Construction and characterization of YF/NIEV chimera. Construction and characterization of YF/NIEV chimera. (A) Schematic drawing of the YF/NIEV chimera. The envelope proteins prM and E of YFV were exchanged against the corresponding prM and E proteins of NIEV (green boxes). (B) Plaque morphology of YFV and YF/NIEV. C6/36 cells were electroporated with in vitro RNA transcripts of the indicated constructs or were mock transfected and processed for infectious center assay analyses. Seeded cells were overlaid with tragacanth. At 7 days p.e., cells were fixed and subjected to crystal violet staining. (C) Growth kinetics of YFV and YF/NIEV. C6/36 cells were infected at an MOI of 0.1. Quantification of viral genome copies in the supernatant was performed by real-time PCR. Data represent means and ranges of results of duplicate infection experiments. (D) Immunofluorescence analyses after infection of different cells. C6/36 or BHK cells were infected with the indicated viruses at an MOI of 0.1. At 48 h p.i., immunofluorescence analysis was performed using a monoclonal anti-YFV NS1 antibody. Nuclei were DAPI stained. Sandra Junglen et al. mSphere 2017; doi:10.1128/mSphere.00375-16