Jessica Tung

Program: Molecular Microbiology and Microbial Pathogenesis

Current advisor: Rotating in the lab of Drew Schwartz, MD, PhD

Undergraduate university: University of Texas – Arlington

Research summary
Bacteroides fragilis is the leading cause of anaerobic sepsis. Aside from clinical understanding of risk factors for this (underlying disease, abdominal infection/surgery, little is known about the molecular mechanisms by which this organism traverses the colonic barrier to cause systemic infection. The Wardenburg lab has determined that toxigenic B. fragilis is able to occupy the lamina propria. We hypothesize that this tissue location should alter how the host immune system sees this organism, especially as LP localization happens during antigenic priming in the neonatal gut.

Project #1: T cell response to neonatal B. fragilis colonization
I investigated the T cell response to neonatal B. fragilis colonization by transferring OT-II cells into mouse pups colonized with OVA-expressing strains of B. fragilis. The colonic immune cells of mice colonized with enterotoxigenic vs. non-enterotoxigenic B. fragilis strains were harvested and analyzed using CYTOF.

Project #2: Adaptive immunity to sepsis with neonatal enteric B. frag colonization
I investigated the adaptive immune response to neonatal enteric B. fragilis colonization by inoculating pre-colonized pups (enterotoxigenic vs. non-enterotoxigenic B. fragilis) with enterotoxigenic B. fragilis through the bloodstream. The pups were monitored over 5 days for changes in weight/activity/appearance.

Graduate publications