Sangamo's gene editing tech fixes immune flaw in stem cell study

Researchers from Italy's San Raffaele Telethon Institute for Gene Therapy and Sangamo BioSciences ($SGMO) have used a gene editing technique to correct a genetic defect in stem cells from an individual with X-linked severe combined immunodeficiency.

X-linked severe combined immunodeficiency, or SCID-XI, is an inherited immune system disorder that appears almost exclusively in males. Investigators say the study supports the clinical use of this technology--called zinc finger nuclease-mediated gene insertion--for SCID-X1 as well as other immunodeficiencies and monogenic diseases, which result from abnormalities in a single gene occurring in all cells of the body.

Zinc finger nucleases, or ZFNs, are engineered DNA-binding proteins that enable targeted editing of the genome. The researchers note that the treatment effectively targeted a class of hematopoietic stem cells (HSCs) that are essential to fueling the long-term repopulation of bone marrow following a transplant. The results were published May 28 in Nature.

"The ability to accomplish targeted integration of a therapeutic gene into HSCs represents a major step forward in the quest for more precise and safe gene therapies," said Dr. Luigi Naldini, director of the San Raffaele Telethon Institute for Gene Therapy and a senior author on the paper, in a statement.

The news comes after Sangamo and collaborator Carl June at the University of Pennsylvania published data in The New England Journal of Medicine on the ZFN technique. T cell counts in HIV patients improved for weeks after researchers used the technology to tailor them to ward off the lethal virus.

Sangamo is also collaborating with Shire ($SHPG) to develop therapeutics for hemophilia, Huntington's disease and other monogenic diseases, and with Biogen Idec ($BIIB) for hemoglobinopathies, such as sickle cell disease and beta thalassemia.

- read the press release
- see the Nature abstract