Pre-Crohn's Disease Stool From Discordant Siblings Promotes the Development of Colitis in Germ-Free Mice.

Stool from siblings who later develop Crohn's disease increases colitis severity in germ-free mice, highlighting early microbial differences linked to disease risk.

• Why it matters: Understanding microbial factors that precede Crohn's disease can reveal early intervention targets and clarify disease mechanisms, addressing gaps in causal evidence from human studies.
• What they did: Fecal samples from 12 discordant sibling pairs were used to colonize germ-free mice, followed by T-cell transfer to induce colitis, with analyses of metabolites and histology to assess pathogenic traits.
• The result: Mice receiving pre-Crohn's stool showed greater inflammation and damage, with specific metabolites and sphingolipid pathways correlating with increased colitis, suggesting early microbiome alterations promote disease susceptibility.