Immune system 'circuitry' that kills malaria in mosquitoes identified

June 7, 2012

Researchers at the Johns Hopkins Malaria Research Institute have, for the first time, determined the function of a series proteins within the mosquito that transduce a signal that enables the mosquito to fight off infection from the parasite that causes malaria in humans. Together, these proteins are known as immune deficiency (Imd) pathway signal transducing factors, are analogous to an electrical circuit. As each factor is switched on or off it triggers or inhibits the next, finally leading to the launch of an immune response against the malaria parasite. The study was published June 7 in the journal PLoS Pathogens.

The latest study builds upon earlier work of the research team, in which they found that silencing one gene of this circuit, Caspar, activated Rel2, an Imd pathway transcription factor of the mosquito. The activation of Rel2 turns on the effectors TEP1, APL1 and FBN9 that kill malaria-causing parasites in the mosquito's gut. More significantly, this study discovered the Imd pathway signal transducing factors and effectors that will mediate a successful reduction of parasite infection at their early ookinete stage, as well as in the later oocyst stage when the levels of infection were similar to those found in nature.

"Identifying and understanding how all of the players work is crucial for manipulating the Imd pathway as an invention to control malaria. We now know which genes can be manipulated through genetic engineering to create a malaria resistant mosquito" said George Dimopoulos PhD, professor in the Department of and Immunology at the Johns Hopkins Bloomberg School of Public Health.

To conduct the study, Dimopoulos's team used a method to "knock down" the genes of the Imd pathway. As the components were inactivated, the researchers could observe how the mosquito's resistance to would change.

"Imagine a string of Christmas lights or other circuit that will not work when parts aren't aligned in the right sequence. That is how we are working with the mosquito's immune system," explained Dimopolous. "We manipulate the molecular components of the mosquito's immune system to identify the parts necessary to kill the malaria parasites."

Malaria kills more than 800,000 people worldwide each year. Many are children.

Explore further: Scientists engineer mosquito immune system to fight malaria

More information: "Anopheles Imd pathway factors and effectors in infection intensity-dependent anti-Plasmodium action", PLoS Pathogens.

Related Stories

Scientists engineer mosquito immune system to fight malaria

December 22, 2011
Researchers at the Johns Hopkins Malaria Research Institute have demonstrated that the Anopheles mosquito's innate immune system could be genetically engineered to block the transmission of malaria-causing parasites to humans. ...

Wolbachia bacteria reduce parasite levels and kill the mosquito that spreads malaria

May 19, 2011
Wolbachia are bacteria that infect many insects, including mosquitoes. However, Wolbachia do not naturally infect Anopheles mosquitoes, which are the type that spreads malaria to humans. Researchers at the Johns Hopkins Bloomberg ...

Certain bacteria render mosquitoes resistant to deadly malaria parasite

May 12, 2011
cientists have identified a class of naturally occurring bacteria that can strongly inhibit malaria-causing parasites in Anopheles mosquitoes, a finding that could have implications for efforts to control malaria. The study, ...

Recommended for you

Researchers find factor that delays wound healing

October 17, 2017
New research carried out at The University of Manchester has identified a bacterium—normally present on the skin that causes poor wound healing in certain conditions.

Childhood poverty, poor support may drive up pregnant woman's biological age

October 16, 2017
Pregnant women who had low socioeconomic status during childhood and who have poor family social support appear to prematurely age on a cellular level, potentially raising the risk for complications, a new study has found.

Chronic inflammation plays critical role in sustained delivery of new muscular dystrophy therapy

October 16, 2017
Macrophages, a type of white blood cell involved in inflammation, readily take up a newly approved medication for Duchenne muscular dystrophy (DMD) and promote its sustained delivery to regenerating muscle fibers long after ...

Worms reveal secrets of aging: Researchers discover a conserved pathway that controls aging

October 13, 2017
Investigators at Case Western Reserve University School of Medicine and University Hospitals Health System have identified a new molecular pathway that controls lifespan and healthspan in worms and mammals. In a Nature Communications ...

New study demonstrates importance of studying sleep and eating in tandem

October 13, 2017
A new study from scientists on the Florida campus of The Scripps Research Institute (TSRI) offers important insights into possible links between sleep and hunger—and the benefits of studying the two in tandem. A related ...

'Ridiculously healthy' elderly have the same gut microbiome as healthy 30 year-olds

October 11, 2017
In one of the largest microbiota studies conducted in humans, researchers at Western University, Lawson Health Research Institute and Tianyi Health Science Institute in Zhenjiang, Jiangsu, China have shown a potential link ...

0 comments

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.