Salk Stem-Cell Research Shows Promise in Sickle-Cell Disease

Skin cells are used to generate what researchers call pluripotent stem cells, which can be manipulated to grow into almost any biological structure.

“Our findings set the stage for the development of (stem-cell based therapies) for devastating genetic disorders such as sickle-cell disease,” said Juan Carlos Izpisua Belmonte, the lead author of the study and the head of Salk's Gene Expression Laboratory.

The defective gene behind the disease and others, which reduce the blood's ability to carry oxygen, is known as HBB, but traditional stem cell generation and gene therapy has proven potentially unsafe, because unwanted genes may be introduced, according to Belmonte.

“We wanted to fix the mutation in such a way that it does not leave any unwanted traces in a patient's genome,” researcher Keiichiro Suzuki said.

Sickle-cell disease, affecting about 90,000 Americans, causes red blood cells to be malformed – sickle-shaped rather than round – and that leads to often painful circulatory problems. It is hereditary, affects mostly people of African descent and is caused by a defect in a gene underlying the production of hemoglobin, or oxygenated blood.

Sickle-cell disease is treatable and curable via stem cell or bone marrow transplants, but there is a high risk of the recipient rejecting donated cells or marrow, Belmonte said.

But because the stem cells are developed from the patient, the risk of rejection is vastly reduced.

The method will soon be tested on animals.