Experimental basis of cord blood transplantation

Efforts are needed to enhance the efficacy of cord blood (CB) transplantation. Laboratory information set the stage for the first and subsequent CB transplants, and will be instrumental in continuing to advance the field. This paper offers a brief understanding of the current state of hematopoietic stem cell (HSC) and hematopoietic progenitor cell (HPC) biology, a look back at laboratory studies leading to the first CB transplants, and a discussion of the possible means to enhance CB transplantation. Results show that physical recovery of greater numbers of HPCs is possible after CB is collected by perfusing the placenta, but how realistic this procedure is for collection of CB to be banked is open to question. We also show that the chemokine stromal cell-derived factor-1/CXCL12 can enhance the ex vivo expansion of CB HPCs beyond that of the combination of SCF, Flt3-ligand and TPO. Advances in cytokine and stromal cell biology, and in intracellular signals mediating the effects of cytokines/stromal cells should be considered in the context of future efforts to enhance functional activities of donor CB HSCs and HPCs and the microenvironmental niche of the recipient, which is required for acceptance and nurturing these HSCs/HPCs.