Author: James  Thomas  Seuch

Major: Biochemistry & Molecular and Cellular Biology

Graduation Year: 2020

Thesis Advisor: Benjamin King

Description of Publication: The CDC estimated that seasonal influenza A virus (IAV) infections resulted in 490,600 hospitalizations and 34,200 deaths in the US in the 2018-2019 season. The longterm goal of our research is to understand how to improve innate immune responses to IAV. During IAV infection, neutrophils and macrophages initiate a respiratory burst response where reactive oxygen species (ROS) are generated to destroy the pathogen and recruit additional immune cells. While ROS molecules, such as hydrogen peroxide, help clear the virus, the signaling cascade can also lead to excess neutrophil recruitment, hyperinflammation, and tissue damage. Regulatory mechanisms that trigger overactivation of neutrophils are not understood. We are developing a zebrafish (Danio rerio) transgenic fluorescent reporter line to study neutrophil function and hydrogen peroxide concentration during IAV infection in vivo. Using Tol2 transgenesis, we are developing this line to express the hydrogen peroxide biosensor protein, HyPer, specifically in neutrophils. HyPer fluoresces at different wavelengths dependent on the concentration of hydrogen peroxide. We have designed the genetic construct to drive the expression of HyPer using the promoter of a gene highly expressed in neutrophils, myeloid peroxidase (mpx). Once developed, we plan to cross the line, named Tg(mpx:HyPer), to the neutrophil reporter line, Tg(mpx:GFP), and use offspring to visualize how neutrophils generate ROS in response to localized IAV infection. The Tg(mpx:HyPer);Tg(mpx:GFP) line may also be used to study neutrophil function and ROS in bacterial, fungal and other viral infections.

Location of Publication:

URL to Thesis: https://digitalcommons.library.umaine.edu/honors/614/