CONICET | Buscador de Institutos y Recursos Humanos

BackgroundProbiotics are increasingly being used in commercial animal production to advantageously influence intestinal microbiota functioning. In a previous work we obtained 129 isolates of lacic acid bacteria (LAB) from oat, alfalfa, rice, barley, wheat, sorghum, maize, white clover, ryegrass, sunflower, moha, Melilotus albus, Gatton panic and soy. In this work, the immunopotentiating capacity of 52 of those strains was determined in order to select the most promising ones for probiotic application.Methodology52 strains of LAB isolated from grass and forages were co cultured with murine macrophages (RAW 264.7). A total of 105 macrophages per well were co-cultured for 8 h with LAB cultures (18 h, 37°C, ratio 1:100). LPS (0.1 µg/ml) were used as activation control. IL-10 was measured in the supernatant by ELISA. In base on the induction of IL-10, some strains were selected and IL-1β, IL 12p70, IL 2, IL-6, IL-10, INF-γ and TNF-α were further quantified by MULTIPLEX ELISA.Results18 out of 52 LAB strains induced the highest amounts of IL-10. The selected strains belong to the species Lactobacillus plantarum, L. paracasei, Pediococcus pentosaceus, L. rhamnosus and Leuconostoc pseudomesenteroides. The co-culture supernatants of the selected strains, assayed by MULTIPLEX showed different capacity to induce TNF-α secretion, and a very low capacity to induce other proinflammatory cytokines (IL-1β, IL 12p70, IL-2, IL-6, or INF-γ).ConclusionThese results let us narrow down the number of LAB strains, from 52 to 3: Lactobacillus plantarum LpAv (oat), Lactibacillus paracasei LcAv (oat) and Pediococcus pentosaceus PpM (maize), based on their potential anti-inflammatory (IL 10) and epithelial barrier promotive (TNF-α) capacities.