title: Cleaved Form of Osteopontin in Urine as a Clinical Marker of Lupus Nephritis.
abstract: We assessed the utility of two forms of osteopontin (OPN), OPN full and its cleaved form (OPN N-half), in plasma and urine as markers of disease activity in lupus nephritis (LN). Samples were collected from patients with systemic lupus erythematosus (SLE) (LN: N = 29, non-LN: N = 27), IgA nephropathy (IgAN) (N = 14), minimal change nephrotic syndrome (MCNS) (N = 5), diabetic nephropathy (DN) (N = 14) and healthy volunteers (HC) (N = 17). While there was no significant difference in urine OPN full concentration between groups, urine OPN N-half concentration was significantly higher in patients with LN than HC (p < 0.05). Moreover, urine OPN N-half was higher in LN patients with overt proteinuria (urine protein/creatinine ratio: P/C > 0.5) than LN patients with minimal proteinuria (P/C < 0.5, p < 0.0001), and also higher than in DN patients with overt proteinuria (P/C > 0.5, p < 0.01). Urine thrombin activity correlated with urine OPN N-half concentration (p < 0.0001), but not with urine OPN full concentration. These results suggest that urine OPN N-half concentration reflects renal inflammation. Thus, urine OPN N-half may be a novel disease activity marker for LN.
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Kitagori
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Yoshifuji
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Research Portfolio & Science, Astellas Pharma Inc., Tokyo, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Oku
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Research Portfolio & Science, Astellas Pharma Inc., Tokyo, Japan.
authors.forename: Chiyomi
authors.initials: C
authors.lastname: Sasaki
authors.affiliation: Department of Nephrology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Miyata
authors.affiliation: Department of Nephrology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Keita P
authors.initials: KP
authors.lastname: Mori
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Ohmura
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kawabata
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Department of Rheumatology and Clinical Immunology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Naoichiro
authors.initials: N
authors.lastname: Yukawa
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Imura
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kosaku
authors.initials: K
authors.lastname: Murakami
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Ran
authors.initials: R
authors.lastname: Nakashima
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Usui
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Department of Rheumatology and Clinical Immunology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Department of Nephrology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sakai
authors.affiliation: Department of Nephrology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Motoko
authors.initials: M
authors.lastname: Yanagita
authors.affiliation: Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Research Portfolio & Science, Astellas Pharma Inc., Tokyo, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Hirayama
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Tsuneyo
authors.initials: T
authors.lastname: Mimori
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood / Q000652:urine*; D003928:Diabetic Nephropathies / Q000378:metabolism; D005260:Female; D005922:Glomerulonephritis, IGA / Q000378:metabolism; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000378:metabolism*; D008181:Lupus Nephritis / Q000175:diagnosis* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009402:Nephrosis, Lipoid / Q000378:metabolism; D053495:Osteopontin / Q000097:blood / Q000652:urine*; D010446:Peptide Fragments / Q000097:blood / Q000652:urine*; D013917:Thrombin / Q000652:urine; D055815:Young Adult
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C506895:SPP1 protein, human; C582430:osteopontin (1-168), human; D053495:Osteopontin; D013917:Thrombin