Enter your email to receive our weekly newsletter. But soon children and adults alike could receive vaccines from corn puffs or a jar of baby food. Barriers to immunization in poor countries include the cost of vaccines and needles, lack of health-care workers and difficulty in refrigerating the doses. And simple food processing like drying and grinding could create nonperishable preparations.
Researchers isolate the gene for a protein on the surface of a virus.
The viral gene is inserted into DNA from Agrobacterium , a bacterium that infects plants, and the hybrid DNA is put back into the bacterium. Mixed with injured tissue from corn plants, Agrobacterium injects the plant cells with its DNA, which is incorporated into the cells' chromosomes. Scientists use these cells to create seedlings that will produce the viral protein in the corn kernels of the adult plants. ProdiGene creates its vaccines by genetically engineering corn to produce bacterial or viral proteins that elicit immune responses when eaten. Last year, the company received a patent covering any viral vaccine produced in any plant.