Summary of the focus of the research of Dr. Jianyun Liu

My long term research interests include understanding immunological responses to the invasion of pathogens and tumors, and how modern lifestyle alters the immune system.

Description and summary of research focus of the laboratory

Modern lifestyle and diet not only contribute to the global epidemic of obesity, but also change the diversity of microbiota. It is not clear how altered microbiota in obesity link to chronic inflammation. Mucosal-associated innate T (MAIT) cells are recently identified innate T cells, and their development and maturation require commensal bacteria and MR1, the antigen presenting molecule for MAIT cells. MAIT cells are similar in some ways to another innate T cells that have been well-studied in our laboratory, Natural Killer T (NKT) cells. MAIT cells are significantly reduced in obese patients. Bacteria-derived vitamin B metabolites have been identified as the antigens that activate MAIT cells. We will study how MR1 molecules are processed and loaded with bacterial antigens in antigen presenting cells (APCs) before they reach the cell surface to activate MAIT cells. The goal is to understand the impact of obesity on MAIT cell function and its application in obesity-related diseases.