Impact of Interleukin 10 Deficiency on Intestinal Epithelium Responses to Inflammatory Signals.

Stamatia Papoutsopoulou,Raheleh Sheibani-Tezerji,Werner Müller,Barry J Campbell,Liam Pollock,William Tench,Catherine Walker,Vitor A P Martins Dos Santos,Mohammad Tauqeer Alam,Luca Lenzi,Sakim Shakh Samad,François Bergey,Phillip Rosenstiel

doi:10.3389/fimmu.2021.690817

Abstract

Interleukin 10 (IL-10) is a pleiotropic, anti-inflammatory cytokine that has a major protective role in the intestine. Although its production by cells of the innate and adaptive immune system has been extensively studied, its intrinsic role in intestinal epithelial cells is poorly understood. In this study, we utilised both ATAC sequencing and RNA sequencing to define the transcriptional response of murine enteroids to tumour necrosis factor (TNF). We identified that the key early phase drivers of the transcriptional response to TNF within intestinal epithelium were NFκB transcription factor dependent. Using wild-type and Il10−/− enteroid cultures, we showed an intrinsic, intestinal epithelium specific effect of IL-10 deficiency on TNF-induced gene transcription, with significant downregulation of identified NFκB target genes Tnf, Ccl20, and Cxcl10, and delayed overexpression of NFκB inhibitor encoding genes, Nfkbia and Tnfaip3. IL-10 deficiency, or immunoblockade of IL-10 receptor, impacted on TNF-induced endogenous NFκB activity and downstream NFκB target gene transcription. Intestinal epithelium-derived IL-10 appears to play a crucial role as a positive regulator of the canonical NFκB pathway, contributing to maintenance of intestinal homeostasis. This is particularly important in the context of an inflammatory environment and highlights the potential for future tissue-targeted IL-10 therapeutic intervention.

Highlights

Interleukin 10 (IL-10) is an anti-inflammatory cytokine that is synthesized and secreted by lymphocytes (T and B cells), macrophages, dendritic cells, and some epithelial cells [1, 2]
In the ‘common’ group, we identified some known genes involved in classical NFkB signalling pathway, such as Nfkbia, Tnfaip3 [encoding A20, an inducible inhibitor of NFkB [54, 55]], Nfkbiz [encoding a member of the ankyrin-repeat family with high sequence similarity to the IkB family of proteins [56]], and NFkB target genes such as Irf1 [encoding an activator of interferons [57]], and Ccl20 [encoding a chemokine recruited to inflammatory sites [58]]; see Figure 1E
We have established an Assay for Transposase-Accessible Chromatin (ATAC) sequencing protocol for use with murine enteroids in order to study the transcriptional effects of tumour necrosis factor (TNF)

Summary

Introduction

Interleukin 10 (IL-10) is an anti-inflammatory cytokine that is synthesized and secreted by lymphocytes (T and B cells), macrophages, dendritic cells, and some epithelial cells [1, 2]. The major role of IL-10 in intestinal homeostasis was revealed by genetic intervention in mice, where it was shown that both IL-10 deficient and IL-10 receptor deficient mice develop spontaneous colitis [7, 8]. Further studies using transgenic animals have revealed that IL-10 receptor signalling in macrophages [14, 15] and T cells [16] is critical for intestinal homeostasis and that absence contributes to the development of intestinal inflammation. Murine intestinal epithelial cells express functional IL-10 receptor, that upon addition of IL-10 downregulate cellsurface major histocompatibility complex (MHC) class II molecule expression induced by interferon gamma [17]

Methods

Results

Conclusion