Fig. 2.
Characterization of VSV G-CR2 and VSV G-CR3 interaction a Isothermal titration calorimetry (ITC) analysis between Gth and CR1, Gth and CR2, Gth and CR3 at 20 °C. Representative plots of each ITC experiments are illustrated with raw data in the upper panel. Binding parameters were determined by curve fitting analysis with the single-site binding model. The values indicated in the panel are those corresponding to the curves that are presented. Kd values given in the text are means of three independent experiments±standard errors. b, c Inhibition of VSV infection by soluble forms of CR domains. b BSR cells were infected with VSV-eGFP preincubated with GST-CR1, GST-CR2, GST-CR3 (upper part), CR1, CR2, or CR3 monovalent domains (lower part) at the indicated concentrations. Cells were fixed 4 h p.i. Only infected cells are expressing eGFP. Note that neither CR1 nor GST-CR1 construction protect cells from infection. DAPI was used to stain the nuclei. Scale bars=100 µm. c VSV-eGFP was preincubated with increasing concentrations of GST-CR2, GST-CR3, CR2, or CR3 monovalent domains. At 4 h p.i., the percentage of infected cells was determined by counting the number of cells expressing eGFP using a flow cytometer. The percentage of neutralization was equal to 100 × [1−(% of infected cells in presence of CR)/(% of infected cells in the absence of CR domains)]. Data depict the mean with standard error for experiments performed in triplicate