Detection of Nb6-pFc interacted with Nsp9. A ELISA detection of binding with prokaryotic expressedNsp9. Different concentrations of Nb6-pFc interacted with Nsp9. His-Nb6 and Nb53-pFc were used as positive and negative antibody controls, respectively. Assays were performed in duplicate, and data are presented as mean ± SD. B IFA detection of binding with PRRSV Nsp9. Nb6-pFc and Nb53-pFc were detected by Alexa flour 488-conjugated goat anti-swine IgG (Green) and positive infected cells were stained by mouse anti-Nsp9 serum (Red). C MARC-145 cells were inoculated with SD16 at a MOI of 0.1 for 36 h, and Nsp9 was pulled down by Nb6-pFc and Nb53-pFc. The bound proteins were detected by Western blot using mouse anti-Nsp9 serum and HRP-conjugated goat anti-swine IgG Fc.