Evaluation of immunomodulatory effects of Lactobacillus rhamnosus R0011 fermented milk on production of pro-atherogenic cytokines: a comparison between THP-1 and U937 human monocyte cells (CCR4P.208)

Abstract

Abstract Atherosclerosis has been identified as an inflammatory disease involving both innate and adaptive immune activity. Fermented dairy product consumption has been associated with decreased cardiovascular disease incidence. The purpose of this study was to elucidate whether milk fermented with Lactobacillus rhamnosus R0011 influences production of pro-inflammatory cytokines by different human monocyte models (THP-1 and U937 human monocytes). THP-1 or U937 cells were stimulated with lipopolysaccharide (LPS) to incite an inflammatory response similar to that seen in atherosclerotic plaques. Monocytes were either co- or pre-incubated with milk fermented with L. rhamnosus R0011 or with milk controls and an LPS challenge and effects on the production of IL-8, sCD54, IL-1Ra were measured. sCD54 production by U937 monocytes was significantly reduced by co-incubation with the L. rhamnosus R0011 milk ferment or with acidified milk controls, which was not seen with THP-1 monocytes. IL-8 production was significantly increased in both U937 and THP-1 monocytes pre-incubated with unfermented milk controls followed by LPS stimulation. This increase in IL-8 production was not observed when U937 cells were pre-incubated with milk fermented with L. rhamnosus R0011 or with acidified controls. These results suggest that fermentation modifies milk components to influence production of IL-8 and sCD54 and that the effects of milk ferments on monocytes vary with the cell type used.