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:5/23/2017)... 2017  Hunova, the first robotic gym for the rehabilitation and functional ... in Genoa, Italy . The first 30 robots will ... USA . The technology was developed and patented at ... IIT spin-off Movendo Technology thanks to a 10 million euro investment from ... click: ...
(Date:4/24/2017)... , April 24, 2017 ... and partner with  Identity Strategy Partners, LLP (IdSP) ... "With or without President Trump,s March 6, 2017 ... Terrorist Entry , refugee vetting can be instilled with ... resettlement. (Right now, all refugee applications are suspended ...
(Date:4/13/2017)... 13, 2017 UBM,s Advanced Design and Manufacturing ... feature emerging and evolving technology through its 3D Printing ... run alongside the expo portion of the event and ... demonstrations focused on trending topics within 3D printing and ... manufacturing event will take place June 13-15, 2017 at the ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... , ... October 12, 2017 ... ... announces publication of a United States multicenter, prospective clinical study that demonstrates ... point-of-care diagnostic test capable of identifying clinically significant acute bacterial and viral ...
(Date:10/12/2017)... ... October 12, 2017 , ... AMRI, a global contract ... to improve patient outcomes and quality of life, will now be offering its ... attributed to new regulatory requirements for all new drug products, including the finalization ...
(Date:10/11/2017)... ... October 11, 2017 , ... At its ... announced Dr. Suneel I. Sheikh, the co-founder, CEO and chief research scientist of ... been selected for membership in ARCS Alumni Hall of Fame . ASTER ...
(Date:10/11/2017)... ... 11, 2017 , ... Personal eye wash is a basic first aid supply for any work ... which eye do you rinse first if a dangerous substance enters both eyes? It’s one ... with its unique dual eye piece. , “Whether its dirt and debris, or an ...
Breaking Biology Technology:
Cached News: