Fig. 1

PRV infectivity in porcine ovarian granulosa cells. Granulosa cells were infected with PRV suspension (a titer of 50 TCID₅₀) at 37 °C for 1.5 h to allow viral attachment, then collected for viral nucleic acid analysis or for transmission electron microscopy analysis. (A) Nucleic acid level of PRV gE in porcine granulosa cells infected with PRV at different time points. Statistical analysis was compared with the 0 h group; data represented as mean ± SEM (n = 3); * P < 0.05, **P < 0.01. (B) Transmission electron microscopy (TEM) analysis. Porcine ovarian granulosa cells inoculated with PRV (50 TCID₅₀) was observed at 24 h post infection. A large amount of mature viral particles (dark color, about 200 nm in size) were observed, adhering to nuclear membrane of the PRV-infected cell, and immature viral particles presented in the cytoplasm; scale bars were 500 nm (left panel) and 100 nm (right panel), respectively. Yellow arrows indicate mature viral particle in dark color, about 200 nm in size, and red arrows indicate immature viral particle in light color, about 100 nm in size. N: nucleus; M: mitochondria