Ten larvae from each group were injected with VHSV (~103 TCID50/larvae), and control fish were injected with phosphate-buffered saline (PBS). Fish were incubated at 18°C. At different time points, the fish were frozen and homogenized in 1 mL PBS, and cholesterol levels were measured using a Stanbio Cholesterol LiquiColor® kit (Stanbio Laboratory, TX, USA). Cholesterol content was standardized according to the amount of genomic DNA in the samples.
Viperin-stabilized cells were used for in vitro lipid analysis. The cells were infected with rVHSV (16 (link)) and fixed in 4% paraformaldehyde (Electron Microscopy Sciences) at room temperature (RT) for 10 min. The cells were washed with 1× PBS. The working oil redo solution (Sigma, USA) was prepared by mixing the oil redo stock (0.5% in 2-propanol) in dH2O at a 3:2 ratio. The working solution was added to the cells, which were subsequently incubated for 15 min at RT. The cells were washed with dH2O and imaged at ×40 magnification (Leica Microsystems, Germany).
Viperin-stabilized cells were used for in vitro lipid analysis. The cells were infected with rVHSV (16 (link)) and fixed in 4% paraformaldehyde (Electron Microscopy Sciences) at room temperature (RT) for 10 min. The cells were washed with 1× PBS. The working oil redo solution (Sigma, USA) was prepared by mixing the oil redo stock (0.5% in 2-propanol) in dH2O at a 3:2 ratio. The working solution was added to the cells, which were subsequently incubated for 15 min at RT. The cells were washed with dH2O and imaged at ×40 magnification (Leica Microsystems, Germany).