RT Journal Article
SR Electronic
T1 Higher expression of lipoxygenase and cyclooxygenase pathways in bronchial than alveolar lavage from allergic asthmatics
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP PA3118
DO 10.1183/13993003.congress-2021.PA3118
VO 58
IS suppl 65
A1 Nicole van der Burg
A1 Henning Stenberg
A1 Zuzanna Diamant
A1 Leif Bjermer
A1 Ellen Tufvesson
YR 2021
UL http://erj.ersjournals.com/content/58/suppl_65/PA3118.abstract
AB The lipoxygenase and cyclooxygenase pathways are involved in airway inflammation and remodelling in asthma. Previously we showed that downstream factors of the lipoxygenase pathway are more abundant in the central than in peripheral airways. Therefore, we aimed to assess the mRNA expression of upstream factors of both pathways in cells from bronchial and alveolar lavage. Allergic asthmatics undertook a bronchial allergen challenge, 9 patients had an early allergic reaction (EAR) and 6 patients also had a late allergic reaction (EAR+LAR). Bronchial and alveolar lavages were sampled at baseline and 24 h post allergen challenge. mRNA expression of 5-LO, FLAP, LTA4h and LTC4s in the lipoxygenase pathway and COX-1, COX-2, PGD2s and PTGEs2 in the cyclooxygenase pathway were analysed (relative to GAPDH) in the lavage cells. At baseline, LTA4h (p=0.008), LTC4s (p=0.03) and PGD2s (p=0.03) were significantly higher in the bronchial than the alveolar lavage cells. The higher bronchial expression seen in the LTC4s was only observed in the EAR+LAR group. At 24 h post challenge, FLAP (p=0.04), LTA4h (p=0.02), COX-2 (p=0.01) and PGD2s (p=0.02) were significantly higher in the bronchial lavage cells. Overall, all genes (except PTGEs2) tended to be expressed higher in the bronchial than the alveolar lavage cells. In addition, higher PGD2s expression post challenge correlated with increased need for rescue medication (ACT, Q4 prior to the challenge) (p=0.009, r=-0.8). As these pathways are highly expressed in the bronchial lumen cells of allergic asthmatics, further investigation is needed to confirm this is reflected in the tissue before central airway targeting is proposed.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3118.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).