ABSTRACT

I. INTRODUCTION The biological effects of allogeneic hematopoietic transplantation depend on the cellular composition of the graft. Hematopoietic stem and progenitor cells for transplantation can be obtained from bone marrow, mobilized peripheral blood, or cord blood. The goal for patients transplanted for malignancies is to achieve engraftment, develop the immunemediated graft-versus-malignancy effect, whereas avoiding graft-versus-host disease (GVHD). This is a major challenge, since T cells participate in each of these processes and altering the composition of the graft may produce both positive and negative effects. Innovative technology is under evaluation to reduce the alloreactivity of the graft and for the later infusion of immunocompetent cells to enhance immunoreconstitution and graftversus-leukemia (GVL).