DESCRIPTION (provided by applicant): With the goal of overcoming the significant delay in neutrophil recovery that occurs following transplantation with umbilical cord blood (CB), we have successfully developed a novel and clinically feasible methodology utilizing an engineered Notch ligand for the ex vivo generation of increased numbers of CD34+ cells. A Phase I clinical trial utilizing Notch-mediated expanded CB progenitors in patients undergoing a myeloablative cord blood transplant (CBT) is currently underway. Results from this trial have not only demonstrated the safety of this approach, but more importantly have for the first time demonstrated that rapid myeloid engraftment can be achieved following infusion of ex vivo expanded hematopoietic progenitors. A significant reduction in median time to an absolute neutrophil count of 500/

PROJECT NARRATIVE Patients undergoing a cord blood transplant, who are often of minority or mixed ethnicity background, are at increased risk of infection and early death following the transplant due to the significant delay in white blood cells recovery (in particular, neutrophils) that these patients experience. However, using a novel culture methodology, we have demonstrated for the first time the ability to generate increased numbers of cells from a single unit of cord blood that are capable of rapid neutrophil recovery when infused in the clinical setting. Further development of this product to confirm our initial promising results requires additional clinical trials that, if successful, could change the way cord blood transplantation is performed.