Claire O’Leary

Claire O’Leary is an Assistant Professor in the Department of Pediatrics at the University of Wisconsin–Madison, School of Medicine and Public Health. She leads the O’Leary Research Group, focusing on epithelial-immune-microbiome interactions in gastrointestinal and biliary tissues. Her lab is based at the Clinical Science Center in Madison, WI, and she is affiliated with the University of Wisconsin Carbone Cancer Center and Immunology at Wisconsin.

• Position: Assistant Professor
• Division: Allergy, Immunology, and Rheumatology
• Location: H6/565 Clinical Science Center, 600 Highland Ave, Madison, WI 53706

Dr. O’Leary’s research centers on how tuft cells in the epithelial barrier regulate immune responses in harsh environments such as the gut and biliary tract. Her work explores how tissues limit inflammation despite constant exposure to acids, enzymes, and microbiome-derived ligands. She investigates the role of bile acids as signaling molecules and how they, along with microbial metabolites, influence immune cell behavior. Her studies integrate mucosal immunology, epithelial biology, and microbiome science to understand tissue homeostasis and inflammation.

Her recent publications, including in Science Immunology (2022), highlight her contributions to understanding tuft cell function in antibacterial defense and immune regulation. The research reveals tissue-specific roles of tuft cells in the small intestine, airways, and biliary tree, emphasizing their capacity to produce effector molecules like IL-25 and coordinate protective responses.

• Research Focus: Tuft cell biology, epithelial-immune crosstalk, microbiome-host interactions, bile acid signaling, mucosal immunology
• Key Models: Mouse models of inflammation, fluorescent imaging, microbiome manipulation

Dr. O’Leary has received competitive funding, including support from the Research Forward initiative, which promotes innovative research at UW–Madison. She is also associated with the Gerard B. Odell Research Award, recognizing excellence in basic or translational pediatric research among early-career faculty.

She actively mentors graduate students and is a trainer in the Cellular and Molecular Pathology (CMP), Cellular and Molecular Biology (CMB), and Microbiology Doctoral Training Programs. The O’Leary lab is currently recruiting graduate students and a T32-supported postdoctoral fellow, indicating active research expansion and training opportunities.

The O’Leary Research Group is part of a vibrant research ecosystem within the Department of Pediatrics, which ranks among the top 20 NIH-funded pediatric departments nationally. Her work contributes to broader efforts in understanding inflammatory diseases and developing novel therapeutic strategies targeting epithelial-immune communication.