Correlation Between Serum MBL And MASP-2 Levels In Rheumatoid Arthritis

Rheumatoid arthritis(rheumatoid arthritis,RA) is a chronic autoimmune disease characterized by joint swelling, stiffness, pain, and progressive bone destruction. So far, its pathogenesis has not been fully confirmed until now. The complement system is a highly complex and biological response system which is the first immune defense to resist the invasion of pathogens.There are three complement activation pathways in human’s body: the classical pathway, the bypass pathway, and the mannose binding lectin pathway(mannan-binding lectin, MBL). The MBL pathway complement activation is different from the classical and alternative one. The acting MBL pathway makes the complements active in order through binding the MBL associated serine protease(mannan binding lectin associated serine proteases, MASP) without any antibodies. And the MASP-2 is the key enzyme in the MBL pathway. In recent years, more and more studies have found that the MBL pathway plays an important role in many diseases.And its research field has been widely concerned by scholars.Objective:The aims of this study were to explore the level and activity of MBL pathway elements(MBL,MASP-2, C4 and C3) in RA, and to explore the effective assessment of diagnosis and changing pathology of RA.Methord: Searches covered the period from December 2014 to October 2015,90 serum samples in Second Hospital of Lanzhou University, including 50 cases of RA patients serum samples(25 cases of active, 25 non active) and 40 cases of healthy control group, and were conducted using immune turbidity assay to detect the serum complement C3 and C4 and high sensitive C reactive protein(Hs CRP) levels; and using enzyme-linked immunosorbent assay(ELISA) to detect the serum MBL and MASP-2 level;and by doing the C4 b deposition to detect serum MASP-2 activity.Result: Erythrocyte sedimentation rate in RA patients was(50.44±34.28)mm/h and anti-cyclic citrullinated peptide antibody was(105.53±93.21) RU/Ml which were higher than those in the healthy control group [(9.08±7.74) mm/h,(12.56±4.52) RU/m L] with significant difference(P < 0.05).The level of MBL in serum of active and non-active RA group were significantly lower than that in the healthy control group(ng/m L:10.05±2.14 vs 26.97±11.78; 14.79±3.93 vs 26.97±11.78(P < 0.05); The level of MASP-2 in serum of RA group of active and non-active were significantly lower than the healthy control group(ng/m L:75.90±9.21 vs 251.78±34.50; 107.8± 14.90 vs 251.78±34.50)(P < 0.05); serum MASP-2 activity in active and non-active RA group were significantly lower than the healthy control group(1/X: 72 vs 614; 262 vs 614)(P < 0.05); The level of C4 in serum of activity RA group significantly higher than that the healthy control group(g/L:0.30±0.13 vs. 0.23±0.07)(P < 0.05); While there is no difference between non active RA group(g/L:0.27±0.06) and the healthy control group(P> 0.05); The level of Hs CRP in serum of active and non-active RA group was significantly higher than that in the healthy control group(mg/L:40.53±34.81 vs 1.42±1.70; 2.97±2.51 vs 1.42±1.70)(P< 0.05); but no difference were observed in the C3 level among three groups.Based on Bivariate Pearson correlation analysis, the content and activity of MBL and MASP-2 in RA patients showed a significant positive correlation(r=0.550, P=0.001; r=0.575, P=0.001);and the content of C3 and C4 had no correlation(r=-0.022, P=0.882; r=-0.295, P=0.037); And the content of Hs CRP showed weak negative correlation in RA patients(r=-0.323, P=0.022).The content and activity of MASP-2 in RA patients was significantly positive correlation(r=0.608, P=0.001); While the C3 content has no correlation(r=-0.049, P=0.738); and C4, Hs CRP content is also weak negative correlation(r=-0.399, P=0.004; r-0.453, P=0.001).Conclusion: Compared with healthy control group, the levels of serum C4 and Hs CRP in active and non-active RA patients were both elevated, and the levels of MBL and MASP-2 were decreased, which suggested that the lectin pathway of MBL and MASP2 activation was involved in the progress of RA.the levels and activity of MBL and MASP-2 were much lower which means that with a progressing injury of joints in RA patients. the content of MBL/MASP-2 as the basis of predicting disease progression.With respect to the Correlation analysis, C3 and C4 were not founded to be associated with serum MBL, but MBL and MASP-2 levels were positively correlated in patients with RA; The levels and activity of MASP-2 had a positive correlation, C3 was not founded to be associated with serum MASP-2.detecting serum MBL/MASP-2 levels has a certain reference value auxiliary diagnosis of RA..