HIV based gene therapy cures immunodeficiency in infants
Scientists created a gene therapy that used the human immunodeficiency virus (HIV) to cure bubble boy disease.
Ten infants were cured of severe combined immunodeficiency (SCID)—also known as bubble boy disease—using a moderated version of HIV.
What is SCID?
Severe Combined Immunodeficiency is an immune deficiency. It affects the T- and B-lymphocytes and results in the onset of serious infections that can be fatal within the first few months of life. Children affected by SCID can also become ill from live viruses present in some vaccines.
Why was it named bubble boy disease?
In 1971, the case of David Letter—an infant affected with SCID—caught people’s attention. This boy lived in a germ-free, plastic chamber until his death at the age of 12. Thus, the disease was popularly known as bubble boy disease.
The science behind the cure
Babies that have SCID require high levels of care. If the disease is left untreated, they tend to die as infants.
Researchers at St. Jude Children’s Research Hospital in Memphis, Tennessee discovered a gene therapy that can help babies born with little to no immune protection have a fully functional immune system. They published their findings in The New England Journal of Medicine on April 18.
Children were enrolled in an ongoing clinical trial of infants newly diagnosed with SCID-X1, the most common type of SCID. Scientists formulated a gene therapy that involved collecting cells from a patient’s bone marrow. Then using a virus—an alternate version of the HIV—as a vector, a corrected copy of the gene was inserted into the patients through blood stems.
The experiment started two years ago and no side effects have been reported.
Not treatment, but a permanent cure
The best treatment so far has been a bone marrow transplant. Over 80 percent of the patients lack donors which endangers their life. On the other hand, this discovery is a cure.
“These patients are responding to vaccinations and have immune systems to make all immune cells they need for protection from infections as they explore the world and live normal lives. This is a first for patients with SCID-X1,” said first and corresponding author Ewelina Mamcarz, M.D., of the St. Jude Department of Bone Marrow Transplantation and Cellular Therapy.
Most patients were discharged from the hospital within a month’s time. In less than three months, their bodies generated immune cells. Four of them developed antibody responses to normal vaccinations.
Credit: St. Jude Hospital
Scientific discovery to profitability
St. Jude has signed an exclusive license with Mustang Bio – a gene therapy company. In just a few hours, the company’s shares grew by 200 percent. The duo is hoping to include the study for other genetic disorders.
Mustang Bio’s CEO, Manny Litchman said, “Key hurdles will be manufacturing and navigating the regulatory process.” The company must source supplies of the vectors to formulate the gene therapy.