Interest of cord blood stem cells.

Interest in cord blood stem cells was raised because of the possibility, now realised, of their use in clinical transplantation. The availability of only limited numbers of stem cells in cord blood compared to bone marrow or peripheral blood apheresis after cell mobilisation, led to experimental approaches that first aimed to characterise and then manipulate the stem cells present in cord blood. Their phenotypical and functional characteristics are not identical to those of stem cells in the bone marrow or those cells mobilised into the circulation. The cells selected for phenotype plus Go status show the higher capacity to generate progenitor cells in vitro and will offer the opportunity for mechanistic studies of stem cell self-renewal and proliferation. Another important field of exploration is to investigate the capacity of stem cells in cord blood for differentiation to tissues other than haemopoietic and to establish whether haemopoietic and non-haemopoietic lineages originate in truly multipotential cells or in cells coexisting in cord blood, which have already been limited to differentiation into specific tissue.