42001:

Immunoglobulins from plants: breaking the barriers to antibody production.

Authors:	Hein, Mich, B.(A)
Affiliations:	(A): EPIcyte Pharmaceutical, Inc.
Presenter:	Hein, Mich B., mbhein@epicyte.com

Only recently has the ability to produce transgenic proteins in plants been exploited commercially. In choosing production methods for proteins like antibodies it is often overlooked that plants are higher eukaryotic organismswith the capacity to produce and secrete complex multimeric proteins. Plants are the most efficient producers of protein on the planet. Plants have well developed endomembrane systems capable of recognizing protein processing, post-translational modification and assembly signals in peptide sequences. These cognate mechanisms for protein processing provide important advantages for plants as bioreactors. Plant production systems provide breakthroughs in the cost, the scale of production and the scope of molecules that can be efficiently manufactured. Antibodies for use in humans and animals from exogenous sources are a supplement to the immune system that can provide effective treatment for many diseases. The use of antibodies in the last 20 years has focused on monoclonal antibodies. Monoclonals have been investigated for treating a variety of disease states. The most successful applications for monoclonals have been in organ transplantation/ rejection therapy and management of other post-surgical or post-trauma conditions. A large number of antibody candidates have shown promise for cancer therapy. These two disease categories have in common their high morbidity and mortality while requiring relatively small capacity for antibody production. Other antibodies that have received attention are those effective in treating inflammatory and autoimmune disease and those which can impact systemic infection. Prior to Plantibodies there has been no cost effective or large-scale means of producing antibodies for such large scale applications and markets. With antibody production in plant systems it is now possible to produce tens of thousands of kilograms of any antibody. In addition, the absence of animal viruses and prions and the economy of scale possible for Plantibodies may provide cost advantages in purification, QA and QC. Markets that have been inaccessible for antibodies because of high costs may now be accessible, opening up possible uses in industrial separations and purification, and in all segments of the human and animal health markets. Employing professional crops such as corn, rice wheat or soybeans for antibody production should eliminate the major barriers to large scale antibody manufacturing within the next five years.