Intestinal barrier alterations in mice following fecal microbiota transplant from children of IBD-affected mothers

Background: Inflammatory bowel disease (IBD) carries a hereditary risk, which is higher through maternal, rather than paternal, inheritance. Like their mothers, children born to mothers with IBD have an altered microbiome shortly after birth. Methods: To investigate whether this altered microbiome persists later in life and affects the intestinal mucosa, the fecal microbiome was analyzed in samples from 44 infants ranging from 0 to 10 years of age born to 26 women with IBD. Forty-four age-matched children of 29 women without IBD served as controls. Fecal microbiota transplantation (FMT) to germ-free mice was carried out from 4-year-olds born to mothers with IBD and controls. Markers of inflammation, barrier function, and metabolic changes were investigated. Findings: Intestinal microbiomes were more similar between women with IBD and their children than between control mothers and their offspring. Microbial changes were noticeable in children from mothers with IBD from the age of 4 years compared to children of controls. No inflammatory response was present in the mucosa of mice receiving FMT from children of mothers with IBD; however, mesenteric lymph node enlargement and decreased expression of barrier genes Zo1 and Ocln were seen in mice receiving FMT from these children compared to controls. Additionally, reduced colonic expression of the immunological tolerance enzyme Ido1 coincided with decreased serum kynurenine/tryptophan ratios. Conclusions: Fecal microbiomes of children of mothers with IBD exhibit characteristics that reduce epithelial tight junction barrier genes and tolerogenic tryptophan metabolism. Microbiome-induced gut barrier disruptions may contribute to an enhanced IBD predisposition in infants of mothers with IBD. Funding: This work was funded by ZonMw.