EFFECTS OF ORALLY ADMINISTRED LIPOTEICHOIC ACID PURIFIED FROM LACTOBACILLUS RHAMNOSUS GG ON DENDRITIC CELLS IN MOUSE LAMINA PROPRIA, MESENTERIC LYMPH NODES AND PEYER PATCHES

FRIEDRICH AD; SOUZA NETO F; CAMPO V; LEONI J; GONZÁLEZ MAGLIO DH; PAZ ML

CABA

Congreso; I meeting LASID FAIC SAI; 2015

Sociedad Argentina de Inmunología

In previous work our laboratory has proven orally administered lipoteichoic acid (LTA) isolated from probiotic Lactobacillus rhamnosus GG to have anti-tumoral effect against UV-induced skin tumors. We hypothesize that dendritic cells (DCs) play a major role in this effect. Recently we showed that LTA can maturate bone marrow derived DCs increasing CD80/CD86 and CD40 expression in vitro. The aim of the present study is to evaluate the amount and phenotype of DCs in mouse lamina propria (LP), mesenteric lymph nodes (MLN) and Peyers? Patches (PP) after LTA oral administration.Adult Balb/c mice were administered with 8 doses of 100 µg/ml LTA or PBS every other day and euthanized 24 hs after the last administration. Cells from LP, MLN and PP were obtained and stained with anti-CD11c, MHCII, CD40, CD86 antibodies as well as with 7AAD probe. The results obtained show a non-significant decrease in treated animals compared with controls in the percentage of viable CD11c+MHCIIlow (1.86±0.4% vs. 2.76±0.56%), CD11c+MHCIImid (0.91±0.37% vs. 1.30±0.13%) and CD11c+MHCIIhigh (0.45±0.19% vs. 0.96±0.52%) cells in LP. There was a possitive correlation between MHCII expression and the mean fluorescence intensity (MFI) of both CD40 and CD86 in LP. On the other hand, we found a non-significant increase CD11c+MHCIIhigh cells in PP (2.13±1.13% vs 1.62±0.78%) and MLN (3.37±1.37% vs. 2.45±0.89%). Our results could be explained by the effects of LTA on LP DCs and subsequent migration of these cells to PP and MLN. This could be part of the mechanisms involved in the anti-tumoral effect of LTA.