Treatment with Omalizumab in adults with severe allergic reduces Fc?I expression on dendritic cells and improves antiviral responses

Abstract

Introduction and Aim: Severe asthma is characterised by frequent exacerbations with the majority triggered by viral infections. Treatment of severe allergic asthma with Omalizumab reduces exacerbation risk. We sought to determine how Omalizumab improved antiviral innate immune responses to influenza A (IAV) and rhinovirus (RV). Methods: We recruited 10 adults, with severe allergic asthma and 10 healthy controls. Participants were assessed at basdeline 4 and 24 weeks after treatment. Peripheral blood monocytes (PBMCs) were isolated, exposed to IAV, RV. Monocyte cell types and FceI expression was identified by flow cytometry, Response was assessed by ELISA/RNA for FceI, interferon (IFN)-a, IFN-l, IFN-g, IL-6, IL-10. Results: At base line visit subjects with severe allergic asthma compared to healthy controls demonstrated impaired IFN-α, and IFN-λ release in response to IAV (p Conclusion: Adults with severe allergic asthma demonstrate impaired systemic DC immune responses to IAV and RV. Treatment with Omalizumab, that results in reduced exacerbations is associated with reduced DC FceI expression, enhanced DC IFN-α/λ responses to viruses and this effect is seen within 4 weeks treatment.