Figure 1

Representative NPs from the Influenza Research Data Base and the anti-NP antibody discovery procedure. (A) The flow chart shows the schematic procedure determining representative NPs. The details of the procedure are delineated in the main text and the phylogenetic tree of the NP sequences from Influenza Research Database is shown in Supplementary Figure S1. The sequences of the representative NPs are shown in Supplementary Figure S2. (B) The anti-NP antibody discovery procedure with phage-displayed synthetic antibody libraries is depicted schematically in 5 steps: Step 1 shows the phage display antibody selection procedure with multiple phage-displayed scFv libraries (results shown in Supplementary Figure S3) against the 6 representative NPs determined by the procedure shown in (A); Step 2 shows the additional two rounds of phage display selection to enrich the scFv libraries binding to the antigen immobilized on the solid surface by adding excessive amount of NPs other than the immobilized target NP; Step 3 shows the screening criteria for positive monoclonal scFvs (results shown in Fig. 2); Step 4 indicates the reformation and expression of the positive scFvs to monoclonal IgG1s; Step 5 depicts the binding immunoassay of the monoclonal IgG1 to the immobilized antigen on the right-hand side (results shown in Figs. 3, 4) and the sandwich immunoassay on the left-hand side (results shown in Fig. 5).