Biol Blood Marrow Transplant. 2014 Dec 30. pii: S1083-8791(14)01466-9. doi: 10.1016/j.bbmt.2014.12.022. [Epub ahead of print]

Expansion and Homing of Umbilical Cord Blood Hematopoietic Stem and Progenitor Cells for Clinical Transplantation.

Bari S¹, Hong Seah KK², Poon Z³, Sze Cheung AM⁴, Fan X⁵, Ong S⁶, Li S⁴, Koh LP⁷, Khee Hwang WY⁸.

Abstract

The successful expansion of hematopoietic stem and progenitor cells (HSPCs) from umbilical cord blood (UCB) for transplantation could revolutionize clinical practice by improving transplant-related outcomes and making available UCB units that have suboptimal cell doses for transplantation. New cytokine combinations appear to be able to promote HSPC growth with minimal differentiation into mature precursors and new agents like IGFBP2 are being used in clinical trials. Molecules that simulate the HSPC niche like Notch-ligand have also shown promise. Further improvements have been made with the use of mesenchymal stromal cells (MSCs), which have made possible UCB expansion without a potentially deleterious prior CD34 / CD133 cell selection step. Chemical molecules like copper chelators, nicotinamide and aryl hydrocarbon antagonists have shown excellent outcomes in clinical studies. The use of bioreactors could further add to HSPC studies in future. Drugs which could improve HSPC homing also appear to have potential in improving engraftment times in UCB transplant. Technologies to expand HSPC from UCB and to enhance the homing of these cells appear to have attained the goal of accelerating hematopoietic recovery. Further discoveries and clinical studies are likely to make the goal of true HSPC expansion a reality for many applications in future.