Systemic Lupus Erythematosus Of Cd4 ~ + Cd25 To + T-cell Marker Foxp3 Promoter Region Methylation Level

Objective:1.To investigate the expression of foxp3 on CD4+CD25+regulatory T cell in peripheral blood of patients with systemic lupus erythematosis.2.To investigate the methylation status of the FOXP3 promoter in CD4+CD25+regulatory T cell of patients with systemic lupus erythematosis and its role in the pathogenesis of SLE.Method:The patients with systemic lupus erythematosis (30) and healthy controls (20) were recruited, which include 18 new-onset patients with active SLE (SLEDAI>10) and 12 patients with inactive SLE (SLEDAI<3). The expression of foxp3 CD4+CD25+T cell was analyzed by flow cytometry. The magnetic beads assay was used to isolate the CD4+CD25+T cell. The methylation status difference of the FOXP3 promoter in CD4+CD25+regulatory T cell between patients with SLE and healthy controls was detected by bisulfite-sequencing technology.Results:1. It was showed by flow cytometry that the percentage of CD4+CD25+T cell in patients with active, inactive SLE and controls was 4.8%±08,5.1%±0.7,5.3%±1.0, there was no significant difference in the percentage of CD4+CD25+T cell between SLE patients and healthy controls.2. The percentage of CD4+CD25+FOXP3+T cell in patients with active, inactive SLE and controls was 2.9%±0.6,3.5%±0.6,4.1%±0.9.The percentage of CD4+CD25+FOXP3+T cell in SLE patients were significantly lower than those of healthy controls (p<0.05)3.The percentage of CD4+CD25+FOXP3+T cell in SLE patients shows negative correlations with SLEDAI.4. The methylation status of the FOXP3 promoter-77,-65 site in CD4+CD25+regulatory T cells in patients with active SLE and controls was 33.3%,5%。The methylation status of the FOXP3 promoter in CD4+CD25+regulatory T cells in patients with active SLE was more than those of healthy controls. The results are statistically significant. Though the methylation status of the FOXP3 promoter-137,-126,-113,-58,-43,-15 site in CD4+CD25+regulatory T cells of active SLE patients was more than those of healthy controls, the results are not statistically significant.Conclusion:1. Though there was no significant difference in the percentage of CD4+CD25+T cell between SLE patients and healthy controls, the percentage of CD4+CD25+FOXP3+T cell in SLE patients were significantly lower than those of healthy controls.The down-regulation of Foxp3 expression in the peripheral regulatory Tcells may be involved in SLE.2.There was negtive correlation between SLE disease activity and the percentage of CD4+CD25+FOXP3+T cell in SLE patients. 3.The increase of the methylation status of the FOXP3 promoter-77,-65 site in CD4+CD25+ regulatory T cells in patients may be involved in SLE. The effective interventions for the treatment of SLE can be designed to follow the mechanism, it is a new way of thinking.