PNAS has published an article profiling the avian transgenic (Ova) system's ability to express two therapeutic proteins in the whites of eggs of transgenic hens
Oxford BioMedica and its collaborative partners in the field of avian transgenics, Viragen and Roslin Institute, report that the Proceedings of the National Academy of Sciences of the United States of America (PNAS), a leading scientific journal, has published an article profiling the avian transgenic (Ova) system's ability to express two therapeutic proteins in the whites of eggs of transgenic hens.
The Ova System is being developed as a novel, large-scale biomanufacturing alternative, capable of cost-effectively expressing many types of therapeutic proteins.
The article, entitled, 'Oviduct-specific expression of two therapeutic proteins in transgenic hens', reports on the production of two protein drug candidates: a humanised monoclonal antibody being developed by Viragen for advanced malignant melanoma and interferon beta-1a, which is currently marketed under two competing brand names for the treatment of multiple sclerosis (MS), as Avonex (Biogen Idec) and Rebif (Serono).
Article summary: Recent advances in avian transgenesis have led to the possibility of utilising the laying hen as a production platform for the large-scale synthesis of pharmaceutical proteins.
Ovalbumin constitutes more than half of the protein in the white of a laid egg, and expression of the ovalbumin gene is restricted to the tubular gland cells of the oviduct.
The authors describe the use of lentiviral vectors to deliver transgene constructs comprising regulatory sequences from the ovalbumin gene designed to direct synthesis of associated therapeutic proteins to the oviduct.
They report the generation of transgenic hens that synthesise functional recombinant pharmaceutical protein in a tightly regulated tissue-specific manner, without any evidence of transgene silencing after germ-line transmission.
According to Viragen vice president, Karen Jervis, who is managing director of Viragen's Scotland operations, additional avian transgenic milestones are expected shortly: "We are very pleased that the PNAS article chronicles our 'proof-of-principle' studies resulting in successful germline transmission of two therapeutic proteins, and we expect to report excellent new results with a third protein-drug candidate by the end of this month, assuming positive confirmations".
Professor Alan Kingsman, Oxford BioMedica's chief executive officer commented: "We are delighted by the progress of our collaborative partners towards the commercialisation of the OVA System.
"This technology could address a substantial need in the biopharmaceutical industry for efficient, high-volume production of biological products."
