US
doctors in Philadelphia said they have saved a seven-year-old girl
who was close to dying from leukemia with a pioneering use of an unlikely ally:
a modified form of the HIV virus. After fighting her disease with
chemotherapy for almost two years and suffering two relapses, the young girl
“faced grim prospects,” doctors at Children’s Hospital of Philadelphia said.
So in February this year they agreed
to take her on in an experimental program that fought fire with fire.
Helped by a genetically altered HIV
virus — stripped of its devastating properties that cause AIDS — doctors turned
the girl’s own immune cells into a superior force able to rout the “aggressive”
leukemia.
The treatment of Emily Whitehead was
one of the very first of its kind and cannot yet be considered “a magic
bullet,” the hospital said. But in Emily’s case, it apparently worked
completely.
First, millions of the girl’s natural
immune system cells were removed. Then the modified HIV virus was used to carry
in a new gene that would boost the immune cells and help them spot, then attack
cancer cells that had previously been able to sneak in “under the radar,” the
hospital said on its website.
Finally the rebooted immune cells were
sent back in to do their work.
“The researchers have created a guided
missile that locks in on and kills B cells, thereby attacking B-cell leukemia,”
the hospital said.
Pediatric oncologist Stephan Grupp,
who cared for the girl, explained Tuesday that there was never any danger of
AIDS during the process.
“The way we get the new gene into the
T cells (immune cells) is by using a virus. This virus was developed from the
HIV virus, however all of the parts of the HIV virus that can cause disease are
removed,” he said in an email.
“It is impossible to catch HIV or any
other infection. What’s left is the property of the HIV virus that allows it to
put new genes into cells.”
During the treatment, Emily became
very ill and went into the intensive care unit, underlining how risky the
procedure can be. However, drugs that partly block the immune reaction were
administered, without interfering with the anti-leukemia action, and she recovered,
the hospital said.
The result was “complete” and best of
all, the doctors say, the boosted immune shield continues “to remain in the
patient’s body to protect against a recurrence of the cancer”.
“She has no leukemia in her body for
any test that we can do — even the most sensitive tests,” Grupp told ABC
television. “We need to see that the remission goes on for a couple of years
before we think about whether she is cured or not. It is too soon to say”.
NEW
YORK (AFP)

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