Researchers identify a means of controlling a parasite that kills and eats human cells

Jan 18, 2008

Researchers from the University of Virginia and the University of Vermont have discovered a means of inhibiting one of the world’s most voracious parasites. The study, published Friday, January 18 in PLoS Pathogens, targets a protein which aids the parasite in ingestion of immune cell corpses.

Entamoeba histolytica, which causes inflammation of the colon (colitis), plays dirty. It attacks and kills human immune cells in seconds. Then the parasite hides the evidence by eating the cells’ corpses. While doing so, it kills nearly 100,000 people each year.

The research team, led by Dr. William Petri, hypothesized that identifying molecules involved in the corpse ingestion might provide insight into how the amebae cause colitis in children.

The team identified a particular protein on the surface of the ameba called a kinase, PATMK. Using a special technique called RNA interference to inhibit the actions of this kinase, they prevented the ameba from eating dead cells.

“By blocking this kinase, we have for the first time prevented the ameba from colonizing and invading the gut,” said Dr. Petri. “This means that we are a step closer to preventing this disease, which wreaks havoc among children worldwide.”

“Infection and further invasion into the gut require the clearance of dead cells in order to prevent immune recognition of the damaged tissue,” says fellow researcher Douglas Boettner. “PATMK is the first individual member of a large family of proteins to be assigned a function related to the clearance of dying tissue during pathogenesis.”

This protein may be a pivotal vaccination target because these preliminary studies show that alterations in PATMK function reduces progression of amoebiasis in mice, Boettner added. “A vaccine that ultimately would prevent this amoeba from clearing the damaged host may attract helpful immune cells which may recognize and eliminate this infection.”

On a global basis, amebiasis affects approximately 50 million people each year, causing diarrhea, malnutrition and nearly 100,000 deaths.

This work shows how infection is dependent upon the ameba’s consumption of dead cells. By identifying the molecule that controls eating, scientists are one step closer to the ultimate goal of preventing disease caused by this parasite.

Source: Public Library of Science

Explore further: Italian olive tree disease stumps EU

add to favorites email to friend print save as pdf

Related Stories

Vaccines from a reactor

Mar 02, 2015

In the event of an impending global flu pandemic, vaccine production could quickly reach its limits, as flu vaccines are still largely produced in embryonated chicken eggs. Udo Reichl, Director at the Max ...

Looking for alternatives to antibiotics

Mar 02, 2015

Bacteria that talk to one another and organize themselves into biofilms are more resistant to antibiotics. Researchers are now working to develop drugs that prevent bacteria from communicating.

The super-resolution revolution

Feb 27, 2015

Cambridge scientists are part of a resolution revolution. Building powerful instruments that shatter the physical limits of optical microscopy, they are beginning to watch molecular processes as they happen, ...

Recommended for you

Dairy farms asked to consider breeding no-horn cows

3 hours ago

Food manufacturers and restaurants are taking the dairy industry by the horns on an animal welfare issue that's long bothered activists but is little known to consumers: the painful removal of budding horn ...

Italian olive tree disease stumps EU

Mar 27, 2015

EU member states are divided on how to stop the spread of a disease affecting olive trees in Italy that could result in around a million being cut down, officials said Friday.

China starts relocating endangered porpoises: Xinhua

Mar 27, 2015

Chinese authorities on Friday began relocating the country's rare finless porpoise population in a bid to revive a species threatened by pollution, overfishing and heavy traffic in their Yangtze River habitat, ...

A long-standing mystery in membrane traffic solved

Mar 27, 2015

In 2013, James E. Rothman, Randy W. Schekman, and Thomas C. Südhof won the Nobel Prize in Physiology or Medicine for their discoveries of molecular machineries for vesicle trafficking, a major transport ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.