Figure 3. Colocalization of pseudovirus with hACE-2 receptor or SARS-CoV-2 Spike protein in Vero E6 cell line. Cells were incubated with anti-SARS-CoV-2 Spike, human anti-ACE2 and DAPI. (A–D)Mock-treated VeroE6 cells with hACE2 staining. (E-H)VSV-ΔG-Sdel21 infected Vero E6 cells with hACE2 staining. (I-L)VSV-ΔG-Sdel21 infected Vero E6 cells with SARS-CoV-2 Spike staining. Yellow color shows viral S protein (J ), and red colors represents human ACE2 (B, F ). Scale bars, 20 μm. Data inA–L are representative images of two independent experiments.
To validate Spike and ACE2 protein expression of infected cells, immunostaining was performed using VSV-ΔG-Sdel21 pseudotyped virus. Meanwhile, colocalization of VSV-ΔG-Sdel21 and human ACE2 receptor was investigated. (Figure 3E-H) . Co-localization was not found in mock-treated hACE2 (Figure 3A–D), indicating that SARS-CoV-2 uses human ACE2 as a receptor for entry. In addition, colocalization of VSV-ΔG-Sdel21 and Spike protein confirmed the existence of Spike as a surface glycoprotein in our VSV-ΔG-Sdel21 pseudotyped particles