Navigation Links
How does Mycobacterium tuberculosis infect the lung?

Tuberculosis (TB) is the most common major infectious disease today. It is estimated that two billion people--or one-third of the world's population--are chronically infected without active symptoms. Nine million new cases of active disease are diagnosed annually, resulting in two million deaths. TB is predominantly a lung disease. It is caused by a microbe called Mycobacterium tuberculosis which infects lung cells, but it is still not clear how exactly this happens. Ludovic Tailleux, Olivier Neyrolles, and colleagues (from the Pasteur Institute, in collaboration with the Necker and Saint-Louis Hospitals, in Paris) have found that a molecule called DC-SIGN plays a crucial part.

The researchers wanted to examine whether lung cells from patients with TB were different from those of healthy people or those with different lung diseases, and what that tells us about the way the infection spreads in the lung. In particular, they looked at the surface of the lung cells, because this is the part directly involved in the first contact with the Mycobacterium. As they report now in the international open-access medical journal PLoS Medicine, they studied 74 individuals, 40 of whom had TB, 25 had other inflammatory lung diseases, and 9 had neither active TB nor lung inflammation and served as healthy "controls." The patients underwent a procedure called broncho-alveolar lavage that washes out some of the secretions and cells from the lower respiratory tract. The researchers then analyzed the cells in different ways. They concentrated on a type of cell called a macrophage (the natural target of Mycobacterium) and found that macrophages from patients with TB had much more the DC-SIGN protein on their surface than macrophages from patients with other diseases or from the control individuals.

They then took macrophages from a control individual (which had very low levels of DC-SIGN) and infected them with Mycobaterium under laboratory conditions. They found that s hortly after infection not only the infected cells but also some of their neighbours started to display DC-SIGN on their surface. They also found that having DC-SIGN on the surface made uninfected cells much more susceptible to infection.

These results suggest that DC-SIGN has an important function in amplifying TB infection in the lung. Interfering with DC-SIGN function might therefore be a new way to fight TB, a disease that is becoming increasingly resistant to existing therapies and for which new drugs are urgently needed.


'"/>

Source:Public Library of Science


Related biology news :

1. Scientists find missing enzyme for tuberculosis iron scavenging pathway
2. New vaccine protects more effectively against tuberculosis
3. Scientists discover gene that controls speed of tuberculosis development
4. Once-dreaded leprosy replaced by tuberculosis, say researchers
5. Gene increases risk of tuberculosis
6. Experimental TB drug effective against resistant and latent mycobacterium tuberculosis
7. New potential drug target in tuberculosis
8. Pitt phage hunter takes on tuberculosis
9. World-wide warning of highly drug-resistant tuberculosis
10. Faster, more accurate tuberculosis test developed
11. New research may overturn conventional wisdom on drug-resistant tuberculosis
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/18/2017)... April 18, 2017  Socionext Inc., a global expert in SoC-based ... edge server, the M820, which features the company,s hybrid codec technology. ... by Tera Probe, Inc., will be showcased during the upcoming Medtec ... show at the Las Vegas Convention Center ... Click here ...
(Date:4/11/2017)... Apr. 11, 2017 Research and Markets has ... report to their offering. ... The global eye tracking market to grow at a CAGR of ... Eye Tracking Market 2017-2021, has been prepared based on an in-depth ... market landscape and its growth prospects over the coming years. The ...
(Date:4/5/2017)... April 5, 2017 Today HYPR Corp. ... the server component of the HYPR platform is officially ... the end-to-end security architecture that empowers biometric authentication across ... has already secured over 15 million users across the ... of connected home product suites and physical access represent ...
Breaking Biology News(10 mins):
(Date:5/23/2017)... ... May 23, 2017 , ... ... for research and the development of cardiac regeneration therapies. The development of ... of cardiomyocytes (hPSC-CMs). Due to varying differentiation efficiencies, further enrichment of CM ...
(Date:5/23/2017)... MENLO PARK, CA (PRWEB) , ... May 23, 2017 , ... ... announced the publication of “Label-free isolation of prostate circulating tumor cells using Vortex ... publication is the result of a collaboration with Dr. Dino Di Carlo and Dr. ...
(Date:5/23/2017)... ... May 23, 2017 , ... Cambridge Semantics , ... at this year’s Bio-IT World Conference and Expo in Boston May 23-25 ... 4.0 solution. The Anzo Smart Data Lake is also a finalist for the ...
(Date:5/22/2017)... ... May 22, 2017 , ... Cancer diagnostics ... in booth B2 at the Association for Pathology Informatics Annual Summit ... addition to demonstrating its Cancer Diagnostic Cockpit and Consultation Portal, Inspirata will present ...
Breaking Biology Technology: