Michael Howitt, PhD, Assistant Professor, Department of Microbiology and Immunology, Stanford University

Research Description: The Howitt lab aims to understand the interplay between the gut microbiota and the immune system. Mucosal surfaces, like the gut, must carefully balance immune tolerance towards commensal microbes with protection against pathogens. We are interested in how the innate and adaptive immune cells decipher microbial signals to maintain health and how this process falters in various diseases. While bacteria are the quintessential members of the microbiome, we found numerous species of single-celled eukaryotes called protists, which are quite common in the mammalian gut, including in humans. These protists are not overtly pathogenic but strongly influence the host’s immune system. As a result, these protists act as a lever to alter the outcome of several diseases. In particular, we study type 2 immunity, typically associated with anti-parasite immunity, allergy, and asthma. However, our lab discovered several new aspects of type 2 immunity, including antigen sampling in mucosal lymphoid tissues and antigen-specific immune responses in the gut. Dr. Howitt actively collaborates with NORC member, Dr. Sonnenburg.