The development and introduction of new vaccines to improve global public health faces many challenges, Arntzen noted. The vaccines must address the need for lower costs, oral-administration (needle-free), heat stability, and they must include combination vaccines including those that protect against diseases that occur predominantly in developing countries, he added.

Over the last decade, the team working with Arntzen has shown that a set of genes from human pathogens can be introduced into plant cells, and intact plants regenerated which "bio-manufacture" subunit vaccines consisting of the pathogen gene products. Simple feeding of the plant tissues to animals or humans results in an immune response to the subunit vaccines," Arntzen commented.

Arntzen's research focuses now on producing vaccines in tomatoes to fight human afflictions such as cholera, Norwalk Virus and hepatitis B. Norwalk Virus is a major cause of gastrointestinal infection and diarrhea. Diarrheal diseases kill at least two million people in the world each year, most of them children, Arntzen noted.

Ongoing research is focused on development of minimal processing technology, adopted from the food industry, to yield uniform doses of heat-stable vaccine for oral delivery, Arntzen said. He provided a summary on the strategies used to ensure that plants used in vaccine manufacture will not be mixed with those used in the food chain, and on the rationale for adoption of plant-derived vaccine technology in developing countries.

Arntzen was appointed the Florence Ely Nelson Presidential Endowed Chair at Arizona State University in Tempe i
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Contact: Brian Hyps
bhyps@aspb.org
301-251-0560
American Society of Plant Biologists
24-Jul-2004