Biotech expert: Genetically engineered, tobacco can save lives

Plants being used to mass-produce cheaper vaccines that will better protect against various diseases.

By JUDY SIEGEL-ITZKOVICH
tobacco 88 (photo credit: )
tobacco 88
(photo credit: )
Instead of killing people, tobacco plants are being used to mass-produce cheaper vaccines that will better protect against hepatitis B and cervical cancer, halt gastroenterological norovirus infections and - in the future - even improve the treatment of non-Hodgkin's lymphoma and other cancers, as well as Parkinson's and Alzheimer's disease. So says Arizona State University Prof. Charles Arntzen, a pioneer in biotechnology and the genetic engineering of plants to trigger an effective immune response in humans and animals, who received an honorary doctorate from the Hebrew University of Jerusalem Sunday night. Arntzen, who has been here five times and collaborates on projects with his Israeli (especially Hebrew University) counterparts, previously worked with raw potatoes and bananas to boost production of vaccine for poultry and humans, but he has found tobacco is much more effective, practical and cheaper to produce. His team injects viral vectors based on tobacco mosaic virus into the leaves of tobacco plants using a syringe. Five to 15 days later, they harvest that part of the leaf to see if the vectors produce a vaccine antigen. "When we get a good vector, we scale it up by growing pallets of tobacco plants and dip them into a bath of the plant virus vectors. The plants are put in a growth chamber to allow the antigen to be expressed by the virus," he told The Jerusalem Post in an interview Sunday at Jerusalem's King David Hotel. This is a much quicker and more efficient process than culturing dangerous viruses in the lab and then weakening or killing them to produce vaccines. For the team's vaccine against norovirus - which affects people of all ages, is transmitted by food or water contaminated with excrement and is responsible for most of the world's gastroenteritis infections - two weeks are required for the antigen to develop. The tobacco leaves are ground up and the cells purified through a filter - leaving out all the deadly alkaloid ingredients in tobacco. It can then be administered via nasal spray to halt the infection. As it does not give lifelong protection, pharmaceutical companies are very interested in such a plant-based vaccine because it offers a long-term, profitable mass market. Other vaccines produced quickly and cheaply in tobacco leaves will be able to replace antibiotics and keep poultry healthy until they're slaughtered, Arntzen said. It needs only be sprayed onto chicken feed and eaten to protect from infections. The plant technology is also being used experimentally to produce a customized vaccine for patients with non-Hodkin's lymphoma - a cancer of the lymph glands - to halt the progression of the disease. As tobacco plants can be used quickly to produce a vaccine based on the patient's own immune system, he said, it can stimulate the patient's immune system to fight the disease more effectively. While not all injectable vaccines will be replaced by vaccines in oral or nasal sprays, Arntzen said that many will, as new ones will be developed in the future to get the immune system to fight the progression of chronic diseases in the body. The full interview with Prof. Charles Arntzen will appear on the Health Page on Sunday, June 15.