Sickle cell disease refers to a group of genetic blood disorders mainly affecting people of African, Mediterranean, Middle Eastern, and Caribbean decent. Those with sickle cell disease carry the abnormal hemoglobin S in their red blood cells due to a mutation of the β-globin gene. Instead of having flexible, disc-shaped red blood cells, affected individuals have characteristic sickle-shaped, more rigid cells that cause disturbances in blood flow and tissue oxygenation.
Scientists have studied the disease for decades in search for a cure. The main approach to patients with sickle cell disease includes preventative methods to limit complications and to treat pain symptoms. Bone marrow transplants show promise; however, finding compatible, sickle cell–free donors is very difficult. Now, there may be new significant hope for patients with sickle cell disease.
Scientists from the Necker Children’s Hospital in Paris used gene therapy in a 13-year-old boy with multiple and severe complications from sickle cell disease. The treatment entailed harvesting the patient’s own bone-marrow cells and enriching for CD34+ hematopoietic stem cells. This was followed by myeloablative chemotherapy (to prepare the body to receive the modified CD34+ cells). They used a lentivirus vector to insert an antisickling version of the beta-globin gene into the CD34+ stem cells, which were then put back into the patient. This procedure produces modified CD34+ with new instructions to produce healthy hemoglobin.
The patient received red blood cell transfusions until a significant level of normal adult hemoglobin was detected. At fifteen months post-treatment, the patient continued to have high levels of the antisickling β-globin. There have been no sickle cell crisis events, and the patient was able to discontinue medications and monthly blood transfusions. At this time, it is not certain how long this treatment can last or if it represents the basis of a complete cure. However, these results provide great promise of a long-lasting or permanent treatment for sickle cell disease that does not require a bone-marrow donor.
HemaCare is proud to work with scientists who are researching treatments for painful and deadly diseases such as sickle cell disease. Contact us today at 877-397-3087 to learn more about our biomedical research products.
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