University Scholar Nancy Freitag

Nancy Freitag, professor of microbiology and immunology. Photo: Jenny Fontaine

Nancy Freitag studies how human pathogenic bacteria infect cells, and how cells work to repel or prevent bacterial infection.

She uses the Listeria bacterium, which is responsible for deadly food-borne outbreaks, and mouse models to study these interactions.

“I look at very basic questions, such as what do bacteria need to replicate inside cells, to how infections can spread from mother to baby during fetal development,” said Freitag, professor of microbiology and immunology in the College of Medicine.

Her findings using Listeria are often applicable to other bacterial pathogens.

“We just didn’t know very much about how bacteria live once they gain entry into human cells, and what are the basic mechanisms used by cells to fight off intruders,” Freitag said.

This lack of knowledge, and exciting new developments in genetic techniques, led her to gravitate towards the field, she said.

“I was a post-doctoral scientist at the University of Pennsylvania when my mentor, Dr. Daniel Portnoy, got me interested and excited about bacterial pathogenesis,” she said.

More recently, Freitag has turned her attention to the relationship between use of anesthesia during surgery and microbial infection. Some studies have suggested that anesthesia may increase susceptibility to infections, including hospital-acquired infections. These infections account for billions of dollars in health care costs, Freitag explains, so developing strategies to prevent them is key.

“If we can understand how anesthesia influences risk for infection, then we can take steps to limit that risk,” she said.

Freitag has been selected as the American Society for Microbiology Distinguished Lecturer. In 2016, she was elected a fellow to the American Academy of Microbiology. She is senior editor of Infection and Immunity, and serves on the editorial boards of a number of other journals.