Involvement of indirectly allostimulated CD4+CD43highCD45RO+ T cell proliferation in the development of chronic allograft nephropathy.

The goal of this study was to identify immunological markers for use in antigen-specific assays that predict long-term survival after renal allograft and distinguish stable-functioning (SP) patients from poorly functioning (PP) patients. For this prospective study, 20 patients were enrolled. Eight SP and six PP patients were enrolled in this study. Serum cytokine/chemokine levels were analyzed by the Luminex multiplex assay. To detect indirect alloreactive T cells, we performed indirect mixed lymphocyte reaction using donor-antigen-pulsed autologous dendritic cells as stimulators. Serum induced protein-10 levels were significantly higher in the serum of PP patients, whereas sCD40L levels were higher in SP patients. The PP patients had significantly higher numbers of donor-specific CD4(+)CD43(high)CD45RO(+) T cells after indirect allostimulation, whereas this cell population was unchanged in SP patients. The donor-specific CD4(+)CD43(high)CD45RO(+) T cells had the effector memory T cell phenotype. Prospectively, we studied whether these cells influence graft outcome and found that their strong proliferation in pre-transplant patients is related to a poorly functioning graft. Indirectly allostimulated CD4(+)CD43(high)CD45RO(+) T cells may not only contribute to chronic allograft nephropathy development but may also have a role in the progression of acute rejection. Thus, these cells may have potential use as immune-monitoring markers in a noninvasive in vitro assay that predicts graft outcome.