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, ADRIAN; SOUZA NETO, FERNANDO; CAMPO, VALERIA; LEONI, JULIANA; GONZÁLEZ MAGLIO

Buenos Aires

Congreso; IV LASID. LXIII Argentinean Immunology Meeting. II French Argentinean Immunology Meeting.; 2015

Sociedad Argentina de Inmunologia

Abstract Inprevious work our laboratory has proven orally administered lipoteichoic acid(LTA) isolated from probiotic Lactobacillus rhamnosus GG to have anti-tumoraleffect against UV-induced skin tumors. Wehypothesize that dendritic cells (DCs) play a major role in this effect. Recentlywe showed that LTA can maturate bone marrow derived DCs increasing CD80/CD86and CD40 expression in vitro. The aim of the present study is to evaluate the amountand 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 of100 µg/ml LTA or PBS every other day and euthanized 24 hs after the lastadministration. Cells from LP, MLN and PP were obtained and stained withanti-CD11c, MHCII, CD40, CD86 antibodies as well as with 7AAD probe. The results obtained show a non-significant decreasein treated animals compared with controls in the percentage of viableCD11c+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. Therewas a possitive correlation between MHCII expression and the mean fluorescenceintensity (MFI) of both CD40 and CD86 in LP. On the other hand, we found anon-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 LTAon LP DCs and subsequent migration of these cells to PP and MLN. This could bepart of the mechanisms involved in the anti-tumoral effect of LTA. Keywords: Dendritic cells, lipoteichoic acid,Intestine immune system