Effects of TLR/STAT pathway on the proliferation of mesangial cell induced by HMGB1 / 中国免疫学杂志

ABSTRACT

Objective:To investigate the effects of TLR/STAT pathway in the proliferation of mesangial cell induced by HMGB1.Methods:Human mesangial cells were inoculated in the dose of 1?104 ml-1.After 24 h,cells were cultured with standard medium as control group or with medium supplement with 10 ?g/L human recombinant protein HMGB1 as trial group in vitro.Then the cells were collected in 6,12 and 24 h respectively,as well as control group cells.Immunocytochemical staining was adopted to examine the expressions of PCNA proteins on mesangial cells in different groups.Immunocytochemical staining and FCM were performed to detect the changes of TLR2 protein expression.STAT1 and STAT3 mRNA were examined by RT-PCR technique.Results:Immunocytochemical staining indicated that the mesangial cells could multiply after they were induced by human recombinant protein HMGB1.Immunocytochemical staining showed that the level of TLR2 protein in trial groups were higher than those in control groups.FCM indicated that HMGB1 could significantly up-regulate the expression of TLR2 protein time-dependently.The STAT1 and STAT3 mRNA in HMGB1 groups were higher than those in control groups.The expression of TLR2 protein was positively correlated with those of STAT1 and STAT mRNA respectively.The positive rate of PCNA was remarkably correlated with the expression of STAT1 and STAT3 mRNA.Conclusion:HMGB1 could activate STAT1/STAT3 through combining with its cell-surface receptor TLR2,which may play an important role in promoting the proliferation of mesangial cells and then damaging the renal of lupus nephritis.