HOME >> BIOLOGY >> NEWS
Food safety: French discovery explains how Listeria penetrates the body, and may suggest new drug delivery strategies

e to enter the bloodstream, where it disseminates to the central nervous system and the placenta. But, the molecular events that allow Listeria to cross the intestinal barrier have remained a mystery--until now.

In previous studies, Cossart and her colleagues--including Jean Louis Gaillard, Jerme Mengaud and Marc Lecuit--had shown that a protein on Listeria's surface called "internalin" interacts with a receptor, E-cadherin found on cultured cells derived from the intestine. Similar to a key-and-lock system, internalin interacts with E-cadherin to promote the entry of Listeria into intestinal cells. Listeria can then cross the intestine and pass into the bloodstream, scientists said.

Studying this mechanism in animals proved difficult, however, because rats and mice produce a form of cadherin that doesn't bind with internalin. Fortunately, guinea pigs generate a suitable version of the protein, making these animals a useful model for studying oral Listeria infection. The difference between the two forms of cadherin, Cossart explained, is a single amino acid in the 16th position of cadherin's molecular chain.

For their latest Science study, Lecuit et al.(Cossart's team in collaboration with transgenesis expert Charles Babinet and other scientists at the Pasteur Institute), investigated oral infection mechanisms within guinea pigs and transgenic mice, which had been genetically modified to express the human version of cadherin in the intestine. Animals received oral doses of both wild-type Listeria, as well as a mutant, internalin-free version of the bacterium. Wild Listeria, featuring the internalin protein, proved fatal in most cases, whereas the mutant strain caused no deaths and failed to cross the intestine and invade organ tissues.

Thus, the French investigation identifies a "virulence factor" or molecular mechanism by which Listeria causes disease, thereby addressing a key recommenda
'"/>

Contact: Ginger Pinholster
gpinhols@aaas.org
202-326-6421
American Association for the Advancement of Science
31-May-2001


Page: 1 2 3 4

Related biology news :

1. Bones from French cave show Neanderthals, Cro-Magnon hunted same prey
2. Fire on French Riviera
3. Smaller food portions may explain the French paradox of rich foods and a svelte population
4. ESA providing Kyoto estimates of French Guianas tropical forests
5. Researchers develop white wine with cholesterol-lowering benefits, discover Israeli wines healthier than French wines
6. Beyond the French paradox
7. Study seems to show why French suffer less heart disease, cancer
8. The Reason The French Have Low Levels Of Heart Disease
9. New Technology Turns French Fry Oil Into Diesel Fuel
10. French Researchers Breed Flightless Ladybirds As Pest-Killers
11. Very Fruitful Collaboration Between French And German Scientists Yields Unusual Insights Into The Structure Of Membrane Proteins

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/24/2017)... March 24, 2017 The Controller General of Immigration ... Abdulla Algeen have received the prestigious international IAIR Award for ... Continue Reading ... ... Deputy Controller Abdulla Algeen (small picture on the right) have received the ...
(Date:3/22/2017)...   Neurotechnology , a provider of high-precision ... the release of the SentiVeillance 6.0 ... recognition using up to 10 surveillance, security and ... new version uses deep neural-network-based facial detection and ... a Graphing Processing Unit (GPU) for enhanced speed. ...
(Date:3/20/2017)... March 20, 2017 PMD Healthcare announces the ... and Wellness Management System (WMS), a remote, real-time lung ... 2010, PMD Healthcare is a Medical Device, Digital Health, ... dedicated to creating innovative solutions that empower people to ... intent focus, PMD developed the first ever personal spirometer, ...
Breaking Biology News(10 mins):
(Date:3/27/2017)... ROCKVILLE, Md. , March 27, 2017 /PRNewswire/ ... $108.5 billion for 2016, according to a new ... patients, medical lab testing is performed to evaluate ... determine individual therapy, among other reasons.  The healthcare ... Services Market , provides an overview of ...
(Date:3/27/2017)... 2017 The new research portal will ... of reports on Valero Energy , offering extensive market ... industries. ...      (Logo: http://photos.prnewswire.com/prnh/20160330/349511LOGO) The latest trend ... green. Ethanol today, even though touted as a green alternative ...
(Date:3/27/2017)... ... March 27, 2017 , ... A research team ... vascular grafts in JoVE’s Video Journal, the world’s first peer-reviewed scientific video journal. ... of treating coronary artery disease (CAD). Lam is an assistant professor at the ...
(Date:3/27/2017)... CAESAREA, Israel , March 27, 2017 ... company with mobile health and big data solutions, today ... party insurance coverage option for U.S. consumers who ... DarioHealth has signed strategic alliance agreements ... to verify insurance coverage benefits, and if approved, will ...
Breaking Biology Technology:
Cached News: