Navigating the Microbial Basis of Inflammatory Bowel Diseases: Seeing the Light at the End of the Tunnel

Abstract

Inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis, are chronic inflammatory conditions affecting the gastrointestinal tract with variable presentations and disease courses. The cause of IBD is unknown, but it is hypothesized that individuals with a genetic predisposition to disease develop an aberrant immune response to environmental triggers. Evidence suggests that microbiota residing in the gastrointestinal tract play an important role in the development and perpetuation of the disease. In this review, we discuss the role of microbes in the development of a healthy gut, their role in the development of diseases in general, and their role in the development of IBD. Advances in molecular technologies and bioinformatics will continue to further our insight into the structure of the microbial community, the function of the microbial community as a whole, and the interaction of this community with the host immune system. The latter two are crucial to understanding the role of microbes in IBD. The field has advanced significantly in recent years, and the future is very promising as we begin to elucidate the microbial basis of IBD.

Keywords: Colitis; Crohn disease; Inflammatory bowel disease; Microbial; Microbiota; ulcerative.

Fig. 1

Factors influencing the gut microbiome after birth. Many genetic and environmental factors influence the infant gut microbiome. Exposure to the mother’s microbiome, beginning with the birthing process, and an infant’s genetic background, diet and competitive selection among the microbes themselves are all important factors for the development of the microbiome.

Fig. 2

The role of the gut microbiome in inflammatory bowel diseases. Although the microbial composition of the gut microbiota is important for health, recent studies have recognized the importance of the function of the microbial community and the host-microbial interaction in health and disease.