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Jennifer Cane,1,2 Laura Tregidgo,1 Samantha Thulborn,1,2 Donna Finch,3 Mona Bafadhel1,2 1Respiratory Medicine Unit, Nuffield Department of Medicine, University of Oxford, Oxford, UK; 2Oxford NIHR Biomedical Research Centre, University of Oxford, Oxford, UK; 3Alchemab Therapeutics, Cambridge, UKCorrespondence: Jennifer Cane Email Jennifer.cane@ndm.ox.ac.ukBackground: Chronic obstructive pulmonary disease (COPD) and asthma have heterogeneous inflammation with inhaled corticosteroids (ICS) as a mainstay of treatment. There is increased prevalence of non-typeable Haemophilus influenzae (NTHi) persistence in airways of patients with neutrophilic airway inflammation, potentially due to suppressed host defence after corticosteroid treatment. Antimicrobial peptides (AMPs) have antimicrobial activity against pathogens and immunomodulatory effects. We investigated whether AMPs associate with NTHi presence in COPD and asthma, and whether ICS alter this.Methods: Secretory leukocyte protease inhibitor (SLPI), osteopontin, elafin and beta defensin-1 were measured in sputum supernatants from healthy donors (n=9), asthmatics (n=21) and patients with COPD (n=14). Elafin and beta defensin-1 were measured in a primary human bronchial epithelial cells (HBECs) from healthy and COPD donors infected with NTHi and pre-treated with fluticasone propionate (FP) and budesonide (BUD). Internalised NTHi was quantified by qPCR.Results: Sputum SLPI was negatively correlated with FEV1 (p< 0.001, r=− 0.610), FEV1% predicted (p< 0.001, r=− 0.583) and FEV1/FVC (p=0.001, r=− 0.528). Sputum beta defensin-1 was negatively associated with FEV1 (p< 0.001***r=− 0.594). SLPI and beta defensin-1 levels in sputum were higher in the healthy controls and COPD group compared to the asthma group (p=0.001 and p=0.014) and (p< 0.001 and p=0.007, respectively). ICS use was associated with higher sputum osteopontin compared to those with no ICS use. NTHi infection of COPD HBECs produced higher levels of beta defensin-1 compared to healthy donors (mean (SD) release: 45.1pg/mL (7.3) vs 21.2pg/mL (7.3) respectively, p=0.014). Elafin release from HBECs from COPD donors did not change following NTHi infection; however, elafin from healthy donors was significantly reduced (%mean reduction: 23.7%, 95% confidence intervals (CI) of reduction: 5.3– 38.4%, p< 0.01).Conclusion: Sputum SLPI and beta defensin-1 may be markers to identify those patients with declining lung function. ICS use was associated with higher sputum osteopontin compared to those with no ICS use.Keywords: antimicrobial peptide, non-typeable haemophilus influenzae, chronic obstructive pulmonary disease

Interleukin-1 inhibitors were tested in large arthritis trials with less than impressive results, despite having convincing disease expression data and pre-clinical animal model supporting the potential pathogenic role of this cytokine in these settings. Despite disappointing beginnings, some IL-1 pathway blocking drugs are now beginning to find a place in the pharmacopoeia of rheumatologists. Drug developers utilised rapidly growing understanding of the molecular pathway and the genetic basis of key diseases to seek out conditions in which IL-1 pathway activation was much more likely to have a pivotal role in disease pathogenesis compared to the major arthritides. This review details the crucial advances in understanding of the IL-1 pathway activation which enabled this progress, particularly the advent of inflammasome biology. The drug development of IL-1 biologics in rheumatological diseases makes a fascinating case study illustrating major changes in drug development strategy encompassing closer synergies between translational biology, underlying molecular pathophysiology of disease, and novel clinical development pathways of biologic therapeutics.

Disease association studies suggest that the cytokines IL1 and IL18 play a role in exacerbations of Chronic Obstructive Pulmonary Disease. A classical role of IL18 is to stimulate NK and T-Cells to produce IFNγ, a cytokine associated with viral exacerbations of COPD. IL1β, which is processed by the same mechanism as IL18, can have a similar effect on IFNγ. We sought to understand their respective role in IFNγ secretion in situations where they both could be released. Treatment of PBMCs with IL18 or IL1β (in the presence of IL12) was able to induce IFNγ release. This response was most sensitive to IL1β but IL18 was able to stimulate a greater maximal response. When LPS was used as a trigger of IFNγ release, a large amount of IL1β (11ng/mL) and a low amount of IL18 (27pg/mL) could be detected in the supernatant. Co-incubation with an IL18 neutralizing antibody, or the IL1 receptor antagonist anakinra, was able to inhibit the IFNγ response by 50% in both cases. In a second system, relevant to COPD exacerbations, the infection of bronchial epithelial cells with a human Rhinovirus induced the release of both IL18 (2.5ng/mL) and IL1β (435pg/mL). Transfer of the supernatant to PBMCs or NK cells induced IFNγ production which was largely IL1-dependent; inhibition of IL18 only had a small effect on IFNγ. This data showed that while they could induce IFNγ following an inflammatory stimulus, it is the context of their release that defines a predominant role for either IL18 or IL1β.

ObjectivesAn interferon (IFN) gene signature (IGS) is present in approximately 50% of early, treatment naive rheumatoid arthritis (eRA) patients where it has been shown to negatively impact initial response to treatment. We wished to validate this effect and explore potential mechanisms of action.MethodsIn a multicentre inception cohort of eRA patients (n=191), we examined the whole blood IGS (MxA, IFI44L, OAS1, IFI6, ISG15) with reference to circulating IFN proteins, clinical outcomes and epigenetic influences on circulating CD19+ B and CD4+ T lymphocytes.ResultsWe reproduced our previous findings demonstrating a raised baseline IGS. We additionally showed, for the first time, that the IGS in eRA reflects circulating IFN-α protein. Paired longitudinal analysis demonstrated a significant reduction between baseline and 6-month IGS and IFN-α levels (pPARP9, STAT1,andEPSTI1, associated with baseline IGS/IFNα levels. Differentially methylated CPG sites implicated altered transcription factor binding in B cells (GATA3, ETSI, NFATC2, EZH2) and T cells (p300, HIF1α).ConclusionsOur data suggest that, in eRA, IFN-α can cause a sustained, epigenetically mediated, pathogenic increase in lymphocyte activation and proliferation, and that the IGS is, therefore, a robust prognostic biomarker. Its persistent harmful effects provide a rationale for the initial therapeutic targeting of IFN-α in selected patients with eRA.