Bac to Bac System Efficiency for Preparing HPV Type 16 Virus-Like Particle Vaccine

• Published in: Archives of Razi Institute Vol. 78; no. 3; pp. 997 - 1003
• Main Authors: Razavi-Nikoo, H, Behboudi, E, Aghcheli, B, Hashemi, S M A, Moradi, A
• Format: Journal Article
• Language: English
• Published: Iran 01.06.2023
• Subjects: Animals; Baculoviridae; Human papillomavirus 16 - genetics; Humans; Microscopy, Electron; Papillomavirus Infections; Recombinant Proteins - genetics; Vaccines, Virus-Like Particle - genetics; Vaccine; Baculovirus; L1; Protein purification; Sf9; HPV
• ISSN: 2008-9872
• DOI: 10.22092/ARI.2023.361975.2708

Today, the human papillomavirus (HPV) L1 protein is the main target in the construction of prophylactic HPV vaccines. The production of virus-like particles (VLPs) that closely resemble the natural structure of the HPV16 virus and induce high levels of virus-neutralizing antibodies in animals and humans is facilitated by the expression of HPV16-L1 protein in eukaryotic cells. The Bac-to-Bac system has been previously used to produce high levels of recombinant proteins. In this study, we utilized this expression system to generate HPV16-L1 VLPs in (Sf9) insect cells. The wild-type L1 gene of papillomavirus type 16 was selected from Gene Bank and placed in bacmid structure after codon optimization using pFast Bac vector. The recombinant baculovirus containing HPV-16/L1 gene was then provided using the Bac-to-Bac system. It should be mentioned that the vector was transfected into the Sf9 cell. The cells were then lysed and the expression of L1 protein was revealed by SDS-PAGE and confirmed by Western Blot. The L1 purification was performed through Ni-NTA chromatography. The VLP formation of papillomavirus L1 protein was visualized by transmission electron microscopy. The expressed recombinant L1 was ~60 KD on SDS-PAGE which was identified in western blot by a specific anti-L1 monoclonal antibody. The electron microscopy confirmed the assembly of VLPs. Results of this study showed that the production of this protein at the industrial level can be optimized using a baculovirus/Sf9 system. The characteristics and advantages of this system are promising and it is a suitable candidate for protein synthesis.