Antibody-based
therapies (immunotherapies) are being applied to the treatment of
a wide range of diseases, including immune disorders, cancer and inflammatory
diseases. Such therapies will require an inexpensive and safe source
of antibodies. Transgenic plants offer an attractive method for large-scale
production of antibodies for immunotherapy.
The
expression of human antibody genes in plants results in the production
of antibodies that are free from contamination (e.g. viruses or prions).
However, a serious obstacle to the use of transgenic plants to produce
immunotherapy reagents is the fundamental difference in the process
of glycosylation between mammalian and plant cells.
Glycosylation
(the addition of sugar groups to a protein molecule) can affect the
activity of many antibody molecules. This hurdle has now been overcome
by ingenious experiments performed by Loïc Faye and colleagues
in the "Signaux et régulations chez les végétaux,"
(Plant Signaling and Regulation) Laboratory, CNRS-Université
de Rouen together with collaborators in Wageningen, the Netherlands.
They produced transgenic tobacco plants that have modified sugar metabolism.
They then crossed these plants with transgenic plants expressing antibody
proteins. This cross resulted in tobacco plants that produced recombinant
antibody molecules with a glycosylation pattern that was partially
humanized. These results represent a major advance towards the use
of transgenic plants for the production of human proteins compatible
with therapeutic applications in humans.
