Translational fusion of chloroplast-expressed human papillomavirus type 16 L1 capsid protein enhances antigen accumulation in transplastomic tobacco

• Published in: Transgenic research Vol. 17; no. 6; pp. 1091 - 1102
• Main Authors: Lenzi, Paolo, Scotti, Nunzia, Alagna, Fiammetta, Tornesello, Maria L, Pompa, Andrea, Vitale, Alessandro, De Stradis, Angelo, Monti, Luigi, Grillo, Stefania, Buonaguro, Franco M, Maliga, Pal, Cardi, Teodoro
• Format: Journal Article
• Language: English
• Published: Dordrecht Dordrecht : Springer Netherlands 01.12.2008; Springer Netherlands; Springer; Springer Nature B.V
• Subjects: 5' Untranslated Regions; Animal Genetics and Genomics; Antibodies; Antigens; Biochemical Phenomena; Biological and medical sciences; Biomedical and Life Sciences; Biomedical Engineering/Biotechnology; Biotechnology; Capsid - immunology; Capsid - metabolism; Capsid protein; Capsid Proteins - biosynthesis; Capsid Proteins - genetics; Capsid Proteins - immunology; Capsid Proteins - ultrastructure; Capsids; Cervical cancer; Cervix; Chloroplasts; Chloroplasts - metabolism; Chloroplasts - ultrastructure; double prime L1 protein; Electron microscopy; Enzyme-Linked Immunosorbent Assay; Epitopes; Expression vectors; Feasibility Studies; Fundamental and applied biological sciences. Psychology; Gene Expression; Genetic Engineering; Genetic technics; Genetic transformation; Genetic Vectors; HPV16; Human papillomavirus; Human papillomavirus 16; Humans; Immunoblotting; Immunogenicity; L1 protein; Leaves; Life Sciences; Methods. Procedures. Technologies; Molecular Medicine; mRNA; Nicotiana - genetics; Nicotiana - immunology; Nicotiana - metabolism; Nicotiana - ultrastructure; Nicotiana tabacum; Oncogene Proteins, Viral - biosynthesis; Oncogene Proteins, Viral - genetics; Oncogene Proteins, Viral - immunology; Oncogene Proteins, Viral - ultrastructure; Original Paper; Plant Genetics and Genomics; Plant vaccines; Plants, Genetically Modified; Plasmids; Plastid transformation; Plastids; Proteins; Recombinant Proteins - biosynthesis; Recombinant Proteins - immunology; RNA, Messenger - metabolism; Tobacco; Transformation; Transgenes; Transgenic animals and transgenic plants; Transgenics; Translation; Vaccines; Plastid transformation; Plant vaccines; Tobacco; L1; HPV16; Vaccine; Papovaviridae; Plastid; Nicotiana tabacum; Accumulation; Protein; Papillomavirus; Virus; Antigen; Human papillomavirus 16; Human papillomavirus; Dicotyledones; Angiospermae; Spermatophyta; Solanaceae; Capsid; Chloroplast
• ISSN: 0962-8819; 1573-9368
• DOI: 10.1007/s11248-008-9186-3

Human Papillomavirus (HPV) is the causal agent of cervical cancer, one of the most common causes of death for women. The major capsid L1 protein self-assembles in Virus Like Particles (VLPs), which are highly immunogenic and suitable for vaccine production. In this study, a plastid transformation approach was assessed in order to produce a plant-based HPV-16 L1 vaccine. Transplastomic plants were obtained after transformation with vectors carrying a chimeric gene encoding the L1 protein either as the native viral (L1v gene) or a synthetic sequence optimized for expression in plant plastids (L1pt gene) under control of plastid expression signals. The L1 mRNA was detected in plastids and the L1 antigen accumulated up to 1.5% total leaf proteins only when vectors included the 5'-UTR and a short N-terminal coding segment (Downstream Box) of a plastid gene. The half-life of the engineered L1 protein, determined by pulse-chase experiments, is at least 8 h. Formation of immunogenic VLPs in chloroplasts was confirmed by capture ELISA assay using antibodies recognizing conformational epitopes and by electron microscopy.