Edible Vaccines: Promises and Challenges

Abstract

Vaccines are biological preparations that improve immunity to particular diseases and form an important innovation of 19th century research. It contains a protein that resembles a disease-causing microorganism and is often made from weak or killed forms of the microbe. Vaccines are agents that stimulate the body's immune system to recognize the antigen. Now, a new form of vaccine was introduced which will have the power to mask the risk side of conventional vaccines. This type of vaccine was produced from plants which are genetically modified. In the production of edible vaccines, the gene-encoding bacterial or viral disease-causing agent can be incorporated in plants without losing its immunogenic property. The main mechanism of action of edible vaccines is to activate the systemic and mucosal immunity responses against a foreign diseasecausing organism. Edible vaccines can be produced by incorporating transgene in to the selected plant cell. At present edible vaccine are developed for veterinary and human use. But the main challenge faced by edible vaccine is its acceptance by the population so that it is necessary to make aware the society about its use and benefits. When compared to other traditional vaccines, edible vaccines are cost effective, efficient and safe. It promises a better prevention option from diseases.

Plant-based vaccines and antibodies to combat COVID-19: current status and prospects

“…26 The mechanisms involved in initiating host immunity against the pathogen are the systemic and mucosal immune responses. 26 Some vaccines are produced by direct bombardment or biolistic methods, such as the ones against cholera, Lyme disease, anthrax, tetanus, plague, rotavirus, and canine parvovirus 26,27 Vaccines produced by indirect methods or Agrobacterium-mediated gene transfer include the ones targeting tuberculosis, dengue, avian flu, and Ebola viruses. 28 Several plant-based biological products have reached clinical trials, with a few available commercially as medical devices and pharmaceuticals for the treatment of chronic and infectious diseases.…”

“…ZMapp is a drug cocktail of antibodies that conferred protection against the Ebola virus. 43 Other plant-based pharmaceutical products are insulin produced from transgenic safflower (SemBioSys) 44 or potatoes, 26 growth factor in transgenic barley, 45 taliglucerase alfa (for the treatment of Gaucher's disease) in transgenic carrot (ProtalixBio Therapeutics), 46 avian influenza vaccine in transgenic tobacco (Medicago), and Ebola vaccine in transgenic tobacco (Mapp Biopharmaceutical). 16,47,48 Potato is being used for production of vaccines against tetanus, diphtheria, hepatitis B, Norwalk virus, enteritis caused by E. coli strain, mink enteritis, and rabbit hemorrhagic virus.…”

“…16,47,48 Potato is being used for production of vaccines against tetanus, diphtheria, hepatitis B, Norwalk virus, enteritis caused by E. coli strain, mink enteritis, and rabbit hemorrhagic virus. 26,49 Rice is used for developing antibodies against E. coli. 50 Tomatoes are being used for vaccine production against SARS, Norwalk virus, Vibrio cholera, pneumonia, and bubonic plagues.…”

A cross talk between the immunization and edible vaccine: Current challenges and future prospects

“…The society should be aware of the benefits and uses of the edible vaccines. The beliefs of people in some areas are that the genetically modified plants are a threat like evil spirit and may destroy the world [ 65 ]. So, the role of the authorities is to awake people from such myths.…”

“…Better prevention options from diseases are done by an edible vaccine when they are developed in a proper manner when compared to traditional vaccines. During pollination, the genetically modified plants may enter the genetically non-modified plants and cross-contamination may occur which may lead to the aggressiveness of the genetically modified plants [ 65 ]. Hence a close and strict monitoring of the plants grown for the edible vaccine is necessary.…”