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Thu Jun 26, 5:48 PM ET
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By Alison McCook
NEW YORK (Reuters Health) - All researchers
investigating potential vaccines to prevent HIV need to work together to speed
up the process, according to a report released Thursday by an international
group of AIDS experts.
In the journal Science, the authors urge all HIV vaccine investigators to
form a network of worldwide HIV vaccine development centers, each of which
would help coordinate activities in one aspect of the research.
In that way, researchers can work together, sharing information and
learning from each other's experiences, a report author told Reuters Health.
"There's an urgent need to accelerate the pace of HIV vaccine
development," said Dr. Helene Gayle of the Bill and Melinda Gates
Foundation in Seattle.
"A more collaborative approach to research would very likely help to
accelerate the speed and also the efficiency," Gayle added.
Problems in efficiency are likely one of the main reasons why years of
worldwide research have not yet yielded a viable HIV vaccine, Gayle said,
along with the fact that the virus itself is biologically complex.
If this new proposed model for vaccine development works, Gayle noted that
the lessons learned could be applied to other vaccine efforts, such as those
aimed at fighting major killers like tuberculosis and malaria.
Currently, she said, researchers working toward an HIV vaccine share
information with each other, but not to the extent recommended by the new
report, which urges researchers to pool all of their results and work
together.
She noted that she and her colleagues do not envision the vaccine network
as a "superstructure," but instead use the Human Genome Project as a
model -- in which researchers worked individually on different aspects of the
project, and shared their results.
Obstacles to this include the very nature of research itself, which is
often competitive, Gayle noted.
In addition, companies often invest in research with the plan of making
money off of the fruits of their efforts, and consequently prefer to keep some
results secret in order to protect their proprietary information.
In order to overcome these barriers and establish a collaborative global
network to develop an HIV vaccine, researchers will need to come up with new
ways to conduct their work so that sharing and working together does not crush
scientific creativity and the potential for profits, Gayle said.
Other obstacles to such a collaborative effort include the fact that many
vaccine researchers are working on opposite sides of the globe, and do not
have many resources, according to Gayle.
"Greater resources will be needed to do this more efficiently, more
effectively," she said.
She noted that the additional money could come from the public and private
sector, as well as foundations.
In the report, Gayle and her colleagues also recommend that most of the
advanced trials of vaccine candidates be conducted in developing countries in
Africa and Asia, which have been hardest hit by the HIV pandemic.
"In this case, the benefit is greatest for the countries in which the
trials will eventually be done," Gayle said.
SOURCE: Science 2003;300.
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Thu Jun 26, 1:59 PM ET
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By Maggie Fox, Health and Science Correspondent
WASHINGTON (Reuters) - Researchers said on
Thursday they had figured out how a rare antibody sees past the disguises of the
AIDS virus -- a finding that may lead to a vaccine that will finally work
against the killer microbe.
The antibody, taken from a unusual patient whose body can resist the virus,
recognizes and attacks the human immunodeficiency virus, unlike most of the
body's defenses.
"Nothing like this has ever been seen before," Ian Wilson of The
Scripps Research Institute in La Jolla, California, who led the research, said
in a statement.
AIDS has killed 25 million people around the world and is projected to kill
80 million by 2010. The only real hope of fighting the incurable virus is a
vaccine, but efforts so far have flopped although dozens of vaccines are being
tested.
Antibodies are an important arm of the body's defenses against germs. They
are usually able to recognize an invader by structures on its surface, called
antigens, and can either call in help, or neutralize it themselves by pasting
themselves against it.
Most vaccines in use today stimulate the production of neutralizing
antibodies.
The human body makes plenty of antibodies against HIV, but the virus
disguises itself with human sugars.
One antibody seems to be able to see past this ruse. Called 2G12, it was
found by Austrian researchers a decade ago in a patient who seemed to resist
acquired immune deficiency syndrome -- the condition caused as HIV destroys the
immune system over time.
Writing in the journal Science, Wilson and colleagues said they had figured
out how 2G12 does it.
It recognizes that while HIV is covered up with human sugars, they are not
arranged in a human-like way.
The antibody does this with a special structure of its own, which Wilson and
colleagues, including a team at Oxford University in Britain, have crystallized
and imaged.
"The Fab (antigen recognition) arms are interlocked," said Scripps
researcher Dennis Burton, who worked on the study. "That is a unique
arrangement, and it is good for recognizing a cluster of shapes like sugars on a
virus."
Now what needs to be done is to use the structure of the antibody as a
template to design an antigen to stimulate the production of 2G12 or another
antibody that will neutralize HIV, the researchers said.
The approach might also work for making vaccines against other germs, said
Wilson. "Can we now use this to engineer antibodies with higher affinity
against other antigens or clusters of antigens?" he asked.
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Mon Jun 23, 5:58 PM ET
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By Keith Mulvihill
NEW YORK (Reuters Health) - Preliminary research
is zeroing in on certain protein patterns in blood cells that may be a sign an
HIV-infected patient is at risk of dementia, according to a study released
Monday.
