[Changes of peripheral blood CD4(+)CD25(+) regulatory T cells and TREG-related Foxp3 gene expression at the onset of chronic allograft nephropathy].

OBJECTIVE

To investigate the changes of CD4(+)CD25(+) regulatory T cells (TREG) and TREG-related foxp3 gene expression in the peripheral blood at the onset of chronic allograft nephropathy (CAN) after kidney transplantation.

METHODS

Twenty-five patients with initial onset of CAN were examined for CD4(+)CD25(+)high/CD4(+) ratio and the expression of Foxp3 gene in the peripheral blood using the flow cytometry, and the data were compared with those of 30 kidney recipients with normal graft function, 20 patients with chronic renal function (CRF), and 20 normal subjects. All the recipients had no more than 1 HLA mismatch and received the same inductive and maintenance drug treatment.

RESULTS

The recipients with CAN had significantly lower CD4(+)CD25(+)high/CD4(+) ratio and Foxp3 gene expression compared with those with normal graft function (0.71∓0.33 vs 1.17∓0.25 and 62.75∓10.80 vs 70.42∓6.8, respectively, P<0.01). The recipients with normal renal graft function showed no significant difference in CD4(+)CD25(+)high/CD4(+) ratio and Foxp3 gene expression from the normal control subjects.

CONCLUSION

The peripheral blood CD4(+)CD25(+)high/CD4(+) ratio and Foxp3 expression in the kidney recipients with CAN are significantly lower than those of recipients with normal renal graft function, which does not correlate with elevated creatinine level, suggesting a role of TREG in the occurrence and development of CAN.