Expression of S protein in insect larvae
R. nu larvae were from AgIdea (Pergamino, Argentina). They were
reared in trays at 23–25 °C in a 70% humidified chamber, with a 16:8
light:dark photoperiod, and fed a high wheat-germ diet until they
reached their fifth instar (20 days of age) prepared by AgIdea
(Pergamino, Argentina). For all the experiments, batches of 500
fifth-instar larvae were injected with 50 µL of the recombinant
baculovirus stock (diluted to 1×107 PFU mL−1) near the
third prolegs, as shown in Figure 2. To characterize and quantify the
recombinant protein produced, larvae that were alive and fluorescent
under UV light were harvested at day 4 post-infection and frozen
immediately at −80 °C until they were processed for analysis. Larvae
infected with a non-related recombinant baculovirus were included as the
control.