North Carolina State University
News Services
Campus Box 7504
Raleigh, NC 27695
(919) 515-3470
Media Contacts:
Dr. James N. Petitte, 919/515-5389 or [email protected]
Tim Lucas, News Services, 919/515-3470 or [email protected]
Karen Chapman, Origen Therapeutics, 650/827-0200
April 15, 1998
New Process Yields Pharmaceutical Proteins From Transgenic Chickens
FOR IMMEDIATE RELEASE
Most people use eggs to make omelets. North Carolina State University researcher Dr. James N. Petitte wants to use eggs to make drugs. Petitte, associate professor of developmental biology and biotechnology, is developing a process that uses early avian embryo cells to produce transgenic chickens, from which proteins can be extracted for making drugs.
"Eggs can be used for much more than food," he says. "We can use transgenic chickens to study developmental biology, to breed superior lines of livestock, and to (make) proteins for drugs in a way that is cost-effective."
To use eggs to make pharmaceutical proteins, special genes are inserted into embryonic chicken cells that have been cultured using Petitte's technology. These cells then are placed in another embryo. Later, when the chickens produce offspring, proteins can be extracted from their eggs or from their blood. The process could be a breakthrough for drug makers, since it would give them an alternative source for protein. Because many drugs are protein-based, demand for pharmaceutical proteins exceeds the supply, keeping costs high. "Chickens produce protein very efficiently," Petitte says.
NC State has been issued two patents on the technology. A third patent has been allowed and is expected to be issued soon. Origen Therapeutics Inc. of South San Francisco is the technology's exclusive licensee, and NC State has received an equity stake in Origen as partial consideration for the license.
"This technology opens the door to the rapid and accurate genetic engineering of avian species," says Karen Chapman, Origen's vice president of corporate development. "The ability to chickens-2
precisely insert or modify avian genes gives us access to the enormous potential for producing recombinant human protein pharmaceuticals in a cost-efficient manner."
Petitte's process is the only known way to make specific gene modifications in chickens. Previously, such efforts could not be targeted. By contrast, Petitte now can take chicken cells from unincubated eggs and use his special culturing method to retard the normal process of cell maturation and differentiation -- thus preserving the characteristics of young cells that make gene insertion easier. As a result, each embryo grows into a chicken whose offspring has the desired traits.
Other potential beneficiaries of the NC State technology include poultry breeders, who could use the technology as a tool in their selective breeding programs, and biomedical researchers who study developmental biology. For more than a century, these researchers have used chicken embyros to study embryo development. "We can learn a lot more about how this works from (studying) transgenic chickens," Petitte says.
Poultry producers also may benefit. Industry demand for pharmaceutical protein one day may create a specialty market for farmers, who could produce eggs specifically for drug companies instead of for human consumption.
Studies done in the 1980s, using cultured mouse embryo cells to insert genes into laboratory mice, were the inspiration for Petitte's work. He tried to adapt that concept to the reproductive physiology of chickens, and developed his method for culturing avian embryo cells as a result.
Funding for Petitte's work comes from Origen Therapeutics. Other sponsors have been the North Carolina Biotechnology Center and the U.S. Department of Agriculture.
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