PMC

A) Expression cassette used to express the recombinant proteins under the control of the polh promoter in a conventional TB(-) baculovirus. B) Expression cassette used to express the recombinant proteins in a TB(+) baculovirus containing all genetic regulatory elements, including the transactivation elements encoded by Ac-ie-01 sequence, the enhancer sequence hr1, and the combination of promoters p6.9 and p10.

Extracts from infected cells at the optimal production times with each baculovirus were processed for VLP purification. The protein patterns of the purified VLPs obtained with each baculovirus are shown in the inserts (Coomassie blue stained). Samples were observed by Electron microscopy using negative staining. The figure shows the VLPs at two magnifications. VLPs obtained with the two baculoviruses presented identical sizes and shapes but were more abundant when produced by the TB(+) virus. The micrographs are representative of the fields analyzed.

Extracts from infected cells at the optimal production times with each baculovirus were processed for VLP purification. The protein patterns of purified VLPs obtained with each baculovirus are shown in the inserts (Coomassie blue stained). Samples were observed by Electron microscopy using negative staining. The figure shows the VLPs at two magnifications. VLPs obtained with the two baculoviruses presented identical sizes and shapes but were more abundant when produced by the TB(+) virus. The micrographs are representative of the fields analyzed.

A) Coomassie blue staining of SDS-PAGE gels resolving protein extracts obtained from cells infected with TB(-) or TB(+) baculoviruses and collected from 0 to 120 hpi. The same samples were submitted to a Western blot using a monoclonal antibody against the PCV2-Cap antigen. B) Infected cells viability at different hpi with TB(-) and TB(+) baculoviruses expressing the PCV2-Cap protein, analyzed by Trypan blue staining. This panel represents the mean values of three different experiments. C) Calculation of PCV2-Cap protein productivity in Sf9 cells infected by TB(-) and TB(+) baculoviruses at the optimal production time in each case (24 hpi for TB(-) and 48 hpi for the TB(+) baculovirus).

A) Coomassie blue staining of SDS-PAGE gels resolving protein extracts obtained from infected cells with TB(-) or TB(+) baculoviruses and collected from 0 to 96 hpi. The same samples were submitted to a Western blot using a monoclonal antibody against the RHDV-VP60 antigen. B) Infected cells viability at different hpi with TB(-) and TB(+) baculoviruses expressing the RHDV-VP60 protein, analyzed by Trypan blue staining. This panel represents the mean values of three different experiments. C) Calculation of VP60 protein productivity in Sf9 cells infected by TB(-) and TB(+) baculoviruses at the optimal production time in each case (72 hpi for TB(-) and 96 hpi for the TB(+) baculovirus).