Fig 4.

Infection of PESU-B5L cells with human coronavirus NL63 expressing GFP. PESU-B5L cells were infected with mock or NL63gfp at an MOI of 0.25 and monitored by bright-field and fluorescence microscopy. (A and B) Mock-infected cells by bright-field (A) and fluorescence (B) microscopy. (C through F) Cells infected with NL63gfp visualized at day 3 postinfection by bright-field microscopy (C) and by fluorescence microscopy (D) and at day 5 postinfection by bright-field microscopy (E) and by fluorescence microscopy (F).