"This study is a first and early work to determine if specific protein
fingerprints can be obtained from blood cells that would predict cognitive
dysfunction in HIV-1 infected people," said lead investigator Dr. Howard E.
Gendelman. The findings are exciting, according to Gendelman, because they open up new
areas of research into neurological diseases. Until now, doctors have relied on
clinical examinations and brain-imaging techniques to diagnose brain disease,
including HIV-associated dementia. The new study offers the hope that a blood
test may one day help spot early disease.
Late-stage AIDS patients often suffer from HIV-associated dementia, a
progressive degeneration of the brain, which occurs as HIV invades the central
nervous system. The condition induces steady, incremental losses in both mental
and motor function, explained Gendelman, who is with the University of Nebraska
Medical Center in Omaha.
About ten percent of HIV-infected individuals have severe cognitive disease,
Gendelman said, although a higher percentage experience other neurological
complications, including a condition called neuropathy.
In the study, the team of researchers used a relatively new technique called
"proteomics protein fingerprinting" to evaluate protein activity in
infection-fighting white blood cells. The researchers looked at blood samples
from 21 HIV-positive Hispanic women, some with and some without dementia. Their
findings were compared to similar blood samples collected from 10 healthy
Hispanic women without HIV.
In all, the team of researchers, which included co-investigator Dr. Loyda M.
Melendez of the University of Puerto Rico Medical Sciences Campus in San Juan,
evaluated 177 proteins. Of that group, 38 proteins exhibited different activity
levels in women with dementia and those without dementia, according to the
report.
"The idea that a blood test can be used with some precision to aid more
conventional testing is quite novel and may prove to be important if further
defined," Gendelman told Reuters Health.
Still, protein patterns may change over time so patients need to be followed,
he said.
"Groups of proteins may be predictive but others may actually be
involved in the disease process," said Gendelman. "Differentiating
these groups of proteins is important."
"The data is preliminary and much more need be done before it can be
used in any clinical setting," he added.
Gendelman pointed out that there is another part of this research that is
equally important in a different way.
"It shows that circulating blood cells of the monocyte-macrophage
lineage -- the blood's scavenger cells -- are involved in the pathogenic process
of disease," he told Reuters Health.
"So why is this important? Unlike other types of (brain inflammation)
where virus infects nerve cells -- like herpes, and rabies for example -- HIV-1
infects immune cells that enter into the brain and, once inside, cause
considerable injury through indirect mechanisms," said Gendelman.
If the researchers can gain a better understanding of how these indirect
mechanisms work, better ways may be found to treat the disease process, he said.
SOURCE: Neurology 2003;60:1931-1937.
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Tue Jun 24, 6:21 PM ET
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NEW YORK (Reuters Health) - A large percentage of gay and bisexual men say they have had unsafe sex in recent months, putting themselves at risk of HIV and other sexually transmitted diseases, a new study has found.
Among nearly 4,300 gay or bisexual men in six U.S. cities, around half said they had had unprotected anal sex during the past six months, researchers report in the American Journal of Public Health.
The findings "emphasize the continued need for effective behavioral strategies designed to prevent HIV infection among men who have sex with men," write Dr. Beryl A. Koblin, of the New York Blood Center in New York City, and colleagues.
Their results are based on interviews with 4,295 gay or bisexual men participating in the ongoing EXPLORE study, which is aiming to identify risk behaviors that may be fueling HIV transmission in the U.S.
Every six months the study participants undergo counseling regarding their sexual behavior and get tested for HIV and other STDs.
All of the men were HIV-negative at the start of the study and reported that they had had anal sex during the six months prior to the study, which began in 1999.
Overall, men who said they'd had multiple sexual partners in recent months were no more likely to have used a condom than those who said they had only one primary partner -- a finding Koblin's team says is "of particular concern" since the former group is at increased STD risk.
In addition, unprotected anal sex was much more common when drugs and alcohol were involved, the researchers found.
The HIV epidemic among gay and bisexual men in the U.S. "continues to be a major public health issue," Koblin's team writes.
"Our findings," they conclude, "support the continued need for effective intervention strategies for men who have sex with men that address relationship status, (HIV status) of partners and drug and alcohol use."
SOURCE: American Journal of Public Health 2003:93:926-932.
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Thu Jun 26, 2:49 PM ET
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NEW YORK (Reuters Health) - Blacks, Hispanics, heterosexuals, and the less educated who are HIV-infected are the least likely to find out about their diagnosis early on, the U.S. Centers for Disease Control and Prevention (CDC) reported Thursday.
These groups of people should be targets for education regarding the importance of early HIV testing, Dr. Eyasu Teshale, a CDC medical epidemiologist, told Reuters Health.
"These findings were not so surprising, because we have other studies that show similar findings," he said.
