title: Increased serum amyloid A and its association with autoantibodies, acute phase reactants and disease activity in patients with rheumatoid arthritis.
abstract: Determination of disease activity in patients with rheumatoid arthritis (RA) has become an important component for RA management. The aim of the present study was to investigate the association between circulating levels of serum amyloid A (SAA) and disease activity in RA patients. The types of disease and the respective number of patients enrolled in the present study were as follows: RA, 88; osteoarthritis (OA), 54; systemic lupus erythematosus (SLE), 43; and other autoimmune diseases, 30, as well as 50 healthy controls (HC). SAA levels were measured using an ELISA assay and western blot analysis was used to detect serum SAA levels. The correlations between SAA levels and disease activity score for 28 joints (DAS28), erythrocyte sedimentation rate (ESR) and C‑reactive protein (CRP), respectively, were evaluated; in addition, the presence and absence of rheumatoid factor (RF) and anti‑cyclic citrullinated peptide antibody (anti‑CCP) were detected in respect to SAA levels. The results of the present study demonstrated that serum levels of SAA in RA patients were significantly increased compared to those of the OA, SLE, others and HC patients (P<0.05). SAA levels were found to be positively correlated with DAS28, ESR and CRP levels (R2=0.6174, 0.4422 and 0.3919, respectively). In addition, anti‑CCP was not correlated with DAS28 (R2=0.0154). Furthermore, increased SAA levels were detected in patients with positive anti‑CCP compared with those in anti‑CCP negative subjects (P<0.01). In conclusion, the results of the present study provided further evidence for possible roles of SAA in RA, which indicated that it may be a useful biomarker for assessing disease severity and may provide additional information about disease activity.
authors.affiliation: Department of Clinical Immunology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, P.R. China.
authors.forename: Chen
authors.initials: C
authors.lastname: Shen
authors.affiliation: Department of Clinical Immunology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, P.R. China.
authors.forename: Xu-Guo
authors.initials: XG
authors.lastname: Sun
authors.affiliation: Department of Clinical Immunology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, P.R. China.
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Medical Laboratory, Tianjin Hospital of Children, Tianjin 300074, P.R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Mu
authors.affiliation: Department of Clinical Immunology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, P.R. China.
authors.forename: Cheng-Cheng
authors.initials: CC
authors.lastname: Hong
authors.affiliation: Department of Rheumatology, General Hospital, Tianjin Medical University, Tianjin 300052, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.affiliation: Department of Clinical Immunology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, P.R. China.
authors.forename: Fang
authors.initials: F
authors.lastname: Zheng
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism*; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000378:metabolism / Q000473:pathology*; D001323:Autoantibodies / Q000097:blood*; D001327:Autoimmune Diseases / Q000378:metabolism / Q000473:pathology; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008180:Lupus Erythematosus, Systemic / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D010003:Osteoarthritis / Q000378:metabolism / Q000473:pathology; D012217:Rheumatoid Factor / Q000378:metabolism; D000685:Serum Amyloid A Protein / Q000032:analysis*; D012720:Severity of Illness Index; D013582:Synovial Fluid / Q000378:metabolism
chemical_list: D000209:Acute-Phase Proteins; D001323:Autoantibodies; D000685:Serum Amyloid A Protein; D002097:C-Reactive Protein; D012217:Rheumatoid Factor