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IsolatorThe National Gnotobiotic Rodent Resource Center (NGRRC) is a nationwide resource for germ-free and gnotobiotic mice and associated services. Gnotobiotic means “known life” and refers to the selective colonization of germ-free mice with microbes. The Center is an expansion of the Gnotobiotic Core of the Center for Gastrointestinal Biology and Disease (CGIBD), an NIH-NIDDK funded Digestive Diseases Research Core Center at UNC-Chapel Hill and North Carolina State University. Equipment for the expansion of the CGIBD Gnotobiotic Core was provided initially by a North Carolina Biotechnology Center grant with additional funds from the UNC-CH School of Medicine and from an administrative supplement to the CGIBD. In 2004, we leveraged our expertise in gnotobiotics to obtain a grant from the NIH’s National Center for Research Resources, Comparative Medicine Group to establish the NGRRC. Current funding for the NGRRC is provided primarily by the NIH Office of the Director (P40OD010995), with additional funds from the CGIBD’s NIDDK grant (P30DK034987) and the Crohn’s and Colitis Foundation.


We provide germ-free and gnotobiotic mice and expertise, including germ-free rederivation, to investigators across the country whose research focuses on areas such as diabetes, metabolic syndrome, atherosclerosis, arthritis and intestinal biology and disease. In addition, we support pilot studies for investigators to generate preliminary results for grant applications. We also offer a 4-day hands-on training course for technical staff from institutions planning to establish their own gnotobiotic facilities.


R. Balfour Sartor, MD, Director, is the Midget Distinguished Professor of Medicine, Microbiology and Immunology at the University of North Carolina (UNC), where he specializes in inflammatory bowel diseases (IBD) and directs the UNC Multidisciplinary IBD Center. Dr. Sartor has been a faculty member at UNC for his entire academic career, where he is the  Co-Director of the Center for Gastrointestinal Biology and Disease and former Co-Chief of the Division of Gastroenterology and Hepatology (Research). His research focuses on developing and applying rodent models of chronic, immune-mediated intestinal inflammation relevant to IBD, investigating host-microbial interactions and performing clinically relevant translational studies of IBD patients. Dr. Sartor investigates host genetically programmed immune responses to luminal resident bacteria using gnotobiotic rodents and patient-derived samples and studies the influence of dietary and environmental factors on intestinal microbiota composition and function.

Allison Rogala, DVM, DACLAM, Co-Director, serves as the liaison between The National Gnotobiotic Rodent Resource Center and the Department of Comparative Medicine.  She supervises the sterile embryo transfers and Caesarean sections to derive new germ-free mouse lines.  She is responsible for the health of our rodent population as well as the cryopreservation of embryos and sperm for all breeding stock.

Josh Frost, BA, RLATg is the Facility Manager.  He supervises all technical staff and trains animal technicians.  He is responsible for the day-to-day management of the facility.

Susan Tonkonogy, PhD, is the Director of the Gnotobiotic Core at North Carolina State University which is part of the Center for Gastrointestinal Biology and Disease at UNC-CH.  Dr. Tonkonogy has extensive expertise with experimental design using gnotobiotic rodents.  As a member of the NGRRC Steering Committee, her role is to respond to initial inquires from investigators who are considering mice and services from the NGRCC.