Background Rhinovirus infection is a major cause of asthma exacerbations. Objectives We studied nasal and bronchial mucosal inflammatory responses during experimental rhinovirus-induced asthma exacerbations. Methods We used nasosorption on days 0, 2–5 and 7 and bronchosorption at baseline and day 4 to sample mucosal lining fluid to investigate airway mucosal responses to rhinovirus infection in patients with allergic asthma (n=28) and healthy non-atopic controls (n=11), by using a synthetic absorptive matrix and measuring levels of 34 cytokines and chemokines using a sensitive multiplex assay. Results Following rhinovirus infection asthmatics developed more upper and lower respiratory symptoms and lower peak expiratory flows compared to controls (all P<0.05). Asthmatics also developed higher nasal lining fluid levels of an anti-viral pathway (including IFN-γ, IFN-λ/IL-29, CXCL11/ITAC, CXCL10/IP10 and IL-15) and a type 2 inflammatory pathway (IL-4, IL-5, IL-13, CCL17/TARC, CCL11/eotaxin, CCL26/eotaxin-3) (area under curve day 0–7, all P<0.05). Nasal IL-5 and IL-13 were higher in asthmatics at day 0 (P<0.01) and levels increased by days 3 and 4 (P<0.01). A hierarchical correlation matrix of 24 nasal lining fluid cytokine and chemokine levels over 7days demonstrated expression of distinct interferon-related and type 2 pathways in asthmatics. In asthmatics IFN-γ, CXCL10/IP10, CXCL11/ITAC, IL-15 and IL-5 increased in bronchial lining fluid following viral infection (all P<0.05). Conclusions Precision sampling of mucosal lining fluid identifies robust interferon and type 2 responses in the upper and lower airways of asthmatics during an asthma exacerbation. Nasosorption and bronchosorption have potential to define asthma endotypes in stable disease and at exacerbation.

• A/J mice (males, 5 weeks old) were dosed with hydrocortisone (125 mg/kg, sc) on days 3, 2 and 1 before infection, and with cyclophosphamide (250 mg/kg, ip) 2 days before infection to induce temporary neutropenia. • On day 0, animals were infected intranasally with 30 μL of the spore suspension of Aspergillus fumigatus (ATCC 13073) at a concentration of 1.67 × 108 spores mL-1 of physiological saline. • PC945 was treated intranasally on days 1, 2 and 3 post infection and animals were culled 24 hours after the final treatment on day 3 (day 4). • Bronchoalveolar lavage fluid (BALF) and serum were collected for biomarker analysis. Bronchial epithelial lining fluid (ELF) was also collected using a synthetic absorptive matrix (NasosorptionTM SAM strips: http://www.huntdevelopments.co.uk). • Biomarkers were assessed in mice alive at day 4.

Carbon-fibre-reinforced polyether ether ketone (CFR-PEEK) exhibits excellent biomechanical properties as it has an elastic modulus similar to bone. However, CFR-PEEK displays inferior biocompatibility compared with titanium alloy and coating techniques are therefore of interest in order to improve integration. In this paper, the early biological response to CFR-PEEK implants, with and without hydroxyapatite coating, was investigated. Furthermore, a hydroxyapatite-coated titanium alloy reference served as a clinically relevant control. The study was conducted in a rabbit model, both in femur trabecular bone as well as in tibia cortical bone. The results demonstrated that an hydroxyapatite coating significantly enhances the bone response to PEEK implants in vivo. Moreover, in cortical bone, hydroxyapatite-coated PEEK implants induced superior bone response compared with hydroxyapatite-coated Ti ones. These results suggest that hydroxyapatite-coated CFR-PEEK is a suitable material for in vivo implantation.

RATIONALERhinoviruses are the major cause of asthma exacerbations; however, its underlying mechanisms are poorly understood. We hypothesized that the epithelial cell-derived cytokine IL-33 plays a central role in exacerbation pathogenesis through augmentation of type 2 inflammation.OBJECTIVESTo assess whether rhinovirus induces a type 2 inflammatory response in asthma in vivo and to define a role for IL-33 in this pathway.METHODSWe used a human experimental model of rhinovirus infection and novel airway sampling techniques to measure IL-4, IL-5, IL-13, and IL-33 levels in the asthmatic and healthy airways during a rhinovirus infection. Additionally, we cultured human T cells and type 2 innate lymphoid cells (ILC2s) with the supernatants of rhinovirus-infected bronchial epithelial cells (BECs) to assess type 2 cytokine production in the presence or absence of IL-33 receptor blockade.MEASUREMENTS AND MAIN RESULTSIL-4, IL-5, IL-13, and IL-33 are all induced by rhinovirus in the asthmatic airway in vivo and relate to exacerbation severity. Further, induction of IL-33 correlates with viral load and IL-5 and IL-13 levels. Rhinovirus infection of human primary BECs induced IL-33, and culture of human T cells and ILC2s with supernatants of rhinovirus-infected BECs strongly induced type 2 cytokines. This induction was entirely dependent on IL-33.CONCLUSIONSIL-33 and type 2 cytokines are induced during a rhinovirus-induced asthma exacerbation in vivo. Virus-induced IL-33 and IL-33-responsive T cells and ILC2s are key mechanistic links between viral infection and exacerbation of asthma. IL-33 inhibition is a novel therapeutic approach for asthma exacerbations.

Asthma is a heterogeneous condition and it is vital to accurately predict responders to targeted therapies. However, difficulties in measuring IL5 and IL13 have forced reliance on indirect markers of Th2 inflammation with limited success. Using the human model of experimental rhinovirus (RV) induced asthma exacerbation (AE) and new techniques to absorb nasal (nasosorption) and bronchial (bronchosorption) mucosal lining fluid (MLF), we explored Th2 inflammation during a RV-induced AE. Methods: 32 mild-to-moderate asthmatics and 14 healthy subjects were inoculated with RV-16. Bronchoscopies were performed 2 weeks prior to inoculation and on d4 post-inoculation. Cytokines were measured in both bronchial and nasal samples at baseline and on d4 with further nasal sampling on days 2,3,5,7,10 and 42. Results: Nasal IL5 and IL13 were significantly increased in asthma during infection compared to baseline (p Conclusion: RV induced Th2 inflammation correlated with AE severity. Nasal Th2 inflammation correlated with bronchial levels whilst baseline Th2 levels predicted the magnitude of Th2 induction during the AE. Nasosorption is a non-invasive, rapid technique capable of measuring Th2 inflammation directly. It may be possible to use this technique as a biomarker to guide therapy with anti-IL5 and anti-IL13 mAb treatments.