FIG 3.

(A to G) Overlay of sensorgrams showing the dose-dependent binding of MAbs C2, C3, C4, C6, and C7 (A to E, respectively) and MAb AP33 (F) to sE2 recombinant protein immobilized on Biacore sensor chips. No interaction was detected using an IgG1 isotype at a concentration of 5 μM (G). All experiments were carried out at 25°C and a constant flow rate of 20 μl/min using HBS as the running buffer. The values of the binding parameters are reported in Table 2. (H) SDS-PAGE analysis (12% bisacrylamide) of purified sE2 used for SPR binding studies. Lane M, Precision Plus protein standards (10 to 250 kDa; Bio-Rad); lane 1, 2 μg of purified sE2 under reducing conditions. Proteins were visualized by the use of Bio-Safe Coomassie blue stain.