Deep learning-based image analysis reveals significant differences in the number and distribution of mucosal CD3 and

Elin Synnøve Røyset1,2,3, Henrik P Sahlin Pettersen1,2, Weili Xu4

  • 1Department of Clinical and Molecular Medicine (IKOM), Faculty of Medicine and Health Sciences (MH), NTNU - Norwegian University of Science and Technology, Trondheim, Norway.

Insights

Deep learning reveals distinct immune cell patterns in inflammatory bowel disease (IBD). Ulcerative colitis (UC) and Crohn

Area of Science:

  • Gastroenterology and Immunology
  • Computational Pathology
  • Digital Health

Background:

  • Immune cell distribution in colon mucosa differs between ulcerative colitis (UC) and Crohn's disease (CD), posing diagnostic challenges.
  • Assessing these differences visually is difficult, necessitating advanced quantitative methods.
  • Deep learning on whole slide images (WSIs) offers a powerful approach to analyze complex cellular patterns in IBD.

Purpose of the Study:

  • To explore the distribution of CD3 and gamma-delta (γδ) T cells in colon mucosal compartments in active and inactive inflammatory bowel disease (IBD).
  • To quantitatively compare these immune cell populations between CD, UC, and healthy controls (HCs) using deep learning.
  • To investigate the impact of disease activity and treatment on T cell distribution.

Main Methods:

  • Deep learning-based segmentation and cell detection were applied to WSIs from CD (n=37), UC (n=58), and HC (n=33) cohorts.
  • Quantification of CD3 and γδ T cells was performed within and beneath the epithelium and in the lamina propria of proximal and distal colon.
  • The Nancy histological index was used to define disease activity.

Main Results:

  • Inactive CD showed fewer intraepithelial γδ T cells than inactive UC but higher total CD3 cells compared to UC and HCs.
  • Active disease led to a significant loss of intraepithelial γδ T cells in UC, but not in CD.
  • Intraepithelial CD3 T cells remained constant irrespective of disease activity in both CD and UC.
  • Proximal colon mucosa had higher numbers of CD3 and γδ T cells than distal colon.
  • Oral corticosteroids impacted γδ T cell numbers, while age, gender, and disease duration did not.

Conclusions:

  • Deep learning-based quantification reveals significant differences in CD3 and γδ T cell distribution within colon mucosal compartments between CD, UC, and HCs.
  • Distinct inflammatory patterns, particularly in the epithelial compartment, can be identified using this computational approach.
  • This method provides a valuable tool for objective assessment and potential subtyping of IBD.