Stem Cells seem to be safe in treating Eye Disease

Extraordinarily versatile, embryonic stem cells can differentiate into any tissue of the body an ability that has thrown up tantalizing hopes of using them to replace tissue lost through disease, accident or war. Embryonic stem cells transplanted into 18 patients with deteriorating eyesight restored some vision in more than half the volunteers, the longest study into the fledgling technology. Stem cells derived from embryos “could provide a potentially safe new source of cells for the treatment of various unmet medical disorders requiring tissue repair or replacement. But scientists have had to face two major obstacles. One is that donated stem cells, provoking an immune response, can be rejected by the body or cause cancer. The eye is considered a promising site for transplants as it is located at a shield called the blood-ocular barrier where there is not a strong immune response.