L. delbrueckii subsp lactis (CIDCA 133) stimulates murine macrophages infected with C. rodentium.

HUGO, A.A.; ROLNY, I.S.; ROMANIN, D.; PEREZ, P.F.

Los Cocos, Córdoba

Congreso; LXI Reunion Anual de la Sociedad Argentina de Inmunología; 2013

Sociedad Argentina de Inmunología

Lactobacilli probiotic strains contribute to the balance of the intestinal microbiota and they also stimulate the immune system. Macrophages play a key role in inflammation and host defense. In this work we evaluate the stimulatory capacity of L. delbrueckii subsp lactis (CIDCA 133) to the murine macrophage cell line Raw 264.7 infected with C. rodentium. Cells were incubated with FITC-labeled bacteria at different multiplicities of infection (moi). The endocytic capacity was evaluated by flow cytometry using trypan blue as quenching solution. Surface co-stimulatory molecules (CD86 and MHC II) and TLR-2 were determined by flow cytometry. NO2 production was evaluated with the Griess reaction. The expression of iNOS was measured by flow cytometry. ROS production was determined by fluorescence microscopy by using CM-H2DCFDA. Internalization of C. rodentium correlated with the moi. When macrophages were co-incubated with strain 133 the percentage of FICT positive cells significantly increased. The expression levels of the CD 86, MHC II and TLR-2 were high in the presence of C. rodentium. Cells incubated with lactobacilli expressed basal levels of all molecules. When C. rodentium and strain 133 were assayed together there was a 1.5 fold increase of CD86 and MHC II expression after 48 h but expression of TLR-2 remained constant. The production of NO2 was unaffected by lactobacilli but the incubation of the macrophages with C. rodentium determined a statistic significant increase of NO2 levels. The co-incubation of macrophages with both strains resulted in a 2 fold increased in NO2 concentration. The iNos expression correlated with the production of NO2. Strain 133 and C rodentium (at moi 100:1) induced a significantly increased in ROS. When cells were incubated with both strains there was a significantly induction of ROS at moi 20:1. Results show that strain CIDCA 133 is able to enhance the phagocytic capacity and the activity of Raw cells infected with C. rodentium.