Edible vaccines

Edible Vaccines Plant Based Organic And Economical Vaccines
For Treatment and Cure Of The Diseases.

1. EDIBLE VACCINES Name :- Bhadani Smit Ramjibhai Roll No .:- 17BPH095 Batch :- E Program :- B. Pharm Sem .:-IV Subject :- Pharmacognosy and Phytochemistry-1

2. CONTENTS Introduction To Vaccines Ideal Vaccine Introduction To Edible Vaccines Concept Of Edible Vaccine Why Edible Vaccines Are Used ? Mechanism Of Action Methods For Transformation Of DNA/Gene Into Plants Candidates For Edible Vaccines Examples Of Edible Vaccines Consideration Factors/Factors Affecting Efficacy Of Edible Vaccines Application Limitations Regulatory Aspects/Issues Recent Discoveries Advantages & Disadvantages Future Aspects

3. IDEAL VACCINE It should not be toxic or pathogenic. Low levels of side effect. Long lasting humoral and cellular immunities. It should not contaminate the environment. It should not cause problems in individual. Technique of vaccination should be simple. It should be cheap.

4. VACCINES A vaccine is a biological preparation that improves immunity to a particular disease. It contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbes, its toxins or one of its surface proteins. The process of distributing and administrating vaccines is referred to as vaccination. Vaccination is a form of immunization . Routes of administration, including oral, nasal, intramuscular, subcutaneous, and intradermal. VACCINES PROPHYLACTIC ( e.g. to prevent the effects of a future THERAPEUTIC infection by any (e.g. vaccines against Natural or “ wild” cancer). pathogen )

5. EDIBLE VACCINES A genetically manipulated food, containing organisms or related antigens that may provide active immunity against infection. In the edible vaccines Transgenic plants are used as vaccine production systems. The genes encoding antigens of bacterial and viral pathogens can be expressed in the plants in a form in which they retain native immunogenic properties. Initially thought to be useful only for preventing infectious diseases, it has to be found application in prevention of autoimmune diseases, birth control, cancer therapy, etc. Edible vaccines are currently being developed for a number of human and animal diseases. As Hippocrates said, Let “ thy food be thy medicine”.

6. CONCEPT OF EDIBLE VACCINES Developed by Arntzen in the 1990s. Introduce gene of interest into plants (Transformation ) Gene expressed in the plant tissues edible parts (Transgenic plants) Genes encode putatively protective vaccine antigens form viral, bacterial, and parasitic pathogens that cause disease in humans and animals Ingestion of the edible part of the transgenic plant (oral delivery of vaccines).

7. WHY EDIBLE VACCINES USED ? NEEDLE FREE C H E AP S T O R AGE S A F E Oral vaccines provide “mucosal immunity” at various sites by secreting antibodies. Don’t need to worry about re-use, misuse and lack of sterilization. Thus, low risk of infection . Estimated cost of $0.005 to grow antigen for one dose of hepatitis B vaccine in an unprocessed form. Administering oral vaccines would require little or no training at all. Heat-stable; do not require cold-chain maintaince. If the local/native crop of a particular area is engineered to produce the vaccine, then the need for transportation and distribution can be eliminated.

8. MECHANISM OF ACTION The goal of oral vaccination is to stimulate the mucosal and systemic immunity against pathogen . Edible vaccine when taken orally undergoes the mastication process and the majority of plant cell degradation occur in the intestine as a result of action of digestive or bacterial enzyme on edible vaccine . Peyer’s patches (PP) are an enriched source of IgA producing plasma cells and have the potential to populate mucosal tissue and serves as mucosal immune effector site. The breakdown of edible near PP, consisting of the 30-40 lymphoid nodules on the outer surface of intestine and contain follicles. These follicles act as the site from which antigen penetrates the intestinal epithelium, thereby accumulating antigen within organized lymphoid structure. The antigen then comes in contact with M-cell. M -cell passes the antigen to macrophages and B-cell.

