The Malta Independent 14 May 2025, Wednesday
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HIV-like virus suppressed in monkey experiment

Malta Independent Thursday, 14 November 2013, 13:19 Last update: about 12 years ago

Doctors may one day be able to control a patient's HIV infection in a new way: injecting swarms of germ-fighting antibodies, two new studies suggest.

In monkeys, that strategy sharply reduced blood levels of a cousin of HIV. The results also gave tantalizing hints that someday the tactic might help destroy the AIDS virus in its hiding places in the body, something current drugs cannot do.

The study results "could revolutionize efforts to cure HIV" if the approach is found to work in people, said a commentary published Wednesday by the journal Nature along with the monkey studies.

Antibodies are proteins in the blood that grab onto specific germs and mark them for elimination. People infected with HIV naturally make antibodies to fight the AIDS virus, but they are generally ineffective. The two new studies used lab-made versions of rare antibodies with unusual potency against HIV.

One study of rhesus monkeys showed a profound effect from a single injection of antibodies, said lead author Dr. Dan Barouch of Harvard and the Beth Israel Deaconess Medical Center in Boston.

The 18 animals had been infected with SHIV, a monkey version of HIV. In 13 animals, blood levels of SHIV became undetectable by standard tests within a week of the treatment. After the antibodies petered out, the virus came back. That happened one to three months after treatment.

In three monkeys with the lowest levels of SHIV before treatment, the virus didn't return during an observation period of up to eight months. Barouch said the animals were not cured, but the treatment had apparently improved their immune systems enough to keep the virus in check.

The two other monkeys started with the highest blood levels of SHIV. Treatment lowered those levels but not to the point where they were undetectable.

The second study in Nature, from the National Institutes of Health, showed encouraging results in a smaller group of monkeys.

In people, standard drugs routinely tamp down HIV to undetectable levels in the blood. But the antibody approach may someday help doctors attack virus that's hiding in infected cells, beyond the reach of today's drugs, said the Nature commentary by Dr. Steven Deeks of the University of California, San Francisco, and Dr. Louis Picker of the Oregon Health & Science University in Beaverton.

In theory, antibodies might activate the body's immune system to kill those infected cells, they wrote. Barouch's results hinted at such an effect, they noted. Virus levels dropped faster in the monkeys than they do when people get standard HIV drugs, and when the monkey virus returned, it generally didn't reach its pre-treatment levels. Barouch also found virus levels reduced in cells and tissues after treatment.

The findings of the two studies are "provocative" about prospects for attacking HIV's hiding places, Deeks said in a telephone interview.

"These studies raised more questions than they answered," he said. "But that's how science advances."

 

so-b?fn?q?s.0pt; font-family:"Verdana","sans-serif";mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";color:#333333;mso-fareast-language:EN-GB'> law and ethics at Oxford University, believes children couldn't possibly have the capacity to make an informed decision about euthanasia since even adults struggle with the concept.

 

"It often happens that when people get into the circumstances they had so feared earlier, they manage to cling on all the more," he said. "Children, like everyone else, may not be able to anticipate how much they will value their lives if they were not killed."

There are others, though, who argue that because Belgium has already approved euthanasia for adults, it is unjust to deny it to children.

"The principle of euthanasia for children sounds shocking at first, but it's motivated by compassion and protection," said John Harris, a professor of bioethics at the University of Manchester. "It's unfair to provide euthanasia differentially to some citizens and not to others (children) if the need is equal."

And Dr. Gerlant van Berlaer, a pediatric oncologist at the Universitair Ziekenhuis Brussels hospital, says the changes would legalize what is already happening informally. He said cases of euthanasia in children are rare and estimates about 10 to 100 cases in Belgium every year might qualify.

"Children have different ways of asking for things, but they face the same questions as adults when they're terminally sick," van Berlaer said. "Sometimes it's a sister who tells us her brother doesn't want to go back to the hospital and is asking for a solution," he said. "Today if these families find themselves (in that situation), we're not able to help them, except in dark and questionable ways."

The change in the law regarding people with dementia is also controversial.

People now can make a written declaration they wish to be euthanized if their health deteriorates, but the request is only valid for five years and they must be in an irreversible coma. The new proposal would abolish the time limit and the requirement the patient be in a coma, making it possible for someone who is diagnosed with Alzheimer's to be put to death years later in the future.

In the Netherlands, guidelines allow doctors to euthanize dementia patients on this basis if they believe the person is experiencing "unbearable suffering," but few are done in practice.

Dr. Patrick Cras, a neurologist at the University of Antwerp, said people with dementia often change their minds about wanting to die.

"They may turn into different people and may not have the same feelings about wanting to die as when they were fully competent," he said. "I don't see myself killing another person if he or she isn't really aware of exactly what's happening simply on the basis of a previous written request (to have euthanasia). I haven't fully made up my mind but I think this is going too far."

Penney Lewis, a professor and medical law expert at King's College London, agreed that carrying out euthanasia requests on people with dementia once they start to worsen could be legally questionable.

"But if you don't let people make decisions that will be respected in the future, including euthanasia, what you do is encourage people to take their own life while they have the capacity or to seek euthanasia much earlier," she said.

In the past year, several cases of Belgians who weren't terminally ill but were euthanized — including a pair of 43-year-old deaf twins who were going blind and a patient in a botched sex change operation — have raised concerns the country is becoming too willing to euthanize its citizens. The newest proposals have raised eyebrows even further.

"People elsewhere in Europe are focused on assisted dying for the terminally ill and they are running away from what's happening in Belgium," Lewis said. "If the Belgian statutes go ahead, this will be a key boundary that is crossed."

 
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