The results, released just before the 9th annual National HIV Testing Day on Friday, appear in the CDC's Morbidity and Mortality Weekly Report. Sponsored by the National Association of People with AIDS, the theme of the campaign this year is "Take the Test, Take Control."
In the study, Teshale and colleagues analyzed data from interviews conducted at 16 U.S. sites. Of those surveyed, 72 percent were men, 56 percent were black, 22 percent were white, and 19 percent were Hispanic.
Early testers were defined as people who had their first positive HIV test five years or more before the diagnosis of AIDS or who spent five years or more without a diagnosis of AIDS after their first positive test. Late testers were those who had their first positive HIV test one year or less before the diagnosis of AIDS.
Compared with early testers, late testers were significantly more likely to be black or Hispanic, to have been exposed to HIV through heterosexual sex, to have a high school or lower education, and to have had a previous negative HIV test before their first positive test.
Late testers were most likely to seek testing due to illness (65 percent), while early testers sought the test because they felt they were at risk (29 percent) or because they were interested in knowing their HIV status (19 percent).
"We need to educate and inform people, especially those that are at risk for HIV infection, that the test is available both confidentially and anonymously," Teshale said.
Especially concerning, according to Teshale, is the finding that roughly half of those surveyed with AIDS had their first positive HIV test one year or less before being diagnosed with AIDS.
The fact that early testers were more likely than late testers to be diagnosed via anonymous testing (22 percent vs. 8 percent) attests to the importance of having anonymous HIV testing available, according to the CDC.
The CDC estimates that one in four HIV-infected individuals are currently unaware of their infection and therefore are not receiving services they need to stay healthy and to protect their partners.
SOURCE: Morbidity and Mortality Weekly Report 2003;52:581-586.
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Thu Jun 26, 4:24 PM ET
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FLORENCE, Italy (Reuters Health) - An early-phase trial of a vaccine to prevent HIV transmission from mother to infant will begin at the end of October, top HIV researchers said this week.
The announcement came at an international meeting in Rome organized by the Italian parliament's Culture Commission.
Created under the U.N.-supported World Foundation for AIDS Research and Prevention, the pediatric vaccine initiative will be administered in Africa, where each year about 600,000 newborns are infected with HIV by their mothers.
Mother-to-child transmission can occur during labor and delivery or through breastfeeding.
The "Families First Africa" post-exposure vaccine is the joint effort of Dr. Robert Gallo, director of the Institute of Human Virology in Baltimore; Dr. Luc Montagnier, president of the World Foundation for AIDS; and Dr. Vittorio Colizzi, of Rome's Tor Vergata University.
It is based on synthetic HIV peptides -- small proteins -- that will be incorporated into the BCG vaccine used to protect against tuberculosis.
Phase I of the study, to evaluate the vaccine's safety, should begin at the end of October in Baltimore and involve 30 healthy volunteers.
"By the first months of 2004 we should be able to start phase I clinical trials on newborns in the West African countries of Burkina Faso, Cameroon and Ivory Coast. We hope to be able to report the first results by June 2004, " Colizzi told Reuters Health.
The Italian government has set aside $2 million to fund the program.
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Fri Jun 27, 7:41 AM ET
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Generic
More than two decades into the AIDS epidemic, few medical professionals would dispute the importance of HIV testing. Yet too often, doctors allow patients at risk to walk out the door without being offered an HIV test -- with potentially grave consequences to patients and their loved ones.
A quarter of the roughly 1 million Americans living with HIV don't know they are infected. An important way to address this is for those of us in the medical community to become more active in offering patients voluntary HIV testing and the services that accompany it.
Testing is the first step toward getting people with HIV infections the care and treatment they need. It also is a chance for them to receive counseling on how to protect their partners, which is essential in reducing HIV infections. HIV testing in medical settings won't solve the AIDS crisis alone because many people at risk do not have access to health care. But for those who do enter our offices, we must get them tested -- especially African-Americans and other people of color, who are at greatest risk.
Of course, there are challenges to making HIV testing widely available in medical settings. After more than 20 years as an obstetrician and gynecologist in Houston, I've encountered many of them. Offering HIV testing and counseling takes time -- a luxury we don't have. For many physicians and patients, talking about testing also means overcoming discomfort with discussing sex, infidelity and drug use.
Fortunately, these problems are not insurmountable. Nurses and other staff can and often do share in counseling responsibilities. Public health officials are streamlining counseling requirements so they meet informed-consent guidelines but don't hinder testing. New rapid testing makes it possible to administer a test and provide the preliminary result in one office visit. And training programs help medical professionals become more comfortable with HIV testing and counseling. In other words, there can be no excuses. As physicians, we must be part of the solution.
Today is National HIV Testing Day, and many Americans are hearing a potentially lifesaving message: ''Get tested!'' We in the medical community should also hear it loud and clear.
L. Natalie Carroll, M.D., is president of the National Medical Association, which represents African-American physicians.