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The delivery of RNA across biological barriers can be achieved by encapsulation in lipid nanoparticles (LNPs). Cationic amphiphilic drugs (CADs) are pharmacologically diverse compounds with ionizable lipid-like features. In this work, we applied CADs as a fifth component of state-of-the-art LNPs via microfluidic mixing. Improved cytosolic delivery of both siRNA and mRNA was achieved by partly replacing the cholesterol fraction of LNPs with CADs. The LNPs could cross the mucus layer in a mucus-producing air-liquid interface model of human primary bronchial epithelial cells following nebulization. Moreover, CAD-LNPs demonstrated improved epithelial and endothelial targeting following intranasal administration in mice, without a marked pro-inflammatory signature. Importantly, quantification of the CAD-LNP molar composition, as demonstrated for nortriptyline, revealed a gradual leakage of the CAD from the formulation during LNP dialysis. Altogether, these data suggest that the addition of a CAD prior to the rapid mixing process might have an impact on the composition, structure, and performance of LNPs.

Experimental studies suggest that neutrophils could contribute to allergic asthma pathogenesis, that is mainly driven by type 2 immunity. Inhalation of diesel exhaust particles (DEP) is implicated in both exacerbation and development of asthma. Since exposure to DEP is associated with a neutrophilic component, we aimed to investigate how exposure to the combination of allergens and DEP modulates neutrophilic responses. Human bronchial epithelial cells (HBEC) were exposed to house dust mite (HDM), DEP or HDM + DEP in vitro to determine the expression of neutrophil-recruiting chemokines. Female (C57BL/6 J) mice were intranasally instilled with saline, DEP, HDM or combined HDM + DEP for 3 weeks (subacute) or 6 weeks (chronic). The neutrophilic responses were determined in lung tissue and bronchoalveolar lavage fluid (BALF). Simultaneous exposure to HDM + DEP resulted in increased CXCL1 and CXCL8 mRNA expression by HBEC in vitro. In mice, subacute exposure to HDM + DEP induced a strong mixed eosinophilic/neutrophilic inflammation in BALF and lung and was associated with higher expression of neutrophil-attracting chemokines and NET formation compared to the sole exposures. After chronic HDM + DEP exposure, a similar neutrophilic response was observed, however the NET formation was less pronounced. Interestingly, the increase of BALF eosinophils was also significantly attenuated after chronic HDM + DEP exposure compared to the subacute exposure. Subacute and chronic HDM + DEP exposure induced goblet cell hyperplasia and airway hyperresponsiveness. Our data suggest a role for neutrophils and NETs in pollutant-aggravated eosinophilic allergic asthma. Moreover, subacute exposure to HDM + DEP induces a mixed eosinophilic/neutrophilic response whereas upon chronic HDM + DEP exposure there is a shift in inflammatory response with a more prominent neutrophilic component., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The Department of Respiratory Medicine (Ghent University) was funded by Scientific Research in Flanders (FWO Vlaanderen, FWO041819N and FWO-EOS projects G0G2318N, G0H1222N) and a Ghent University Grant (BOF/GOA 01G00819). TM holds a Chiesi Chair on the Role of Environmental factors in Asthma development and a GSK chair on eosinophilic airway disease., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Receptor-interacting protein kinase 1 (RIPK1) is a key mediator of regulated cell death (including apoptosis and necroptosis) and inflammation, both drivers of COPD pathogenesis. We aimed to define the contribution of RIPK1 kinase-dependent cell death and inflammation in the pathogenesis of COPD., Methods: We assessed RIPK1 expression in single-cell RNA sequencing (RNA-seq) data from human and mouse lungs, and validated RIPK1 levels in lung tissue of COPD patients via immunohistochemistry. Next, we assessed the consequences of genetic and pharmacological inhibition of RIPK1 kinase activity in experimental COPD, using Ripk1 S25D/S25D kinase-deficient mice and the RIPK1 kinase inhibitor GSK'547., Results: RIPK1 expression increased in alveolar type 1 (AT1), AT2, ciliated and neuroendocrine cells in human COPD. RIPK1 protein levels were significantly increased in airway epithelium of COPD patients compared with never-smokers and smokers without airflow limitation. In mice, exposure to cigarette smoke (CS) increased Ripk1 expression similarly in AT2 cells, and further in alveolar macrophages and T-cells. Genetic and/or pharmacological inhibition of RIPK1 kinase activity significantly attenuated airway inflammation upon acute and subacute CS exposure, as well as airway remodelling, emphysema, and apoptotic and necroptotic cell death upon chronic CS exposure. Similarly, pharmacological RIPK1 kinase inhibition significantly attenuated elastase-induced emphysema and lung function decline. Finally, RNA-seq on lung tissue of CS-exposed mice revealed downregulation of cell death and inflammatory pathways upon pharmacological RIPK1 kinase inhibition., Conclusions: RIPK1 kinase inhibition is protective in experimental models of COPD and may represent a novel promising therapeutic approach., Competing Interests: Conflict of interest: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The RIPK1 kinase inhibitor GSK′547 was a kind gift from A.M. Beal (GlaxoSmithKline) who approved the manuscript but was not involved in funding or designing the study. T. Maes reports grants from FWO Flanders, Chiesi and GlaxoSmithKline, and is a shareholder of Oryzon Genomics and Mendelion Lifesciences SL, outside the submitted work. G.F. Joos reports consulting fees from GlaxoSmithKline and AstraZeneca, lecture honoraria from GlaxoSmithKline, AstraZeneca, Novartis, Lapharcon and EURECA VZW, travel support from GlaxoSmithKline, and acts as chair of the operational Committee IRC (International Respiratory Coalition) for the European Respiratory Society, outside the submitted work. G.G. Brusselle reports advisory board participation and lecture honoraria from AstraZeneca, Boehringer Ingelheim, Chiesi, GlaxoSmithKline, Merch Sharp & Dohme, Novartis and Sanofi, outside the submitted work. P.M. Hansbro reports grants from the National Health and Medical Research Council (APP1138004, Defining the roles and targeting interferon-epsilon as a new therapy for influenza in asthma and COPD; and APP1179092, Development of a novel effective therapy for asthma and COPD), outside the submitted work., (Copyright ©The authors 2023. For reproduction rights and permissions contact permissions@ersnet.org.)

