Effect of Fructooligosaccharides (FOS) on the intestinal mucosal immune system against infection with S.Typhimurium

VELEZ, E.M.; PERDIGÓN, G.; MESON O.; CASTILLO N.; BIBAS BONET, M.E.

Buenos Aires

Congreso; First French-Argentine Immunology Congress LVIII Reunión Anual de la Sociedad Argentina de Inmunología, XIII Jornada Científica del Grupo Rioplatense de Citometría de Flujo; 2010

Sociedad Argentina de Inmunología

The FOS obtained from the roots of Yacon, used as a dietary supplement, can prevent enteric infections when given for a long term administration (30 days). Its effect is mediated by an increase in total secretory-IgA and does not produce increase of T cells. The aim of this study was to establish whether the FOS developes a preventive action against infection with S. Typhimurium by activating other mechanisms mediated by expression of receptors or cytokines produced by cells of the innate immune response. BALB/c mice were divided in 4 groups: normal control (NC), Basal (B ? 30 days with FOS), infection control (IC) and treated group (TG ? 30 days with FOS+ pathogen). At 7 days post challenge we studied: expression of TLR4, CD206, IL6, TNFalfa, IFNgamma and the expression of the chemokine MIP1alfa (Nº of + cells by IFI) from sections of small intestine, before and post challenge. MIP1alfa increase in TG with regard to IC group (25±4 vs 17±2), TNFalfa and IFNgamma had no significant difference between TG and IC group (23±3 vs 19±4 and 25±3 vs 19±5 respectively). The expression of IL6 increased in TG over the IC group (34±8 vs 19±2), the same effect was observed for receptors TLR4 and CD206 (24±2 vs 17±2 and 29±3 19±6, respectively). FOS protection against infection with S. Typhimurium would only be mediated by nonspecific immune response, with an increase in the expression of receptors (TLR4 and CD206) and IL6+ and MIP1alfa+ cells, that would favor immunological barrier mechanisms of innate immune response (phagocytosis and increased total secretory-IgA) against infection.