https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42308 Camp^-/-) and exogenous cathelicidin prevented ICS-mediated expansion of streptococci within the microbiota and improved bacterial clearance. Suppression of pulmonary immunity by ICS was mediated by augmentation of the protease cathepsin D. Collectively, these data suggest a central role for cathepsin D/cathelicidin in the suppression of antibacterial host defense by ICS in COPD. Therapeutic restoration of cathelicidin to boost antibacterial immunity and beneficially modulate the lung microbiota might be an effective strategy in COPD.]]> Mon 22 Aug 2022 10:35:15 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46061 in vitro in human airway epithelial cell cultures and in vivo in mouse models of ICS administration. Mice deficient in the type I IFN-α/β receptor (Ifnar1^-/-) and administration of exogenous IFN-β were used to study the functional role of type-I interferon signaling in ACE2 expression. We compared sputum ACE2 expression in patients with COPD stratified according to use or nonuse of ICS. Results: ICS administration attenuated ACE2 expression in mice, an effect that was reversed by exogenous IFN-β administration, and Ifnar1^-/- mice had reduced ACE2 expression, indicating that type I interferon contributes mechanistically to this effect. ICS administration attenuated expression of ACE2 in airway epithelial cell cultures from patients with COPD and in mice with elastase-induced COPD-like changes. Compared with ICS nonusers, patients with COPD who were taking ICSs also had reduced sputum expression of ACE2. Conclusion: ICS therapies in COPD reduce expression of the SARS-CoV-2 entry receptor ACE2. This effect may thus contribute to altered susceptibility to COVID-19 in patients with COPD.]]> Fri 11 Nov 2022 14:22:05 AEDT ]]>