title: Expression of SPARC by activated hepatic stellate cells and its correlation with the stages of fibrogenesis in human chronic hepatitis.
abstract: Secreted protein, acidic and rich in cysteine (SPARC), which functions in tissue remodeling, has been reported to be expressed by myofibroblasts in liver cirrhosis and hepatocellular carcinoma. This study aimed to reveal its expression in chronic hepatitis. Immuno-light and electron microscopy demonstrated that SPARC was expressed by nerve fibers and hepatic stellate cells (HSCs) in the liver parenchyma and myofibroblasts in the fibrous septa. Reaction products were localized in the rough endoplasmic reticulum and nuclear envelope. Serial section analysis demonstrated that SPARC, platelet-derived growth factor receptor-beta, and alpha-smooth muscle actin were co-expressed by HSCs. Quantitative analysis demonstrated that, while SPARC-positive HSCs were sparse in control livers, they significantly increased in number in the livers with chronic hepatitis. There were, however, no significant differences in number among the grades of activity, the stages of fibrosis, or etiology (virus-infected or autoimmune, hepatitis B virus or hepatitis C virus). In liver cirrhosis, however, they significantly decreased in number. The present results indicate that SPARC is expressed by activated HSCs in chronic hepatitis, suggesting the involvement of SPARC in hepatic fibrogenesis after chronic injuries.
authors.affiliation: Department of Anatomy, Osaka City University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-ku, Osaka 545-8585, Japan. kazuki@med.osaka-cu.ac.jp
authors.forename: Kazuki
authors.initials: K
authors.lastname: Nakatani
authors.forename: Shuichi
authors.initials: S
authors.lastname: Seki
authors.forename: Norifumi
authors.initials: N
authors.lastname: Kawada
authors.forename: Takuya
authors.initials: T
authors.lastname: Kitada
authors.forename: Takao
authors.initials: T
authors.lastname: Yamada
authors.forename: Hiroki
authors.initials: H
authors.lastname: Sakaguchi
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kadoya
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ikeda
authors.forename: Kenji
authors.initials: K
authors.lastname: Kaneda
mesh_terms: D000199:Actins / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D002452:Cell Count; D006521:Hepatitis, Chronic / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D007728:Kupffer Cells / Q000378:metabolism* / Q000648:ultrastructure; D008099:Liver / Q000294:innervation / Q000473:pathology; D008103:Liver Cirrhosis / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D008854:Microscopy, Electron; D009412:Nerve Fibers / Q000378:metabolism / Q000473:pathology; D015388:Organelles / Q000378:metabolism / Q000648:ultrastructure; D015676:Osteonectin / Q000378:metabolism*; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000378:metabolism
chemical_list: D000199:Actins; D015415:Biomarkers; D015676:Osteonectin; D020797:Receptor, Platelet-Derived Growth Factor beta