Cryopreserved cord blood cells are a potentially important alternative to bone marrow transplantation, but cord cells often provide inadequate numbers of stem cells for prompt reestablishment of hematopoiesis in adults. In October 15
Ohishi et al. investigated the effect of Notch signaling on human hematopoietic precursors. They observed that incubation of CD34+CD38- cells with immobilized Delta-1, together with fibronectin fragments and appropriate growth factors, induced a multiple-log increase in the number of human CD34+ cells and promoted early T cell differentiation. In addition, they showed that in immunodeficient mice, incubation of CD34+CD38- cells...