Concerted changes in the pediatric single-cell intestinal ecosystem before and after anti-TNF blockade.

Distinct pediatric intestinal cell states at diagnosis predict Crohn's disease severity and response to anti-TNF therapy, with treatment shifting toward a more refractory adult-like profile.

• Why it matters: Understanding early cellular changes in pediatric Crohn's disease can improve prediction of disease progression and treatment outcomes, addressing a critical gap in personalized therapy.
• What they did: The study combined clinical data, flow cytometry, histology, and single-cell RNA sequencing of 201,883 cells from pediatric biopsies, developing the ARBOL clustering method to identify cell states and trajectories.
• The result: Findings reveal baseline cell states linked to disease severity, and anti-TNF therapy induces a shift toward an adult-like, treatment-resistant cellular ecosystem, enabling better prediction and management strategies.