Probiotic and potential probiotic bacterial strains are routinely prescribed and used as supplementary therapy for a variety infectious diseases, including enteric disorders among a wide range of individuals. While there are an increasing number of studies defining the possible mechanisms of probiotic activity, a great deal remains unknown regarding the diverse modes of action attributed to these therapeutic agents. More precise information is required to support the appropriate application of probiotics. To address this objective, we selected two probiotics strains, Lactobacillus acidophilus MTCC-10307 (LA) and Bacillus clausii MTCC-8326 (BC) that are frequently prescribed for the treatment of intestinal disorders and investigated their effects on the RAW 264.7 murine macrophage cell line. Our results reveal that LA and BC are potent activators of both metabolic activity and innate immune responses in these cells. We also observed that LA and BC possessed similar activity in preventing infection simulated in vitro in murine macrophages by Salmonella typhimurium serovar enterica.
Keywords: Innate immunity; Macrophage; Pathogen; Probiotics.