Live and Heat-KilledLactobacillus rhamnosusATCC 7469 May Induce Modulatory Cytokines Profiles on Macrophages RAW 264.7

Abstract

This study aimed to evaluate the capacity ofLactobacillus rhamnosusand/or its products to induce the synthesis of cytokines (TNF-α, IL-1β, IL-4, IL-6, IL-10, and IL-12) by mouse macrophages (RAW 264.7). Three microorganism preparations were used: liveL.rhamnosus(LLR) suspension, heat-killedL.rhamnosus(HKLR) suspension, and the supernatant of a heat-killedL.rhamnosus(SHKLR) suspension, which were cultured with macrophages (37°C, 5% CO2) for 2 h and 30 min. After that, cells were cultured for 16 h. The supernatants were used for the quantitation of cytokines, by ELISA. The results were compared with the synthesis induced by lipopolysaccharide (LPS) and analysed, using ANOVA and Tukey test, 5%. LLR and HKLR groups were able to significantly increase the production of TNF-α, IL-6, and IL-10 (P<0.05). SHKLR also significantly increased the production of TNF-αand IL-10 (P<0.05) but not IL-6 (P>0.05). All theL.rhamnosussuspensions were not able to produce detectable levels of IL-1βor significant levels of IL-4 and IL-12 (P>0.05). In conclusion, live and heat-killedL.rhamnosussuspensions were able to induce the synthesis of different cytokines with proinflammatory (TNF-αand IL-6) or regulatory (IL-10) functions, suggesting the role of strainL.rhamnosusATCC 7469 in the modulation or in the stimulation of immune responses.