Many antibodies and antibody derivatives have been produced in plant systems (Table 16.1) but only seven have reached advanced stages of product development and in main pipeline to achieve commercial status.
1. Avicidin:
This is an immunoglobulin G (IgG) produced in corn plants, was the first, to be administered to humans and showed some anti-cancer activity. However, product was withdrawn by NeoRX and Monsanto Company because of severe side effects.
2. CaroRX:
This is a chimeric secretory IgA/G that is produced in transgenic tobacco plants through the expression of four separate transgenes. These were stacked by gene pyrimiding process after crossing of independent transgenic plants that each plant expressed a different antibody component. This is used for streptococcus mutans to control tooth decay in humans.
3. T84.66:
T84.66 is a monoclonal antibody that recognized carcinoembryonic antigen (CEA). It has also been widely tested for cancer imaging and therapy. Derivatives like single chain FV fragment (SCFU) 84.66 have been produced in many different plant systems.
4. 38C13:
This ScFV antibody is based on the idiotype of malignant B lymphocytes in mouse lymphoma cell line 38C13. It is used in effective therapy for non-Hodgkin lymphoma. The antibodies were produced using virus infected plants rather than transgenic plants.
5. PIPP:
It is a monoclonal antibody that recognise human chorionic gonadotropin (hcG). The full- length MAB, as well as ScFV has been produced in transgenic plants and by agroinfiltration in transformed tobacco. The antibody could be used for diagnosis and therapy for tumours that produced hcG, pregnancy detection and contraception.