Lentiviral vectors for the treatment of Wiskott-Aldrich syndrome.

Inherited disorders affecting the blood-forming tissues could be treated if a gene could be transferred into stem cells capable of regenerating bone marrow and lymphoid organs and its expression regulated in differentiated cell populations. Molecular Therapy reports on new progress in the development of a vector for transferring a therapeutic gene for one such disorder, Wiskott–Aldrich syndrome (WAS), an X-linked disorder in which boys are variably affected with a triad of symptoms. Defects in the immune system render boys with WAS susceptible to infections, a low platelet count creates risk for serious bleeding, and recurrent skin rashes are problematic. Older boys may develop lymphoid cancer or, paradoxically, the immune system may turn on cells of their own bodies, resulting in an autoimmune disorder. Life expectancy is only 20 years. Bone marrow transplantation is curative, but many boys lack a matched donor and older boys are at high risk for transplant complications.