Anti-NP mAbs bind with wild-type filovirus NPs. (A) ELISA plates were coated with 40 ng of purified irradiated filoviruses EBOV, SUDV, RESTV, TAFV, and MARV. Different concentrations of purified mAbs (3 μg–0.003 μg per well) were added in respective plates. After blocking, the bound antibodies were detected following incubation with horseradish peroxidase (HRP)-linked secondary goat anti-mouse IgG. The optical density (OD) was determined at 650 nm. (B) ELISA plates coated with 40 ng of EBOV, SUDV, MARV, BDBV, RESTV, and TAFV were treated with different concentrations of purified 2G10 and 4F9 mAbs (3 μg–0.003 μg per well) and analyzed via binding assay.