A team of researchers has successfully treated sickle cell disease in laboratory mice. The team used CRISPR-Cas9 techniques to fix the mutation that causes the disease. The details are in a paper that was just published in the journal Science Translational Medicine.
In sickle cell disease, an inherited gene mutation causes red blood cells to form abnormal sickle shapes. These cells are less functional, fail to produce hemoglobin, and cause serious blockages. The sickle cells are also less durable and die off early, leaving the patient severely anemic. There is no cure for the disease but blood transfusions and some medications can help treat symptoms. Sickle cell disease can lead to an early death and is a huge problem in African populations, though the disorder can affect anyone.
A huge team of researchers, including scientists from the Children’s Hospital Oakland Research Institute, collaborated to develop a treatment for patients with sickle cell disease. The team used CRISPR-Cas9, a gene editing technique, to remove the sickle cell mutation in hematopoietic stem cells. Hematopoietic stem cells are progenitor cells that will later develop into mature blood cells. The research team corrected the mutation and transplanted the cells back into mice with sickle cell disease. The cells survived for four months and produced normal hemoglobin. The researchers believe that if the cells survive four months, it’s a good sign that the gene therapy will work for a long time.
While still in the early testing stages, the researchers have hope for their new gene editing treatment. Doctors could treat a patient’s blood cells and re-infuse the corrected cells. This would at least reduce the severity of symptoms and may lead to a complete cure. Sickle cell disease is a serious, painful genetic disorder and a lasting treatment has the potential to help hundreds of thousands of patients.
DeWitt et al. Selection-free genome editing of the sickle mutation in human adult hematopoietic stem/progenitor cells. Science Translational Medicine (2016).