This morning at the conference, Charles Arntzen from Arizona State University talked about transforming plants into little green vaccine-manufacturing machines using engineered viruses. He helped pioneer the technique a few years ago when he made a vaccine against plague, and now he’s taken aim at norovirus, aka the “dreaded cruise ship virus”, which can hamstring people for a day or two with diarrhea and vomiting.

The disease may not seem like the worthiest target of vaccination efforts — especially compared with the last big vaccine produced by this technology, which targeted cancer. But in a way, that’s the point. Pharmaceutical companies aren’t going to waste their time with something that’s elective and only lasts a couple days, and cruise-goers don’t inspire much sympathy in disease-fighting philanthropists, so this technique provides a cheap and easy way to fill in the gap. And to be fair, “cruise ship virus” can also cause outbreaks in more heartrending locations, like hospitals, day care centers, homes for the elderly and, allegedly, football teams.

To get the tobacco plants to produce the vaccine, researchers insert genes coding for virus structural proteins into the tobacco mosaic virus, and infect plants with the engineered strain. The virus replicates and spreads through the plants, making the plant cells churn out the encoded particles, which can be used in vaccines.

The use of recombinant virus is an improvement over the more common method for producing plant vaccines, which uses transgenic plants and so is slower and generates a lower yield. (Arntzen has also been involved with that technology since its early days.)

More importantly, the recombinant virus approach has significant advantages over the traditional flu vaccine manufacturing technique, which uses chicken eggs and has been more or less unchanged for decades. Plant-generated vaccines don’t involve any viral genetic material so they’re noninfectious, can be scaled up easily and cheaply, and in some cases patients can vaccinate themselves simply by eating the plant.

Image: Flickr/richardmasoner

This morning at the conference, Charles Arntzen from Arizona State University talked about transforming plants into little green vaccine-manufacturing machines using engineered viruses. He helped pioneer the technique a few years ago when he made a vaccine against plague, and now he’s taken aim at norovirus, aka the “dreaded cruise ship virus”, which can hamstring people for a day or two with diarrhea and vomiting.

The disease may not seem like the worthiest target of vaccination efforts — especially compared with the last big vaccine produced by this technology, which targeted cancer. But in a way, that’s the point. Pharmaceutical companies aren’t going to waste their time with something that’s elective and only lasts a couple days, and cruise-goers don’t inspire much sympathy in disease-fighting philanthropists, so this technique provides a cheap and easy way to fill in the gap. And to be fair, “cruise ship virus” can also cause outbreaks in more heartrending locations, like hospitals, day care centers, homes for the elderly and, allegedly, football teams.

To get the tobacco plants to produce the vaccine, researchers insert genes coding for virus structural proteins into the tobacco mosaic virus, and infect plants with the engineered strain. The virus replicates and spreads through the plants, making the plant cells churn out the encoded particles, which can be used in vaccines.

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