Proceedings of the XLVII Italian Society of Agricultural Genetics - SIGA Annual Congress

Verona, Italy - 24/27 September, 2003

ISBN 88-900622-4-X

Oral Communication Abstract - S3a

EXPLOITING THE PLANT PROTEIN SECRETORY PATHWAY FOR PRODUCTION OF RECOMBINANT MOLECULES FOR PASSIVE AND ACTIVE IMMUNISATION

J. MA, D. CHARGELEGUE, P. DRAKE, P. OBREGON

St. George's Hospital Medical School, London SW17 0RE

julian.ma@kcl.ac.uk

One of the key advantages that plants offer for the expression of recombinant proteins is that they are higher eukaryotic organisms with an endomembrane system. Therefore they fold and assemble recombinant proteins using protein chaperones that are homologous to those in mammalian cells, and they perform post-translational modifications.

Plants expressing IgG monoclonal antibody was first described in 1989. Since then, transgenic plants have proven to be extremely versatile, successfully used for antibody fragments, IgG and secretory IgA antibodies, the latter already having been taken through clinical trials. A considerable amount of work has also been performed on the expression of antigens in plants, particularly with a view to oral delivery. To date, three examples have been tested in humans - E. coli heat labile toxin, hepatitis B surface antigen and Norwalk virus capsid protein.

Overall, proof of principle has been demonstrated for the production of recombinant pharmaceutical in plants. Plants would appear to represent one of the few systems capable of delivering complex glycoproteins in the quantities required for vaccines, particularly in developing countries.