Navigation Links
Unexpected find opens up new front in effort to stop HIV
Date:1/22/2011

HIV adapts in a surprising way to survive and thrive in its hiding spot within the human immune system, scientists have learned. While the finding helps explain why HIV remains such a formidable foe after three decades of research more than 30 million people worldwide are infected with HIV it also offers scientists a new, unexpected way to try to stop the virus.

The work by researchers at the University of Rochester Medical Center and Emory University was published Dec. 10 in the Journal of Biological Chemistry.

It's thanks largely to its ability to hide out in the body that HIV is able to survive for decades and ultimately win out against the body's relentless immune assault. One of the virus's favorite hiding spots is an immune cell called a macrophage, whose job is to chew up and destroy foreign invaders and cellular debris.

For more than 15 years, Baek Kim, Ph.D., has been fascinated by HIV's ability to take cover in a cell whose very job is to kill foreign cells. In the last couple of years Kim, professor of Microbiology and Immunology at the University of Rochester Medical Center, has teamed with Emory scientist Raymond F. Schinazi, Ph.D., D.Sc., director of the Laboratory of Biochemical Pharmacology at Emory's Center for AIDS Research, to test whether the virus is somehow able to sidestep its usual way of replicating when it's in the macrophage.

The pair found that when HIV faces a shortage of the molecular machinery needed to copy itself within the macrophage, the virus adapts by bypassing one of the molecules it usually uses and instead tapping another molecule that is available.

Normally, the virus uses dNTP (deoxynucleoside triphosphate, the building blocks for making the viral genetic machinery) to get the job done, but dNTP is hardly present in macrophages macrophages don't need it, since they don't replicate. But macrophages do have high levels of a closely related molecule called rNTP (ribonucleoside triphosphate), which is more versatile and is used in cells in a variety of ways. The team found that HIV uses primarily rNTP instead of dNTP to replicate inside macrophages.

"The virus would normally just use dNTP, but it's simply not available in great quantities in the macrophage. So HIV begins to use rNTP, which is quite similar from a chemical perspective. This is a surprise," said Kim. "The virus just wants to finish replicating, and it will utilize any resource it can to do so."

When the team blocked the ability of the virus to interact with rNTP, HIV's ability to replicate in macrophages was slashed by more than 90 percent.

The work opens up a new front in the battle against HIV. Current drugs generally target dNTP, not rNTP, and take aim at the infection in immune cells known at CD4+ T cells. The new research opens up the possibility of targeting the virus in macrophages where the virus is out of reach of most of today's drugs.

"The first cells that HIV infects in the genital tract are non-dividing target cell types such as macrophages and resting T cells" said Kim. "Current drugs were developed to be effective only when the infection has already moved beyond these cells. Perhaps we can use this information to help create a microbicide to stop the virus or limit its activity much earlier."

Kim notes that a compound that targets rNTP already exists. Cordycepin in an experimental compound, derived from wild mushrooms, that is currently being tested as an anti-cancer drug. The team plans to test similar compounds for anti-HIV activity.

"This significant breakthrough was unappreciated prior to our paper. We are now exploiting new anti-HIV drugs jointly based on this novel approach that are essentially not toxic and that can be used to treat and prevent HIV infections," said Schinazi, who has developed several of the drugs currently used to treat HIV patients.


'/>"/>

Contact: Tom Rickey
tom_rickey@urmc.rochester.edu
585-275-7954
University of Rochester Medical Center
Source:Eurekalert

Related medicine news :

1. MIT researchers discover an unexpected twist in cancer metabolism
2. Unexpectedly small effects of mutations in bacteria bring new perspectives
3. Youth adapt faster than seniors to unexpected events
4. Aegis of Bellevue Opens With Outstanding Attendance
5. St. Josephs Hospital-North Opens in North Tampa
6. Children's National Medical Center Opens Remaining Floors of Patient Tower
7. Leading U.S. Infertility Practice Opens Boston IVF The Maine Center in Portland, Helping Build Families in Maine
8. B2B Appointment Setting/Lead Generation Innovator Intelemark Opens New Office in Northeast
9. With Launch of a Rocket Composter, Northwest State Community College opens a new frontier in green technology in the US.
10. UniqueU Medical Weight Loss Program Opens Cincinnati Location
11. CDI College Opens a New Campus in Richmond
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... June 25, 2016 , ... ... non-athletes recover from injury. Recently, he has implemented orthobiologic procedures as a method ... —Johnson is one of the first doctors to perform the treatment. Orthobiologics are ...
(Date:6/24/2016)... ... 2016 , ... Those who have experienced traumatic events may suffer from a ... such as drug or alcohol abuse, as a coping mechanism. To avoid this pain ... following a traumatic event. , Trauma sufferers tend to feel a range of emotions, ...
(Date:6/24/2016)... ... June 24, 2016 , ... Global law firm Greenberg Traurig, P.A. announced that ... chosen by their peers for this recognition are considered among the top 2 percent ... special honors as members of this year’s Legal Elite Hall of Fame: Miami ...
(Date:6/24/2016)... ... June 24, 2016 , ... People across the U.S. are sharpening their pencils ... an essay contest in which patients and their families pay tribute to a genetic ... 2016 National Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. ...
(Date:6/24/2016)... Maryland (PRWEB) , ... June 24, 2016 , ... ... Angels is actively feeding the Frederick area economy by obtaining investment capital for ... over the past 2½ years that have already resulted in more than a ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Roche (SIX: RO, ROG; ... for its Elecsys BRAHMS PCT (procalcitonin) assay as a ... septic shock. With this clearance, Roche is the first ... integrated solution for sepsis risk assessment and management. ... infection and PCT levels in blood can aid clinicians ...
(Date:6/23/2016)... MOUNTAIN VIEW, Calif. , June 23, 2016 ... 9:00 a.m. CST on Thursday, July 7, 2016 , , ... kayla.belcher@frost.com ) , , , , EXPERT PANELISTS:  ... Sciences, Nitin Naik; Senior Industry Analyst, Christi Bird; Senior Industry Analyst, ... The global pharmaceutical industry is witnessing ...
(Date:6/23/2016)... , June 23, 2016 The vast ... an outpatient dialysis facility.  Treatments are usually 3 times ... hours per visit, including travel time, equipment preparation and ... patient, but especially grueling for patients who are elderly ... a skilled nursing and rehabilitation centers for some duration ...
Breaking Medicine Technology: