I met two-year-old Jameson Golliday on a patch of lawn in Bloomington, Illinios. He had blue eyes, dark hair, and wore a striped shirt, shorts, and Crocs. He followed his mother, Jennifer, 31, as she pushed a wheelbarrow around the yard, picking up sticks. The neighbors were burning lawn debris and fly ash was swirling in the sky, big fluffy flakes, falling lightly all around us. Jameson’s brother, Shawn, 5, was wearing a Star Wars t-shirt and tossed a plastic sword to his grandfather. There was the bat-bat of plastic, and things quickly turned Galactic.
Jamie and his mother retreated to a quiet spot in the yard. She lets him run free in the backyard, but he can’t play with other children or touch high-contact surfaces such as playground equipment.
“It’s super sad,” Jennifer told me. “He sees kids off in the distance and points at them. I know he wants to interact.”
Jamie was born with X-SCID, or "bubble boy disease," which means he has no immune system. At birth he had no mature T-cells, the rugged soldiers of the immune system that sense and fight infections, due to mutations in the IL-2 gene on his X-chromosome, which rendered the gene non-functional.
David Vetter was the most famous bubble boy. In the 1970s and 1980s he lived in a bubble, using only items sterilized with 140-degree ethylene oxide gas. Doctors tried a bone marrow transplant from his sister to introduce working T-cells into his system. But the Epstein-Barr virus was sleeping in the marrow, and it triggered the growth of many tumors. Vetter died at age 12.
When Jamie was born he had a small cough, but unlike most colds, it didn’t go away, not for a year. His mom noticed a bump on his hip one day, which turned out to be a cluster of B-cells unsuccessfully trying to fight an infection. This clustering looked like cancer, and caused doctors to diagnose Jamie with diffuse B-cell lymphoma, which is very uncommon in infants. Later tests revealed Jamie’s illness for what it was—X-SCID.
In April 2012, not long after Jamie’s diagnosis, Jennifer and Jamie, then 1, took a medical jet to Cincinnati Children’s Hospital, so that Jamie could participate in a trial for gene therapy—a treatment that wasn’t available in David Vetter’s time. Jennifer improvised a ‘bubble stroller’ out of a rain tarp and a baby stroller, to transport him back and forth between the hospital and the Ronald McDonald House where they stayed in Cincinnati. Inside, he wore a surgical mask.
Doctors drew some of Jamie’s bone marrow, and dosed it with a virus carrying the IL-2 gene. The virus serves as a tiny pilot, carrying the payload of the IL-2 gene into his cells, installing it in his genome. That gene builds a protein called a cytokine, which sends a signal telling T-cells to mature. Weeks after Jamie received his shiny new IL-2 gene, a blood test showed 13 mature T-cells per microliter, where before he’d had none.
Jamie’s cold soon vanished. “It was our first victory,” Jennifer said.
The ash continued to fall. Jamie quietly colored with chalk on the driveway. Shawn’s grandfather was on the defense in the light saber fight, and the Galactic battle shifted to the front yard. Shawn had become oppositional since he had to leave school when a classmate became sick. He couldn’t risk bringing a cold home to his brother. But Shawn will soon be back in school. With Jamie’s T-cell count on the rise, he could cautiously explore his grandfather’s yard, loose of masks and bubble strollers,
Jamie still wasn’t allowed to interact with people outside his family. But still he romped up to me, and thrust his tiny arm skyward.
“What’s he doing?” I asked his mom.
“I think he wants to hold your hand,” she said.
The First Tools
In 1982, Richard C. Mulligan was at MIT when he deleted an element in a gamma retrovirus called psi, which was used by the virus to package itself to travel to new places. He gutted the virus of its contents, and in its place he installed a human gene. He had developed the first tool for genetic engineering: a virus with a one-way ticket to the human genome that could not move to a new address. It would sit tight and publish copies of the gene he installed, and its first task would be to treat X-SCID patients.
But problems soon arose. Mulligan had no way to tell the virus where to install. It might integrate near a cell cycle gene and boost the signal for cell division, leading to uncontrolled cell growth. By the year 2000, twenty X-SCID patients had been treated with the tool, but five of those patients developed leukemia-like conditions. One of those patients died.
David A. Williams, chief of hematology at Boston Children’s Hospital, was one of Mulligan’s post-doc students at MIT. By the time leukemia developed in the X-SCID patients, he was working at Cincinnati Children’s with Christopher Baum, and the two scientists thought up an elegant solution.