Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

HIV makes protein that may help virus's resurgence

28.02.2011
Children's Hospital of Philadelphia study sheds light on how HIV takes over cell cycle

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.

"HIV-1 Vif promotes the G1-to S-phase cell-cycle transition," Blood, Jan. 27, 2011. doi: 10.1182/blood-2010-06-289215

About The Children's Hospital of Philadelphia: The Children's Hospital of Philadelphia was founded in 1855 as the nation's first pediatric hospital. Through its long-standing commitment to providing exceptional patient care, training new generations of pediatric healthcare professionals and pioneering major research initiatives, Children's Hospital has fostered many discoveries that have benefited children worldwide. Its pediatric research program is among the largest in the country, ranking third in National Institutes of Health funding. In addition, its unique family-centered care and public service programs have brought the 460-bed hospital recognition as a leading advocate for children and adolescents. For more information, visit http://www.chop.edu.

John Ascenzi | EurekAlert!
Further information:
http://www.chop.edu

Further reports about: Aids HIV HIV infection HIV-1 anti-HIV drug blood flow cell cycle health services immune cell

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

Devils Hole: Ancient Traces of Climate History

24.05.2017 | Earth Sciences

Discovery of a Key Regulatory Gene in Cardiac Valve Formation

24.05.2017 | Life Sciences

A CLOUD of possibilities: Finding new therapies by combining drugs

24.05.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>