This is a review of the University of Alabama Hospital's clinical experience with 1-haplotype-mismatched LRD renal transplants, utilizing a stored-blood DST protocol and with cadaveric renal transplants utilizing DBM transfusion. Stored-blood DST does not significantly improve LRD allograft survival either in Aza-, P-, or CsA-treated patients, although there is a trend toward better survival in Aza/DST versus Aza/no-DST recipients (78% vs 84% 12-month allograft function). Importantly, although the early acute phase graft loss was slightly diminished by DST, the late phase loss (slope of curve) was essentially identical to nontransfused patients. Thus, we cannot demonstrate a beneficial effect by the use of DST in achieving improved long-term graft survival in recipients of 1-haplotype-matched recipients. The use of cryopreserved DBM transfusions in cadaveric allograft recipients, however, has resulted in significantly improved survival compared to control patients who received the marrow donor's contralateral kidney and similar immunosuppression without marrow infusion [92% vs 73% (p = 0.01)]. DBM-transfused patients demonstrate diminished donor-specific responsiveness in MLC compared with controls. P withdrawal can be accomplished safely in the majority of marrow recipients; however, this has not been tested in the controls. Donor-nucleated cells persist in the peripheral blood of some DBM-transfused patients for at least 2 years following transplantation. Presently, the significance of persistent chimerism in these patients with respect to donor responsiveness and allograft tolerance is unclear.