Munich

German biologists and veterinarians are preparing to launch a coordinated investigation into prion-based diseases, which include bovine spongiform encephalopathy (BSE), or mad cow disease.

At a government-sponsored meeting in Munich on 20 July, researchers met to determine questions that should be asked and the necessary tools for studying these diseases, of which Germany has little direct experience.

Because Germany was thought to be free of BSE, German research on the diseases, known collectively as transmissible spongiform encephalopathies (TSEs), figured little during the 1990s.

But since the first cases were discovered there last year (see Nature 408, 506; 2000), sources of research funding have been springing up. Sponsors include consumer-protection and research agencies at both state and federal level. Earlier this year, for example, three states earmarked special research funds for prion-based diseases. In May the federal government allocated DM27 million (US$12 million) to such research.

A significant part of the federal funding will support a “research platform” to coordinate the mushrooming research and provide infected material for study.

Research model: Martin Groschup wants to harmonize German and French efforts on BSE. Credit: EPA

“So much has been happening so fast that it is hard to follow — and coordinate with — initiatives in other parts of Germany,” says Hans Kretzschmar, a neuropathologist at the Ludwig Maximilian University of Munich.

Aside from sponsoring meetings such as last month's, the government will create a web-page repository for results and resources, including material from a federally funded pathogenesis study due to begin at the end of the year. The study will be based at the new Institute for Emerging and Unconventional Infectious Agents on the remote Baltic island of Riems, north of Greifswald, where 50 cattle will be deliberately infected with BSE. As TSE research increases, “German scientists will need a more direct supply of infected tissue”, explains Martin Groschup, a veterinary virologist at the Federal Research Centre for Virus Diseases of Animals in Tübingen, who heads the pathogenesis programme.

Regular samples of biological fluids, including blood, cerebrospinal fluid and urine, will be taken from the cattle, and a small number will be slaughtered every few months for complete dissection. The tissues will be distributed to TSE researchers.

Groschup hopes to harmonize the programme with a similar exercise being proposed in France. If the French programme materializes, he says, “we want the innoculum and procedures to be standardized so that results from research on the materials are truly comparable.”

Hans Kretzschmar says prion research is worthwhile. Credit: EPA

Kretzschmar and Groschup are spearheading the TSE research programme in Bavaria, which, with DM20 million of funding over two years, is Germany's largest such state programme. Bavaria is also building a DM38-million TSE research centre in Munich for work on infected animals, particularly mice. Two other states, Baden-Württemberg and Niedersachsen, have smaller programmes of their own.

The upsurge in funding has raised eyebrows among health researchers specializing in more common diseases. The human TSE — variant Creutzfeldt–Jakob disease (vCJD) — has so far claimed only around 100 victims, none of them in Germany.

“CJD is not a big health hazard, but it is worth funding generously,” says Kretzschmar. This is not just because it raises hopes of curing a rare disease, he argues, but also because it feeds into research on neurodegenerative diseases generally, which usually involve amyloid proteins. “The only difference between these diseases and diseases such as Alzheimer's is that TSEs are transmissible,” he says.

One of the Bavarian projects involves screening chemical libraries for their ability to prevent prion proteins from aggregating, using a new screen that tracks the diffusion time of a single fluorescently tagged prion molecule. This work will be done by academics because, says Kretzschmar, “the pharmaceutical industry is not interested in finding cures for vCJD because it is so rare”.

Another project is to create genetically modified cattle that lack the gene for the prion protein PrP, and which therefore cannot contract BSE.