France's BioProtein Technologies, a biotechnology company specialising in the production of therapeutic proteins in the milk of transgenic rabbits, has extended its biomanufacturing services to include recombinant vaccine production.
BioProtein has developed a method of expressing antigen-carrying vectors, called rotavirus-virus-like particles (rotavirus-VLPs) in the rabbits' milk. The approach allows the insertion of a wide range of antigenic molecules into the particles, from small peptides to large polypeptides carrying multiple immune-stimulating sites.
Rotavirus-VLPs are high molecular weight protein complexes consisting ofhundreds of rotavirus proteins of two types: VP2 and VP6. These proteins arederived from the rotavirus capsid, and assemble naturally to form virus-likeparticles, mimicking the rotavirus structure, with the same ability totrigger the immune system but without the risk of infection.
"Rotavirus-VLPs represent a very powerful vaccine carrier due to their high molecular weight and the repetition of the antigen motif in each particle," said BioProtein. Recombinant chimeric proteins can be produced with any antigen of interest inserted within the VP2 and VP6 protein without disrupting the Rotavirus-VLP structure.
The technology is based on research developed in partnership with INRA, the French Agronomy Research Institute, and is the subject of a patent application (PCT/FR01/00676). BioProtein notes that it can be applied to a wide range of diseases, such as life-threatening viral infections (including HIV) and cancers.
Rabbits offer advantages over other transgenics in terms of scale-up and time-to-market and can produce up to 10-15 litres of milk per year, according to the company. From the annual production of 400 rabbits, up to 5-10kg of protein can be isolated and purified to a very high quality, it added.
Marc Le Bozec, CEO of BioProtein, said that the achievement broadens the company's commercial offering in the area of recombinant biopharmaceutical production in the milk of transgenic rabbits.