Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New avenue of HIV damage found

10.10.2002


Researchers at the University of Minnesota have discovered a new process by which HIV damages the immune system. They demonstrated that the portion of lymph nodes called the T cell zone is significantly damaged by chronic inflammation, which causes fibrosis. This is important because the T cell zone is where a significant portion of the human immune response occurs. The finding of accumulation of scar tissue in this portion of the lymph node may explain why aggressive anti-retroviral therapy (ART) does not improve the immune system in some people with HIV-1 infection. The study findings will be published in the Oct. 16, 2002, issue of the Journal of Clinical Investigation. The paper can be found at www.jci.org.



"HIV infection ultimately depletes the body of CD4 T cells, making it impossible to mount an immune response," said Timothy W. Schacker, M.D., associate professor of medicine and author of the study. "For the first time, we show that one mechanism of this depletion is damage to the structure that these cells need to maintain a normal-sized population and to mount an immune response to other infections. In essence, the T cell home is destroyed."

Researchers enrolled 11 individuals at various stages of HIV/AIDS infection. Their goal was to understand the specific changes that happen in the population of cells most directly affected by HIV--the CD4 T cells. These cells are responsible for coordinating the immune response and are the primary target for HIV infection and replication. Researchers biopsied and examined the lymph node tissue before and during treatment for HIV. They have developed sensitive methods to precisely measure both the size of the CD4 population in lymphatic tissue and the amount of scar tissue accumulated in the T cell zone.


Researchers noted two significant findings. First, the size of the CD4 T cell population measured in peripheral blood (commonly done to stage the disease and determine the effects of treatment) does not accurately reflect the size of the population in lymph tissues. "You could have a reasonable peripheral count and a very poor count in lymph tissues," said Schacker.

Second, the amount of fibrosis and scar tissue in the T cell zone was significantly related to the size of the CD4 population in that space (i.e. the more scar tissue, the fewer cells) and the recovery of the CD4 population with therapy. The researchers suggest the process of destruction is analogous to what is seen in chronic active hepatitis.

"We knew that T cells are destroyed by direct viral replication," said Schacker, "but we now know that the population is unable to recover to a normal size because the environmental niche used to support the cells is destroyed. New CD4 T cells are unable to get into the space they need to be in to function, and there is no space for the cells to divide."

One implication of this discovery is that through testing of the lymph nodes (similar to what is done to stage cancer), physicians might accurately stage the disease and predict the response to standard therapies.

"This is essentially a new concept in how HIV infection causes damage to the human immune system," said Schacker. "Our observation may explain why up to 25 percent of people placed on HIV therapy may have good viral suppression but still have no significant increase in T cell count.

"Currently, most treatment strategies for HIV/AIDS focus on stopping the virus from replicating itself in the body, which is essential to begin the process of immune reconstitution, but it does not happen for everyone. These findings suggest that therapies targeting the damage from inflammation and accumulation of scar tissue might enhance current antiviral therapy."

Deane Morrison | EurekAlert!
Further information:
http://www.umn.edu/

More articles from Health and Medicine:

nachricht Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center

nachricht Overdosing on Calcium
19.06.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Creating a new composite fuel for new-generation fast reactors

20.06.2018 | Materials Sciences

Game-changing finding pushes 3D-printing to the molecular limit

20.06.2018 | Materials Sciences

Could this material enable autonomous vehicles to come to market sooner?

20.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>