EFFECT OF L. CASEI CRL 431 AND ITS CELLULAR WALL ON THE THYMUS AT DIFFERENT AGES IN A MICE MODEL

BALCELLS MARÍA FLORENCIA; IVANNA NOVOTNY NUÑEZ; GABRIELA PERDIGÓN; CAROLINA MALDONADO GALDEANO

Mar del Plata

Congreso; LXVI Reunión Anual de la Sociedad Argentina de Inmunología (SAI); 2018

Sociedad Argentina de Inmunología (SAI)

Thymus is responsible of ontogeny and maturation of T lymphocytes, however, it begins to regress with time.Aim: to study the effect of L. casei 431 and/or its cell wall in the thymus at different ages.BALB/c mice were divided into groups of age: 21, 28, 45, 90 and 180 days(d), which were subdivided according to the supplement received: Normal control(NC) received the conventional balanced diet and water ad libitum; Lactobacillus casei(Lc) group received the conventional balanced diet and oral suspension of probiotic bacteria. Mice were sacrificed at the corresponding age. Initial and final weight of the animal, weight of the thymus was taken. Samples were: large intestine for microbiota analysis, serum(S), small intestinal fluid(IF) and thymus for cytokine analysis (IFNγ, IL-6, IL-10, IL-12 p70, TNFα, IL-3). Cytokines determination in culture supernatant of thymus stimulated with the bacteria (B) or its cell wall (W). Lymphocyte population in thymus and in mesenteric lymph nodes (MLN) were analyzed by flow cytometry.Results: probiotic supplementation increased body weight in all groups of age. Body weight/thymus ratio decreased at 28, 45 and 90d in Lc. Supplementation showed decreased population of enterobacteria and increased population of lactobacilli, without significant differences between NC and Lc in the total anaerobic population.Cytokines in cell culture supernatant showed a decrease in IFNγ and TNFα, increased values of IL-10, IL-12 and IL-3, IL-6 values were near to NC in TB and Lc. Decreases in the CD4+ population in thymus showed in Lc group at 45d and significantly increased at 90d respect to NC. In NC CD4+/CD8+ ratio a significant increase at 90d (p