Transplanting blood stem cells (often called bone-marrow transplant) provides a life-saving therapy for thousands of patients each year. However, obtaining a matching donor can be very difficult, especially for patients of certain ethnic groups or mixed ethnicity. Umbilical cord blood could provide one solution to this problem, but most cord blood samples contain too few cells to transplant into an adult. We have developed molecules that, when added to stem cells isolated from umbilical cord blood, expand the number of stem cells dramatically. We are optimizing the molecules to increase stem-cell production and are testing these expanded cells in transplant models. Our goal is to obtain patentable molecules and processes that can be used to expand stem cells for research and therapeutic uses.