Bite This!
Bioengineers use fake skin and real blood to study mosquito feeding.
Summer 2023
By Jade Boyd
When mosquitoes eat, they spread disease. Using 21st-century materials and tools — including fake skin that’s 3D-printed with blood vessels — Rice bioengineers have made it faster and easier for tropical disease experts to study the insects’ blood feasts.
The engineers teamed up with tropical medicine experts from Tulane University to take some of the pain out of studying mosquitoes’ blood-sucking behavior. Their bites can spread diseases like malaria, dengue and yellow fever, but setting up experiments to examine their behavior can be expensive and time-consuming.
“Many mosquito experiments still rely on human volunteers and animal subjects,” says Kevin Janson ’23, a bioengineering graduate student and lead co-author of a recently published study about the experiment.
Janson and his co-authors found a way to automate the collection and processing of mosquito feeding data using inexpensive cameras and machine-learning software. To eliminate the need for live volunteers, their system uses synthetic skin made with a 3D printer. Each patch of gelatin-like hydrogel comes complete with tiny passageways that can be filled with flowing blood.
In feeding tests, Janson and his adviser and co-author, Omid Veiseh, place as many as six of the hydrogel skin patches inside a transparent plastic box about the size of a volleyball surrounded by cameras. When mosquitoes enter the chamber, the cameras record how often they land at each location, how long they stay, whether or not they bite, how long they feed and the like.
The system was tested at the laboratory of Tulane mosquito expert Dawn Wesson. In the proof-of-concept experiments featured in the study, Wesson, Janson and co-authors used the system to examine the effectiveness of existing mosquito repellents made with either DEET or a repellent derived from the oil of lemon eucalyptus plants. Tests showed mosquitoes readily fed on hydrogels without any repellent and stayed away from hydrogel patches coated with either product. While DEET was slightly more effective, both repellents deterred mosquitoes.
Veiseh says the results suggest the behavioral test system can be scaled up to test or discover new repellents and to study mosquito behavior more broadly. The system could also open the door for testing in labs that couldn’t previously afford it.
“It provides a consistent and controlled method of observation,” he adds. “The hope is researchers will be able to use that to identify ways to prevent the spread of disease in the future.”
Omid Veiseh is assistant professor of bioengineering at Rice. Dawn Wesson is associate professor of tropical medicine at Tulane’s School of Public Health and Tropical Medicine.