Hematech, Inc., a biotechnology company based in Sioux Falls, SD, announced that it has genetically engineered cattle that may be immune to bovine spongiform encephalopathy (BSE) or mad cow disease. In humans, a condition known as variant Creutzfeldt-Jakob disease (vCJD) is a degenerative and fatal brain disorder associated with eating the contaminated meat from cows infected by BSE. Prions, misshapen proteins in the brain, are believed to cause mad cow disease in animals and vCJD in humans.
Hematech, Inc., is owned by the pharmaceutical division of the Japanese Kirin Brewery Company, Ltd. The company’s scientists used a genetically manufactured cell line in which the gene responsible for prion production is disabled. From these cells, 12 bulls were cloned, all prion free. When researchers took brain cells from the engineered cattle and mixed them with prions in a test tube, the cattle brain cells did not become misshapen.
“That’s a pretty good indication that they will not be able to contract the disease, nor would they be able to pass the disease on,” said James Robl, PhD, Chief Scientific Officer and President of Hematech, Inc.
The bulls are now two years old and appear to be developing normally. The next step is to inject some of the bulls with BSE-infected brain cells. Scientists will monitor the animals during the next 18 months to see if they develop mad cow disease.
Although currently not intended for human consumption, the cattle, if they prove to be mad cow-resistant, could eventually be used as a source of vCJD-free blood serum or in pharmaceutical manufacturing.
The research, “Production of Cattle Lacking Prion Protein,” was reported in the online edition of the journal Nature Biotechnology on December 31, 2006.
Source: USA Today (online), January 1, 2007