Background: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor... Show moreBackground: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Although IL-17A/F and TNF-alpha are known to functionally cooperate to exacerbate airway inflammation, proteins altered by their interaction in the lungs are not fully elucidated. Results: We used Slow Off-rate Modified Aptamer-based proteomic array to identify proteins that are uniquely and/or synergistically enhanced by concurrent stimulation with IL-17A/F and TNF-alpha in human bronchial epithelial cells (HBEC). The abundance of 38 proteins was significantly enhanced by the combination of IL-17A/F and TNF-alpha, compared to either cytokine alone. Four out of seven proteins that were increased > 2-fold were those that promote neutrophil migration; host defence peptides (HDP; Lipocalin-2 (LCN-2) and Elafin) and chemokines (IL-8, GRO alpha). We independently confirmed the synergistic increase of these four proteins by western blots and ELISA. We also functionally confirmed that factors secreted by HBEC stimulated with the combination of IL-17A/F and TNF-alpha uniquely enhances neutrophil migration. We further showed that PI3K and PKC pathways selectively control IL-17A/F + TNF-alpha-mediated synergistic production of HDPs LCN-2 and Elafin, but not chemokines IL-8 and GRO alpha. Using a murine model of airway inflammation, we demonstrated enhancement of IL-17A/F, TNF-alpha, LCN-2 and neutrophil chemokine KC in the lungs, thus corroborating our findings in-vivo. Conclusion: This study identifies proteins and signaling mediated by concurrent IL-17A/F and TNF-alpha exposure in the lungs, relevant to respiratory diseases characterized by chronic inflammation, especially neutrophilic airway inflammation such as severe asthma. Show less
Altieri, A.; Piyadasa, H.; Hemshekhar, M.; Osawa, N.; Recksiedler, B.; Spicer, V.; ... ; Mookherjee, N. 2022
Background: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor... Show moreBackground: The heterodimer interleukin (IL)-17A/F is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Although IL-17A/F and TNF-alpha are known to functionally cooperate to exacerbate airway inflammation, proteins altered by their interaction in the lungs are not fully elucidated.Results: We used Slow Off-rate Modified Aptamer-based proteomic array to identify proteins that are uniquely and/or synergistically enhanced by concurrent stimulation with IL-17A/F and TNF-alpha in human bronchial epithelial cells (HBEC). The abundance of 38 proteins was significantly enhanced by the combination of IL-17A/F and TNF-alpha, compared to either cytokine alone. Four out of seven proteins that were increased > 2-fold were those that promote neutrophil migration; host defence peptides (HDP; Lipocalin-2 (LCN-2) and Elafin) and chemokines (IL-8, GRO alpha). We independently confirmed the synergistic increase of these four proteins by western blots and ELISA. We also functionally confirmed that factors secreted by HBEC stimulated with the combination of IL-17A/F and TNF-alpha uniquely enhances neutrophil migration. We further showed that PI3K and PKC pathways selectively control IL-17A/F + TNF-alpha-mediated synergistic production of HDPs LCN-2 and Elafin, but not chemokines IL-8 and GRO alpha. Using a murine model of airway inflammation, we demonstrated enhancement of IL-17A/F, TNF-alpha, LCN-2 and neutrophil chemokine KC in the lungs, thus corroborating our findings in-vivo.Conclusion: This study identifies proteins and signaling mediated by concurrent IL-17A/F and TNF-alpha exposure in the lungs, relevant to respiratory diseases characterized by chronic inflammation, especially neutrophilic airway inflammation such as severe asthma. Show less
Vitamin D plays an active role in the modulation of innate and adaptive immune responses as well as in the protection against respiratory pathogens, e.g. by increasing expression of the... Show moreVitamin D plays an active role in the modulation of innate and adaptive immune responses as well as in the protection against respiratory pathogens, e.g. by increasing expression of the antimicrobial peptide hCAP18/LL-37. The main aim of this thesis was to elucidate the role of inflammation on the protective effects of vitamin D on respiratory host defense responses in chronic inflammatory lung diseases such as chronic obstructive pulmonary disease (COPD). Airway epithelial host defense responses in COPD patients are defective and these patients are therefore more susceptible to respiratory infections. In this thesis we have shown that exposure to cigarette smoke, a main risk factor for COPD, reduced expression of certain host defense mediators by affecting end-stage airway epithelial differentiation and might explains why COPD patients are more susceptible to respiratory infections. We have further demonstrated in the studies presented in this thesis that certain airway inflammatory mediators could possibly interfere with vitamin D metabolism by promoting expression of vitamin D degrading enzyme CYP24A1, thereby reducing local levels of vitamin D and accompanying protective antimicrobial and anti-inflammatory actions. These new insights may yield possible new strategies to target CYP24A1 that enhance local levels and signaling of vitamin D to increase protection against exacerbations in COPD patients. Show less
