Figure 6. JNK2, but not JNK1, protects mice against viral infection in vivo.

(A) Wild type C57BL/6, Jnk1 ^−/− or Jnk2 ^−/− mice (12 mice in each group) were infected with VSV at the indicated doses via nasal dripping (liquid volume≤20 µL). Survival rates of the mice were monitored at 5 days after infection. (B) The mice were intranasally challenged with VSV (10⁶ PFU/g mouse weight). Two days after infection, serum was collected from the mice. Equal volumes (10 µL) of serum were added to HEK293 cells culture media and incubated for 24 hours, followed by plaque assay using crystal violet staining. Viral plaques were observed by microscopy and the viral titer was calculated. (C) Data from B presented as means±SD (n = 3). (D) Wild type C57BL/6, Jnk1 ^−/− or Jnk2 ^−/− mice were infected with NDV-GFP (10⁶ PFU/g mouse weight). Two days after viral challenge, lungs were collected for fluorescence stereomicroscopy to observe NDV-GFP in situ. (E) Serum was collected at 2 days after NDV-GFP infection and equal volumes (100 µL) of serum were added to HEK293 cells culture media. Eighteen hours later, the NDV-GFP infected cells were observed by fluorescence microscopy. (F) GFP-positive cells from E were quantified by flow cytometry.