Researchers are trying to develop artificial blood to eliminate dependence on blood donors and the risk of infectious disease transmission and blood-type rejection. French researchers are aiming to conduct the first human clinical trials of red blood cells harvested from stem cells. Many chemists are working to make artificial blood from diverse molecules, ranging from perfluorocarbons to hemoglobin, while some researchers are exploring stem cells to make safe blood without the need for donors. Luc Douay, a stem cell biologist from the University of Paris VI, and his wo-workers are developing fully mature human red blood cells from hematopoietic stem cells. This protocol requires one unit of cord blood to deliver between two and four units of transfusable red blood cells. Douay is continuously working to develop techniques for producing larger quantities of red blood cells from a smaller amount of stem cell media.