Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCLA scientists uncork fountain of youth for HIV-fighting cells

15.11.2004


Protein may help immune system fend off virus



UCLA scientists have shown that a protein called telomerase prevents the premature aging of the immune cells that fight HIV, enabling the cells to divide indefinitely and prolong their defense against infection. Published Nov. 15 in the Journal of Immunology, the research suggests a future therapy for boosting the weakened immune systems of HIV-positive people.

Every cell contains a tiny cellular clock called a telomere, which shortens each time the cell splits in two. Located at the end of the cell’s chromosome, the telomere limits the number of times a cell can divide. "Immune cells that fight HIV are under constant strain to divide in order to continue performing their protective functions. This massive amount of division shortens these cells’ telomeres prematurely," explained Dr. Rita Effros, Plott Chair in Gerontology and professor of pathology and laboratory medicine at the David Geffen School of Medicine at UCLA. "So the telomeres of a 40-year-old person infected with HIV resemble those of a healthy 90-year-old person."


Most scientists agree that telomeres evolved to avert the rampant cell growth that often leads to cancer. Yet many cancers continue growing because they undergo genetic changes and start to produce telomerase, which regenerates their cells’ telomeres.

Effros and first author Mirabelle Dagarag, Ph.D., hypothesized that harnessing telomerase’s power over telomeres may provide a potent weapon in helping the AIDS patient’s exhausted immune system defend itself against HIV. The researchers extracted immune cells from the blood of HIV-infected persons and tested what would happen if telomerase remained permanently switched on in the cell. "By exploiting telomerase’s growth influence on telomeres, we thought we might be able to keep the immune cells youthful and active as they replicated under attack," said Dagarag, a postgraduate researcher. "We used gene therapy to boost the immune cell’s telomerase and then exposed the cell to HIV."

What Dagarag and Effros saw delighted them.

"We found that the immune cells could divide endlessly," said Effros, a member of the UCLA AIDS Institute. "They grew at a normal rate and didn’t show any chromosomal abnormalities that might lead to cancer." "We also saw that telomerase stabilized the telomere length," added Dagarag. "The telomere didn’t shorten each time the cell divided, which left the cell able to vigorously battle HIV much longer."

The UCLA work is the first to prove that maintaining telomerase activity in immune cells from HIV-infected persons prevents telomeres from shortening. "This is the first step toward developing other telomerase-based strategies for controlling HIV disease," said Dagarag. "Increasing the amount of telomerase in certain immune cells may one day hold the key to treating AIDS." "To battle HIV infection effectively, we must strengthen the human immune system -- not just suppress the virus as current drugs do," said Effros. "We need a two-pronged approach to attack the disease from both sides of the medical equation."

Effros and the Geron Corporation, which collaborated on this study, are also testing several non-genetic methods of activating telomerase as potential treatments for persons infected with HIV.

The UCLA team’s approach could provide the foundation for immunotherapy as a treatment for HIV and related diseases that rely on lasting protection by the same immune cells. These include cancer and latent cytomegalovirus, a viral infection that often strikes organ-transplant patients and persons with AIDS.

Elaine Schmidt | EurekAlert!
Further information:
http://www.ucla.edu

More articles from Life Sciences:

nachricht Rochester scientists discover gene controlling genetic recombination rates
23.04.2018 | University of Rochester

nachricht One step closer to reality
20.04.2018 | Max-Planck-Institut für Entwicklungsbiologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
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

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Structured light and nanomaterials open new ways to tailor light at the nanoscale

23.04.2018 | Physics and Astronomy

On the shape of the 'petal' for the dissipation curve

23.04.2018 | Physics and Astronomy

Clean and Efficient – Fraunhofer ISE Presents Hydrogen Technologies at the HANNOVER MESSE 2018

23.04.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>