Researchers at Loma Linda University Medical Center are developing strains of tomatoes and potatoes they hope will eventually be used to provide immunization against cholera, rotavirus, and enterotoxigenic E. coli, better known as “traveler’s diarrhea.”  In laboratory trials, the scientists have successfully immunized mice against the cholera toxin and rotavirus by feeding the animals with raw potato from the genetically altered plant.

Biochemistry professor Dr. William Langridge, who heads up the research project, says that the use of plants to generate and deliver vaccines has the potential to revolutionize vaccination programs both in developing and industrialized countries.  But he says the most dramatic impact would be felt in “those areas of the developing world where more than 3 million people, mainly children, die annually from diarrhea-causing diseases.” Langridge points out that inadequate water supplies and the lack of access to medical treatment mean that dehydration from rotavirus diarrhea kills a far greater number of people than cholera, which is usually considered more lethal.

Langridge says that using genetically altered vegetables to deliver vaccines overcomes a number of problems associated with coordinating pharmaceutical aid in poverty-stricken regions, such as inadequate supplies of vaccines and inefficient distribution methods. “Ideally, these will be crops that can be grown, harvested, and distributed locally, at minimal cost,” says Langridge.

Some of the difficulties yet to be conquered include the issue of dosage—finding ways to predict and control the immune response in humans who consume the vegetables. More laboratory tests are planned, which will be followed by pre-clinical and clinical trials within the next several years.

Langridge’s research, which he began in 1993, also has significance in other areas.  His findings have acted as a springboard for related studies into the development of plant sources that will immunize humans against what are known as “thilymphocyte mediated autoimmune diseases,” which includes Type 1 diabetes, multiple sclerosis, and rheumatoid arthritis.

Loma Linda University Medical Center, which is owned and operated by the Seventh-day Adventist Church, is renowned for its cutting-edge research and medical programs in areas ranging from infant heart transplants, to proton therapy for cancer, to corneal transplants.