The patent (No 6,761,914), broadly covers composition of matter and methods for preparation and administration of immunogenic formulations involving antigen coated plant seed oilbodies, vessels within plant seeds used to store oils and oil-soluble compounds.
SemBioSys has developed a commercial protein production system based on this oilbody research. The Stratosome Biologics System is claimed to be cost effective, easily scaleable and caters for not only vaccines but also other protein and peptide drugs.
The Canadian firm I already exploring the use of the system to make insulin and apolipoprotein A1, a potential cardiovascular disease treatment. The company also entered into an agreement with Syngenta last year, giving the ag-biotech company an option to use the technology for the production of their proprietary biologics.
Using Stratosome, genetic engineering is used to introduce a transgene encoding an fusion protein of the target gene and oleosin into the plant. As the plant grows and the seed develops, the oleosin/target gene fusion is expressed to produce a recombinant protein, such as insulin or Apo AI, in the oilbody.
Seed is produced from the genetically engineered plants using conventional farming practices that have been adapted to ensure product integrity and confinement. The harvested seed is then processed using a proprietary oilbody extraction process. In cases where the oilbody/recombinant protein fusion is the desired finished product, this is the endpoint of the process and the product can then be formulated and packaged for its intended application.
In cases where a purified protein such as insulin or Apo AI is the end product, an enzyme or chemical that recognizes a cleavage site between the target protein and the oleosin is added to purified oilbodies cleaving the recombinant protein from the oleosin.
The oilbodies are then removed via centrifugation and the recombinant protein can then be purified simply and economically using conventional downstream processing.
SemBioSys' CEO, Andrew Baum, said that the new patent "broadens our proprietary Stratosome oilbody based protein production technology, protecting the breadth of its available applications and opening new market opportunities."
He said the company had already signed an agreement with Dow AgroSciences to evaluate the utility of the Stratosome technology for the development of an animal vaccine.
The worldwide market for preventive vaccines will total nearly $7 billion in 2004 despite the widely reported supply interruptions of flu vaccine in the US, according to a new study released by Kalorama Information. Both adult and paediatric vaccines will see strong growth upwards of 10 to 15 per cent annually over the next five years.