Human blood have been grown from embryonic stem cells for the first time during research that promises to provide an almost limitless supply suitable for transfusion into any patient. This could lead to trials of the blood within two years, and ultimately to an alternative to donations that would transform medicine.
If such blood was made from stem cells of the O negative blood type, which is compatible with every blood group but is often in short supply, it could be given safely to anybody who needs a transfusion. Stem-cell-derived blood would also eliminate the risk of transmitting the pathogens that cause hepatitis, HIV and Creutzfeldt-Jakob disease (CJD) through transfusions.
In other stem cell news, Massachusetts General Hospital (MGH) investigators have found that infusions of a particular bone marrow stem cell appeared to protect gastrointestinal tissue from autoimmune attack in a mouse model.
The research also has more immediate clinical promise for efforts to turn embryonic stem cells into other types of tissue, to treat conditions such as diabetes and Parkinson’s.
One of the biggest safety hurdles that must be cleared before stem-cell therapies enter clinical trials is the risk of uncontrolled cell growth causing cancer. Red blood cells, however, do not have nuclei that carry the genetic material that goes wrong in cancer, and thus should not present this danger. “This could be one of the biggest breaks for the early clinical application of embryonic stem cells,” Dr Lanza said. “There is still work to be done, but we could certainly be studying these cells clinically within the next year or two.”