To stop disease spread, K-State researchers give mosquitoes a taste of their own medicine.
When mosquitos ruin a beautiful summer night by treating you like an all-you-can-eat buffet, who cares if these blood suckers get sick? Well, two K-State biologists do.
Bianca Morejon and Kristin Michel might be in the minority when it comes to thinking about a mosquito’s immune system, but their research could protect a lot of us from mosquito-borne pathogens.
“Mosquitoes get infected with the same pathogens they ultimately inject into us,” said Morejon, a now-graduated doctoral candidate and former recipient of K-State’s Sarachek Predoctoral Honors Fellowship. “If we can understand how to boost their immune systems so they can kill a pathogen before it ever gets to us, we can create better mosquito control methods and insecticides.”
Morejon and Michel, a professor of biology, made groundbreaking discoveries about the immune system of the African malaria mosquito. They published their findings in one of the world’s preeminent scientific journals, Proceedings of the National Academy of Sciences.
A mosquito has serine protease cascades that can enable its immune system to kill bacteria directly or “cocoon” invading pathogens with melanin, making them harmless.
So how does a person make a mosquito sick?
In a bit of poetic justice, Morejon injected 100,000 female mosquitoes by anesthetizing them and using a thin glass needle to inject them with double-stranded RNA that could knock down genes selectively.
As part of her doctoral work, Morejon spent three years observing how different proteases affected the mosquito immune system. She measured immune system changes by observing the color of mosquito waste and by measuring whether their hemolymph or “blood” can inhibit bacterial growth.
Their research, supported with grants from the National Institutes of Health and the USDA’s National Institute of Food and Agriculture, as well as seed funding from K-State’s game-changing Research Initiation Program, could inform future disease control efforts, either by boosting or defeating mosquitoes’ immune system.
Written by: Heather Ackerly
Curated from: https://www.k-state.edu/news/articles/2025/05/bianca-morejon-kristin-michel-mosquito-immune-system-functions.html
