Fig. 4

An increased level of cell surface vimentin induced by SARS-CoV VLPs. Vero E6 cells suspended in FACS buffer were incubated with SARS-CoV VLPs for 10 min at 4 °C. The cells were then fixed and analyzed with anti-vimentin antibodies and AlexaFluor 488-conjugated secondary antibodies. The fluorescence was quantified by using a LSR-II Digital Flow Cytometer and the data were analyzed by using FlowJo software. Vero E6 cells without the pre-treatment of SARS-CoV VLPs were used as a negative control (M1 region) and Vero E6 cells permeabilized with 0.1 % TritonX-100 for 5 min were used as a positive control (M2 region)