Navigation Links
Tuberculosis: The bacillus takes refuge in adipose cells

A team from the Institut Pasteur has recently shown that the tuberculosis bacillus hides from the immune system in its host's fat cells. This formidable pathogen is protected against even the most powerful antibiotics in these cells, in which it may remain dormant for years. This discovery, published in PLoS ONE, sheds new light on possible strategies for fighting tuberculosis. Attempts to eradicate the bacillus entirely from infected individuals should take these newly identified reservoir cells into account.

Mycobacterium tuberculosis, the bacillus responsible for tuberculosis can hide, in a dormant state, in adipose cells throughout the body. The bacterium is protected in this cellular environment, to which the natural immune defences have little access, and is inaccessible to isoniazid, one of the main antibiotics used to treat tuberculosis worldwide. These results were obtained by Olivier Neyrolles* and his colleagues from the Mycobacterial Genetics Unit directed by Brigitte Gicquel at the Institut Pasteur, in collaboration with Paul Fornès, a pathologist from Hôpital Européen Georges Pompidou. They raise questions of considerable importance in the fight against tuberculosis.

Tuberculosis kills almost two million people worldwide every year and is considered by the World Health Organisation to represent a global health emergency. However, the bacillus is much more prevalent in the world's population than the statistics would lead us to believe, because only 5 to 10% of those infected actually develop tuberculosis. The bacillus may be present in a significant proportion of the population, remaining in a "dormant" state in the body, sometimes for years, and may be "reactivated" at any time. The risk of rea ctivation is particularly high in immunocompromised individuals, such as those infected with AIDS: the HIV virus and the tuberculosis bacillus make a formidable team, with each infectious agent facilitating the progression of the other.

< p>Neyrolles' team first demonstrated, in cell and tissue cultures, that adipose cells served as a reservoir for Mycobacterium tuberculosis, and that this protected the bacillus against isoniazid. They then investigated whether the pathogen was present in adipose cells in humans. They did this by testing for traces of the genetic structure of the bacillus in samples from people considered not to be infected. Analyses were carried out on samples from deceased subjects from Mexico, where tuberculosis is endemic, and from Parisian districts reporting very few cases of tuberculosis.

The bacterium was detected in the adipose tissue of about a quarter of these people, all of whom were unaware they were infected, in both Mexico and France. These results suggest that the bacillus responsible for tuberculosis can remain protected in the adipose tissue of the body in the absence of any sign of disease.

This work has important implications for the prevention of this disease. It helps to explain how, many years after first testing positive for tuberculosis, people with no trace of the microbe in the lungs may develop some form of tuberculosis attacking the lungs, bones or genitals. It also suggests that isoniazid treatment, prescribed to the close friends and family of patients as a preventative measure, may in some cases not provide sufficient protection against the disease. This is particularly important for immunocompromised patients and for people with AIDS, for whom a secondary infection with tuberculosis bacillus may have very serious consequences.

This work highlights the importance of the search for new targeted therapeutic weapons, such as new antibiotics, which must be able to reach the dormant bacillus that has been hiding in adipose cells without our knowing it.


'"/>

Source:Public Library of Science


Related biology news :

1. NJIT Presidential Award winner takes stem cell research another step
2. Unique library of plant genes germinates, takes root at UNC
3. New influenza vaccine takes weeks to mass produce
4. Oops! Researchers publish new findings on the brains response to costly mistakes
5. Blood flow in brain takes a twist, affecting views of Alzheimers
6. HIV vaccine takes different tack to boosting immune response
7. Taking evolutions temperature: Researchers pinpoint the energy it takes to make a species
8. For Stanford scientists, RNAi gene therapy takes two steps forward, one step back
9. Pitt phage hunter takes on tuberculosis
10. The brain, traffic and nano-circuits -- e-Science takes on major challenges
11. Diabetes research takes wing thanks to long-lived fruit fly
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:12/15/2016)... 15, 2016 Advancements in biometrics ... wellness and wellbeing (HWW), and security of ... new passenger vehicles begin to feature fingerprint ... heart beat monitoring, brain wave monitoring, stress ... and pulse detection. These will be driven ...
(Date:12/12/2016)... , Dec. 12, 2016  Researchers at ... possibilities for graphene by combining the material with ... highly sensitive pressure detector able to sense pulse, ... a small spider.  The research ... can be read here:  http://science.sciencemag.org/content/354/6317/1257 ...
(Date:12/7/2016)... PUNE, India , December 7, 2016 According to ... NLP, Machine Learning), Software Tool (Facial Expression, Voice Recognition), Service, Application Area, End ... size is estimated to grow from USD 6.72 Billion in 2016 to USD ... Continue Reading ... ...
Breaking Biology News(10 mins):
(Date:1/21/2017)... ... 2017 , ... G&L Scientific Inc, a leading provider of ... has announced the opening of new offices in Cambridge, Massachusetts, strengthening and improving ... is the latest step in G&L’s expansion of its global clinical consulting services ...
(Date:1/21/2017)... -- Bioptix, Inc. (Nasdaq: BIOP ... 14, 2017 the Board of Directors of the Company ... certain employees associated with the September 2016 acquisition of ... on January 16, 2017 and terminations are expected to ... severance benefits in certain circumstances of up to one ...
(Date:1/20/2017)... Stock-Callers.com explores the Biotech industry ... most recent performances of select equities. In this morning,s ... ), Abeona Therapeutics Inc. (NASDAQ: ABEO ), ... Sage Therapeutics Inc. (NASDAQ: SAGE ). According ... global Biotech market size is expected to reach $604.40 billion by 2020 due ...
(Date:1/19/2017)... 2017 Research and Markets has announced the ... Cancer Type, Application - Global Opportunity Analysis and Industry Forecast, 2014-2022" ... ... market is projected to reach $15,737 million by 2022 from $6,521 ... 2022. Omic technologies segment accounted for more than ...
Breaking Biology Technology: