Clin Immunol. 2020 Apr 9;215:108415. doi: 10.1016/j.clim.2020.108415.Online ahead of print.

Amanda Ricciuto ¹, Philip M Sherman ², Ronald M Laxer ³

Author information

¹Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada; Department of Paediatrics, Faculty of Medicine, University of Toronto, Canada. Electronic address: amanda.ricciuto@sickkids.ca.

²Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada; Department of Paediatrics, Faculty of Medicine, University of Toronto, Canada. Electronic address: philip.sherman@sickkids.ca.

³Department of Paediatrics, Faculty of Medicine, University of Toronto, Canada; Division of Rheumatology, The Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada. Electronic address: ronald.laxer@sickkids.ca.

Abstract

The gut microbiota is integral to human health, including maintaining the delicate balance between tolerance and protection against potentially harmful pathogens. A growing body of evidence implicates the intestinal microbiome in immune-mediated inflammatory disorders; these data span the spectrum from genetic and environmental disease risk factors, to animal studies (particularly germ-free and gnotobiotic models) and human studies, including evidence of dysbiosis in diseased individuals compared to healthy populations. In this review, we summarize both animal and human data supporting a link between the gut microbiota and inflammatory bowel diseases (IBD) and systemic inflammatory arthritis, as models for chronic inflammatory disorders, while offering a pediatric focus (pediatric IBD and juvenile idiopathic arthritis). We discuss relevant mechanisms related to the crosstalk between the gut microbiota and the innate and adaptive immune system. We close with a brief discussion of emerging microbe-altering interventions, including fecal microbial transplantation and its immunologic effects.