FIGURE 8.

Cpe30 in recombinant influenza HA retains binding activity to Cldn-4 Ecl2. C-terminally His-tagged HA-ts-Cpe30 and HA shown in A were expressed in baculovirus and purified to homogeneity. HA-specific antibody (H36) was immobilized to a CM5 chip by amine coupling, which was used to capture HA-ts-Cpe30 or HA protein as the ligand. Cldn-4 Ecl2.R4 was used as the analyte. B, overlay of sensorgrams of HA-ts-Cpe30 with different concentrations of Cldn-4.R4 show the specific interaction. C, HA protein without Cpe30 showed no binding to Cldn-4 Ecl2; the figure shows that the assay and control channels responded similarly at different concentrations of analyte.