Laboratory generated blood successfully injected into human subject.

The Chicago Tribune (12/29) reports that according to a study in published in the journal Blood, "red blood cells generated in a lab have been successfully injected into a human volunteer for the first time." French researchers extracted "hematopoetic stem cells from a volunteer's bone marrow" and used various growth factors to induce the cells to differentiate into red blood cells (RBC). "After five days, 94 to 100 percent of the cells remained in circulation, while after 26 days, 41 to 63 percent remained -- a survival rate comparable to normal red blood cells. The cultured blood cells also gave every indication of being safe to use. ... They behaved like normal red blood cells, binding to oxygen and releasing it." While this result is promising, researchers note that "next challenge is to scale up production to a point where the cultured blood cells can be made quickly and cheaply in sufficient quantities for blood transfusions."