Soluble CD30 as a predictor of kidney graft outcome.

BACKGROUND: In the present study, we investigated whether the soluble form of CD30 (sCD30), a marker for T helper 2-type cytokine-producing T cells, is increased in sera of potential kidney graft recipients. We also investigated whether the pretransplantation serum sCD30 content is related to kidney graft survival. METHODS: Pretransplantation sera of 844 cadaver kidney recipients from three transplant centers in Germany were tested for serum sCD30 content using a commercially available ELISA kit. RESULTS: Kidney graft recipients showed a significantly higher serum sCD30 content than healthy controls (P<0.0001). High sCD30 serum content was associated with graft rejection. The 2-year graft survival rate in recipients with a high pretransplantation serum sCD30 was 68+/-6%, significantly lower than the 86+/-1% rate in recipients with a low sCD30 (P<0.0001). Importantly, high sCD30 was indicative of an increased risk of graft loss even in recipients without lymphocytotoxic alloantibodies. CONCLUSION: These data show that an elevated pretransplantation serum sCD30 reflects an immune state that is detrimental for kidney graft survival.