title: Growth Arrest-Specific 6 Protein in Patients with Sjögren Syndrome: Determination of the Plasma Level and Expression in the Labial Salivary Gland.
abstract: OBJECTIVE
  Growth arrest-specific protein 6 (Gas6) is a vitamin K-dependent protein expressed by endothelial cells and leukocytes that are involved in cell survival, migration, and proliferation in response to inflammatory processes. The aim of this study was to assess the implications of Gas6 in Sjögren syndrome (SS) and its expression in the labial salivary gland.
  
  
  RESULTS
  A total of 254 adults, including 159 with primary Sjögren syndrome (pSS), 34 with secondary Sjögren syndrome (sSS), and 61 normal controls, were recruited. Plasma Gas6 concentrations were determined, and Gas6 expressions in labial salivary gland (LSG) tissues from controls and pSS and sSS patients were also evaluated. Plasma Gas6 concentrations were significantly lower among patients with pSS than normal controls (13.5 ± 8.6 vs. 19.9 ± 13.4 ng/ml, p < 0.001). There were, however, no significant differences in plasma Gas6 levels between pSS and sSS patients (13.5 ± 8.6 vs. 16.9 ± 11.2 ng/ml, p = 0.068). In multivariate logistic regression analysis, after adjustment for white blood cell count, hemoglobin level, platelet count, lymphocyte count, and C3 and C4 levels, lower plasma Gas6 concentrations were significantly associated with an increased risk of SS. Moreover, by using a semi-quantitative scale to evaluate Gas6 expression in LSG tissues, Gas6 expression was found to be markedly lower in LSG tissues from pSS patients than in tissues from normal controls.
  
  
  CONCLUSIONS
  Decreased plasma Gas6 concentration and LSG expression were associated with pSS. As such, Gas6 may represent a novel independent risk factor for pSS, with a potential role in salivary gland inflammation and dysfunction.
authors.affiliation: Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan; Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, School of Medicine, Tzu Chi University, Hualien, Taiwan; Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Chen-Hung
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Hsiang-Cheng
authors.initials: HC
authors.lastname: Chen
authors.affiliation: Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan; Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Chi-Ching
authors.initials: CC
authors.lastname: Chang
authors.affiliation: Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Yi-Jen
authors.initials: YJ
authors.lastname: Peng
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Chien-Hsing
authors.initials: CH
authors.lastname: Lee
authors.affiliation: School of Dentistry, National Defense Medical Center, Department of Oral Diagnosis and Pathology, Tri-Service General Hospital, Taipei, Taiwan.
authors.forename: Yi-Shing
authors.initials: YS
authors.lastname: Shieh
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Yi-Jen
authors.initials: YJ
authors.lastname: Hung
authors.affiliation: Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan; Division of Nephrology, Department of Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.
authors.forename: Yuh-Feng
authors.initials: YF
authors.lastname: Lin
mesh_terms: D016022:Case-Control Studies; D003176:Complement C3 / Q000032:analysis; D003181:Complement C4 / Q000032:analysis; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis / Q000097:blood*; D007958:Leukocyte Count; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D012469:Salivary Glands / Q000737:chemistry* / Q000378:metabolism; D012859:Sjogren's Syndrome / Q000097:blood* / Q000378:metabolism; D000099255:Growth Arrest-Specific Protein 6
chemical_list: D003176:Complement C3; D003181:Complement C4; D006454:Hemoglobins; D036341:Intercellular Signaling Peptides and Proteins; D000099255:Growth Arrest-Specific Protein 6