The risk of severe graft versus host disease (GVHD) is increased with the use of unrelated and partially matched related donors. T cell depletion reduces the risk of severe GVHD, but immune reconstitution is delayed. Important memory T cells that may protect patients from fungal and viral infections are also removed in the T depletion process. CD45RA depletion has been studied both as a single step to reduce the risk of GVHD, and also, in conjunction with αβTCR depleted hematopoietic stem cell grafts to accelerate immune reconstitution. This is a single institutional pilot trial of this T cell depletion technique. Patients with acute leukemias at high risk for relapse are eligible to participate. Patients will be given CD45RA depleted donor peripheral stem cells (PSCs) following T depleted hematopoietic stem cell transplant (HSCT). A short course of GVHD prophylaxis will be used after CD45RA depletion.
