Eight children born without a working immune system, known as "bubble boy" disease, have been cured by gene therapy made with HIV, US scientists have revealed.
Children born with X-linked severe combined immunodeficiency (SCID-X1) — a rare genetic illness sometimes called "bubble boy" disease because of the measures taken to protect patients — usually die early in life.
Their bone marrow does not produce the protein needed to boost their immune system because of a mutation of the interleukin-2 receptor sub unit gamma (IL2RG) gene.
Scientists at the St Jude Children's Research Hospital in Memphis, US, collected bone marrow from the children, inserted the correct copy of the IL2RG gene into the DNA as well as a disabled relative of HIV — better suited to insert genes into cells that are not actively dividing.
The children then received chemotherapy drugs to prevent leukaemia, a possible side-effect, before having the modified cells infused back into them.
Most patients were discharged from the hospital within one month.
"These patients are toddlers now, who 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," Ewelina Mamcarz, from St Jude Department of Bone Marrow Transplantation and Cellular Therapy and one of the study's authors, said in a statement.
"This is a first for patients with SCID-X1,” she added, referring to the most common type of the disease.
The research was published on Thursday in the New England Journal of Medicine.