Ex vivo expansion and engraftment potential of cord blood-derived CD34+ cells in NOD/SCID mice.

For more than 10 years umbilical cord blood (UCB) has been used as an alternative source of hematopoietic stem cells for allogeneic transplantation. Although the clinical results are encouraging, UCB is associated with delayed engraftment. To address these issues we have used the NOD/SCID mouse model to study the engraftment potential of cord blood cells in more detail, to assess the engraftment potential of expanded megakaryocytic progenitor cells, and to study the effect of co-transplantation of mesenchymal stem cells on engraftment.