role of probiotics in the course and prevention of ulcerative colitis, whose promising results vary based on, among other factors: the selected probiotic strains or their combination, the study model used, the stage of the disease, and the form of administration. Therefore, this study evaluates the role of two probiotic strains Lacticaseibacillus rhamnosus UCO-25A and Limosilactobacillus fermentum UCO 979C, that have previously demonstrated an immunomodulatory capacity upon the innate immune response; for their application as a possible strategy to improve the management and evolution of ulcerative colitis. For this, an in vitro model of ulcerative colitis induced with sodium dextran sulfate in Caco-2 cells, grown on an extracellular matrix membrane from the small intestine submucosa, was used to achieve an improved approximation of the disease. After co-cultures with the bacterial strains, a modulation of the immune response was observed through the variation of different inflammatory markers in the cells, indicating a clear effect of the probiotic strains upon the improved disease model.