Peripheral stem cells in bone marrow transplantation. Cord blood stem cell transplantation.

Since it was shown that the number of haematopoietic stem cells contained in one sample of cord blood was sufficient for engrafting children and adults, cord blood banking has developed world wide. Cord blood banking has several advantages, including availability of this source of stem cells, low viral infection rate at birth, speed of the search and the possibility of collecting cord blood in ethnic groups under-represented in bone marrow donor registries. Other possible advantages which require further study, include a low risk of acute graft-versus-host disease, even with some degree of HLA mismatch. More than 700 cord blood transplants have been reported worldwide. The Eurocord Registry has analysed 250 cases. Briefly, analysis of the clinical results has shown that related cord blood transplants give better results than unrelated cord blood transplants. Factors associated with better survival in related and unrelated transplants were younger age, diagnosis with better results in inborn errors and children with acute leukaemia in first or second remission. High number of nucleated cells in the transplant and recipient negative cytomegalovirus serology were also favourable risk factors for survival.