RNA-sequencing analysis of lung primary fibroblast response to eosinophil-degranulation products predicts downstream effects on inflammation, tissue remodeling and lipid metabolism

Abstract

BackgroundThe association of eosinophils with inflammation and tissue remodeling is at least partially due to their release of toxic granule proteins and other mediators, including cytokines. Tissue remodeling and consequent functional defects are affected by activity of connective tissue fibroblasts. Exaggerated fibroblast activation, accumulation and change of phenotype may lead to fibrosis and loss of tissue function. So far, little information has been reported on how eosinophils affect inflammation and tissue remodeling via the activation of fibroblasts. We have recently shown that eosinophil activation with IL-3 led to a robust eosinophil degranulation on immunoglobin-G (IgG) coated plates. Thus, in the present study, we analyze the effects of IL-3-activated eosinophil degranulation products on primary human lung fibroblasts (HLF) using whole transcriptome sequencing.MethodsConditioned media was obtained from eosinophils that were pre-activated with IL-3 or IL-5 and subsequently cultured for 6 h on IgG to induce degranulation. This conditioned media was added on human lung fibroblasts (HLF) for 24 h and the cell lysates were then subjected to whole transcriptome sequencing to identify global changes in gene expression. Differentially expressed genes were analyzed using the Ingenuity Pathway Analysis (IPA), and validated by qPCR.ResultsIn HLF, the expression level of 300 genes was changed by conditioned media from IL-3-activated eosinophils compared to control fibroblast cultures. Among these 300 genes, the expression level of 35 genes coding for known proteins was upregulated by IL-3- versus IL-5-pre-activated eosinophils. Of the 35 upregulated genes, IPA identified C3, CH25H, CXCL1, CXCL8, CYP1A1, ICAM1, IL6 and UCN2 as having downstream functions on inflammation, tissue remodeling and lipid synthesis. This analysis combined with previous RNA sequencing analyses of eosinophils suggest IL-1ß, OSM and TNFSF12 as potential upstream regulators of fibroblasts.ConclusionsThis study has identified several novel pro-inflammatory and pro–remodeling mediators produced by fibroblasts in response to activated eosinophils. These findings may have significant implications on the role of eosinophil/fibroblast interactions in eosinophilic disorders.Electronic supplementary materialThe online version of this article (10.1186/s12931-017-0669-8) contains supplementary material, which is available to authorized users.

Eosinophil cytolysis on Immunoglobulin G is associated with microtubule formation and suppression of rho‐associated protein kinase signalling

“…In this model also, neutralizing antibodies against either CD32 or αMß2 integrin totally blocked eosinophil attachment and degranulation (EDN release) on heat‐aggregated (HA)‐IgG . In contrast to IL3, short‐ or long‐term treatment with IL5 does not result in a similar phenotypic shift and results in rapid loss of surface IL5 receptor and downstream signalling . Notably, antigen‐bound or aggregated IgG is a relevant activator of eosinophils, because IgG is present in human airways, and allergen‐specific IgG correlates with EDN levels in sputum of asthmatic patients, and IgG complexed with eosinophil peroxidase (EPX) and other autologous cellular components is present in airways of asthma subjects .…”

“…Notably, antigen‐bound or aggregated IgG is a relevant activator of eosinophils, because IgG is present in human airways, and allergen‐specific IgG correlates with EDN levels in sputum of asthmatic patients, and IgG complexed with eosinophil peroxidase (EPX) and other autologous cellular components is present in airways of asthma subjects . Importantly, we have observed that the interaction of in vitro‐IL3‐primed blood and in vivo‐primed airway eosinophils with HA‐IgG leads to an apparent cell death by cytolysis . Therefore, in this study, we sought to determine the key intracellular events implicated in the cytolytic death of IL3‐primed eosinophils plated on HA‐IgG.…”

21st Century Tools for Nanotoxicology: Transcriptomic Biomarker Panel and Precision‐Cut Lung Slice Organ Mimic System for the Assessment of Nanomaterial‐Induced Lung Fibrosis

“…[75] The expression of cholesterol 25 hydroxylase (CH25H) is upregulated in human lung primary fibroblasts following stimulation with eosinophils. [76] Several studies have shown detectable level of cathepsin S (Ctss) in the airways of patients with cystic fibrosis. [77] Thus, many of the genes from PFS17 are associated with lung fibrosis disease in humans.…”

Prediction of Overall Survival for Early-stage Non-small Cell Lung Cancer via a Novel 7-gene Prognostic Signature and Allele Frequency Deviation (AFD)

“…Where there are no previous reports related to the prognosis of cancer outcomes in patients. Stephane Esnault, et al [68] reported that ucn2 had the downstream function of inflammation, tissue remodeling, and lipid synthesis in human lung fibroblasts(HLFs). Where no previous survival prediction reports have been reported for cancer patients.…”