EDIBLE VACCINES-A new approach to oral immunization

Presented by- Anurag ChandaB.Pharm 3rd Year, 6th semester18601911014

Introduction-

Plants offer enormous potential as production platform for vaccines

The stable integration of a gene into the plant nuclear or chloroplast genome can transform plants like tobacco, potato, tomato, banana into bioreactors for the production of sub-unit vaccines.

Owing to its low cost of production it is suitable for developing countries like India

Advantages-Edible means of administration.Reduced means of medical

personnel and sterile injection conditions.

Economical in mass production and transportation.

Heat stable and eliminating the use of refrigeration.

Delivery of multiple antigens.

Plant species-Potato :AdvantageEasily transformed.Easily propagated.Stored for long periods without refrigeration.DisadvantageNeed cooking which denature antigen.

BananaAdvantagesDo not need cooking.Protein not destroyed even after cooking.Inexpensive .Grown widely in developing countries.

DisadvantagesTrees take 2-3 to mature years.Spoils rapidly after ripening.

RiceAdvantagesCommonly used in baby food.High expression of antigen.

DisadvantagesGrows slowly.Requires glasshouse condition.

Tomato AdvantageGrow quickly.Cultivate broadly.High content Vitamin-A may boost immune response.DisadvantagesSpoils readily.

Oral delivery, mucosal and systemic antibody responses-

Plant derived vaccines have demonstrated the ability to induce both systemic and mucosal immune responses.

The major obstacle to oral vaccination is the digestion of the antigenic protein in the stomach.

Vaccines derived and delivered by plant cells have been shown to over come this problem through the protective effect of the plant cell wall.

A unique opportunity against the threat of bio-weapons

•A number of infectious diseases, including smallpox, anthrax, and plague have recently raised concern for their possible use in the actions of bio-terrorism.•Nations at risk are now faced with the need to be ready to vaccinate part of all their population within limited periods of time.•This means that millions of vaccine does have to be prepared, stored and renewed at intervals of time.•The economic and technical benefits offered by plant derived vaccines propose these as the ideal substitutes fro traditional vaccines.•Research on plants that produce antigens against major pathogens feared in case of bio-terrorism is already under way.

Dosage- to explain the concept of oral therapeutic protein delivery , Hepatitis B surface antigen(HBsAg) was used for oral immunization. No primary immune response was detected after two 300 microgram doses of yeast derived HBsAg. However a primary immune response began after two servings of transgenic potatoes containing, 85-300micrograms of HBsAg.Side effects- A research by National Institute Of Allergy & Infectious Diseases(NIAID), National Institute Of Health(NIH) and Maryland School Of Medicine showed no significant side effects.

Limitations-•Development of immune tolerance to vaccine peptide or protein.•Consistency of dosage from fruit to fruit and from plant to plant and from generation to generation is not similar.•Selection of best plant in difficult.•Certain foods like potato are not eaten raw and cooking the food might weaken the medicine present in it.

THANK YOU

Plant-based production of biopharmaceuticals. Rainer Fischer, Eva Stoger, Stefan Schillberg, Paul Christou and Richard M Twyman, Current Opinion in Plant Biology 2004, 152–158.

Edible vaccines: a new approach to oral immunization. Neeraj Mishra, Prem N Gupta, Kapil Khatri, amit K Goyal, Suresh P Vyas. Indian Journal Of Biotechnology.283-294.

Edible Vaccines by William H.R Langridge. Scientific American. 66-71