Differential Sensitivity of Bat Cells to Infection by Enveloped RNA Viruses: Coronaviruses, Paramyxoviruses, Filoviruses, and Influenza Viruses (original) (raw)
Figure 6
Effect of trypsin-treatment on the ability of SARS-CoV S and SARSr-CoV Bg08 S to induce syncytia formation when co-expressed with human or RhiLu/1.1_ACE2.
BHK-21 cells, grown on coverslips were co-transfected with different combinations of expression plasmids for either (a) SARS-CoV S (SARS-CoV S-DsRed), or (b) SARSr-CoV Bg08 S (SARSr-CoV Bg08 S-DsRed), and ACE2 molecules of human (hACE2) or chiropteran (Rhinolophus alcyone, RhiLu/1.1_ACE2) origin. In both cases, empty pCG1 vector served as controls (pCG1). At 24 h post transfection, cells were either treated with medium containing trypsin (+ trypsin) to enable proteolytic activation of the CoV S or were left untreated (- trypsin). Subsequently, ACE2 was stained by antibody incubation (α-ACE2) and screened for syncytia formation by fluorescence microscopy. All tests were performed in triplicates and repeated three times.