Study On The Expression And Mechanism Of HMGB1 And TLR2/TLR4 In Rheumatoid Arthritis

Objective To explore the expressions of HMGB1 and TLR2,TLR4 in the patients with rheumatoid arthritis; and study the role of HMGB1/TLR pathway in the pathogenesis of rheumatoid arthritis.Methods1. According to the American College of Rheumatology(ACR)1987 in RA: to select 29 active RA, 20 inactive RA and 18 healthy controls.2. HMGB1 mRNA was detected by reverse transcription chain reaction(RT-PCR) in PBMC in the patients of RA and healthy controls;3. The expression of HMGB1 in serum of these cases were detected by ELISA;4. The expression of TLR2 and TLR4 on CD14+ monocytes in peripheral blood were detected by FCM;5. All subjects were measured ESR,CRP,RF and other clinical relevant indexes. To analyze the correlation between HMGB1 in serum and TLR2,TLR4 on CD14+ monocytes, ESR,CRP,RF,the number of swollen and tender ioints and radiographic.Results1. The HMGB1 mRNA in active RA was significantly higher than inactive group and healthy controls(P<0.05); but it was no difference between inactive group and healthy controls.2. The level of HMGB1 in serum in active RA was significantly higher than inactive group and healthy controls(P<0.05); but it was no difference between inactive group and healthy controls.3. The expression rate and relative protein quantification of TLR2 on CD14+ monocytes in active RA was significantly higher than inactive group and healthy controls(P<0.05); but it was no difference between inactive group and healthy controls.4. The expression of and relative protein quantification of TLR4 CD14+ monocytes in active RA was significantly higher than inactive group and healthy controls(P<0.05); also it is higher in inactive group than in healthy controls(P<0.05).5. The level of HMGB1 in serum in active RA was positively correlated with the relative protein quantification of TLR2 and TLR4(r=0.759,r=0.646. P<0.05),was positively correlated with ESR, CRP and RF(P<0.05). It was not correlated with the number of swollen joints and tender ioints and radiographic. Conclusion The level of HMGB1 in serum can be used as an indicator of RA disease activity.The expression of HMGB1 and TLR2/TLR4 in RA was increased and they were associated with the occurrence and development of RA. HMGB1/TLR pathway may be an important inflammatory start factor in the pathogenesis of RA.