https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15983 50% of asthma-related healthcare costs. New investigations into the pathogenesis of glucocorticoid resistance in severe asthma indicate that pulmonary macrophages may play central roles in promoting airway inflammation, particularly in asthma that is resistant to steroid therapy. Importantly, factors that are linked to the activation of pulmonary macrophages may contribute to glucocorticoid resistance and severe asthma. Here, we review recent advances in understanding the roles of pulmonary macrophages in the mechanisms of glucocorticoid resistance and the pathogenesis of severe asthma. We discuss the role of macrophage phenotype, infection, IFN-γ, LPS, associated signaling pathways, TNF-α, MIF, and other macrophage-associated factors. Understanding the pathogenesis of steroid-resistant severe asthma will contribute to the identification of optimal therapeutic strategies for the effective management of the disease.]]> Sat 24 Mar 2018 08:23:36 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38228 Haemophilus influenzae (NTHi) infection drives the development of steroid-resistant allergic airway disease (SRAAD), exacerbates clinical symptoms, worsens quality of life, and accounts for most of the related healthcare burden. The poor understanding of the pathogenesis of SRAAD deters the development of more effective therapeutic strategies. Here, we established a murine model of NTHi infection-induced exacerbation of allergic airway disease. We showed that NTHi infection drove Th 17-mediated pulmonary neutrophilic inflammation, aggravated airway hyper-responsiveness, and upset the balance of MUC5AC and MUC5B expression. Dexamethasone treatment effectively inhibited the features of allergic airway disease but failed to reduce NTHi-induced exacerbation, which was associated with the hyper-phosphorylation of p38 mitogen-activated protein kinase (MAPK). Interestingly, inhibition of p38 using a specific inhibitor (SB203580) only partly suppressed the airway hyper-responsiveness and mucus hyper-secretion but failed to abrogate the infection-induced neutrophilic inflammatory response in SRAAD. However, SB203580 and dexamethasone co-treatment substantially suppressed all the features of NTHi-induced SRAAD. Our findings highlight the importance of p38 MAPK in the pathogenesis of NTHi-induced steroid resistance, and this combined treatment approach may be a novel strategy against steroid-resistant asthma.]]> Mon 16 Aug 2021 16:15:47 AEST ]]>