R. William DePaolo


Assistant Professor

Molecular Microbiology and Immunology
Keck School of Medicine

Research Topics

  • Host-pathogen interaction
  • mucosal biology, immunology
  • infectious disease

Research Overview

The intestinal immune system has the difficult job of maintaining tolerant to food and commensal microflora, yet also must being able to induce protective inflammatory immune responses against invading pathogens. The focus of my laboratory is to understand the complex immune interactions that lead to tolerance and immunity at the cellular and molecular levels. We are interested in understanding how the immune system responds to intestinal pathogens such as Yersinia enterocolitica and how infections may alter the composition of commensal microflora, metabolism and inflammation in animals that have genetic defects in innate immunity. Additionally, we have initiated studies investigating these same genetic defects in patients with inflammatory bowel disease. Lastly, dietary vitamin A has been shown to promote tolerance via induction of regulatory T cells (Tregs), however our work has shown that during intestinal inflammation, vitamin A can act as an adjuvant promoting intestinal inflammatory responses and generation of Th1 and Th17 cells. Currently, we are investigating how vitamin A will affect responses to intestinal infection by Y. enterocolitica. Importantly, because vitamin A deficiency (VAD) is very prevalent in developing countries and major cause of death in children under 5 years old world wide, we are investigating how VAD as well as supplementation with vitamin A will effect immunity against a pathogens.