标题: [英语,新闻]Potato-grown Hepatitis B vaccine pill [打印本页] 作者: StephenW 时间: 2011-4-25 11:04 标题: [英语,新闻]Potato-grown Hepatitis B vaccine pill
DELAVAN — Outside, it was a chilly, damp April morning. Nothing much was growing in the industrial park on Delavan’s east side.
Inside, however, the weather was sunny and bright and plants were bursting into life.
They looked like plain, boring potato plants, although the bright green leaves were a pleasant sight this time of year.
But these potatoes are like no others in the world.
They make medicine.
Bob Britt beamed as he took guests into the laboratory at PlantPharm BioMed on Woolsey Street in Delavan.
“This is the farm of the future,” Britt said.
In other words, it is “the world’s leader in plant-derived biomanufacturing.”
That’s the business of using living tissue to make medicine. Most often, companies use yeasts, insects, fish or mammalian tissue, according to PlantPharm literature.
Britt has worked in agribusiness for 35 years, mostly in the hybrid seed business. Today, his job is a hybrid—commercial agriculture married the pharmaceutical industry.
“We formed PlantPharm specifically for taking the product into the marketplace,” Britt said. “We already know what we’re doing on the agriculture end.”
Britt and his partners at PlantPharm have genetically engineered the plants to create the hepatitis B vaccine. The production method will make a cheaper, more stable hepatitis B vaccine than is available on the market, and the Delavan company is poised to be the first to make it happen, Britt said. How it works
Britt said he’s using plant tissues to replicate a vaccine. He and his partners have been working on perfecting the process since 1998 and have had to work through a lot of challenges.
They started with a genetically modified potato plant that was guaranteed free of diseases and engineered to grow quickly.
Genetic engineering is the science of replacing or adding a gene to an organism’s genetic code, Britt said.
The PlantPharm team started “knocking out genes” and replacing them—one at a time—with a gene that creates a protein that produces the hepatitis B vaccine.
Each change had to be tested because each had a potentially unpredictable effect on the way the plant grew, Britt said.
Another challenge was one any gardener is familiar with: the weather.
Other companies that have tried growing plants for pharmaceutical use did so outdoors in fields, Britt said. But the weather is too unpredictable, and it’s too hard to keep the sensitive material safe, he said.
“You don’t want a raccoon running off with a cutting and planting it in your garden,” Britt said.
To combat the unpredictability of weather and raccoons, Britt and his son Barrett designed an indoor growing system. Flats of potato cuttings grow inside stacks of clinical cabinets built by PlantPharm employees. A computer controls the temperature, the lights and the moisture inside the cabinets. Lights flash to warn Britt of any sudden changes in the “weather.”
PlantPharm can harvest as many as six crops a year, according to company literature.
The enclosed environment not only provides optimum growing conditions but also keeps the modified plants enclosed so they don’t mingle with nonengineered plants, the literature states.
Plants are a good medium for producing pharmaceuticals as opposed to using mammalian tissues, Britt said, because plants don’t transmit diseases to humans. Plants grow faster than animals, and it’s much less expensive to screen plants for high yields than it is to screen cattle, he said. What’s next
In clinical trials, humans who have eaten the raw potatoes have then developed the hepatitis B antibodies. That means the potatoes accurately produced the vaccine, Britt said.
Potatoes don’t make good vaccine delivery systems, however.
Eating a potato wouldn’t deliver an accurate does of vaccine, Britt said.
That’s where the pharmaceutical experts come in.
Next, Britt and his team will reduce the potato material into pills and enter into the clinical test phase required by the U.S. Food and Drug Administration.
The potato-grown pills would change the market, according to material PlantPharm BioMed prepared for potential investors.
A vaccine in pill form would be easier to store and transport than injected vaccines that must be refrigerated, Britt said. Pills also would have a longer shelf life than injectable vaccines, he said.
PlantPharm will be the first company to create an oral hepatitis B vaccine, as far as Britt is aware. He is amazed where his career that started in agriculture education and then seed sales has ended up.
“Who would have thought you could get agriculture into pharmaceuticals?” Britt said. WHAT IS HEPATITIS B?
Hepatitis B is a liver disease that usually is not fatal in healthy adults. The disease can be chronic, however, and can lead to serious liver damage, according to the national nonprofit hepatitis B Foundation.
The disease is transmitted sexually, by the use of contaminated needles or from mother to child.
Worldwide, 2 billion people have been infected with hepatitis B, according to data from the foundation. Of those, 400 million people have become chronically infected, which means they are unable to get rid of the virus.
In China alone, 500,000 people die each year from hepatitis B, according to PlantPharm BioMed research. The country now requires babies to be vaccinated for the disease, which creates a demand for 51,000 vaccine doses each year.
In India, 1 million of the 25 million babies born every year run the risk of developing chronic hepatitis B. Published at: http://www.GazetteXtra.com/news/2011/apr/24/delavan-company-produces-medicinal-potatoes/作者: StephenW 时间: 2011-4-25 11:06