Featured Research

from universities, journals, and other organizations

HIV makes protein that may help virus's resurgence

Date:
February 25, 2011
Source:
Children's Hospital of Philadelphia
Summary:
New research enhances the current knowledge of how human immunodeficiency virus type-1 (HIV-1), which causes AIDS, controls the cell cycle of cells that it infects. The new findings may shed light on how the virus reactivates after entering a dormant state, called latency. Better understanding of the biological events that revive HIV from latency may eventually lead to better treatments for people with HIV infection.

New research enhances the current knowledge of how human immunodeficiency virus type-1 (HIV-1), which causes AIDS, controls the cell cycle of cells that it infects. The new findings may shed light on how the virus reactivates after entering a dormant state, called latency.

"As we better understand the biological events that revive HIV from latency, we hope to devise ways to eventually intervene in this process with better treatments for people with HIV infection," said study leader Terri H. Finkel, M.D., Ph.D., chief of Rheumatology at The Children's Hospital of Philadelphia.

Finkel is the senior author of a study published in the Jan. 27 issue of the journal Blood. The first author, also from Children's Hospital, is Jiangfang Wang, M.D., Ph.D.

Viral latency is one of the persistent problems in treating HIV infection. Current combinations of anti-HIV drugs can reduce HIV to undetectable levels, but the virus hides in latently infected cells in a sort of hibernation. If a patient stops taking medication, or is weakened by a different infection, HIV can make a resurgence out of its viral reservoirs, often becoming resistant to previously effective drugs.

The current study focused on a protein, Vif (for viral infectivity factor), that HIV-1 produces. Finkel and colleagues previously discovered that Vif causes HIV-infected cells to stop growing at one phase of the cell cycle, the G2 phase. The study team has now found that Vif also acts at an earlier stage in the cell cycle, driving cells out of the G1 phase and into the more active S phase.

This activity may be important, said Finkel, because G1 is a resting phase, and a biological interaction that "wakes up" a latent infected cell may reactivate the infection. Other viruses that have a latent infectious state, such as the herpes virus and the Epstein-Barr virus, also express proteins that drive a transition from G1 to S phase. "By regulating the cell cycle, viruses control their infectivity," said Finkel.

The researchers carried out their work in HeLa cells, a human cell line long used in cell studies, as well as in human T cells, immune cells found in the blood. They identified two proteins, Brd4 and Cdk9, which interact with Vif. This interaction was a new discovery, although the proteins were already known to regulate the progression of the cell cycle.

Identifying Vif's cellular partners may also implicate them as potential targets for therapy. "If we can interrupt the activity of Brd4 or Cdk9, we may be able to prevent latent infection from becoming active," said Finkel. "Alternatively, by harnessing Brd4 or Cdk9, we may be able to drive cells out of latency and make the virus susceptible to anti-HIV drugs." She added that early preclinical testing of inhibitors is getting under way for other conditions, but cautioned that it is too early to foresee whether, or how soon, her research findings will lead to clinical treatments for HIV.

The National Institutes of Health, the Children's Hospital of Philadelphia Research Institute, and the University of Pennsylvania Center for AIDS Research contributed support to this study.


Story Source:

The above story is based on materials provided by Children's Hospital of Philadelphia. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. Wang, E. L. Reuschel, J. M. Shackelford, L. Jeang, D. K. Shivers, J. A. Diehl, X.-F. Yu, T. H. Finkel. HIV-1 Vif promotes the G1- to S-phase cell-cycle transition. Blood, 2010; 117 (4): 1260 DOI: 10.1182/blood-2010-06-289215

Cite This Page:

Children's Hospital of Philadelphia. "HIV makes protein that may help virus's resurgence." ScienceDaily. ScienceDaily, 25 February 2011. <www.sciencedaily.com/releases/2011/02/110225122822.htm>.
Children's Hospital of Philadelphia. (2011, February 25). HIV makes protein that may help virus's resurgence. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/2011/02/110225122822.htm
Children's Hospital of Philadelphia. "HIV makes protein that may help virus's resurgence." ScienceDaily. www.sciencedaily.com/releases/2011/02/110225122822.htm (accessed September 23, 2014).

Share This



More Health & Medicine News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Ebola Doctor Says Border Controls Critical

Ebola Doctor Says Border Controls Critical

AP (Sep. 22, 2014) A Florida doctor who helped fight the expanding Ebola outbreak in West Africa says the disease can be stopped, but only if nations quickly step up their response and make border control a priority. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins