OBJECTIVE: To compare the expression of galectin 9 (Gal-9) in synovial tissue (ST) from rheumatoid arthritis (RA) patients and osteoarthritis (OA) patients and to evaluate the effects of Gal-9 on fibroblast-like synoviocytes (FLS) in these patients. METHODS: The expression of Gal-9 in ST and FLS was compared using immunohistochemical techniques. Apoptotic cells in RA and OA ST samples were detected by TUNEL assay. Apoptosis of FLS was analyzed by the sub-G(1) method in vitro. The in vivo suppressive effects of Gal-9 on collagen-induced arthritis (CIA) in a mouse model were also elucidated. RESULTS: The percentage of Gal-9-positive cells in ST samples and the amount of Gal-9 in synovial fluid samples were significantly higher in patients with RA than in patients with OA, suggesting the involvement of Gal-9 in the development of RA. Compared with the 2 wild-type Gal-9 forms, stable Gal-9, a mutant protein resistant to proteolysis, significantly induced apoptosis of FLS from RA patients. In contrast, other galectins, such as Gal-1, Gal-3, and Gal-8, did not induce apoptosis or suppress the proliferation of human RA FLS. Stable Gal-9 preferentially induced apoptosis and suppressed the proliferation of RA FLS in vitro. It also induced apoptosis of cells in RA ST implanted into SCID mice in vivo. In a mouse model of CIA, apoptotic cells were detected in the joints of stable Gal-9-treated mice, but not phosphate buffered saline-treated mice, and suppressed CIA characterized by pannus formation with inflammatory cell infiltration and bone/cartilage destruction. CONCLUSION: Gal-9-induced apoptosis of hyperproliferative RA FLS may play a critical role in the suppression of RA.
OBJECTIVE: To compare the expression of galectin 9 (Gal-9) in synovial tissue (ST) from rheumatoid arthritis (RA) patients and osteoarthritis (OA) patients and to evaluate the effects of Gal-9 on fibroblast-like synoviocytes (FLS) in these patients. METHODS: The expression of Gal-9 in ST and FLS was compared using immunohistochemical techniques. Apoptotic cells in RA and OA ST samples were detected by TUNEL assay. Apoptosis of FLS was analyzed by the sub-G(1) method in vitro. The in vivo suppressive effects of Gal-9 on collagen-induced arthritis (CIA) in a mouse model were also elucidated. RESULTS: The percentage of Gal-9-positive cells in ST samples and the amount of Gal-9 in synovial fluid samples were significantly higher in patients with RA than in patients with OA, suggesting the involvement of Gal-9 in the development of RA. Compared with the 2 wild-type Gal-9 forms, stable Gal-9, a mutant protein resistant to proteolysis, significantly induced apoptosis of FLS from RA patients. In contrast, other galectins, such as Gal-1, Gal-3, and Gal-8, did not induce apoptosis or suppress the proliferation of human RA FLS. Stable Gal-9 preferentially induced apoptosis and suppressed the proliferation of RA FLS in vitro. It also induced apoptosis of cells in RA ST implanted into SCIDmice in vivo. In a mouse model of CIA, apoptotic cells were detected in the joints of stable Gal-9-treated mice, but not phosphate buffered saline-treated mice, and suppressed CIA characterized by pannus formation with inflammatory cell infiltration and bone/cartilage destruction. CONCLUSION:Gal-9-induced apoptosis of hyperproliferative RA FLS may play a critical role in the suppression of RA.
Authors: John A Mengshol; Lucy Golden-Mason; Tomohiro Arikawa; Maxwell Smith; Toshiro Niki; Ryan McWilliams; Jessica A Randall; Rachel McMahan; Michael A Zimmerman; Manu Rangachari; Evgenia Dobrinskikh; Pierre Busson; Stephen J Polyak; Mitsuomi Hirashima; Hugo R Rosen Journal: PLoS One Date: 2010-03-04 Impact factor: 3.240
Authors: Shravan Madireddi; So-Young Eun; Amit K Mehta; Aruna Birta; Dirk M Zajonc; Toshiro Niki; Mitsuomi Hirashima; Eckhard R Podack; Taylor H Schreiber; Michael Croft Journal: J Immunol Date: 2017-09-06 Impact factor: 5.422
Authors: Asif J Iqbal; André L F Sampaio; Francesco Maione; Karin V Greco; Toshiro Niki; Mitsuomi Hirashima; Mauro Perretti; Dianne Cooper Journal: Am J Pathol Date: 2011-03 Impact factor: 4.307