Roles of Gut Bacteriophages in the Pathogenesis and Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, are a group of chronic inflammatory disease, which occurs mainly in the gastrointestinal tract. Although the pathogenesis of IBD are not entirely clear yet, the complex interaction between the genetics, immune response, and environmental or microbial factors are presumed to be the main causes. Currently, lots of the studies focusing on the role of gut microbiota, especially the bacteria in the development of IBD. However, the gut microbiota comprises other microbial community as well, among of them, the bacteriophage (phage) occupy the majority in population. Phages are prokaryote virus that infects bacteria, and can be categorized into lytic or lysogenic. The lytic phages are capable of killing their bacterial host, thus modulating the composition of intestinal bacteria. Furthermore, phages can also modulate immune response and mediate the anti-inflammatory pathway, thereby aggravate or alleviate the symptom of IBD. The aim of this review is to highlight the role of gut phages in IBD pathogenesis and explore the potentiality of phages as a therapeutic target for IBD treatment. This review will facilitate understanding of the specific interactions between gut phages and human disease.