Expression Analysis Of The Levels Of S100A8/A9 And S100P In Synovial Membrane And Serum Of Patients With Rheumatoid Arthrtis

Objective: Comparing S100A8/A9 and S100 P expression in the synovial tissues and serum of patients with rheumatoid arthritis(RA),osteoarthritis(OA)and healthy controls(HCS).this study was to assess the diagnostic value of S100A8/A9 and S100 P for RA.The associations between S100A8/A9 and S100 P levels and the clinical and laboratory parameters in RA patients was also analyzed at the same time.Methods: S100A8/A9 protein and S100 P protein expression was detected in synovial tissue from patients with RA(n=5),patients with OA(n=5)and HCS(n=4)by Western blot(Wb).Serum S100A8/A9 and S100 P levels were measured by ELISA in patients with RA(n=60),patients with OA(n=48)and HCS(n=35).Disease activity scores in 28 joints based on C-reactive protein(DAS28-CRP)were used to assess disease activity.The ESR was measured using the Westergren method,and CRP measured by use of turbidimetry,Levels of serum anticyclic citrullinated peptide antibodies(anti-CCP)and rheumatoid factor immunoglobulin M(RF-IgM)were detected using standard ELISA kits.Results: 1.we confirmed by immunoblotting that S100A8 /A9 and S100 P were increased in RA in synovial tissue in comparison with OA or HCS.2.Serum S100A8/A9 concentrations were significantly increased in patients with RA(77.7(16.2-174.4)ng/ml)compared to OA(28.6(11.9-42.9)ng/ml)and HCs(8.9(7.2-10.1)ng/ml).All the differences were statistically significant(p <0.01).Receiver operating characteristic(ROC)analysis demonstrated that S100A8/A9 could distinguish RA patients from OA patients and HCs(AUC= 0.82).The cut-off value of S100A8/A9 was defined as 46.08 ng/ml,and its sensitivity and specificity for RA diagnosis were 63.3% and 90.4%,respectively.The positive rate of S100A8/A9 was significantly higher in RA(38/60,63.3%)compared to OA(8/48,16.7%)and HCs(0/35,0%).The differences were statistically significant(p < 0.01).At the same time,serum S100A8/A9 levels were positively correlated with 28 swollen joint counts,28 pain joint counts,DAS28 scores,rheumatoid factor IgM(RF-IgM),and erythrocyte sedimentation rate(ESR)in patients with RA.There was no correlation between citrullinated peptide antibody(anti-CCP)levels,ESR,disease duration,and age with serum S100A8/A9.In multiple linear regression analysis with DAS28 as a dependent variable,S100A8/A9 had a greater effect on DAS28 score than CRP and ESR.3.Serum S100 P concentrations were significantly increased in patients with RA(57.3(52.9-63.5)ng/ml)compared to OA(45.1(36.6-57.8)ng/ml)and HCs(40.9(35.3-50.5)ng/ml).All the differences were statistically significant(p<0.001).Receiver operating characteristic(ROC)analysis demonstrated that S100 P could distinguish RA patients from OA patients and HCs(AUC=0.796).The cut-off value of S100 P was defined as 50.7ng/ml,and its sensitivity and specificity for RA diagnosis were 85.0% and 68.7%,respectively.The positive rate of S100 P was significantly higher in RA(51/60,85.0 %)compared to OA(18/48,37.5 %)and HCs(8/35,22.9 %)(P<0.001).Serum S100 P were positively correlated with serum RF-IgM levels and anti-CCP levels.Conclusion: 1.Our results indicate that S100A8/A9 protein and S100 P protein are significantly elevated in synovial tissue of RA patients.Possible implication of S100A8/A9 protein and S100 P protein in this increase may play a role in RA physiopathology.2..Serum levels of S100A8/A9 are significantly elevated in RA patients and may have the potential for RA diagnose and monitor disease activity biomarker.3.Serum levels of S100 P are significantly elevated in RA patients and S100 P may have potential for RA diagnosis.