Normal Lives

Researchers from St. Jude Children’s Research Hospital have reportedly used HIV to cure infants born with “bubble boy” disease — a remarkable example of hijacking a deadly virus for a new treatment.

“The children are cured,” researcher Ewelina Mamcarz toldNBC News. “They came to us as little infants, some of them as young as 2 months, with severe infections. Now they are home, living normal lives, attending daycare.”

Danger Everywhere

X-linked severe combined immunodeficiency (SCID-X1) is a rare genetic disorder caused by a mutation in the interleukin-2 receptor subunit gamma (IL2RG) gene.

People born with SCID-X1 lack a functioning immune system, which makes exposure to any germ potentially life-threatening. In fact, many children born with SCID-X1 die before their second birthday.

Gene Therapy

In a study published Thursday in the New England Journal of Medicine, the St. Jude’s team details how it developed a gene therapy to effectively cure 10 infants born with SCID-X1.

After collecting bone marrow samples from each patient, they used a modified version of HIV to place a non-mutated IL2RG gene into the patients’ stem cells. Then they dosed the patients with busulfan, a drug that helps make room for donor stem cells to grow, and returned the cells to the patients’ bodies.

Most were discharged from the hospital within a month.

“While longer follow-up is needed to assess any late effects of treatment,” researcher Mort Cowan said in a news release, “these results suggest most patients treated with this gene therapy will develop a complete durable immune response without side effects.”