The Role Of Molecular Chaperone HSP90 And IL-6, IL-18 In The Pathogenesis Of Systemic Lupus Erythematosus

PartⅠ: Expression of HSP90 in the systemic lupus erythematosus Objective:To investigate the expression of heat shock protein 90 (HSP90) in peripheral blood mononuclear cells (PBMC). And to explore its possible role in the pathogenesis of SLE.Methods:There have 20 normal control subjects (group I), and according to Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), the SLE patients were classified into two groups: group II (5≤SLEDAI<10, n=14) and groupⅢ(SLEDAI≥10, n=25). Western blot technique was used to analyze HSP90 expression in peripheral blood mononuclear cells (PBMC) from 39 SLE patients and 20 normal controls.Results:The mean level of HSP90 expression in group I,group II and groupⅢwere 0.37±0.11, 0.54±0.09, 0.82±0.10, respectively. The statistic differences among the three groups were significant (both p<0.01). There has correlation between HSP90 and SLEDAI (r= 0.60, p<0.01).Conclusion:Hsp90 as a molecular chaperone, may participate in mediating the autoimmune function, and have important role in the pathogenesis of SLE. And the level of HSP90 correlate with the SLEDAI, so the level of HSP90 might be used as a referential indicators. PartⅡ: Expression of IL-6, IL-18 in systemic lupus erythematosus Objective:To investigate the serum level of IL-6 and IL-18, And to explore the correlation of SLEDAI and HSP90.Methods:There have 20 normal control subjects (group I), and according to Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), the SLE patients were classified into two groups: group II (5≤SLEDAI<10, n=14) and groupⅢ(SLEDAI≥10, n=25). ELISA was applied to determine the serum level of IL-6 and IL-18 from 39 SLE patients and 20 normal controlsResults:1. The mean serum levels of IL-6 in-group I group II and groupⅢwere 10.46±4.33pg/ml, 28.99±1.74pg/ml, 44.58±9.15pg/ml, respectively. The statistic differences among the three groups were significant (both p<0.01).2. The mean serum levels of IL-18 in group I, group II and groupⅢwere 252.32±76.45pg/ml, 327.82±101.45pg/ml, 459.79±134.08pg/ml, respectively. The statistic differences between the three groups were significant (group I vs. group II P<0.05, group I vs. groupⅢ, group II vs. groupⅢ, both p<0.01).3. The level of IL-6 and SLEDAI, IL-18 and SLEDAI, were positive correlation in SLE group (r = 0.73,p< 0.01, r = 0.49, p< 0.01, respectively). But there was no correlation between the level of IL-6 and IL-18 (r=0.41, p >0.05).4. There was a positive correlation between the level of IL-6 and HSP90 in SLE group (r=0.61, p<0.01), but there was no correlation between the level of IL-18 and HSP90 in SLE group (r=0.36,p >0.05).Conclusion:The serum level of IL-6, IL-18 was elevated, IL-6 may induce the expression of HSP90, and play an important role in the pathogenesis and development of SLE.