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: Wolbachia bacteria reduce parasite levels and kill the mosquito that spreads 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. ...

Recommended for you

Flu study, on hold, yields new vaccine technology

September 2, 2015

Vaccines to protect against an avian influenza pandemic as well as seasonal flu may be mass produced more quickly and efficiently using technology described today by researchers at the University of Wisconsin-Madison in the ...

We've all got a blind spot, but it can be shrunk

August 31, 2015

You've probably never noticed, but the human eye includes an unavoidable blind spot. That's because the optic nerve that sends visual signals to the brain must pass through the retina, which creates a hole in that light-sensitive ...

Biologists identify mechanisms of embryonic wound repair

August 31, 2015

It's like something out of a science-fiction movie - time-lapse photography showing how wounds in embryos of fruit flies heal themselves. The images are not only real; they shed light on ways to improve wound recovery in ...

New 'Tissue Velcro' could help repair damaged hearts

August 28, 2015

Engineers at the University of Toronto just made assembling functional heart tissue as easy as fastening your shoes. The team has created a biocompatible scaffold that allows sheets of beating heart cells to snap together ...

Fertilization discovery: Do sperm wield tiny harpoons?

August 26, 2015

Could the sperm harpoon the egg to facilitate fertilization? That's the intriguing possibility raised by the University of Virginia School of Medicine's discovery that a protein within the head of the sperm forms spiky filaments, ...

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.