Featured Research

from universities, journals, and other organizations

Acute Hepatitis A evades immune system more effectively than chronic cousin

Date:
June 20, 2011
Source:
University of North Carolina School of Medicine
Summary:
Researchers thought that Hepatitis C might become chronic by disrupting the host's interferon response -- part of the innate immune system that protects the body against any kind of "foreign" invader. However, in comparing data from experiments with Hepatitis A and Hepatitis C, scientists found that Hepatitis A virus, which causes only acute, self-limited disease, is more efficient at inhibiting the host's interferon response, and that the virus can actually linger in the body for almost a year.

Ongoing research into the problem of how Hepatitis C becomes a chronic disease has uncovered a deeper mystery about its sister strain, Hepatitis A.

Hepatitis C is a continuing public health problem, which is difficult to measure because symptoms occur months to years after infection. The World Health Organization estimates as many as 2 to 4 million people in the United States may have chronic Hepatitis C, and most do not know they are infected. More than a third of those who are long-term carriers may develop chronic liver disease or liver cancer.

"Hepatitis viruses have co-evolved with humans over a very long period of time and they are good at evading the immune system, but nobody understands how Hepatitis C becomes a chronic infection," says Stanley M. Lemon, MD, professor of microbiology and immunology and a member of UNC Lineberger Comprehensive Cancer Center and the Center for Translational Immunology.

Lemon and his colleagues thought that Hepatitis C might become chronic by disrupting the host's interferon response -- part of the innate immune system that protects the body against any kind of 'foreign' invader.

However, their study, published on-line in the Early Edition of the journal Proceedings of the National Academy of Sciences U.S.A., came up with some surprising findings.

In comparing data from experiments with Hepatitis A and Hepatitis C, the team found that Hepatitis A virus, which causes only acute, self-limited disease, is more efficient at inhibiting the host's interferon response, and that the virus can actually linger in the body for almost a year.

"These results undermine the theory that evasion of the interferon response is a key mechanism in the development of chronic Hepatitis C -- the outcome of infection with these viruses is very different, highlighting how little we understand the unique environment within the liver for virus-host interactions," Lemon notes.

"It is actually the acute infection, Hepatitis A, that is stealthier at evading the interferon response."

In addition to Lemon, the research team included Zongdi Feng, Ph.D., and Daisuke Yamane, D.V.M, Ph.D. from UNC-Chapel Hill; Robert Lanford, PhD, of the Texas Biomedical Research Institute and the Southwest National Primate Research Center; Deborah Chavez, MS, and Bernadette Guerra, BS, from the Texas Biomedical Research Institute; Kathleen Brasky, DVM, of the Southwest National Primate Center; Yan Zhou, PhD, and Christopher Walker, PhD, of the Center for Vaccines and Immunity at Nationwide Children's Hospital in Columbus, OH; and Alan Perelson, PhD, from Los Alamos National Laboratory.

The research was funded by the National Institutes of Health.


Story Source:

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


Journal Reference:

  1. Robert E. Lanford, Zongdi Feng, Deborah Chavez, Bernadette Guerra, Kathleen M. Brasky, Yan Zhou, Daisuke Yamane, Alan S. Perelson, Christopher M. Walker, and Stanley M. Lemon. Acute hepatitis A virus infection is associated with a limited type I interferon response and persistence of intrahepatic viral RNA. PNAS, June 20, 2011 DOI: 10.1073/pnas.1101939108

Cite This Page:

University of North Carolina School of Medicine. "Acute Hepatitis A evades immune system more effectively than chronic cousin." ScienceDaily. ScienceDaily, 20 June 2011. <www.sciencedaily.com/releases/2011/06/110620161155.htm>.
University of North Carolina School of Medicine. (2011, June 20). Acute Hepatitis A evades immune system more effectively than chronic cousin. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2011/06/110620161155.htm
University of North Carolina School of Medicine. "Acute Hepatitis A evades immune system more effectively than chronic cousin." ScienceDaily. www.sciencedaily.com/releases/2011/06/110620161155.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. 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