FIGURE 4.

Screening of biparatopic/bivalent Nanobody library in the P3X63 cell death assay. Shown are the inhibition percentages of P. aeruginosa-mediated cell death of the 65 most potent clones (of 960 clones screened) in a 1:150 dilution of crude periplasmic extract. Inhibition percentages of P. aeruginosa-mediated cell death are expressed relative to the assay window spanned by the condition in the absence of P. aeruginosa (no P. aeruginosa-mediated cell death) and the condition in the presence of P. aeruginosa without blocking Nanobody (no inhibition of P. aeruginosa-mediated cell death). Values boxed in white, light gray, and dark gray are means of one, two, or three clones, respectively. The building blocks of the biparatopic/bivalent Nanobodies are grouped per epitope bin (according to Fig. 2). freq hits, proportion of a given building block or epitope bin across all 65 hits. freq lib QC, the proportion of a given building block or epitope bin across a random quality control sample of 65 library clones. Statistics are detailed in supplemental Table S2.