Virus like particle production for H5N1 influenza using lentiviral technology

Traditional egg-based Influenza Live Virus, inactivated vaccines have major limitations and drawbacks, particularly for use in a Pandemic setting. High Pathogenicity Avian Influenza (HPAI) viruses, such as the H5N1 strains currently circulating in Asia, are too virulent to grow in eggs, and require a biohazard containment facility to handle. Lentigen has developed a fast, recombinant and highly immunogenic Virus-Like Particle (VLP) vaccine for H5N1 Influenza, based on the use of lentiviral technology to permanently transduce 293 cells to produce wholly Influenza VLPs. One of the advantages of the system is the continuous production of VLPs into the supernatant of medium, obviating batch production methods and reducing the scale and therefore expense for vaccine production. Influenza A H5N1 Vietnam 1203 Matrix 1, Hemagglutinin 5 (HA5), and Neuraminidase (NA1) genes were engineered into a lentiviral vector as a single genetic element, and the vector used to transduce HEK 293 cells. A cell line containing 25 copies per cell was selected and grown at high density, producing VLPs that budded into the supernatant. Concentrated supernatants were harvested and tested for the presence of the M1, HA, and NA proteins. M1 and HA were detected by Western Blot. HA was detected by ELISA and RBC agglutination, while NA was detected by ELISA and the Neuraminidase Umberifyll assay.