What are they???
• A plantibody is an antibody/proteins produced by genetically
• Uses: as edible vaccines, diagnostic/ therapeutic monoclonal
antibodies, for disease resistance in plants.
scFv or single
RISK BY BACTERIAL
SIZE, LOW COST
ABILITY TO EXPRESS
BY SEXUAL CROSSING
OF PROTEINS IN ER
The Plantibody Approach
- form Plant Molecular Biology (2000), 43, 419–428
COMPONENTS OF A PLANTIBODY GENE
• Plantibodies gene construct can contain sequence for fragment
(Fab, scFv, whole length antibody).
• Effective promoters for increased expression of proteins attached
upstream of the genes. Eg. Hsp70 promoter is more effective the
• Signal peptide sequence – needed for targeting of antibody into
ER for proper folding of protein.
• C-terminal peptide- usually KDEL added to C-terminal of the
peptide that can increase expression and retention of the protein in
Plant Cell Transformation
Transfer Of Antibody Genes
Direct Gene Transfer By
Gene Gun , Liposomes etc.
Insertion Of Transformed Cell Into Plant Embryo
Plant development and propagation in fields
PLANT BREEDING BY SEXUAL CROSS
with gene for
kappa chain of
with gene for
Plant with genes
New antibody combinations
can be produced.
Dual purpose vaccines can be
Properties like enhanced
expression, stability, binding
affinity can be achieved using
different promoters, signal
Mutations in CDRs of Vregions can enhance binding
affinity of antibodies.
PLANT TISSUE CULTURE
Differentiated plant cells states are grown in bioreactors and
foreign proteins harvested from either the biomass or culture
Cell cultures contain fewer biological proteins or molecules
which may contaminate the product.
Large amounts of proteins obtained in short time & less
Sexual reproduction is not needed to ensure the lifespan of the
species. Transgene stability is also increased.
Cannot be used for edible vaccines.
Treatment of infectious disease, inflammation, autoimmune
disease or cancer.
Tobacco produced mAb is more viable alternative to mAb
produced in mouse ascites fluid for the large amounts needed for
purification of hepatitis B vaccine.
World's first clinically tested plantibody, CaroRx binds
specifically to Streptococcus mutans, the bacteria that cause tooth
decay, and prevents the bacteria from adhering to teeth.
CaroRx is intended for regular topical preventative administration
by both dental hygienists and patients allowing a thorough cleaning
and intervention for any existing decay.
Potential proteins produced are
cytokines, hormones, enzymes, epidermal growth
factors, interferons,, and pharmaceutical foodstuff which are
considered for oral immunization.
Transgenic plants expressing antigens are
used as an inexpensive oral-vaccine production
and delivery system so immunization through
consumption of an "edible vaccine" to provide
passive immunity. Eg. Transgenic banana that
eaten,are like subunit preparations in that are
engineered to contain antigens subunit but bear
no genes that would enable whole pathogens
• One of these is a full-length IgG specific for EpCAM (a
marker of colorectal cancer) developed as the drug
Avicidin by NeoRx and Monsanto.It is under pre clinical
trial phase II.
• Other antibodies are CaroRx,scFvT84.66, AntiHSV, 38C13 and PIPP (antihCG).
• Oral cholera vaccine developed in potato .
Production Costs for Antibodies
cost in $ /gram
Source: Daniell et al. (2001) TIPS 6, 219-226
E. coli & yeast
Tr. animals and
Functional antibodies need:
• Need to be properly folded and assembled.
• Need disulfide bond formation and glycosylation.
• Glycosylation is different in plants.
• Only mannose is attached-shorter half-life of Ab.
Comparison of Mammalian and Plant-produced
Peptide sequence: identical
Correct cleavage of Ig-derived signal peptides
Kinetics & affinity: identical
Stability in seeds > 30 months
Antibody types: plant system more versatile (sIgA)
Post-translational processing: different
core glycan identical, terminal sugar different plus xylose & fucose
antigenicity & clearance: apparently identical (shorter half-life)
FULL-SIZE MONOCLONAL ANTIBODIES RECENTLY
PRODUCED IN TRANSGENIC PLANTS
Monoclonal antibody engineering in plants
•Andrew Hiatt , Julian K-C. Ma
•Department of Cell Biology, The Scripps Rcsearch Institute, La Jolla, CA 92037, USA
Plantibodies: applications, advantages and bottlenecks
Molecular Biotechnology Unit, John Innes Centre, Norwich Research Park, Norwich
NR4 7UH, UK
b Department for Molecular Biotechnology, RWTH Aachen, Worringerweg 1, 52074
PLANTIBODY: AN OVERVIEW(Asian journal of Pharmacy and Life Science, Vol. 1
(1), Jan-Mar, 2011)
Priya Jain*, Prasoon Pandey, Dheeraj Jain, Pankaj Dwivedi
College of pharmacy, IPS academy, rajendra nagar, Indore, India. 452012