Noninvasive Evaluation Can Help Determine Infliximab's Efficacy in IBD

A noninvasive evaluation determining the severity of inflammatory bowel disease (IBD) and the treatment efficacy of infliximab is made possible by locating universal biomarkers in human fecal microbiota, according to a study published by the American Society for Microbiology's mSystems.

An increase in industrialization across the world has caused an increase of IBD among populations in less developed regions; ulcerative colitis (UC) and Crohn disease (CD) are the 2 main clinical types of IBD, with global incidence of these diseases on the rise.

The etiology of these conditions is not well understood; however, past research has suggested that an imbalance of gut microbiota may be the main cause of IBD. In the literature, IBD patients when compared to healthy individuals have a reduced biodiversity, a decreased abundance of several taxa in the Firmicutes phylum, and an increased abundance of Gammaproteobacteria throughout the digestive system.

In the study, researchers profiled the fecal microbiota from a cohort of Chinese patients with IBD, then compared the results to 2 western IBD cohorts by using bar-coded 165 rRNA amplicon sequencing. IBD patients included in the study were also compared to healthy western and Chinese individuals. This was a multicenter association study in which over 1000 treatment-naïve patients participated.

The goals of the study were to locate the microbiota patterns in Chinese IBD patients with different disease activities, discover different gut microbiota patterns across ethnicities and geographic locations, and to recognize any universal biomarkers across the IBD cohorts that could indicate and predict disease progression and infliximab treatment efficacy.

1,376,142 rRNA gene sequences were taken from 196 samples. A microbial imbalance of gut microbiota patterns was found in Chinese IBD patients. In addition, researchers recognized that the sequencing of gut microbiota in Chinese IBD patients was similar to those of the western cohorts. Researchers also saw gut microbiota being restored during disease remission while certain microbes, like Clostridiales, displayed the body’s response to infliximab treatment of CD.

In patients with IBD, it was found that gut microbial levels lack in diversity. After receiving infliximab treatment, CD patients restored their microbial diversity and increased their Clostridiales levels. Clostridiales reduced proinflammatory bacteria, produced short-chain fatty acids, and induced an immune response.

“Our results reinforce the idea that the gut microbiota contains promising biomarkers for the noninvasive evaluation of IBD activity and assessment of therapeutic responses,” the authors concluded. “The identification of [a] disease-activity associated microbiome is a step toward establishing a set of microbiota-based biomarkers for the assessment of treatment and progression of inflammatory bowel disease.”

Reference

Zhou Y, Xu ZZ, He Y, et al. Gut microbiota offers universal biomarkers across ethnicity in inflammatory bowel disease diagnosis and infliximab response prediction. mSystems. 2018;3(1):e00188-17. doi: 10.1128/mSystems.00188-17.