1Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
2Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
3Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
4Department of Medicine, Section of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, Texas
5Department of Immunology, Duke University, Durham, North Carolina
6Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill/North Carolina State University, Chapel Hill, North Carolina