Featured Research

from universities, journals, and other organizations

Degradation of viral DNA in cell nucleus opening up new treatment for hepatitis B

Date:
February 21, 2014
Source:
Helmholtz Zentrum München - German Research Center for Environmental Health
Summary:
Viruses such as HBV can persist by depositing their genetic information (DNA) in the cell nucleus, where the DNA is normally not degraded. This prevents antiviral drugs from eliminating these viruses. But a newly discovered mechanism could make this possible without damaging the infected cell in the liver, possibly opening up new therapeutic possibilities.

Viruses such as HBV can persist by depositing their genetic information (DNA) in the cell nucleus, where the DNA is normally not degraded. This prevents antiviral drugs from eliminating these viruses. But the newly discovered mechanism could make this possible without damaging the infected cell in the liver. In the current issue of the journal Science, the scientists report that now new therapeutic possibilities are consequently opening up.

Although preventive vaccination is possible, the World Health Organization (WHO) reports that more than 240 million people around the world are currently suffering from a chronic hepatitis B infection. They face a high risk of developing liver cirrhosis or even liver cancer. In Germany alone, more than half a million people are affected. Although available antiviral medicines can control the hepatitis B virus, they cannot completely eliminate it. As a result, the HBV in the patient's liver is reactivated as soon as the treatment is discontinued.

This is due to virus DNA (cccDNA: covalently closed circular DNA) "hidden" in the cell nucleus. This virus DNA stores multiple copies of the virus in the nucleus of infected liver cells (hepatocytes) and in this way protects itself from destructive influences. The cccDNA serves as a template for the virus' own proteins and new viral genomes. An international team of scientists headed by Prof. Ulrike Protzer and Prof. Mathias Heikenwälder, Institute of Virology at the Helmholtz Zentrum München and the Technische Universität München, has now found a way to selectively attack and eliminate the viral genetic information in the cell nucleus of the liver cells without damaging the host cell in the process.

"The degradation of viral DNA in the cell nucleus that we describe represents an important mechanism in the defense against the virus," Protzer reports. "Moreover, for the first time, the results offer the possibility to develop a treatment that can heal hepatitis B."

The scientists have discovered that in addition to interferons (the immune system's defense agents), activation of the lymphotoxin β receptor in the host cell promotes certain proteins and supports their function in such a way that they chemically modulate and degrade viral cccDNA. This keeps the virus from reactivating, and also prevents the disease from breaking out again, even after the treatment has ended.

On the other hand, the proteins do not influence the genetic information of the host cell itself, which here is the liver cell. "With the activation of the lymphotoxin β receptor, also combined with substances that are already available, we have a very promising new therapy concept available," Heikenwälder explains.


Story Source:

The above story is based on materials provided by Helmholtz Zentrum München - German Research Center for Environmental Health. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. Lucifora, Y. Xia, F. Reisinger, K. Zhang, D. Stadler, X. Cheng, M. F. Sprinzl, H. Koppensteiner, Z. Makowska, T. Volz, C. Remouchamps, W.-M. Chou, W. E. Thasler, N. Huser, D. Durantel, T. J. Liang, C. Munk, M. H. Heim, J. L. Browning, E. Dejardin, M. Dandri, M. Schindler, M. Heikenwalder, U. Protzer. Specific and Nonhepatotoxic Degradation of Nuclear Hepatitis B Virus cccDNA. Science, 2014; DOI: 10.1126/science.1243462

Cite This Page:

Helmholtz Zentrum München - German Research Center for Environmental Health. "Degradation of viral DNA in cell nucleus opening up new treatment for hepatitis B." ScienceDaily. ScienceDaily, 21 February 2014. <www.sciencedaily.com/releases/2014/02/140221103926.htm>.
Helmholtz Zentrum München - German Research Center for Environmental Health. (2014, February 21). Degradation of viral DNA in cell nucleus opening up new treatment for hepatitis B. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2014/02/140221103926.htm
Helmholtz Zentrum München - German Research Center for Environmental Health. "Degradation of viral DNA in cell nucleus opening up new treatment for hepatitis B." ScienceDaily. www.sciencedaily.com/releases/2014/02/140221103926.htm (accessed July 29, 2014).

Share This




More Health & Medicine News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) — West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
$15B Deal on Vets' Health Care Reached

$15B Deal on Vets' Health Care Reached

AP (July 28, 2014) — A bipartisan deal to improve veterans health care would authorize at least $15 billion in emergency spending to fix a veterans program scandalized by long patient wait times and falsified records. (July 28) Video provided by AP
Powered by NewsLook.com
Two Americans Contract Ebola in Liberia

Two Americans Contract Ebola in Liberia

Reuters - US Online Video (July 28, 2014) — Two American aid workers in Liberia test positive for Ebola while working to combat the deadliest outbreak of the virus ever. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) — Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) 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:
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