[摘要]：Background. The novel, recently described allo (antigen)-specific CD154+ T cells were evaluated for their association with acute cellular rejection (ACR) in 43 adult renal transplant recipients receiving steroid-free tacrolimus after alemtuzumab induction. Methods. Single blood samples corresponding to "for cause" allograft biopsies were assayed for CD154+ naive or memory T-helper or T-cytotoxic cells in 16-hr mixed leukocyte reaction. Results. Intra-and interassay variation was less than 10% for a variety of conditions. In logistic regression, leave-one-out cross-validation, and receiver-operating characteristic analyses, the rejection-risk threshold of allospecific CD154+ T-cytotoxic memory cells (TcMs) associated best with biopsy-proven ACR with a sensitivity/specificity of 88% in 32 of 43 subjects. Sensitivity/specificity of 100%/88% was replicated in blinded prediction in the remaining 11 subjects. Allospecific CD154+ TcM correlated inversely with CTLA4+ TcM (Spearman r= -0.358, P=0.029) and increased significantly with increasing histological severity of ACR (P=2.99E-05, Kruskall-Wallis). Conclusions. The strong association between ACR and allospecific CD154+ TcM may be useful in minimizing protocol biopsies among recipients at reduced rejection risk.
