Posted on: Fri 04-10-2013

Scientists have recorded two major breakthroughs within one week in their fight against Human Immuno-deficiency Virus (HIV)/Acquire Immune                 Deficiency Syndrome (AIDS).

A new study by researchers at the University of Cambridge,  England, United Kingdom (UK) published Tuesday in the journal BioMed Central revealed that a mutant of an immune cell protein called ADAP (adhesion and degranulation-promoting adaptor protein) is able to block infection by HIV-1.

The researchers, who were funded by the Wellcome Trust, believe that their discovery will lead to new ways of combating HIV.

The study is tiled "Immune adaptor ADAP in T cells regulates HIV-1 transcription and cell-cell viral spread via different co-receptors."

The Wellcome Trust is a global charitable foundation dedicated to achieving extraordinary improvements in human and animal health. It supports the brightest minds in biomedical research and the medical humanities.

Also, researchers from the Northwestern University, Illinois, United States, in another research published

September 16 in the Proceedings of the National Academy of Sciences (PNAS) found that new intravaginal ring filled with an anti-retroviral drug could help prevent HIV infection.

The paper' is titled "Intravaginal Ring Eluting Tenofovir Disoproxil Fumarate Completely Protects Macaques from Multiple Vaginal Simian-HIV Challenges."

Developed with support from the National Institute of Allergy and Infectious Diseases by Northwestern University visiting associate professor Patrick Kiser, the ring is easy to use, long lasting, and recently has demonstrated a 100 per cent success rate protecting primates from the simian immunodeficiency virus (SHIV). The device will soon undergo its first test in humans.

Until now, the proportion of women infected with HIV has been on the rise for a decade, in sub-Saharan Africa, women constitute 60 per cent of people living with disease. While preventative drugs exist, they have often proven ineffective, especially in light of financial and cultural barriers in developing nations.

Meanwhile, Professor Chris Rudd from the Department of Pathology, who led the research, said: "One exciting aspect about this new target for HIV intervention is that we should be able to fight HIV without compromising the ommune system's ability to battle infecticions."

HIV infections cause a severe and selective depletion of T- cells, a type of white blood cell that plays a major role in the immune system. Infections result when the HIV virus enters T-cells of the immune system by binding to the surface receptor CD4. Once it enters the cell, it replicates or reproduces itself rapidly, and then spreads to other T -cells by releasing the virus.

This spread can occur between an infected T-cell and an uninfected attached T-cell. The researchers found that an

ADAP mutant is able to interfere with HIV-1 infection by targeting two events, by reducing the replication of the virus,

and the contact between infected and uninfected T- cells.

Rudd added: "The ADAP mutant is potent in its interference of HIV-1 transmission because it targets simultaneously two critical events, viral replication and the spread of the virus from one Tcell to another. One therapeutic possibility is the reconstitution of infected individuals with T- cells expressing the mutant that are relatively resistant to HIV infection and which can react against the virus."

According the World Health Organisation (WHO), there are currently 353 million people living with HIY. Although the number of new HIV infections has dropped, it remains a major global public health issue. In the past three decades, it has killed more

than 25 million people.

Meanwhile, Kiser, an expert in intravaginal drug delivery who joined Northwestern from the University of Utah, where the research was conducted said: "After 10 years of work, we have created an intravaginal ring that can prevent against multiple HIV exposures over an extended period of time, with consistent prevention levels throughout the menstrual cycle."

Kiser is a new faculty member in Northwestern's Mccormick School of Engineering's Department of Biomedical Engineering and visiting associate professor of obstetrics and gynecology in the Feinberg School of Medicine. Previous studies have demonstrated that antiviral drugs can prevent HIV infection, but existing methods for delivering the drug fall short. Pills

must be taken daily and require high doses, vaginal gels that must be applied prior to each sex act are inconvenient, yielding poor usage rates.

The new ring is easily inserted and stays in place for 30 days. And because it is delivered at the site of transmission, the ring - known as a TDF-IVR (tenofovir disoproxil fumarate intravaginal ring) - utilises a smaller dose than pills.

The device contains powdered tonofovir, an anti-retroviral drug that is taken orally by 3.5 million Hiv-infected people worldwide, but that has not previously been studied topically. But the ring's strength stems from its unique polymer construction: its elastomer swells in the presence of fluid, delivering up to 1,000 times more of the drug than current intravaginal ring technology, such as NuvaRing, which are made of silicon and have release rates that decline over time.

The upcoming clinical trial, to be conducted in November at Albert Einstein College of medicine in New York, will evaluate the ting in 60 women over 14 days. The trial will assess the ring's safety and measure how much of the drug is released and the properties of the ring after use .

Other drugs could potentially be integrated into the ring, such as contraceptives or antiviral drugs to prevent other sexually transmitted infections - a feature that could increase user rates, Kiser said.

“The flexibility to engineer this system to deliver multiple drugs and change release rates is extraordinary and could have a significant impact on women's health he said.

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