Key Points Neutrophil lifespan is extended in patients with gain-of-function HIF2A mutations. HIF-2α regulates in vivo neutrophil longevity and thus tissue inflammation and repair.

Key Points• We demonstrate an important role for NR4A receptors in regulating neutrophil lifespan and homeostasis in vitro and in vivo.• These findings may define targets for therapies for diseases driven by defects in neutrophil number and/or survival.The lifespan of neutrophils is plastic and highly responsive to factors that regulate cellular survival. Defects in neutrophil number and survival are common to both hematologic disorders and chronic inflammatory diseases. At sites of inflammation, neutrophils respond to multiple signals that activate protein kinase A (PKA) signaling, which positively regulates neutrophil survival. The aim of this study was to define transcriptional responses to PKA activation and to delineate the roles of these factors in neutrophil function and survival. In human neutrophil gene array studies, we show that PKA activation upregulates a significant number of apoptosis-related genes, the most highly regulated of these being NR4A2 and NR4A3. Direct PKA activation by the siteselective PKA agonist pair N6/8-AHA (8-AHA-cAMP and N6-MB-cAMP) and treatment with endogenous activators of PKA, including adenosine and prostaglandin E2, results in a profound delay of neutrophil apoptosis and concomitant upregulation of NR4A2/3 in a PKA-dependent manner. NR4A3 expression is also increased at sites of neutrophilic inflammation in a human model of intradermal inflammation. PKA activation also promotes survival of murine neutrophil progenitor cells, and small interfering RNA to NR4A2 decreases neutrophil production in this model. Antisense knockdown of NR4A2 and NR4A3 homologs in zebrafish larvae significantly reduces the absolute neutrophil number without affecting cellular migration. In summary, we show that NR4A2 and NR4A3 are components of a downstream transcriptional response to PKA activation in the neutrophil, and that they positively regulate neutrophil survival and homeostasis.

This study examined the establishment of neutrophilic inflammation in humans. We tested the hypotheses that neutrophil recruitment was associated with local CXCL8 production and that neutrophils themselves might contribute to the regulation of the size of the inflammatory response. Humans were challenged i.d. with endotoxin. Biopsies of these sites were examined for cytokine production and leukocyte recruitment by qPCR and IHC. Additional in vitro models of inflammation examined the ability of neutrophils to produce and sequester cytokines relevant to neutrophilic inflammation. i.d. challenge with 15 ng of a TLR4-selective endotoxin caused a local inflammatory response, in which 1% of the total biopsy area stained positive for neutrophils at 6 h, correlating with 100-fold up-regulation in local CXCL8 mRNA generation. Neutrophils themselves were the major source of the early cytokine IL-1β. In vitro, neutrophils mediated CXCL8 but not IL-1β clearance (>90% clearance of ≤2 nM CXCL8 over 24 h). CXCL8 clearance was at least partially receptor-dependent and modified by inflammatory context, preserved in models of viral infection but reduced in models of bacterial infection. In conclusion, in a human inflammatory model, neutrophils are rapidly recruited and may regulate the size and outcome of the inflammatory response through the uptake and release of cytokines and chemokines in patterns dependent on the underlying inflammatory stimulus.

Neutrophilic inflammation with prolonged neutrophil survival is common to many inflammatory conditions, including chronic obstructive pulmonary disease (COPD). There are few specific therapies that reverse neutrophilic inflammation, but uncovering mechanisms regulating neutrophil survival is likely to identify novel therapeutic targets. Screening of 367 kinase inhibitors in human neutrophils and a zebrafish tail fin injury model identified ErbBs as common targets of compounds that accelerated inflammation resolution. The ErbB inhibitors gefitinib, CP-724714, erbstatin and tyrphostin AG825 significantly accelerated apoptosis of human neutrophils, including neutrophils from people with COPD. Neutrophil apoptosis was also increased in Tyrphostin AG825 treated-zebrafish in vivo. Tyrphostin AG825 decreased peritoneal inflammation in zymosan-treated mice, and increased lung neutrophil apoptosis and macrophage efferocytosis in a murine acute lung injury model. Tyrphostin AG825 and knockdown of egfra and erbb2 by CRISPR/Cas9 reduced inflammation in zebrafish. Our work shows that inhibitors of ErbB kinases have therapeutic potential in neutrophilic inflammatory disease.

