New insights into cord blood stem cell transplantation.

PURPOSE OF REVIEW To review the available clinical and biological advances of umbilical cord blood allogeneic stem cell transplantation in pediatric and adult patients. RECENT FINDINGS Recent large international studies suggested that allogeneic umbilical cord blood transplantation may potentially emerge as the frontline stem cell source for pediatric patients with hematopoietic malignancies because of its ability to confer superior overall and relapse-free survival compared with matched marrow stem cells. In adults, umbilical cord blood transplantation, double umbilical cord blood units and nonmyeloablative engraftment strategies have attracted further attention in clinical practice with the advantages of possible stronger graft-versus-leukemia effect and expanding transplantation indications. Additional advances in the basic biology of umbilical cord blood also appear very promising in development of enhanced engraftment approaches for limiting hematopoietic stem cell numbers or expansion of repopulating cells. SUMMARY Umbilical cord blood is a valuable alternative source of hematopoietic stem cells for patients that require allogeneic transplantation in the absence of readily available human leukocyte antigen matched marrow or blood hematopoietic stem cells. The current advances in clinical and biological research will further expand its application in pediatric and adult hematopoietic stem cells transplantation for treating hematologic disorders.