Allogreffe de sang placentaire chez l'adulte : actualités et perspectives

Hematopoietic stem cell transplantation is the choice treatment of many hematopoietic disorders. However, there is still no related or HLA-matched unrelated donor for one-third of the patients. Cord blood, which contains a lot of hematopoietic progenitors immunologicaly naive, represents not only an interesting alternative as hematopoietic stem cell source but also allows more HLA incompatibilities than the other sources. Promising results in children lead to develop cord blood transplantation in adults first of all in hematopoietic malignancies (acute leukemias and lymphoid diseases) and in a second time, in non-malignant diseases such as aplastic anaemia. The main problems for the development of this new strategy in adults are the poor number of cells per unit, the delay for hematopoietic recovery in comparison with other hematopoietic stem cell sources and, consequently higher transplant related mortality. In order to improve the results in adults, new strategies emerged. Double cord blood transplantation, expansion methods and intrabone injection of the graft will be reviewed here, as well as alternative transplantation strategies such as non-myeloablative conditioning.