title: The potential role of Osteopontin in the maintenance of commensal bacteria homeostasis in the intestine.
abstract: Osteopontin (Opn), a multifunctional extracellular matrix protein, is implicated in the pathogenesis of various inflammatory disorders. Under physiologic conditions, its expression is restricted to certain tissues including bone and kidney tubule. However, cellular activation during disease development induces Opn expression in various immune cells. In this study, using Opn-EGFP knock-in (KI) mice we found that CD8α+ T cells in the intestinal tissues, including Peyer's patch, lamina propria and epithelium, express Opn under steady state conditions. Therefore, we examined the role of Opn-expressing CD8α+ T cells in intestinal homeostasis. Interestingly, Opn knockout (KO) mice had altered fecal microflora concordant with a reduction of TCRγδ+ intraepithelial lymphocytes (IELs). Consistent with this result, both treatment with anti-Opn blocking antibody and deficiency of Opn resulted in decreased survival of TCRγδ+ and TCRαβ+ IELs. This data suggests that a possibility that Opn may function as a survival factor for IELs in the intestinal tissue. Collectively, these data suggest the possibility that Opn might regulate the homeostasis of intestinal microflora through maintenance of TCRγδ+ IELs, possibly by support of IEL survival.
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.|Department of Immunobiology, Institute of Development, Ageing, and Cancer, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan.
authors.forename: Koyu
authors.initials: K
authors.lastname: Ito
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Nakajima
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Fukushima
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Department of Immunology and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Sakamoto
authors.affiliation: Department of Immunology and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Hamazaki
authors.affiliation: Department of Immunobiology, Institute of Development, Ageing, and Cancer, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan.
authors.forename: Kouetsu
authors.initials: K
authors.lastname: Ogasawara
authors.affiliation: Department of Immunology and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Nagahiro
authors.initials: N
authors.lastname: Minato
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Hattori
mesh_terms: D000818:Animals; D018407:Bacterial Physiological Phenomena; D020869:Gene Expression Profiling; D006706:Homeostasis / Q000502:physiology*; D007422:Intestines / Q000382:microbiology*; D051379:Mice; D008822:Mice, Transgenic; D053495:Osteopontin / Q000502:physiology*
chemical_list: D053495:Osteopontin