Background
The rate of allergic reactions to COVID-19 vaccines is greater among patients suffering from a history of high-risk allergies. Bronchospasm has been reported as an early reaction after COVID-19 vaccines in asthmatic patients.
Aim
To assess the impact of BNT162b2 on the airway contractility in human hyperresponsive airways.
Methods
Human isolated airways were passively sensitized overnight and then challenged 45 min with the platelet-activating factor (100 nM) to reproduce ex vivo the condition of airways of subjects suffering from severe eosinophilic asthma. Airways were mounted in an isolated organ bath system and contracted by electrical filed stimulation (EFS); concentration-responses curve to BNT162b2 were tested on airway contractility. Some experiments were performed by using BNT162b2 after mRNA denaturation.
Results
BNT162b2 1 ng/ml significantly increased the overall EFS-induced contractility (+13.3±2.2 vs. control, P<0.05). The maximal effect was detected for BNT162b2 100 ng/ml at EFS 25 Hz (+38.0±5.7 vs. control, P<0.001). EC50 was 1.2±1.24 ng/ml at EFS 3 Hz, 0.6±0.3 ng/ml at EFS 10 Hz, and 1.8±1.8 ng/ml at EFS 25 Hz. The increased contractility induced by BNT162b2 was not significantly reduced after mRNA denaturation.
Conclusions
These increased contractility induced by BNT162b2 was related to the excipients, since mRNA denaturation did not prevent hyperresponsiveness. This study supports the link between COVID-19 vaccination and asthma exacerbation. This research was granted by University of Parma through the action Bando di Ateneo 2021 per la ricerca co-funded by MUR-Italian Ministry of Universities and Research - D.M. 737/2021 - PNR - PNRR ? NextGenerationEU.