Medical Device Link.

"The recent example of Germany gives you an idea of how serious this problem is in Europe," says Brad Crutchfield, general manager of the biomaterials division at Bio-Rad Inc. (Hercules, CA). "After the first case of BSE was reported in Germany in November 2000, beef consumption dropped 40 to 60% overnight."

Commonly known as mad cow disease, BSE affects the central nervous system of cattle, ultimately killing them. BSE has also been linked to a human neurological disease called new variant Creutzfeldt-Jakob disease (nvCJD), which is thought to be transmitted through consumption of BSE-infected meat. This fatal neurodegenerative condition is believed to have caused the deaths of more than 80 people in the UK and other parts of Europe.

In marked contrast to the European Union, the United States does not yet routinely test cattle for BSE.

"Currently we have no evidence of BSE in the United States, and FDA and other federal agencies are working diligently to keep it out," said Stephen Sundlof, director of FDA's Center for Veterinary Medicine. Sundlof's remarks were made in testimony before the Senate Committee on Commerce, Science, and Transportation in April of this year.

However, industry experts confirm that the U.S. Department of Agriculture (USDA) is conducting hearings to determine whether the use of such tests is warranted in the United States.

The European Union pays 15 euros ($13.30) for each BSE test kit, creating a market of 105 million euros (approximately $93 million). Some experts estimate that the demand could grow to 30 million tests, making for a market of 450 million euros (approximately $400 million). And if the United States, with an estimated 100 million cattle, decides to implement such testing, the market would increase explosively.

Despite such market potential—at least in Europe—the field of companies developing new tests is so far remarkably uncrowded. To date, the EC has approved only three diagnostic products to test for BSE in cattle. All of these tests are performed postmortem—so far there has been no successful test developed to detect BSE in live animals.

Selection of the EC's official BSE tests was based on the results of an evaluation commissioned by the EC and carried out by the Joint Research Center's Institute for Reference Materials and Measurements (Geel, Belgium). Results of the testing showed that three of the four technologies evaluated by the institute were 100% successful in identifying all infected and noninfected samples.

The first test, manufactured by Bio-Rad, is called Platelia. It detects the presence of a resistant form of protein prion (PrP) that has been linked to BSE. Platelia uses monoclonal antibodies in a standard ELISA format after the brain sample has been purified.

Another technology, a chemiluminescent ELISA, is available from Enfer Scientific Ltd. (Tipperary, Ireland).

Enfer also manufactures a supplemental test used to confirm positive results. In March of this year, Abbott Laboratories (Abbott Park, IL) signed an agreement with Enfer to market both tests in many parts of the world.

Finally, Prionics AG (Zurich, Switzerland) offers a Western blot test that detects abnormal PrP. It has a turnaround time of less than 24 hours.

The EC is currently evaluating five more tests for BSE. They are from ID-Lelystad (The Netherlands); the Imperial College of Science, Technology, and Medicine (UK); the Institute of Neurodegenerative Diseases at the University of California, San Francisco; and Perkin- Elmer Life Sciences (UK). The commission is also reviewing an ELISA version of Prionics's test.

Other companies are also developing tests for BSE (see Table). One of the more promising technologies is one that can be performed on live animals. Boehringer Ingelheim Vetmedica GmbH (Ingelheim am Rhein, Germany) is working on a test that measures the overexpression of a biological marker and a significant increase in the concentration of the cytokine interferon.

According to the company, the findings to date suggest that the process is highly sensitive—so far all animals in which BSE has been confirmed produced a positive result. The company expects to have the technical components of the test sufficiently developed by the end of this year in order to start clinical evaluations.

No tests for the detection of BSE have yet been approved for use in the United States. If USDA should require testing similar to that of Europe, however, the potential market for such tests could be staggering.

Copyright ©2001 IVD Technology