Featured Research

from universities, journals, and other organizations

Certain heavy metals boost immunity, study suggests

Date:
September 20, 2011
Source:
CNRS (Délégation Paris Michel-Ange)
Summary:
A new natural defense mechanism against infections has been demonstrated. Zinc, a heavy metal that is toxic at high doses, is used by the cells of the immune system to destroy microbes such as the tuberculosis bacillus or E. coli. This discovery makes it possible to envisage new therapeutic strategies and test new vaccine candidates.

This figure shows a tuberculosis bacillus (M. tuberculosis) in a macrophage. The compartment in which the bacillus resides (a vacuole known as a phagosome) is rich in zinc, which can be seen in the form of small black deposits (zinc sulfate) by electron microscopy after specific treatment.
Credit: © Chantal de Chastellier

A new natural defense mechanism against infections has been evidenced by an international team led by researchers from CNRS, Inserm, the Institut Pasteur and the Université Paul Sabatier -- Toulouse III[1]. Zinc, a heavy metal that is toxic at high doses, is used by the cells of the immune system to destroy microbes such as the tuberculosis bacillus or E. coli.

Related Articles


Published in the journal Cell Host & Microbe on 14 September 2011, this discovery makes it possible to envisage new therapeutic strategies and test new vaccine candidates.

One of the well-known strategies employed by our immune system to destroy microbes consists in depriving them of essential nutrients such as heavy metals, particularly iron. For the first time, an international study headed by researchers from the Institut de Pharmacologie et de Biologie Structurale (CNRS/Université Paul Sabatier -- Toulouse III), the Centre d'Immunologie de Marseille Luminy (CNRS/Inserm/Université de la Méditerranée) and the Institut Pasteur has shown that the reverse is also true: the immune cells are capable of mobilizing reserves of heavy metals, especially zinc, to poison microbes.

This phenomenon has been demonstrated for Mycobacterium tuberculosis, the agent responsible for tuberculosis in humans, which accounts for nearly 2 million deaths worldwide each year, and for Escherichia coli, of which certain strains can cause serious infections of the digestive and urinary systems. In immune system cells (macrophages) that have ingested M. tuberculosis or E. coli, the researchers observed a rapid and persistent accumulation of zinc.

They also observed the production, on the surface of the microbes, of numerous proteins whose role is to "pump out," in other words eliminate, heavy metals. In macrophages, the microbes are thus exposed to potentially toxic quantities of zinc and they try to protect themselves against intoxication by synthesizing these pumps. Inhibiting the pumps through genetic engineering provides proof of evidence: M. tuberculosis and E. coli become even more sensitive to destruction by macrophages.

Zinc, although toxic when ingested in too high quantities, is therefore beneficial for the immune system, particularly because it is used by macrophages to poison microbes. Equivalent mechanisms could exist for other heavy metals such as copper. These results have very concrete clinical implications. In particular, they re-open the debate on dietary supplementation (e.g. with zinc) and they may also lead to new antibiotics that would block the action of microbial pumps on metals or to new attenuated vaccine strains, which have already been tested as vaccine candidates.


Story Source:

The above story is based on materials provided by CNRS (Délégation Paris Michel-Ange). Note: Materials may be edited for content and length.


Journal Reference:

  1. Hélène Botella, Pascale Peyron, Florence Levillain, Renaud Poincloux, Yannick Poquet, Irène Brandli, Chuan Wang, Ludovic Tailleux, Sylvain Tilleul, Guillaume M. Charrière, Simon J. Waddell, Maria Foti, Geanncarlo Lugo-Villarino, Qian Gao, Isabelle Maridonneau-Parini, Philip D. Butcher, Paola Ricciardi Castagnoli, Brigitte Gicquel, Chantal de Chastellier, Olivier Neyrolles. Mycobacterial P1-Type ATPases Mediate Resistance to Zinc Poisoning in Human Macrophages. Cell Host & Microbe, 2011; 10 (3): 248 DOI: 10.1016/j.chom.2011.08.006

Cite This Page:

CNRS (Délégation Paris Michel-Ange). "Certain heavy metals boost immunity, study suggests." ScienceDaily. ScienceDaily, 20 September 2011. <www.sciencedaily.com/releases/2011/09/110920080143.htm>.
CNRS (Délégation Paris Michel-Ange). (2011, September 20). Certain heavy metals boost immunity, study suggests. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2011/09/110920080143.htm
CNRS (Délégation Paris Michel-Ange). "Certain heavy metals boost immunity, study suggests." ScienceDaily. www.sciencedaily.com/releases/2011/09/110920080143.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) — Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
Today's Prostheses Are More Capable Than Ever

Today's Prostheses Are More Capable Than Ever

Newsy (Nov. 26, 2014) — Advances in prosthetics are making replacement body parts stronger and more lifelike than they’ve ever been. Video provided by Newsy
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) — The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) — Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 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:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

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