Lactobacillus reuteri CRL1098 soluble factors modulate tumor necrosis factor alpha production in peripheral blood mononuclear cells: involvement of lipid rafts.

MECHOUD, M.; MATEOS, M. ; FONT DE VALDEZ, G.; VILLENA, J.; SALVADOR, G. ; RODRIGUEZ, A.

INTERNATIONAL IMMUNOPHARMACOLOGY

ELSEVIER SCIENCE BV

Año: 2012 p. 443 - 456

1567-5769

The aim of the present study was to evaluate the capacity of Lactobacillus reuteri CRL1098 soluble factors (Lr-S) to modulate TNF-alpha production in peripheral blood mononuclear cells (PBMC) and to study lipid rafts participation in this response. PBMC treated with Lr-S showed a reduced production of TNF-alpha. In addition, Lr-S treatment activated ERK and p38 MAPK pathways in PBMC. Lipid rafts participation in the reduced production of TNF-alpha by PBMC induced by Lr-S was verified by lipid rafts disruption with methyl-alpha-cyclodextrin and the reduction of the Src-tyrosine kinase Lck localization in rafts. Moreover, PBMC pre-treatment with Lck inhibitors blocked the effect of Lr-S on TNF-alpha production suggesting that activation and movilization of Lck from lipid rafts would be involved in the modulatory effect of L. reuteri CRL1098. A secreted peptide of 5,785 Da would be responsible of the modulatory effect of CRL1098 strain. This study demonstrated for the first time the lipid rafts participation in a response induced by a beneficial bacterium. Also, these results open new possibilities for investigating the molecular mechanisms involved in the interaction of probiotic bacterial extracellular compounds with immune cells.