Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study IDs protein that inhibits HIV from growing in cell cultures

11.10.2006
How a harmless virus called GB Virus type C (GBV-C) protects against HIV infection is now better understood. Researchers at the Department of Veterans Affairs (VA) Iowa City Health Care System and the University of Iowa have identified a protein segment that strongly inhibits HIV from growing in cell models.

The team found that an 85-amino acid segment within a GBV-C viral protein called NS5A greatly slows down HIV from replicating in cells grown in labs. The study results will appear online this week in the Proceedings of the National Academy of Sciences.

The finding builds on earlier VA and UI work showing that people with HIV who also are infected GBV-C live longer than those infected only with HIV, said Jinhua Xiang, M.D., a VA research health scientific specialist, UI researcher and the current study's principal author.

GBV-C and its role in HIV infection have been studied for nearly a decade by Xiang, along with another study author Jack Stapleton, M.D., staff physician and researcher at the VA Iowa City Health Care System and professor of internal medicine at the UI Roy J. and Lucille A. Carver College of Medicine.

... more about:
»GBV-C »HIV »NS5A »Protein »T-cell »Xiang

"Identifying a specific protein made by GBV-C that inhibits HIV growth in cell culture strengthens the argument that GBV-C is responsible for the prolonged survival observed in several studies of HIV-positive people," Xiang said. "Understanding how the protein works may allow us to develop target-specific therapies that can mimic these effects and inhibit HIV.

"Potentially these novel therapies would have certain advantages over current drugs, as the newer therapies would target the cell in which HIV can replicate and not the virus directly. Therefore, HIV should have more difficulty developing resistance to the effects of this protein," Xiang added.

Xiang previously discovered that GBV-C grows in the same type of white blood cells, CD4 T-cells, that HIV grows in and ultimately destroys. HIV attaches to this T-cell by first landing on a receptor called CD4. Once it reacts with the receptor, HIV can enter the cell, multiply and destroy the T-cell, thereby causing immune deficiency.

"People with GBV-C have a slower rate of destruction of these T-cells," said Stapleton, who also is director of the Division of Infectious Diseases at the Iowa City VA and UI.

The current study shows that the newly identified protein, NS5A, inhibits HIV in part by decreasing the number of CD4 receptors available to HIV. With fewer places for HIV to "dock," less HIV enters the cells to inflict destruction.

However, Xiang cautioned, this is only part of the story, and the researchers must continue work to understand how the NS5A protein exerts its total effect.

"Before NS5A can be used for any kind of therapy, we need to further map it," Xiang said. "We need to zero in to see what region has the critical effect on HIV inhibition."

Once that is accomplished, the team will seek to develop small molecular drugs that mimic the inhibiting action.

Stapleton noted that GBV-C is not toxic to T-cells and is not associated with any human disease. As a result, the U.S. Food and Drug Administration does not require that blood donations be screened for this common virus.

Up to 3 percent of healthy blood donors in the United States have active GBV-C infection. An additional 12 percent have antibodies indicating past exposure at the time of donation. Because the GBV-virus is transmitted through bodily fluids, as is HIV, many HIV-positive individuals have evidence of past or present infection with GBV-C.

Stapleton and Xiang first began studying the GBV-C and HIV connection because they were skeptical of earlier studies published in the mid-1990s.

"It was a strange story," Stapleton said. "Who would have thought a virus floating around in a lot of people does not make them sick but could significantly influence survival in people with HIV?"

Becky Soglin | EurekAlert!
Further information:
http://www.uiowa.edu

Further reports about: GBV-C HIV NS5A Protein T-cell Xiang

More articles from Life Sciences:

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Chemists at FAU successfully demonstrate imine hydrogenation with inexpensive main group metal
22.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Chemists at FAU successfully demonstrate imine hydrogenation with inexpensive main group metal

22.05.2018 | Life Sciences

Asian tiger mosquito on the move

22.05.2018 | Life Sciences

Self-illuminating pixels for a new display generation

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>