Journal Article

RNA-Seq Reveals Activation of Both Common and Cytokine-Specific Pathways following Neutrophil Priming

Thomas, Huw B., Wright, Helen L., Edwards, Steven W., Moots, Robert J.

2013

Overview

Neutrophils are central to the pathology of inflammatory diseases, where they can damage host tissue through release of reactive oxygen metabolites and proteases, and drive inflammation via secretion of cytokines and chemokines. Many cytokines, such as those generated during inflammation, can induce a similar \"primed\" phenotype in neutrophils, but it is unknown if different cytokines utilise common or cytokine-specific pathways to induce these functional changes. Here, we describe the transcriptomic changes induced in control human neutrophils during priming in vitro with pro-inflammatory cytokines (TNF-α and GM-CSF) using RNA-seq. Priming led to the rapid expression of a common set of transcripts for cytokines, chemokines and cell surface receptors (CXCL1, CXCL2, IL1A, IL1B, IL1RA, ICAM1). However, 580 genes were differentially regulated by TNF-α and GM-CSF treatment, and of these 58 were directly implicated in the control of apoptosis. While these two cytokines both delayed apoptosis, they induced changes in expression of different pro- and anti-apoptotic genes. Bioinformatics analysis predicted that these genes were regulated via differential activation of transcription factors by TNF-α and GM-CSF and these predictions were confirmed using functional assays: inhibition of NF-κB signalling abrogated the protective effect of TNF-α (but not that of GM-CSF) on neutrophil apoptosis, whereas inhibition of JAK/STAT signalling abrogated the anti-apoptotic effect of GM-CSF, but not that of TNF-α (p<0.05). These data provide the first characterisation of the human neutrophil transcriptome following GM-CSF and TNF-α priming, and demonstrate the utility of this approach to define functional changes in neutrophils following cytokine exposure. This may provide an important, new approach to define the molecular properties of neutrophils after in vivo activation during inflammation.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Apoptosis / Bioinformatics / Biology / Cell activation / Cell surface / Chemokines / Chronic obstructive pulmonary disease / Cytokines / Cytokines - biosynthesis / Cytokines - immunology / Cytokines - pharmacology / Disease / DNA binding proteins / Female / Gene expression / Genes / Genomes / Granulocyte-macrophage colony-stimulating factor / Humans / Inflammation / Inflammation - immunology / Inflammation - metabolism / Inflammation - pathology / Inflammatory diseases / Inhibition / Intercellular adhesion molecule 1 / Intercellular Adhesion Molecule-1 - biosynthesis / Intercellular Adhesion Molecule-1 - immunology / Interleukin 1 / Interleukin 1 receptor antagonist / Janus Kinases - immunology / Janus Kinases - metabolism / Kinases / Leukocytes (neutrophilic) / Male / Medicine / Metabolites / Neutrophil Activation / Neutrophils / Neutrophils - immunology / Neutrophils - metabolism / Neutrophils - pathology / NF-κB protein / Oxygen / Pathways / Predictions / Priming / Proteases / Receptors / Rheumatoid arthritis / Ribonucleic acid / RNA / RNA sequencing / Signal Transduction / Signaling / STAT Transcription Factors - immunology / STAT Transcription Factors - metabolism / Transcription (Genetics) / Transcription activation / Transcription factors / Transcriptome - drug effects / Transcriptome - immunology / Tumor necrosis factor / Tumor necrosis factor-α