My career has been focused on the development of alternative hematopoietic stem cell donor sources, and novel cellular therapy strategies to extend the use and improve the safety and efficacy of hematopoietic cell transplantation (HCT). I have led prospective and retrospective studies on the outcomes of cord blood transplantation, and its relative efficacy as compared to other allogeneic donor types, at the institutional and national level. I have also led studies on the impact human leukocyte antigen (HLA) matching on HCT outcomes. Specifically, I studied how the level of HLA-matching, the number of HLA-loci considered, donor-donor HLA-matching in double cord blood HCT, and killer immunoglobulin receptor ligand mismatching influenced the outcomes of cord blood transplantation. I have also be involved on the use of cellular therapy and the modulation immunological factor in order to reduce complications and improve efficacy of HCT. These studies involved the adoptive transfer of regulatory T-cells to reduce risk of graft-vs.-host disease, cord blood unit manipulation (e.g. C3a priming) and ex-vivo expansion to accelerate engraftment, and the adoptive transfer and stimulation of NK-cells with interleukin-15 and analogs to treat and prevent myeloid malignancy relapse.