Anti‐IFN‐α/‐ω neutralizing antibodies from COVID‐19 patients correlate with downregulation of IFN response and laboratory biomarkers of disease severity
Federica Frasca, Mirko Scordio, Letizia Santinelli, Lucia Gabriele, Orietta Gandini, Anna Criniti, Alessandra Pierangeli, Antonio Angeloni, Claudio Maria Mastroianni, Gabriella d’Ettorre, Raphael P. Viscidi, Guido Antonelli, Carolina Scagnolari
Abstract
A significant number of COVID-19 patients were shown to have neutralizing antibodies (NAB) against IFN; however, NAB specificity, fluctuation over time, associations with biochemical and hematological parameters, and IFN gene expression are not well characterized. Binding antibodies (BAB) to IFN-α/-β were screened in COVID-19 patients' serum. All BAB positive sera, and a subset of respiratory samples, were tested for NAB against IFN-α/-β/-ω, using an antiviral bioassay. Transcript levels of IFN-α/-β/-ω and IFN-stimulated genes (ISGs) were quantified. Anti-IFN-I BAB were found in 61 out of 360 (17%) of patients. Among BAB positive sera, 21.3% had a high NAB titer against IFN-α. A total of 69.2% of anti-IFN-α NAB sera displayed cross-reactivity to IFN-ω. Anti-IFN-I NAB persisted in all patients. NAB to IFN-α were also detected in 3 out of 17 (17.6%) of respiratory samples. Anti-IFN-I NAB were higher in males (p = 0.0017), patients admitted to the ICU (p < 0.0001), and patients with a fatal outcome (p < 0.0001). NAB were associated with higher levels of CRP, LDH, d-Dimer, and higher counts of hematological parameters. ISG-mRNAs were reduced in patients with persistently NAB titer. NAB are detected in a significant proportion of severe COVID-19. NAB positive patients presented a defective IFN response and increased levels of laboratory biomarkers of disease severity.