In vivo administration of Enterococcus faecalis CECT7121 and its immunomodulatory effects

MOLINA MA; DÍAZ AILÉN; BEROD L; SPARWASSER TD; CASTRO MS; MANGHI MA

Los Cocos,Córdoba

Congreso; Reunión Anual de la SAI; 2013

Sociedad Argentina de Inmunología

Over the past years, our group has studied the immunomodulatory effects of E. faecalis (Ef) CECT7121. This bacterium prevents Salmonella infection, modulates the immune response generated after DTPw vaccination, protects against a T cell lymphoma, and interferes with the development of an allergic disease. All these murine models showed a Th1-type immune response, suggesting that this probiotic may modulate the immune system towards a local and/or systemic increment of IFNg production. The aim of this work was to elucidate the mechanisms triggered after intragastric (ig) treatment with Ef CECT7121. To this end, 2 different groups of BALB/c mice were ig treated either with PBS or live Ef CECT7121 (EF) during 3 consecutive days; half of each group was sacrificed at day 4 after the last ig inoculation, while the rest was analyzed 11 days post-challenge. Spleen and mesenteric lymph node cells were cultured for 72 h in the presence of culture medium, ConA, and heat-killed Ef CECT7121 (hkEf). Cell proliferation was assessed by 3H-thymidine uptake and different cytokines were measured in culture supernatants by ELISA. Our results show that Ef CECT7121 induces an immunostimulatory effect in mice, increasing systemic T cell proliferation as demonstrated by ConA stimulation of spleen cells at day 11 (*p