Blood cells grown from stem cells

Associated Press

WASHINGTON — For the first time, researchers have used embryonic stem cells to produce human blood cells, a step that could lead to a new source of cells for transfusion and other therapies.

Primitive human blood cells, known as hematopoietic precursor cells, were produced from human embryonic stem cells by researchers at the University of Wisconsin, led by James A. Thomson.

This is the first time human blood cells have been developed from embryonic stem cells, said Dan S. Kaufman, one of the authors of the study appearing in today's issue of Proceedings of the National Academy of Sciences.

During development, stem cells transform into heart, muscle, brain, skin or other tissue. Researchers hope that by guiding this transformation in the laboratory, they can coax stem cells to make new cells that could be used to treat a number of diseases.

Kaufman stressed that it will take years before they can be developed to the point of use in people.