Umbilical Cord Blood Hematopoietic Stem Cell Transplantation, an Alternative to Bone Marrow

Umbilical cord blood (UCB) is an alternative hematopoietic stem cell (HSC) source. It is widely applicable for ameliorating several diseases through HSC transplants. One of the few disadvantages of this source of stem cells is the limited amount of HSCs that can be extracted from each cord blood unit (CBU).Single CBU transplantation seems to be more ideal in lower weight, younger patients. Adult clinical studies comparing HSCs from a single CBU and HSCs from bone marrow indicate that umbilical cord blood transplantation is a viable method when a matched bone marrow transplant cannot be identified. Further clinical studies using two CBUs suggest better engraftment and lower risk of relapse. However, double cord blood transplantation has been faced with the challenge of single unit dominance in most studies. Ex vivo expansion of UCB HSC is another promising method to overcome limited HSC counts.