title: Increased production of cytotoxic macrophage progenitors by Lactobacillus casei in mice.
abstract: Heat-killed Lactobacillus casei YIT9018 (LC9018), when administered intravenously to normal mice, induced increase in Mac-1+ cells and Mac-2+ cells but not in Mac-3+ cells in spleen. The number of both populations changed in the same time course and was maximal 14 d after the administration. To know the effect of LC9018 on hematopoietic progenitor level, we examined the number of macrophage colony-forming cells (M-CFC), granulocyte-macrophage CFC (GM-CFC), and colony-forming units in spleen (CFU-S) in bone marrow 3 d after the administration. LC9018 stimulated the proliferation of M-CFC but not that of GM-CFC and CFU-S. LC9018-induced M-CFC were similar to normal M-CFC in dependence on macrophage colony-stimulating factor (M-CSF) and buoyant density. M-CFC-derived macrophages cultured in the presence of M-CSF expressed Mac-1 and Mac-2 but not Mac-3. They showed cytotoxic activity against syngenic tumor cells, Meth A, via direct contact, when assayed by using an in vitro colony inhibition assay or an in vivo Winn test. These results indicate that LC9018 stimulates the proliferation of cytotoxic macrophage progenitors in bone marrow and induces their differentiation in spleen. These effects may be one of the ways in which LC9018 suppresses tumor growth.
authors.affiliation: Yakult Central Institute for Microbiological Research, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Nanno
authors.forename: T
authors.initials: T
authors.lastname: Shimizu-Takeda
authors.forename: A
authors.initials: A
authors.lastname: Mike
authors.forename: M
authors.initials: M
authors.lastname: Ohwaki
authors.forename: Y
authors.initials: Y
authors.lastname: Togashi
authors.forename: R
authors.initials: R
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Kumagai
authors.forename: M
authors.initials: M
authors.lastname: Mutai
mesh_terms: D000276:Adjuvants, Immunologic / Q000276:immunology*; D000818:Animals; D000943:Antigens, Differentiation / Q000378:metabolism; D001853:Bone Marrow / Q000187:drug effects / Q000382:microbiology; D001854:Bone Marrow Cells; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003115:Colony-Stimulating Factors / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic; D037502:Galectin 3; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology / Q000382:microbiology; D007780:Lacticaseibacillus casei / Q000276:immunology*; D008262:Macrophage Activation / Q000187:drug effects; D016177:Macrophage-1 Antigen; D008264:Macrophages / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000382:microbiology
chemical_list: D000276:Adjuvants, Immunologic; D000943:Antigens, Differentiation; D003115:Colony-Stimulating Factors; D037502:Galectin 3; D016177:Macrophage-1 Antigen; C036763:monocyte-macrophage differentiation antigen