Could human blood be grown in a laboratory? In August researchers demonstrated a method of using human embryonic stem cells (hESC) to generate functional, oxygen-carrying erythrocytes
, or red blood cells, in sufficient quantities to be used for transfusion.
The cells are not quite the same as natural red blood cells. The proteins in them are characteristic of fetal and embryonic cells rather than of mature erythrocytes, and the authors take care to call them “erythroid cells” rather than true erythrocytes. Still, the new cells have no nucleus, which is a distinguishing feature of mature red blood cells.
Bone marrow cells and newborn babies’ umbilical cords are being considered as sources for laboratory blood, but those are limited in quantity and useful only to the donor, while hESCs could prove to be an unlimited source of universally transfusable blood.
“The goal is not to put the Red Cross out of business,” says Robert Lanza, chief scientific officer at Advanced Cell Technology, the company that developed the process. “But with this technology, you’d never run out of blood in a crisis.”