Featured Research

from universities, journals, and other organizations

Immune evasion common in many viruses, bacteria and parasites is uncommon in M. tuberculosis

Date:
May 24, 2010
Source:
NYU Langone Medical Center / New York University School of Medicine
Summary:
Scientists have discovered that the strategy of "immune evasion" common to many viruses, bacteria and parasites, is uncommon to M. tuberculosis where the antigens remain strikingly unchanged and homogeneous. The study suggests that M. tuberculosis antigens do not mutate because they hope to be recognized by the body's immune system -- perhaps because the host immune mechanism that leads to the typical lung destruction and cough can contribute to the spread of the disease. This finding has the potential to change the direction of vaccine research and could result in a new focus on different targets of immune response to the bacteria.

Scientists at NYU Langone Medical Center have discovered that the strategy of "immune evasion" common to many viruses, bacteria and parasites, is uncommon to M. tuberculosis where the antigens remain strikingly unchanged and homogenous.

The study published in Nature Genetics on May 23, 2010, suggests that M. tuberculosis antigens do not mutate because they hope to be recognized by the body's immune system -- perhaps because the host immune mechanism that leads to the typical lung destruction and cough can contribute to the spread of the disease. This finding has the potential to change the direction of vaccine research and could result in a new focus on different targets of immune response to the bacteria.

"The finding that the tuberculosis bacterium acts completely differently from other pathogens is quite surprising and unexpected," said Joel Ernst, MD, director of the division of Infectious Diseases and Immunology at NYU Langone Medical Center in NYC and lead author of the study. "If you get infected with the influenza virus, for example, the body's immune system recognizes it and tends to eliminate it. In tuberculosis, our immune response doesn't get rid of it -- it tends to hold on to it for a while -- keeping the bacteria under partial control."

The immune system plays a key role in protecting the human body from invading pathogens. These pathogens have molecules known as antigens that are recognized by the immune system. However, many pathogens can evade immune recognition by varying their antigens. This study found that rather than "suffering" from being recognized, recognition of tuberculosis antigens actually benefit the bacteria -- and it is this recognition that helps the bacteria to be transmitted from person to person.

Tuberculosis is a major cause of death and disability worldwide, killing someone every 15 minutes. TB in New York City, and in the United States as a whole, is being driven by the global TB epidemic. In 2008, despite very aggressive and expensive public health efforts, there were 895 cases of TB and 11 cases of multidrug-resistant TB. Over 70 percent of all cases of TB in NYC in 2008 were among individuals born outside the United States, although people with TB can transmit the infection to anyone.

Tuberculosis is a major cause of death and disability worldwide, killing someone every 15 minutes. TB in New York City, and in the United States as a whole, is being driven by the global TB epidemic. In 2008, there were 895 cases of TB and 11 cases of multidrug-resistant TB. Over 70 percent of all cases of TB in NYC in 2008 were among individuals born outside the United States.

Of all the people who get the disease, 90 percent remain well while the immune system suppresses the disease. Approximately 10 percent of the people who get infected then transmit the disease. As a consequence of the emergence of drug resistance, the global epidemic of tuberculosis is worsening. Thus, new tools and strategies are urgently needed to combat this growing epidemic.

For this study, scientists used a novel high-throughput DNA sequencing method to analyze the whole genomes of 22 clinical strains of M. tuberculosis from different parts of the world. They then determined that the number of and type of mutations that occurred in antigens is much lower compared to other regions of the M. tuberculosis genome.

Co-authors of this study include Inaki Comas and Sebastien Gangeux of the Medical Research Council at the National Institute for Medical Research in London and Jaidip Chakravartti of NYU Langone Medical Center.

The study was funded by the National Institutes of Health in Bethesda, Maryland.


Story Source:

The above story is based on materials provided by NYU Langone Medical Center / New York University School of Medicine. Note: Materials may be edited for content and length.


Journal Reference:

  1. Iñaki Comas, Jaidip Chakravartti, Peter M Small, James Galagan, Stefan Niemann, Kristin Kremer, Joel D Ernst & Sebastien Gagneux. Human T cell epitopes of Mycobacterium tuberculosis are evolutionarily hyperconserved. Nature Genetics, 2010; DOI: 10.1038/ng.590

Cite This Page:

NYU Langone Medical Center / New York University School of Medicine. "Immune evasion common in many viruses, bacteria and parasites is uncommon in M. tuberculosis." ScienceDaily. ScienceDaily, 24 May 2010. <www.sciencedaily.com/releases/2010/05/100523205818.htm>.
NYU Langone Medical Center / New York University School of Medicine. (2010, May 24). Immune evasion common in many viruses, bacteria and parasites is uncommon in M. tuberculosis. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2010/05/100523205818.htm
NYU Langone Medical Center / New York University School of Medicine. "Immune evasion common in many viruses, bacteria and parasites is uncommon in M. tuberculosis." ScienceDaily. www.sciencedaily.com/releases/2010/05/100523205818.htm (accessed April 16, 2014).

Share This



More Health & Medicine News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) — A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com
Ebola Outbreak Now Linked To 121 Deaths

Ebola Outbreak Now Linked To 121 Deaths

Newsy (Apr. 15, 2014) — The ebola virus outbreak in West Africa is now linked to 121 deaths. Health officials fear the virus will continue to spread in urban areas. Video provided by Newsy
Powered by NewsLook.com
Cognitive Function: Is It All Downhill From Age 24?

Cognitive Function: Is It All Downhill From Age 24?

Newsy (Apr. 15, 2014) — A new study out of Canada says cognitive motor performance begins deteriorating around age 24. Video provided by Newsy
Powered by NewsLook.com
How Mt. Everest Helped Scientists Research Diabetes

How Mt. Everest Helped Scientists Research Diabetes

Newsy (Apr. 15, 2014) — British researchers were able to use Mount Everest's low altitudes to study insulin resistance. They hope to find ways to treat diabetes. 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