
Microbiology and Immunology faculty conduct research in the areas of microbial pathogenesis. These include those interested in viral pathogens including DNA and RNA viruses that cause acute and persistent infections of humans and model organisms. For bacterial pathogens, both gram-positive and gram-negative mucosal and intracellular pathogens as well as select agents are under investigation. In addition, toxin secretion, antimicrobial and therapeutic agent discovery, vaccine development, and mathematical modeling of infection represent ongoing research efforts. Fungal and protozoan eukaryotic pathogens are examined with respect to their effect on immune system development and invasion, respectively.
Our faculty, students, and fellows are also engaged in several areas of research pertaining to innate immunity. Central to innate defense against pathogenic microorganisms is the ability of innate immune cells such as macrophages to internalize particles by phagocytosis.

With respect to adaptive immunity, basic questions relating to the role of T and B lymphocytes, intracellular signaling mechanisms regulating T cell development and activation, and immunoglobulin class switch recombination in B cells using bacterial artificial chromosome transgenesis are under study.

The study of cell biology of infection focuses on host-pathogen interactions. This reveals information about disease but also sheds light on fundamental mechanisms of normal cellular function. Research approaches use live cell imaging to show that microbes take advantage of the host cell niche by manipulating cellular trafficking pathways. Intracellular bacterial pathogens exploit infected host cells to acquire nutrients and regulate differentiation. Other efforts focus on antimicrobial responses and release of inflammatory mediators, chemical signals (calcium and NADPH), and eukaryotic cell cycle regulation.
Humans are colonized with a vast array of microbes that directly influence our physiology. These microbes not only direct the development of our immune system and resistance to infection, but also affect metabolism and our susceptibility to diseases such as diabetes, colorectal cancer and inflammatory bowel disease. Many of our faculty are engaged in research towards a better understanding of the host microbiome that exists between animals and their colonizing microbes. This research includes tracking the changes in the host microbial community between healthy and disease states, as well as a detailed understanding of the physiology of the microbes that shape our health.