Participation of RANTES and T-cell apoptosis in human renal allograft

Abstract

The aim of this study was to evaluate the serum RANTES (Regulated upon Activation of Normal T cell Expressed and Secreted) levels and the expression of CCR5, as well as the percentage of apoptotic cells, in peripheral T lymphocytes from renal transplanted patients with acute rejection (AR), chronic rejection (CR) or stable evolution (SE). RANTES serum levels were determined by enzyme-linked immunoadsorbent assay and CCR5 expression, as well as the percentage of apoptotic lymphocytes, on a FACScan flow cytometer. After staining with different antibodies, the cells were subjected to three-colour flow cytometric analysis. Data analysis was performed using WINMDI 2.5 software. The serum RANTES level and percentages of CCR5/CD4 and CCR5/CD8 T lymphocytes in CR, AR and SE were lower than that in the control group (P < 0.05). The level of CD4 and CD8 T lymphocytes in early apoptosis was higher in AR patients than in CR, SE or C groups (P < 0.05). In the case of late apoptosis, the percentage of apoptotic/necrotic cells was higher in the CR than AR, SE or C groups (P < 0.05). The RANTES serum levels and the percentage of peripheral CCR5 T lymphocytes would not indicate the renal allograft state. The increase of early apoptotic T lymphocytes could be a marker of AR process and could also indicate the initial step in reducing the cytotoxic T lymphocytes, thus favouring the graft evolution.