Ex vivo expansion of haematopoietic stem cells to improve engraftment in stem cell transplantation.

The efficient use of haematopoietic stem cells (HSC) for transplantation is often limited by the relatively low numbers of HSC collected. The ex vivo expansion of HSC for clinical use is a potentially valuable and safe approach to increase HSC numbers thereby increasing engraftment and reducing the risk of morbidity from infection. Here we describe a protocol for the robust ex vivo expansion of human CD34(+) HSC isolated from umbilical cord blood. The protocol described can efficiently generate large numbers of HSC. We also describe a flow cytometry-based method using high resolution division tracking to characterise the kinetics of HSC growth and differentiation. Utilising the guidelines discussed, it is possible for investigators to use this protocol as presented or to modify it for their specific needs.