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.”
Grupp said on the Children’s Hospital of Philadelphia website that 
cell therapies might eventually replace the more costly, painful bone 
marrow transplant treatment, a standard last-ditch defense against 
cancer.
“I’ve been meeting with families to discuss bone marrow transplant 
for 20 years,” he said. “In almost every meeting, I say that bone marrow
 transplant is very hard and that if we had an alternative for children 
at that point in treatment, I would be delighted to put myself out of 
business. And for the first time, we’re seeing how that might actually 
happen.”
Source: AFP

 
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