Proportions of individuals with auto-Abs neutralizing type I IFNs in seven new cohorts. (A and B) Frequency of individuals carrying auto-Abs neutralizing type I IFNs at concentrations of 10 ng/ml (A) or 100 pg/ml (B), as determined in luciferase-based neutralization assays, in the three defined groups of WNV-infected individuals: WNVIC, WNVF, and WNVD. IFN-α, auto-Abs neutralizing IFN-α2 (regardless of their effects on other IFNs); IFN-ω, auto-Abs neutralizing IFN-ω (regardless of their effects on other IFNs); IFN-α ± ω ± β, auto-Abs neutralizing IFN-α2 and/or IFN-ω and/or IFN-β; IFN-α + ω, auto-Abs neutralizing both IFN-α2 and IFN-ω. (C) Number of type I IFNs neutralized in the three groups of WNV-infected individuals (WNVIC, WNVF, and WNVD), as determined with the luciferase-based neutralization assay. (D) Proportion of type I IFNs neutralized in the three groups of WNV-infected individuals (WNVIC, WNVF, and WNVD) according to the nature and combination of auto-Abs.