This recent study (summarized in earlier post today/Dr. Barnard’s talk) provides more information on the microbiome in patients with pediatric Crohn’s. Here’s a link to full article: Specific transcriptome and microbiome signature in pediatric Crohn’s Here’s the abstract:
Interactions between the host and gut microbial community likely contribute to Crohn disease (CD) pathogenesis; however, direct evidence for these interactions at the onset of disease is lacking. Here, we characterized the global pattern of ileal gene expression and the ileal microbial community in 359 treatment-naive pediatric patients with CD, patients with ulcerative colitis (UC), and control individuals. We identified core gene expression profiles and microbial communities in the affected CD ilea that are preserved in the unaffected ilea of patients with colon-only CD but not present in those with UC or control individuals; therefore, this signature is specific to CD and independent of clinical inflammation. An abnormal increase of antimicrobial dual oxidase (DUOX2) expression was detected in association with an expansion of Proteobacteria in both UC and CD, while expression of lipoprotein APOA1 gene was downregulated and associated with CD-specific alterations in Firmicutes. The increased DUOX2 and decreased APOA1 gene expression signature favored oxidative stress and Th1 polarization and was maximally altered in patients with more severe mucosal injury. A regression model that included APOA1 gene expression and microbial abundance more accurately predicted month 6 steroid-free remission than a model using clinical factors alone. These CD-specific host and microbe profiles identify the ileum as the primary inductive site for all forms of CD and may direct prognostic and therapeutic approaches.
From Cincinnati Children’s Pediatric Insights (summary of findings):
“The discovery of specific bacterial populations and a core gene signature associated with Crohn’s disease could lead to new diagnostic testing and improved treatment for inflammatory bowel disease (IBD), according to a study led by researchers at Cincinnati Children’s.
‘This study identifies a set of bacteria that are associated with symptoms, and a group of anti-inflammatory genes that are associated with intestinal damage in children with Crohn’s disease,’ says Lee (Ted) Denson, MD, Medical Director of the Inflammatory Bowel Disease Center, senior investigator for the study, published online July 8 in the Journal of Clinical Investigation. Yael Haberman Ziv, MD, was the study’s first author.
Denson’s team studied tissue samples from the ileum, the lowermost portion of the small intestine, in a large number of children with Crohn’s disease. They found specific types of bacteria and a “core” gene expression signature, both of which appear to affect inflammatory changes in the gut. Certain genes in the core signature appeared to be specifically associated with intestinal damage from deep ulcers.”