Production of H5N1 Influenza Virus Matrix Protein 2 Ectodomain Protein Bodies in Tobacco Plants and in Insect Cells as a Candidate Universal Influenza Vaccine

Sandiswa Mbewana; Elizabeth Mortimer; Francisco F P G Pêra; Inga Isabel Hitzeroth; Edward P Rybicki

doi:10.3389/fbioe.2015.00197

Production of H5N1 Influenza Virus Matrix Protein 2 Ectodomain Protein Bodies in Tobacco Plants and in Insect Cells as a Candidate Universal Influenza Vaccine

Front Bioeng Biotechnol. 2015 Dec 8:3:197. doi: 10.3389/fbioe.2015.00197. eCollection 2015.

Authors

Sandiswa Mbewana¹, Elizabeth Mortimer¹, Francisco F P G Pêra¹, Inga Isabel Hitzeroth¹, Edward P Rybicki²

Affiliations

¹ Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town , Rondebosch , South Africa.
² Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town , Rondebosch , South Africa ; Institute of Infectious Disease and Molecular Medicine, Faculty of Heath Science, University of Cape Town , Cape Town , South Africa.

Abstract

The spread of influenza A viruses is partially controlled and prevented by vaccination. The matrix protein 2 ectodomain (M2e) is the most conserved sequence in influenza A viruses, and is therefore a good potential target for a vaccine to protect against multiple virus subtypes. We explored the feasibility of an M2e-based universal influenza A vaccine candidate based on the highly pathogenic avian influenza A virus, H5N1. A synthetic M2e gene was human- and plant-codon optimized and fused in-frame with a sequence encoding the N-terminal proline-rich domain (Zera(®)) of the γ-zein protein of maize. Zera(®)M2e was expressed transiently in Nicotiana benthamiana and Sf21 baculovirus/insect cell expression systems, and Zera(®)M2e protein bodies (PBs) were successfully produced in both expression systems. The plant-produced Zera(®)M2e PBs were purified and injected into Balb/c mice. Western blot analysis using insect cell-produced Zera(®)M2e PBs and multiple tandem M2e sequences (5xM2e) fused with the avian influenza H5N1 transmembrane and cytosolic tail (5xM2e_tHA) confirmed the presence of M2e-specific antibodies in immunized mice sera. The immunogenicity of the Zera(®)M2e indicates that our plant-produced protein has potential as an inexpensive universal influenza A vaccine.

Keywords: M2e; influenza A virus; insect cell expression; plant expression; vaccine.