Serum Levels And Significances Of Toll-like Receptor7in Rheumatoid Arthritis

Objective: To analyze the serum levels of Toll-like receptor7(TLR7) in Collagen-Induced Arthritis(CIA), and to investigate the role of serum TLR7in pathogenesis ofrheumatoid arthritis (RA).Methods: Thirty DBA/1mice were randomly divided into three groups: normalcontrol group, model group and treatment group. CIA were established by immunizingmice with cow TypeⅡCollgen and complete Freunds adjuvant. Arthritis Index(AI) wererecorded after one week.And the levels of TLR7and VEGF in serums are detected byEnzyme-Linked ImmunoSorbent Assay(ELISA). At the same time, their joints werecollected to be made into sections to be inspected for pathology purpose with amicroscope.Results:①The concentrations of TLR7in normal control group, model group andtreatment group were:1.23±0.09,1.10±0.05,1.19±0.12ng/ml. It was obviously lower inmodel group when compared to the other two groups. Significant differences were shownbetween model group and normal control group (P<0.01), model group and treatmentgroup (P<0.05), but no significant difference between treatment group and normal controlgroup (P>0.05).②The concentrations of VEGF in normal control group, model group andtreatment group were:13.93±2.86,17.93±2.42,14.97±1.98ng/1. It was obviously higher inmodel group when compared to the other two groups. Significant differences were shownbetween model group and normal control group (P<0.01), model group and treatmentgroup (P<0.01), but no significant difference between treatment group and normal controlgroup (P>0.05).③The outcomes of arthritis index were:0.00±0.00,6.40±1.84,3.50±1.51.Significant differences were shown between model group and normal control group (P<0.01), and so did model group and treatment group (P<0.01).④The outcomes of jointpathology score were:0.00±0.00,5.00±1.05,2.70±0.82. Significant differences wereshown between model group and normal control group (P<0.01), and so did model groupand treatment group (P<0.01).⑤The outcomes of synovial tissue pathology score were:0.00±0.00,7.00±1.76,3.90±1.73. Significant differences were shown between modelgroup and normal control group (P<0.01), and so did model group and treatment group(P<0.01).⑥Negative correlations were found between TLR7and those indexes (arthritisindex, joint and synovial tissue pathology score)by correlation analysis, and so did VEGF;Positive correlations were found between VEGF and those indexes.Conclusion: The expression of TLR7in model group is significantly lower thannormal control group and treatment group, which indicates that serum TLR7may beinvolved in the pathogenesis of RA by suppressing or deplaying the process of synovialhyperplasia, pannus formation, cytokine secretion and cartilage erosion as well as bonedestruction. Serum TLR7is expected to become a potential target for diagnosis andtreatment of RA.