MHC class II antigen presentation by intestinal epithelial cells fine-tunes bacteria-reactive CD4 T cell responses

Heuberger, C.E. et al. (2023) MHC class II antigen presentation by intestinal epithelial cells fine-tunes bacteria-reactive CD4 T cell responses. Mucosal Immunology, (doi: 10.1016/j.mucimm.2023.05.001) (PMID:37209960) (In Press)

Abstract

Although intestinal epithelial cells (IECs) can express major histocompatibility complex class II (MHC II), especially during intestinal inflammation, it remains unclear if antigen presentation by IECs favours pro- or anti-inflammatory CD4+ T cell responses. Using selective gene ablation of MHC II in IECs and IEC organoid cultures, we assessed the impact of MHC II expression by IECs on CD4+ T cell responses and disease outcomes in response to enteric bacterial pathogens. We found that intestinal bacterial infections elicit inflammatory cues that greatly increase expression of MHC II processing and presentation molecules in colonic IECs. Whilst IEC MHC II expression had little impact on disease severity following Citrobacter rodentium or Helicobacter hepaticus infection, using a colonic IEC organoid-CD4+ T cell co-culture system, we demonstrate that IECs can activate antigen-specific CD4+ T cells in an MHC II-dependent manner, modulating both regulatory and effector Th cell subsets. Furthermore, we assessed adoptively transferred H. hepaticus-specific CD4+ T cells during intestinal inflammation in vivo and report that IEC MHC II expression dampens pro-inflammatory effector Th cells. Our findings indicate that IECs can function as non-conventional antigen presenting cells and that IEC MHC II expression fine-tunes local effector CD4+ T cell responses during intestinal inflammation.

• Item Type: Articles
• Status: In Press
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Maloy, Professor Kevin
• Authors: Heuberger, C.E., Janney, A., Ilott, N., Bertocchi, A., Pott, S., Gu, Y., Pohin, M., Friedrich, M., Mann, E.H., Pearson, C., Powrie, F.M., Pott, J., Thornton, E., and Maloy, K.J.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Mucosal Immunology
• Publisher: Elsevier
• ISSN: 1933-0219
• ISSN (Online): 1935-3456
• Published Online: 19 May 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Mucosal Immunology 2023
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
313264		Regulation of intestinal immune homeostasis by NOD-like receptors	Kevin Maloy	Wellcome Trust (WELLCOTR)	102972/A/13/Z	III - Immunology