Objectives: Innate lymphoid cells (ILCs) secrete cytokines, such as IFN-γ, IL-13 and IL-17, which are linked to chronic obstructive pulmonary disease (COPD). Here, we investigated the role of pulmonary ILCs in COPD pathogenesis., Methods: Lung ILC subsets in COPD and control subjects were quantified using flow cytometry and associated with clinical parameters. Tissue localisation of ILC and T-cell subsets was determined by immunohistochemistry. Mice were exposed to air or cigarette smoke (CS) for 1, 4 or 24 weeks to investigate whether pulmonary ILC numbers and activation are altered and whether they contribute to CS-induced innate inflammatory responses., Results: Quantification of lung ILC subsets demonstrated that ILC1 frequency in the total ILC population was elevated in COPD and was associated with smoking and severity of respiratory symptoms (COPD Assessment Test [CAT] score). All three ILC subsets localised near lymphoid aggregates in COPD. In the COPD mouse model, CS exposure in C57BL/6J mice increased ILC numbers at all time points, with relative increases in ILC1 in bronchoalveolar lavage (BAL) fluid. Importantly, CS exposure induced increases in neutrophils, monocytes and dendritic cells that remained elevated in Rag2 / Il2rg -deficient mice that lack adaptive immune cells and ILCs. However, CS-induced CXCL1, IL-6, TNF-α and IFN-γ levels were reduced by ILC deficiency., Conclusion: The ILC1 subset is increased in COPD patients and correlates with smoking and severity of respiratory symptoms. ILCs also increase upon CS exposure in C57BL/6J mice. In the absence of adaptive immunity, ILCs contribute to CS-induced pro-inflammatory mediator release, but are redundant in CS-induced innate inflammation., Competing Interests: TM reports grants personal fees from GlaxoSmithKline, outside the submitted work; and is shareholder from Oryzon Genomics and Mendelion Lifesciences SL; and holds a Chiesi chair on Environmental factors in Asthma. GGB reports personal fees from Astra Zeneca, Boehringer Ingelheim, Chiesi, GlaxoSmithKline, Novartis, Sanofi and Teva, outside the submitted work. EEB, SP, EGDS, KCDG, HPVE, JDV, PMH, MB, MS, SW, FV, KRB and GFJ have no conflict of interest to declare., (© 2021 The Authors. Clinical & Translational Immunology published by John Wiley & Sons Australia, Ltd on behalf of Australian and New Zealand Society for Immunology, Inc.)

Suppression of airway inflammation with inhaled corticosteroids has been the key therapeutic approach for asthma for many years. Identification of inflammatory phenotypes in asthma has moreover led to important breakthroughs, e.g. with specific targeting of the IL-5 pathway as add-on treatment in difficult-to-treat eosinophilic asthma. However, the impact of interfering with the neutrophilic component in asthma is less documented and understood. This review provides an overview of established and recent insights with regard to the role of neutrophils in asthma, focusing on research in humans. We will describe the main drivers of neutrophilic responses in asthma, the heterogeneity in neutrophils and how they could contribute to asthma pathogenesis. Moreover we will describe findings from clinical trials, in which neutrophilic inflammation was targeted. It is clear that neutrophils are important actors in asthma development and play a role in exacerbations. However, more research is required to fully understand how modulation of neutrophil activity could lead to a significant benefit in asthma patients with airway neutrophilia., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To assess whether a robust typology of sex offenders could be established based on the patterns of denial displayed, a previously developed semistructured interview method was used to assess denial in a mixed group of convicted rapists and child molesters. Cluster analysis was used to establish homogeneous groups of sex offenders based on the pattern of denial in each case, with a three-cluster solution emerging as the most appropriate, confirming previous research. The denial groups were compared in relation to objective offense characteristics to assess whether a consistent typology of offenders emerged. Each of the four groups of offenders identified (three groups emerging from the cluster analysis and an "absolute denier" group) corresponded closely with the previously identified typology. However, the authors failed to replicate previously identified differences between the denial groups in relation to independent variables such as offense type. Each group contained both rapists and child molesters and was found to differ quantitatively rather than qualitatively in the pattern of the denial expressed, with attributional style being the most consistent form of denial present in all groups. The authors conclude that denial consists of at least two continuous dimensions, rather than being a dichotomous phenomenon. Differences in the patterns of denial displayed by rapists and child molesters were found to be primarily quantitative rather than qualitative.