What are edible vaccines?
A vaccine is a biological preparation that stimulates the development of antibodies to produce immunity to a disease. Vaccines are most commonly delivered by injection, but some are also given by mouth or nasal spray. Both delivery and production of synthetic vaccines are complicated and costly process thus research is being done to create edible vaccines in the form of transgenic plants, which are being looked into as a possible alternative to producing and delivering vaccines.
Food vaccines, oral vaccines, subunit vaccines, and green vaccines are some of the other names for edible vaccines. They appear to be a feasible option, particularly for the impoverished and emerging nations. They have proven to be a wonderful benefit in medicinal science, and biotechnologists deserve all of the credit. Edible vaccines are based on the idea of transforming edible foods into possible vaccinations to prevent infectious diseases. It’s also used for autoimmune disease prevention, birth control, and cancer treatment, among other things. For a variety of human and animal diseases, edible vaccinations are currently being researched.
How edible vaccines are manufactured?
In recent years, biotechnologists have invented a new concept called edible vaccine. Edible vaccines are subunit vaccines in which specific genes are inserted into transgenic plants, which are subsequently encouraged to produce the encoded protein. Potatoes, bananas, lettuce, corn, soybeans, rice, and legumes are among the foods that have been subjected to this treatment. They are a simple to administer, store, and accept delivery system for patients at various ages that is also cost effective. Edible vaccinations hold the promise of drastically lowering diseases such as measles, hepatitis B, cholera, diarrhoea, and other ailments, particularly in developing countries.
Successful edible vaccines
Anti-malaria edible vaccines: Chowdhury and Bagasara presented anti-malaria edible vaccines in distinct transgenic tomato plants expressing antigenic type(s) in 2007. They hypothesised that immunising people against 2–3 antigens and each stage of the multistage parasites’ life cycle would be an effective, cost-effective, and safe method of vaccination. Tomatoes of various sizes, shapes, and colours containing various antigens would make the vaccines easily identified by laypeople.
HIV edible vaccines: Tomatoes are an intriguing choice for HIV vaccinations because, unlike other transgenic plants that carry the protein, they are edible and resistant to thermal processing, allowing them to preserve their therapeutic powers.
A US business, ProdiGene, is attempting to genetically engineer maize to include a critical protein discovered on the surface of the monkey form of HIV. According to the US National Institute of Health, this advancement brings a more effective, edible HIV vaccine closer to people.
Anthrax vaccine: The use of genetically engineered spinach in the development of an edible anthrax vaccine has also been studied. Spinach is being studied as a plant-derived, edible carrier for anthrax vaccination and the HIV-1 Tat protein (a prospective vaccine candidate).
Alzheimer’s disease edible vaccines: Scientists propose that tomatoes could be used as an Alzheimer’s disease vaccine. The goal is to genetically engineer the fruit to generate an edible vaccine that stimulates the immune system to fight the disease by attacking the harmful beta-amyloid protein that causes Alzheimer’s disease by destroying crucial connections between brain cells.
Hepatitis edible vaccines: Bananas that deliver an HBV vaccination have also been produced by researchers. In comparison to the currently available injectable vaccination, which costs $125 per dose, the banana vaccine is predicted to cost only 2 cents per dose.
Flu edible vaccination: At Iowa State University, researchers are working on a way to give pigs and humans a flu vaccine merely by eating corn or corn products. Corn vaccine is quite likely to function in humans when they eat corn, corn flakes, corn chips, tortillas, or anything else that contains corn.
Cervical cancer: Italian researchers have created a vaccination against human papillomaviruses that is both immunologically active and cost-effective (HPV). Cervical cancer is caused by HPV, which is also involved in skin, head, and neck malignancies. Cervical cancer is one of the most common cancers that leads to mortality.
Advantages of food vaccine
- method of administration that is edible.
- Medical personnel and syringes are not required.
- Injections are no longer necessary to be done in a sterile environment.
- When compared to an animal system, breeding is more cost-effective in large production.
- Administration and transportation are simple.
- Controlling the temperature in plant growing effectively maintains vaccine action.
- Pathogens and poisons are not present in therapeutic proteins.
- Storage close to the point of usage. As a result, there is no requirement for refrigeration.
- Improved safety is associated with subunit vaccines (vaccines that have not been attenuated).
- In the presence of maternal antibodies, seroconversion occurs.
- Immunity generation on a systemic and mucosal level.
- Compliance has improved (especially in children).
- Multiple antigens are delivered.
- Combination with other vaccination strategies.
- Antigens generated from plants self-assemble into oligomers and virus-like particles.
- Until now, no major side effects have been reported.
- One advantage noted by Bio-Medicine.org is that edible vaccines have a lower risk of anaphylactic side effects than injection vaccines. When compared to injection approaches that lessen anaphylaxis, they found that the edible vaccination only carries a portion of the allergen.
Disadvantages and risks
- Dosage consistency varies significantly from fruit to fruit, plant to plant, lot to lot, and generation to generation.
- The vaccine’s stability in fruit is unknown.
- The process of determining the dosage necessary is time-consuming.
- It is difficult to choose the best plant.
- Certain foods, such as potatoes, should not be consumed uncooked since heating them weakens the medicine they contain.
- It is inconvenient for infants because they may spit it out, eat a portion or all of it, and then spew it up later. It may be more practical to concentrate the vaccination into a teaspoon of baby food rather than giving it as a whole fruit.
- Because of the interaction between the vaccination and the vehicle, there is always the risk of side effects.
- People could consume either too much or too little vaccine, resulting in disease outbreaks in previously thought-to-be immune populations.
- The breakdown of protein components in the stomach due to low pH and gastric enzymes is a concern with oral vaccinations. However, by repeating the antigen exposure until immunological tolerance is achieved, the deterioration can be compensated.
- Many people are concerned about the potential of disease spread through the use of edible vaccines. A possible concern is contamination of the oral delivery mechanism.
Side effects of food vaccine
To treat deadly diseases like AIDS, hepatitis, and diarrhea, developing edible vaccines could be a high-volume, low-cost delivery approach for third-world countries. In a short trial employing genetically altered potatoes to manufacture E. coli toxin, a diarrhea-causing bacterium, researchers from the NIAID and the University of Maryland found no notable negative effects. According to the National Institutes of Health, volunteers reported no major adverse responses to genetically modified potatoes used to deliver edible vaccination toxin (NIH). According to the National Institutes of Health, 10–11 volunteers who ate raw potato bites acquired four times the antibodies against E. coli, with no apparent negative effects. [Source]