title: Probiotic Lactobacillus casei activates innate immunity via NF-kappaB and p38 MAP kinase signaling pathways.
abstract: Probiotic bacteria are microorganisms that benefit the host through improvement of the balance of intestinal microflora and possibly by augmentation of host defense systems. We examined the mechanisms for the up-regulation of innate immune responses by a probiotic Lactobacillus casei ATCC27139, in vivo. Using mouse models of systemic Listeria monocytogenes infection and MethA fibrosarcoma tumorigenesis in combination with BALB/c and SCID mice, we found that parenteral administration of L. casei ATCC27139 confers a protective effect against L. monocytogenes infection and anti-tumor activity against MethA fibrosarcoma by activation of innate immunity, while L. casei ATCC27139-J1R strains, which are J1 phage-resistant strains that have been selected from MNNG-treated clones, lacked these activities. Substantial differences between ATCC27139 and ATCC27139-J1R strains were observed in the capacity to induce innate cytokines such as TNF-alpha, IL-12, IL-18, and IFN-gamma, and pathogen-associated molecular pattern receptors, TLR2 and Nod2, by spleen cells. In addition, although phosphorylation of NF-kappaB p65 in spleen was equally enhanced in the ATCC27139- and the ATCC27139-J1R-treated groups, phosphorylation of both p38 MAPK and MAPKAPK-2 was significantly induced only by ATCC27139. Furthermore, inhibitors of NF-kappaB (sulfasalazine) and p38 MAPK (SB203580) significantly reduced cytokine production by the spleen cells of the mice treated with L. casei ATCC27139, suggesting that both NF-kappaB and p38 MAPK signaling pathways play important roles in the augmentation of innate immunity by the probiotic L. casei.
authors.affiliation: Department of Microbiology, School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
authors.forename: Yun-Gi
authors.initials: YG
authors.lastname: Kim
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Ohta
authors.forename: Takuya
authors.initials: T
authors.lastname: Takahashi
authors.forename: Akira
authors.initials: A
authors.lastname: Kushiro
authors.forename: Koji
authors.initials: K
authors.lastname: Nomoto
authors.forename: Teruo
authors.initials: T
authors.lastname: Yokokura
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Okada
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Danbara
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D005354:Fibrosarcoma / Q000276:immunology; D006358:Hot Temperature; D007113:Immunity, Innate; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D007780:Lacticaseibacillus casei / Q000502:physiology; D008089:Listeria monocytogenes; D008088:Listeriosis / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D050296:Microbial Viability; D016328:NF-kappa B / Q000276:immunology* / Q000378:metabolism; D009374:Neoplasms, Experimental / Q000276:immunology; D053473:Nod2 Signaling Adaptor Protein; D016511:Severe Combined Immunodeficiency; D015398:Signal Transduction; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D051195:Toll-Like Receptor 2 / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000276:immunology* / Q000378:metabolism
chemical_list: D016207:Cytokines; D047908:Intracellular Signaling Peptides and Proteins; D016328:NF-kappa B; D053473:Nod2 Signaling Adaptor Protein; C495945:Nod2 protein, mouse; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2; D048051:p38 Mitogen-Activated Protein Kinases