The Study On The Expression Of Serum IL-28B And Its Association With Clinical Features In Rheumatoid Arthritis

Objectives: Rheumatoid arthritis(RA)is a chronic and progressing inflammatory disease characterized by symmetrical inflammation of the synovial membrane and bone erosion.Interleukin-28B(IL-28B)is a member of the interferon lambda family(also known as type III interferons),it has already been studied in many diseases.However,there is no report about IL-28 B in patients with rheumatoid arthritis.IL-29 is another number of type III interferons,which has 81% homology to IL-28 B.It was over expressed in blood and synovium of RA patients and triggered proinflammatory cytokine interleukin-6(IL-6)and interleukin-8(IL-8)m RNA expression in RA synovial fibroblasts(RA-FLS),which may ultimately contribute to synovial inflammation.Therefore,we determined the serum levels of IL-28 B in RA patients before disease-modifying anti-rheumatic drugs(DMARDs)therapy and 1 month,3 months and 6 months after DMARDs and determined the correlation of serum IL-28 B levels with clinical features,laboratory values and radiographic score in RA patients to find out the possible link of IL-28 B to RA.Methods: This study involved 80 RA patients fulfilling 1987 American College of Rheumatology(ACR)classification criteria or ACR /European League Against Rheumatism(EULAR)2010 classification criteria.And 80 healthy persons with no difference in age and sex were selected as control group.IL-28 B levels were measured by enzyme-linked immunosorbent assay(ELISA)in 80 RA patients before DMARDs therapy and 1 month,3 months and 6 months after DMARDs and 80 healthy controls.Radiographs were scored for total Sharp score(TSS).Collect patient clinical data,including age,sex,disease duration,morning stiffness,resting pain in joints,Health assessment questionnaire(HAQ),physician assessment of pain,patient assessment of pain,joint function grading,tender joints,swollen joints,erythrocyte sedimentation rate(ESR),C reactive protein(CRP),platelet,rheumatoid factor(RF),anti-cyclic citrullinated peptide(CCP)antibody,immunoglobulin-A(Ig-A),immunoglobulin-G(Ig-G),Immunoglobulin-M(Ig-M)and calculate disease activity score-28 base on ESR(DAS28-ESR),disease activity score-28 base on CRP(DAS28-CRP).Results: Serum IL-28 B levels were significantly lower in the RA than in the control(p=0.020).Anti-CCP antibody and RF were negatively correlated with serum IL-28 B levels(p=0.010,p=0.042).Serum IL-28 B levels in anti-CCP antibody-positive patients were lower than in anti-CCP antibody-negative patients and healthy controls(p=0.047,p=0.007).But no difference was observed in serum IL-28 B levels between anti-CCP antibody-negative patients and healthy controls.Serum IL-28 B levels in RF-positive patients were lower than in RF-negative patients and healthy controls(p=0.010,p=0.002).But no difference was observed in serum IL-28 B levels between RF-negative patients and healthy controls.There was no association between serum IL-28 B levels and TSS before and after DMARDs therapy,but there was a significant difference in change of IL-28 B during 6 months follow up between progressors and non-progressors(p=0.028).The disease activity of RA patients decreased,but no difference was observed in serum IL-28 B levels between before and after DMARDs therapy.Conclusions: These findings indicated a role of IL-28 B in RA.It may contribute to avoiding osteoclasia in RA patients and develop to be a new treatment in alleviating bone destruction.And serum IL-28 B levels did not change with disease activity.DMARDs were effective in reducing the inflammation of RA,but can’t affect the secretion or metabolism of IL-28 B.