Asian tiger mosquito

The Asian tiger mosquito (above) is not the main concern for Elmer Gray, an entomologist with the University of Georgia, but they do have a habit of being a nuisance during the summer.

University of Georgia researchers Kevin Clark and Dennis Phillips took the proverb “the enemy of my enemy is my friend” to heart when starting their research on how parasitic wasps could be the first step in stopping the spread of mosquito-borne diseases.

Clark and Phillip’s paper published in PLOS One in February is the “basic research,” Clark said, for the battle against mosquito-borne diseases.

Clark, an associate research scientist in the department of food science and technology, has been researching insects’ immune systems for the past 20 years and recently shifted his focus to the melanization in the immune system, which is a similar process to skin tanning in the sun.

Insects use melanization as a defensive mechanism, Clark said, and it previously wasn’t clear how melanin was made, but he took a different approach during this research to examine the different proteins involved in the process.

“We’re looking at the insects themselves and seeing how insects carry diseases without being hurt themselves,” Clark said.

The research started with studying the biochemical processes of caterpillars when affected with parasitic wasps.

Parasitic wasps lay their eggs in or on a host insect where the wasp matures by feeding on the host’s tissue. When they are fully grown, the wasps eat through the host to emerge, according the UGA College of Agriculture and Environmental Sciences.

Clark looked at how the parasitic wasps evaded the caterpillars' immune systems and carried these findings into research on other insects.

The researchers then began to look at how parasitic pathogens like malaria evade mosquitoes’ immune systems without hurting the mosquito itself.

“We now have a deeper understanding of the immune system and a new view of how this works,” Clark said. “We can apply it to mosquitoes and see how they’re affected by different pathogens.”

Clark said with research like this, traditional biochemical techniques to study the immune systems wouldn’t work, so he went to the Proteomics and Mass Spectrometry Core Facility in the chemistry department, headed by Phillips.

“Dennis became involved because it was such a long process,” Clark said.

Phillips helped with the techniques used to isolate the immune complexes and identifying the proteins, Clark said.

This information is needed to understand how the insects are infected with the pathogen and how that pathogen is transferred to humans, Clark said.

“We have to understand how things work to solve the bigger problems,” Clark said.

Clark said he doesn’t work with treating people infected with diseases, but with this research, they can “dive a lot deeper” into the problem of mosquito-borne diseases.