COLLECTION, SEPARATION AND CRYOPRESERVATION OF UMBILICAL-CORD BLOOD FOR USE IN TRANSPLANTATION

Bone marrow transplantation (BMT) is limited by the paucity of HLA-mat ched donors and the frequent occurrence of graft-versus-host disease ( GVHD). Recent clinical reports have implied that the use of umbilical cord blood (UCB) may alleviate some of the problems associated with BM T. Banks of frozen UCB could make the problem of finding suitable stem cell donors easier and stem cell grafts would be more readily availab le. However, definitive experiments are needed to develop optimal meth ods for collection, separation and storage of cryopreserved UCB for ex tended periods of time. We have found that several simple techniques m ay be utilized to collect large volumes of UCB (up to 220 ml). Also, m odification of a common density gradient separation method permits rec overy of large quantities of UCB mononuclear cells. Finally, we have e xamined the effects of prolonged frozen storage on the ability to reco ver viable and functional UCB, particularly stem/progenitor cells. It was observed that storage of UCB in liquid nitrogen for as long as 7 y ears had minimal effects on cell viability, cellular composition of UC B and progenitor/stem cell capacity. Thus, the establishment of UCB ba nks for use in transplantation appears to be a feasible approach.