9. HOW EDIBLE VACCINES PROVIDE PROTECTION

10. METHODS FOR TRANSFORMATION OF GENES INTO PLANTS STABLE INTEGRATION TRANSIENT EXPRESSION ELECTRO P O R A TI ON VECTOR CARRIER METHOD M I C ROPR O JE C T IL E BOMBARDMENT METHOD CHIMERIC VIRUSES

11. PLASMID/VECTOR CARRIER SYSTEM : Agrobacterium Tumifaciens METHOD

12. MICRO PROJECTILE BOMBARDMENT/GENE Selected DNA sequences are precipitated onto metal (e.g. Gold, tungsten) particle Bombarded against the vegetable tissue with a particle gun at an accelerated speed Micro-particles penetrate the walls and release the exogenous DNA inside the cell where it will be integrated in the nuclear genome Produce large number of genetically identical crop

13. MICRO PROJECTILE BOMBARDMENT/GENE c

14. CHIMERIC VIRUSES METHOD

15. ELECTRO- PORATION Introduction of DNA into cells by exposing them for brief period to high voltage electrical pulse which is thought to induce transient pores in the plasma lemma . The cell wall presents an effective barrier to DNA. Therefore, it has to be weakened by mild enzymatic treatment so as to allow the entry of DNA into cell cytoplasm.

16. FACTORS AFFECTING EFFICACY OF EDIBLE VACCINES FACTORS AFFECTING EDIBLE VACCINES Antigen selection (safe, suitable, stable) Efficacy in model systems (small qty.) Choice of plant species (suitable, easy grown, storage, cost) Delivery and dosing issues Safety issues (allergic & toxic potential) Public perceptions and attitudes to genetic modification Quality control and licensing (consistent)

17. CANDIDATE PLANTS BANANA POTATO TOMATO RICE MAIZE TOBACCO WHEAT CARROT

18. EXAMPLES OF EDIBLE VACCINES

19. APPLICATIONS Cancer Therapy. Birth Control. Chloroplast Transformation. Role In Auto Immune Disease. Recombinant Drugs/Proteins.

20. LIMITATIONS Individual may develop immune tolerance to the particular vaccine protein or peptide. Dosage required varies from generation to generation and plant to plant ,protein content, patent’s age, weight. They are prone to get microbial infestations. Selection of best plant is difficult. It’s function can be hampered due to vast difference in the glycosylation pattern of plants and humans.

21. LIMITATIONS They are dependent on plant stability as certain foods cannot be eaten raw ( e.g . Potato) and needs cooking that cause denaturation or weaken protein present . Proper demarcation line is necessary between ‘ vaccine fruit ’ and ‘normal fruit’ to avoid misadministration of vaccines.

22. REGULATORY ASPECTS It has to be decided whether edible vaccines would be regulated under food, drugs or agricultural products . Undecided that licensing shall be required for the antigen or genetically engineered fruit or transgenic seeds. Transgenes may spread by pollen, sucking insects, transfer to soil microbes during plant wounding or breakdown of roots and may pollute surface and ground water. Ethical considerations usually restrict clinical trials from directly assessing protection in humans.

23. ADVANTAGES Do not require administration by injection. Possible production of vaccines with low costs. Do not require separation and purification of vaccines from plant materials. Necessary syringe & needles not required. Economical in mass production and transportation. Heat stable, eliminating the need for refrigeration.

24. DISADVANTAGES Development of immune tolerance to vaccine peptide or protein. Consistency of dosage from fruit-to-fruit, plant-to-plant and generation- to - generation 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.

25. RECENT DISCOVERIES Scientists Create Edible Honeybee Vaccine To Protect Them From Diseases:- “The first ever vaccine for insects now exists. Scientists at University of Helsinki in Finland hoping to save honeybee worked on it. This Edible vaccine protects the bees against American foulbrood(a bacterial disease caused by spore-forming Paenibacillus larvae ssp.Larvae. This will help to protect the global food production honeybees.” - 1 st January,2019

26. NATURAL COMPOUNDS FIGHT AGAINST ZIKA AND DENGUE VIRUS “National University Singapore have discovered that many edible plants contain natural compounds that can protect us from Zika and Dengue virus. The university said that many natural compounds can disrupt the replication machinery of both zika and dengue virus. They are present in foods like tea, red onion, yellow ginger and grapes. In future the research team plans to test this vaccine .” -5 th October,2018

27. F U T U RE ASPECTS Edible vaccine holds a great potential. It reduces the cost of transportation and refrigeration. It neglect the needle and complicated way of vaccine administration . For many disease the research in going on in many countries funded by their government or industry. Significant challenges are still to be overcome before vaccine crop can become a reality. There are some safety concerns which need to be overcome in near future. In another concern, scientists need to be sure that vaccines meant to enhance immune response do not backfire and suppress immunity instead.