Auto-antibodies neutralizing type I interferons in ~10% of Moroccan patients with life-threatening COVID-19

Autoantibodies neutralizing type I interferon (AAN-I-IFN) have been found in at least 10-15% of critical COVID-19 pneumonia cases in various studies across North and Latin America, Oceania, Europe, and Asia. We sought to analyze the prevalence of AAN-I-IFN and describe the demographic, clinical, and laboratory characteristics in a Moroccan cohort of patients with life-threatening COVID-19.

We performed a cross-sectional and multicenter study of patients hospitalized in different university hospitals and clinical centers in Casablanca between November 2020 and December 2021.

Our cohort included 195 patients with proven SARS-CoV-2 infection, 164 (84.1%) of whom developed severe or critical COVID-19 disease requiring hospitalization, and 31 (15.9%) patients developed mild or moderate disease. Patients with moderate or mild COVID-19 did not exhibit detectable levels of AAN-I-IFNs. Among the 20 patients with AAN-I-IFN, most were men (n=16, 80%), and age ranged from 19 to 101 years. 13 (65%) patients with severe COVID-19 and 7 (35%) with critical COVID-19 had AAN-I-IFNs. Twelve patients (60%) had autoantibodies (auto-Abs) neutralizing both high and low concentrations of IFN-α2 and/or IFN-ω, five (25%) had auto-Abs neutralizing only low concentrations of IFN-α2 or IFN-ω, two (10%) had auto-Abs neutralizing IFN-β (1ng/mL) only, and one (5%) had auto-Abs neutralizing high and low concentrations of IFN-α2 and IFN-ω, as well as IFN-β at 1ng/mL, but none neutralized IFN-β at 10 ng/mL.

Overall, AAN-I-IFNs were detected in 20/195 (10.3%) of Moroccan patients with life-threatening COVID-19 and in 20/164 (12.2%) patients with severe or critical disease, whereas none were detected in patients with mild or moderate COVID-19.