Identification and multimodal characterization of a specialized epithelial cell type associated with Crohn's disease

Area of Science:

• Gastroenterology
• Immunology
• Cell Biology

Background:

• Crohn's disease (CD) is a chronic inflammatory disorder with complex immune dysregulation.
• Gastrointestinal and extra-intestinal manifestations are characteristic of CD.

Purpose of the Study:

• To identify novel cell types involved in Crohn's disease pathogenesis.
• To investigate the role of these cells in disease activity and treatment response.

Main Methods:

• Single-cell RNA sequencing of 202,359 cells from 170 specimens across 83 patients.
• In-situ RNA and protein imaging to confirm cell presence and location.
• Analysis of gene expression related to immune response and CD susceptibility.

Main Results:

• A novel epithelial cell type, termed LND cells, was identified in the terminal ileum and ascending colon.
• LND cells express high levels of LCN2, NOS2, and DUOX2, and genes involved in antimicrobial response and immunoregulation.
• LND cells are rare in controls but expand in active CD, interacting with immune cells and expressing CD susceptibility genes.
• Early and late LND subpopulations were discovered, with a higher late-to-early ratio correlating with better anti-TNF treatment response.

Conclusions:

• LND cells may play a pathogenic role in Crohn's ileitis and colitis.
• The ratio of LND subpopulations could serve as a biomarker for anti-TNF therapy response.
• Further research into LND cells could reveal new therapeutic targets for Crohn's disease.