Figure 5.

Benzoselenoxanthene analogues inhibit influenza virus propagation. (A) Compounds inhibit IAV (A/PR8/34) in vitro. Firstly, Calu-3 cells were treated with compounds or Oseltamivir and Camostat as references for 24 h, then, infected with IAV and followed by culture in compounds contained medium, finally, supernatants were collected at 48 h after infection and viral titers were determined by plaque assay. (B) Compounds suppressed cytopathic effect. After Calu-3 cells were treated with compounds (8 μM) and infected with IAV (A/PR8/34, herein, abbr.: PR8) as described above, photos were collected at 48 h after infection. (C) The inhibitory effects of Se1, Se3 and Se5 on IAV spread can be rescued by trypsin. Firstly, Calu-3 cells were treated with compounds or Oseltamivir as references for 24 h, then, infected with IAV and followed by culture in compounds and trypsin (4 μg/mL) contained medium, finally, supernatants were collected at 48 h after infection and viral titers were determined by plaque assay. All of experiments were repeated three times. Statistical significance was determined using Student’s two-tailed t-test (A,C). *P < 0.05, **P < 0.01, ***P < 0.001. Error bars represent the SEM of three independent experiments.