title: Autocrine pathways involving S100A8 and/or S100A9 that are postulated to regulate the immunological functions of macrophages in rats.
abstract: The development of ulcerative colitis (UC) is closely associated with abnormally functioning macrophages. Rat S100A8 (r-S100A8) and r-S100A9 (S100 proteins) is abundantly expressed in immune cells of myeloid origin, macrophages; however, it remains unclear why r-S100A9 is dominantly expressed in the macrophages of UC rats (UCR). The purpose of this study was to verify the immunological roles of S100 proteins in UCR. We observed the distribution of S100 protein-positive macrophages in the large colons of UCR using a fluorescent immunological staining method, so that S100 protein-positive macrophages were restricted to the rectal tissues of the UCR, and that the mRNA levels of r-S100A8 and r-S100A9 were up-regulated by stimulation with recombinant rat S100A8 (rr-S100A8) alone and rr-S100A9 alone, respectively. When the changes in the mRNA levels of r-S100A8 and r-S100A9 in macrophages were examined in in vitro study by PCR and real-time PCR, the mRNA levels of anti-inflammatory and inflammatory cytokines increased selectively after stimulation with rr-S100A8 alone and rr-S100A9 alone, respectively. These results suggest that autocrine signal transduction pathways involving S100 proteins regulate the immunological functions of macrophages to maintain homeostasis in the gastrointestinal tract. This may be depended on expression balance of S100 proteins in macrophages. It is strongly suggested that in UCR the immune functions of macrophages are regulated in a complex manner by r-S100A8 and/or r-S100A9 through undefined autocrine pathways on the cells.
authors.affiliation: Dept. of Clinical Laboratory Science, Faculty of Health Science, Tenri Health Care University, Nara 632-0018, Japan; Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
authors.forename: Kohki
authors.initials: K
authors.lastname: Okada
authors.affiliation: Immunological Laboratory, Diagnostic Division, Yamasa Shoyu Co. Ltd., Chiba 288-0056, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Arai
authors.affiliation: Dept. of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakase
authors.affiliation: Dept. of Clinical Laboratory Medicine, Tenri Hospital, Nara 632-8552, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kohno
authors.affiliation: Dept. of Clinical Laboratory Medicine, Tenri Hospital, Nara 632-8552, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Nakamura
authors.affiliation: Dept. of Clinical Laboratory Science, Faculty of Health Science, Tenri Health Care University, Nara 632-0018, Japan.
authors.forename: Mayu
authors.initials: M
authors.lastname: Takeda
authors.affiliation: Dept. of Clinical Laboratory Science, Faculty of Health Science, Tenri Health Care University, Nara 632-0018, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Toda
authors.affiliation: Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itoh
authors.affiliation: Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
authors.forename: Souichi
authors.initials: S
authors.lastname: Adachi
authors.affiliation: Dept. of Clinical Laboratory Science, Faculty of Health Science, Tenri Health Care University, Nara 632-0018, Japan. Electronic address: mikepon1308@tenriyorozu-u.ac.jp.
authors.forename: Masaki
authors.initials: M
authors.lastname: Ikemoto
mesh_terms: D000818:Animals; D001483:Base Sequence; D040501:Calgranulin A / Q000378:metabolism*; D040502:Calgranulin B / Q000378:metabolism*; D003093:Colitis, Ulcerative / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism; D017931:DNA Primers; D017737:Macrophages, Peritoneal / Q000276:immunology*; D008297:Male; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000378:metabolism; D012007:Rectum / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D040501:Calgranulin A; D040502:Calgranulin B; D016207:Cytokines; D017931:DNA Primers; D011994:Recombinant Proteins
keywords: Autocrine pathway; Inflammatory bowel disease; Macrophages; S100A8; S100A9