Immunomodulatory and Antioxidant Properties of a Novel Potential Probiotic Bacillus clausii CSI08

Abstract

Spore-forming bacteria of the <i>Bacillus</i> genus have demonstrated potential as probiotics for human use. <i>Bacillus clausii</i> have been recognized as efficacious and safe agents for preventing and treating diarrhea in children and adults, with pronounced immunomodulatory properties during several in vitro and clinical studies. Herein, we characterize the novel strain of <i>B. clausii</i> CSI08 (Munispore^®) for probiotic attributes including resistance to gastric acid and bile salts, the ability to suppress the growth of human pathogens, the capacity to assimilate wide range of carbohydrates and to produce potentially beneficial enzymes. Both spores and vegetative cells of this strain were able to adhere to a mucous-producing intestinal cell line and to attenuate the LPS- and Poly I:C-triggered pro-inflammatory cytokine gene expression in HT-29 intestinal cell line. Vegetative cells of <i>B. clausii</i> CSI08 were also able to elicit a robust immune response in U937-derived macrophages. Furthermore, <i>B. clausii</i> CSI08 demonstrated cytoprotective effects in in vitro cell culture and in vivo <i>C. elegans</i> models of oxidative stress. Taken together, these beneficial properties provide strong evidence for <i>B. clausii</i> CSI08 as a promising potential probiotic.