CCL2 is an important inflammatory chemokine involved in monocyte recruitment to inflamed tissues. The extracellular nucleotide signalling molecules UTP and ATP acting via the P2Y2 receptor are known to induce CCL2 secretion in macrophages. We confirmed this in the human THP-1 monocytic cell line showing that UTP is as efficient as LPS at inducing CCL2 at early time points (2–6 hours). Expression and calcium mobilisation experiments confirmed the presence of functional P2Y2 receptors on THP-1 cells. UTP stimulation of human peripheral CD14+ monocytes showed low responses to LPS (4-hour stimulation) but a significant increase above background following 6 hours of treatment. The response to UTP in human monocytes was variable and required stimulation >6 hours. With such variability in response we looked for single nucleotide polymorphisms in P2RY2 that could affect the functional response. Sequencing of P2RY2 from THP-1 cells revealed the presence of a single nucleotide polymorphism altering amino acid 312 from arginine to serine (rs3741156). This polymorphism is relatively common at a frequency of 0.276 (n = 404 subjects). Finally, we investigated CCL2 secretion in response to LPS or UTP in human macrophages expressing 312Arg-P2Y2 or 312Ser-P2Y2 where only the latter exhibited significant UTP-induced CCL2 secretion (n = 5 donors per group).

Following the EU Referendum, this paper tracks how pro-Remain British migrants living in other EU Member States expressed a sense of shame and dislocation in relation to their national identity. Developed from a survey of 909 British nationals living in other EU Member States, it hopes to make a timely intervention into wider debates about privileged migration, Britishness, citizenship and belonging.First, it outlines a new articulation of the "bad Britain" discourse among emigrants, who saw the UK as increasingly characterised by xenophobia and insularity. Second, it seeks to understand how their national identity and sense of belonging was being renegotiated post-referendum through a lens attentive to the cultural politics of emotion and innocence as an operation of whiteness.The Guardian's (2017) short video "British 'expats' in Spain count the Costa Brexit" starts with a shot of a sun-drenched, precisely levelled bowling green, its later-life occupants dressed in uniform white trousers and red t-shirts. 1 "What is the difference ... between an expat and a foreigner?" opens the narrator. "Well first of all, expats are British. A foreigner is probably someone living from another country living in Britain. They become foreigners. The British are never foreigners wherever they go!" is the provocative response of her first interviewee. Jolly muzak plays over sweeping shots of beaches and what are presumably British residents of Orihuela Costa, Alicante, described as "effectively a British enclave." Whether imperial retirees living in "expat" bubbles or mass-tourist style, sun-burnt hedonists, this video illustrates some of the common stereotypes of "Brits abroad," both of whom are classed and tend to fall somewhere on the right of the political spectrum (King et al., 2000;O'Reilly, 2000). The stock image of "Brits abroad," easily available through a Google image search, usually reflects one or other of these sat in pubs and draped in the Union Jack flag. This paper means to challenge and complicate these stereotypes.The paper makes two contributions. First, it outlines a new articulation of the "bad Britain" discourse following the referendum, which attributes the decline of Britain to its increasing insularity and xenophobia. Second, through an analysis attentive to the relationship between emotions, nationality and whiteness, it examines the role of innocence as an operation of whiteness in respondents' widespread expressions of shame and loss following the EU referendum result (Emejulu, 2016).Although British emigrants are certainly not the most vulnerable nor the largest group to be impacted by this process, at an estimated 900,000 (Office of National Statistics, 2017), their number and new-found circumstances do call for attention, and offer interesting insights into privileged mobilities and shifting landscapes of belonging, citizenship and Britishness. Developed from a survey of 909 British nationals living in continental Europe and undertaken around the one-year -

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