Featured Research

from universities, journals, and other organizations

Scavenger cells accomplices to viruses

Date:
July 25, 2011
Source:
University of Zurich
Summary:
Mucosal epithelia are well-protected against pathogenic germs. However, individual viruses, such as the HI virus, still manage to enter the body via the mucous membrane somehow. Cell biologists have now identified a new infection mechanism, demonstrating that the viruses use the body’s own scavenger cells for the infection. The new findings are important for cancer-gene therapy and the development of anti-viral medication.

Adenoviruses en route to infection: Red-colored adenovirus particles are found in the periphery of a human epithelial cell and steadily move towards the cell nucleus at the bottom of the image. The endocytic vesicles in the cell are colored green. Most of the viruses do not move together with these endosomes, but rather towards the nucleus with other molecules of the cell which are not shown here.
Credit: Adenoviruses (picture: Michele Gastaldelli, Universität Zürich, Institut für Molekulare Biologie)

Mucosal epithelia are well-protected against pathogenic germs. However, individual viruses, such as the HI virus, still manage to enter the body via the mucous membrane somehow. Cell biologists from the University of Zurich have now identified a new infection mechanism, demonstrating that the viruses use the body's own scavenger cells for the infection. The new findings are important for cancer-gene therapy and the development of anti-viral medication.

Mucosal epithelia do not have any receptors on the outer membrane for the absorption of viruses like hepatitis C, herpes, the adenovirus or polio, and are thus well-protected against pathogenic germs. However, certain viruses, such as the human immunodeficiency virus HIV, still manage to enter the body via the mucous membrane. Just how this infiltration occurs on a molecular level has been a mystery. Three hypotheses were discussed: firstly, that it's caused by mechanical damage to the mucous membrane; secondly, the presence of previously unknown receptors on the mucous membrane cells; and, thirdly, that the viruses are smuggled in via a kind of Trojan horse. Now, for the first time, cell biologists from the University of Zurich have succeeded in identifying the infection mechanism for adenoviruses.

In the recently published online magazine Nature Communications, Verena Lütschg and cell biologists from the Institute of Molecular Biology headed by Urs Greber reveal how type-5 adenoviruses in the lung epithelia utilize an immune response triggered by the infection for the progression of the infection: Adenoviruses use scavenger cells and their subsequent production of antiviral cytokines as a door-opener for the infection of the lung epithelial cells.

Exposure of shielded receptors

Antiviral cytokines play a key role in immunological reactions and trigger inflammatory responses, for instance. They induce the epithelial cells to expose certain receptors that are shielded under normal conditions and thus activate immune cells in defense. For healthy people, an infection of the lung with type-5 adenoviruses is harmless as they merely cause a cold. Under very stressful situations or in the case of chronic respiratory diseases, however, adenoviruses can cause severe, acute infections that can sometimes be fatal.

The recently identified infection mechanism can serve as a model for how the pathogens penetrate the mucosal epithelial cells and enter the body. However, it is also crucial from a therapeutic point of view. Type-5 adenoviruses are already used very often as transport vehicles in cancer-gene therapy today. Knowing the transport route will help develop both this gene therapy and specifically acting cancer treatment further.


Story Source:

The above story is based on materials provided by University of Zurich. Note: Materials may be edited for content and length.


Journal Reference:

  1. Verena Lütschg, Karin Boucke, Silvio Hemmi, Urs F. Greber. Chemotactic antiviral cytokines promote infectious apical entry of human adenovirus into polarized epithelial cells. Nature Communications, 2011; 2: 391 DOI: 10.1038/ncomms1391

Cite This Page:

University of Zurich. "Scavenger cells accomplices to viruses." ScienceDaily. ScienceDaily, 25 July 2011. <www.sciencedaily.com/releases/2011/07/110721102026.htm>.
University of Zurich. (2011, July 25). Scavenger cells accomplices to viruses. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2011/07/110721102026.htm
University of Zurich. "Scavenger cells accomplices to viruses." ScienceDaily. www.sciencedaily.com/releases/2011/07/110721102026.htm (accessed August 21, 2014).

Share This




More Health & Medicine News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) — An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Cadavers, a Teen, and a Medical School Dream

Cadavers, a Teen, and a Medical School Dream

AP (Aug. 21, 2014) — Contains graphic content. He's only 17. But Johntrell Bowles has wanted to be a doctor from a young age, despite the odds against him. He was recently the youngest participant in a cadaver program at the Indiana University NW medical school. (Aug. 21) Video provided by AP
Powered by NewsLook.com
American Ebola Patients Released: What Cured Them?

American Ebola Patients Released: What Cured Them?

Newsy (Aug. 21, 2014) — It's unclear whether the American Ebola patients' recoveries can be attributed to an experimental drug or early detection and good medical care. Video provided by Newsy
Powered by NewsLook.com
Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) — According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
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:
from the past week

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