Dr. S. L. Deore
Mr. Sagar S. Alone
1. What it means ?
2. Difference Between Conventional & Edible Vaccines.
3. Methods for Transformation of DNA/Gene into
4. Production of Edible vaccine.
5. Mechanism of Action.
6. Advantages of Edible Vaccines.
7. Disadvantages of Edible Vaccine.
8. Clinical Trials.
What It Means ?
Introduction of selected desired genes into plants and then
inducing these altered plants to manufacture the encoded proteins
Gene is inserted into the DNA of plant (potato, banana, tomato).
Humans eat the plant.
The body produces antibodies against pathogen protein.
Human are “immunized” against the pathogen.
Edible Vaccines Stimulates Both 
1) Mucosal Immunity
2) Circulating Immunity
DifferenceBetween Conventional & EdibleVaccines 
Conventional Vaccine Edible vaccine
Poor mucosal response
Required cold chained
Required trained medical
Enhance compliance in
Eliminate trained medical
Good genetic stability
Not required cold chained
Stored near the side of use
Eliminate long distance
syringe & needles not required
No fear of contamination of
Methods forTransformationof DNA/Gene into Plants 
A. Vector mediated- Agrobacterium tumefaciens.
B. Vectorless or Direct gene transfer- It has variety of techniques,
1) Gene gun ( Biolistic method/Particle gun)
2) Electroporation(pulse of high voltage)
3) Microinjection[using fine tipped (0.5 - 1.0 micrometer
4) Chemical mediated gene transfer (polyethylene glycol (PEG) ,
dextran sulphate & Calcium phosphate)
6) Conjuction (natural microbial recombination )
Mechanism of action 
Antigens in transgenic plants are delivered
through bio-encapsulation (tough outer wall of
plant cells) protects them from gastric secretions.
Break up in the intestines.
Taken up by M cells in the intestinal lining.
Passed on to macrophages, other antigen-
presenting cells; and local lymphocyte
Generating serum IgG, IgE responses, local IgA
response and memory cells.
Which neutralize the attack by the real infectious
Advantages of Edible Vaccines 
Edible means of administration.
Reduced need for medical personnel and sterile injection conditions.
Storage near the site of use.
Possible production of vaccines with low costs.
Economical in mass production and transportation.
Easy for separation and purification of vaccines from plant materials.
Heat stable, eliminating the need for refrigeration.
Antigen protection through bioencapsulation.
Enhansed compliance (especially in children).
Effective prevention of pathogenic contamination from animal cells.
DISADVANTAGES OFEDIBLE VACCINE 
Development of immunotolerance to vaccine peptide or protein.
Consistency of dosage form fruit to fruit, plant-to-plant, and generation-to-
generation is not similar.
Stability of vaccine in fruit is not known.
Dosage of vaccines would be variable.
Selection of best plant is difficult.
Certain foods like potato are not eaten raw, and cooking the food might
weakens the medicine present in it.
Not convenient for infants.
Clinical trials 
Rabies- Tomato plants expressing rabies antigens could induce
antibodies in mice 
Cholera-Transgenic potato with CT-B gene of Vibrio cholerae was
shown to be efficacious in mice .
Norwalk virus- transgenic potato expressing norwalk virus antigen
showed seroconversion 
Hepatitis B- First human trials of a potato-based vaccine against
hepatitis B have reported encouraging results 
HIV (Ongoing Project- Development of edible vaccine using
transgenic plants (HIV antigen into Tomatoes) funded by
Agriculture research service of the U.S department of
Agriculture which is ISTC partner project #2176)
1) Preventing infectious disease, Autoimmune disease,
2) Administration of edible vaccine to mothers might be
successful in immunizing fetus in utero by
transplacental transfer antibodies
3) The edible vaccine used in following disease
1) Biotechnology expanding horizon by- B.D. Singh ,pp515-517.
2) Indian journal of biotechnology vol-7, july 2008,pp283-294.
3) P Lal et al, edible vaccines: current status and future, Indian journal of medical
microbiology, (2007) 25 (2):93-102.
4) I. Potrykus, Annu. Rev. Plant Phvsiol. Plant Mol. Bioi.1991. 42:205-225
5) Neeraj Mishra et al, Edible vaccine:A new approach to oral immunization, Indian
journal of biotechnology,Vol 7, july 2008, pp 283-294.
6) Ma, S.-W., Zhao, D. L., Yin, Z. Q., Mukherjee, R., Singh, B., Quin, H. Y., Stiller, C.
R. and Jevnikar, A. M., Nature Med., 1997, 3, 793–796
7) V. M.Waghulkar, Fruit Derived Edible Vaccines: Natural Way For The Vaccination,
International Journal of PharmTech Research Vol.2, No.3,julu-sep. 2010, pp 2124-
8) Arakawa T, Chong DK, Langridge WH. Efficacy of a food Plant-based oral cholera
toxin B subunit vaccine. Nat Biotechnology 1998;16(3):292–7. 05.Giddings G,
Allison G, Brooks D, Carter A. Transgenic plants as factories for biopharmaceuticals.
Nat Biotechnol 2000; 18(11):1151–5.
9) Mason HS, et al. (2002). Edible plant vaccines: applications for prophylactic and
therapeutic molecular medicine. Trends Mol. Med. 8:324-329.
10) Ruf S, et al. (2001). Stable genetic transformation of tomato plastids and expression of
a foreign protein in fruit. Nat. Biotechnol. 19:870-875.
11) Ongoing Project- Development of edible vaccine using transgenic plants (HIV antigen
into Tomatoes) funded by Agriculture research service of the U.S department of
Agriculture which is ISTC partner project #2176 http://www.istc.ru
12) Mason H. S. et al. (1992). Expression of Hepatitis B surface antigen in transgenic
plants, Proct Natl Acad Sci USA, pp- 11745-11749
13) Mason H. S. et al. (1996). Expression of Norwalk virus capsid protein in transgenic
potato and tomato plants and its oral immunogenisity in mice, Proct Natl Acad Sci
USA, pp- 5335-5340
14) Yusibev V. et al.(2002) Expression implants and immunogenisity of plant virus based
experimental rabies vaccine, vaccine, 20, pp-3155-3164