Figure 4.

SARS-CoV-2 SPs influenced Sertoli cells’ autophagy. (A) TEM images of autophagic vacuoles in Sertoli cells; (A-a–A-e) cells were studied by electron microscopy at 48 h post-transfection with plasmids. The black triangles were autophagosomes for early autophagic vacuoles (AVi). The black stars were degradative autophagic vacuoles (AVd). (A-f) Quantification of the AVis and AVds per cell image. The average number of vesicles in each cell was obtained from at least five cells. (B) Immunoblotting analysis of the expressions of autophagy-related proteins. (B-a) The protein level of LC3 and P62 in Sertoli cells transiently transfected with SARS-CoV-2 structural proteins, with GAPDH serving as an internal control. (B-b–B-d) The relative levels of the targeted proteins were shown by histograms representing density readings of the gel bands, and the ratios were calculated relative to the GAPDH control. The data represent the mean ± SD of three independent experiments. * p < 0.05, ** p < 0.01, calculated using the Student’s t-test of SARS-CoV-2 SPs transfected cells vs. empty plasmid transfected cells.