CORD-BLOOD BANKING - UNRELATED TRANSPLANT S

Hematopoietic progenitor cells are present in umbilical cord blood; pl acental blood (PB) previously considered as waste product now constitu tes an alternative source of hematopoietic stem cells for bone marrow reconstitution. This has promoted the establishment of cord blood bank s for use in unrelated transplants. The banking of PB offers many adva ntages: the donors do not require anesthesia, stored PB can be a valua ble source of stem cells for patients from ethnic minorities underrepr esented in volunteer registers, and stored PB can be made available mu ch faster than bone marrow from unrelated donors. Preliminary clinical experience suggests that, due to the immunological immaturity of PF, cells, graft versus host disease might be lower than when using bone m arrow from adult donors and HLA restrictions might be less stringent. if the number of nucleated cells in PB often appears low for patients weighing more than 40 kg, clinical data suggest that the number of ste m cells may be sufficient for adult transplantation. The number of cor d blood banks throughout the world is increasing rapidly. In the USA a nd Europe, more than 10,500 PB units are stored and available for tran splantation. In the next 5 years, a total of 50,000 PB will be reached which may be sufficient to provide for the majority of candidates for unrelated BM transplantation. The practices of umbilical cord blood c ollection, mother selection, infectious disease screening, cell manipu lation and storage must be standardized. Some accreditation process sh ould be mandatory for assessing operating procedures and the quality a ssurance programs of the banks, and for allowing the international exc hange of placental blood between transplant centers. (C) 1998 Elsevier , Paris.