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

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.

Interleukin-10 Deficiency Impacts on TNF-Induced NFκB Regulated Responses In Vivo

“…TNF injection induced the transcription of Tnf in the intestinal epithelium of wild-type mice, a result similar to that which others, and our group, have reported previously [ 24 , 31 , 48 ]. There was clear impairment of Tnf mRNA induction in Il10 −/− small intestinal tissue, supporting our earlier in vitro studies where we clearly showed defective TNF-induced transcriptional activation of the Tnf gene in IL-10-deficient intestinal epithelium [ 24 ]. Real-time qPCR results were further validated by the measurement of TNF protein levels, which showed a 50% reduction in intestinal tissue lysates taken from IL-10-deficient mice compared to the wild-type controls.…”

“…Interleukin-10 is considered a classical anti-inflammatory cytokine that downregulates pro-inflammatory pathways, including activation of NF κ B in immune cells such as macrophages and dendritic cells [ 29 ]. We recently showed that epithelium-derived IL-10 appears to be a positive regulator of NF κ B in vitro, supporting its role as a major regulator of intestinal homeostasis [ 24 ]. Here, in the current study, we utilized IL-10-deficient mice to evaluate further the role of IL-10 within the intestinal epithelium in a TNF-induced in vivo model of inflammation that impacts on intestinal homeostasis [ 30 , 31 ].…”

“…NFκB activation is also essential for maintenance of intestinal barrier integrity, through regulation of cellular proliferation, differentiation, and survival, and the mediation of signaling and interaction between the mucosal immune system and the resident gut microbiota [ 23 ]. Recent work from our own lab, utilising murine small intestine crypt stem-cell-derived 3D enteroid cultures, has demonstrated that NFκB activation is the predominant signal pathway response seen within the first hour following exposure to TNF [ 24 ]. We were also able to demonstrate that enteroids deficient in IL-10 show a defective activation of NFκB, with dysregulated gene expression of known downstream targets of NFκB, such as Tnf , and NFκB pathway inhibitor genes Nfkbia and Tnfaip3 , encoding IκBα and A20 (tumor necrosis factor, alpha-induced protein 3, TNFAIP3), respectively [ 24 ].…”

“…Recent work from our own lab, utilising murine small intestine crypt stem-cell-derived 3D enteroid cultures, has demonstrated that NFκB activation is the predominant signal pathway response seen within the first hour following exposure to TNF [ 24 ]. We were also able to demonstrate that enteroids deficient in IL-10 show a defective activation of NFκB, with dysregulated gene expression of known downstream targets of NFκB, such as Tnf , and NFκB pathway inhibitor genes Nfkbia and Tnfaip3 , encoding IκBα and A20 (tumor necrosis factor, alpha-induced protein 3, TNFAIP3), respectively [ 24 ]. Although our previous data clearly demonstrated that endogenous IL-10 may act as a positive regulator of the canonical NFκB pathway in vitro, we looked to provide further supporting evidence using a whole animal approach.…”

Interleukin-10 is not associated with obstructive sleep apnea hypopnea syndrome: a systematic review and Meta-analysis

“…In addition, nocturnal hypercapnia and sleep fragmentation in patients with OSA also results in the activation of pro-in ammatory pathways and the down-regulation of anti-in ammatory proteins [11]. IL-10 is a pleiotropic cytokine mainly secreted by Th2 helper cells, which can widely inhibit the body's in ammatory response [14]. Gozal, et al [11] demonstrated that the circulating IL-10 levels in children with OSA was lower than that of the control group.…”