Fig 4

Co-endocytosis of HSPA5 with CV-A9. a The peptide blocking assay. The infectivity of CV-A9 was blocked by the ESPLSLVA peptide and RRRGEL was used as negative control. Cells were fixed six hours post-infection, permeabilized and the virus was stained with specific antibodies. Nuclei were stained with Hoechst and the infectivity was measured with Victor³ multilabel counter. Error bars indicate the standard deviation from four independent samples and significance P = 4.0 × 10⁻⁵ is indicated with asterisk (***) or stated as not significance (NS). b Confocal imaging of abundance of HSPA5 on the surface of SW480 cells (non-permeabilized cell) and in the cell interior (permeabilized cell). Non-infected cells were stained with the HSPA5 specific antibody shown in red. c Co-internalization of CV-A9 and HSPA5. The cells were stained with virus-specific (green) and HSPA5-specific (red) antibodies in non-permeabilized (0 min) cells to show the cell surface binding or in permeabilized cells (5 min) to show the CV-A9/HSPA5 internalization. The nuclei were stained with Hoechst (blue). Co-localization of CV-A9 and HSPA5 is visualized by yellow color in the merged images. Scale bars are 10 μm