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Lone Wolf Tackles Mad Cow

September 30, 2004

Heather Heilman
Phone: (504) 865-5714

hheilman@tulane.edu

Back when Frank Bastian was a young researcher at the National Institutes of Health, doing groundbreaking work on herpes, it seemed that he had every reason to hope for a long, interesting career full of engaging, well-received work and the accolades of his colleagues in the scientific community.

madcowHe got the interesting career full of engaging work. He's probably the world's foremost expert on spiroplasma, a type of tough, motile bacteria that lacks cell walls.

But he's also become a lonely voice of dissent against one of the prevailing orthodoxies in neuropathology. After his term at the NIH, Bastian joined the pathology department at Baylor University.

Shortly after he got there, he obtained a brain biopsy of a patient who presented with symptoms of Creutzfeldt-Jacob disease (CJD).

"I started scanning sections of tissue looking for anything out of the ordinary that was the right size and lo and behold, I found something," said Bastian, now a professor of pathology at Tulane.

What he found was a spiroplasma, a type of bacteria that had only just been described in the early 1970s. He published his findings in 1979. CJD is one of a group of rather mysterious diseases that includes mad cow disease, scrapie, chronic wasting disease, and others.

They're known as transmissible spongiform encephalopathies (TSE) and are common in animals. They all cause a fatal degeneration of brain tissue. But what exactly causes them is still unknown. They have been found to be infectious diseases with a long incubation period. Whatever the infectious agent is, it's pretty hardy. It can withstand fairly extreme temperatures, and it's persistent. You can remove scrapie-infected sheep from a field, allow it to sit empty for years, but if you later put healthy sheep into the field they will come down with the disease.

By using filters, researchers were able to figure out the size of the agent. But beyond that, progress has been frustratingly slow. Around the same time that Bastian was discovering spiroplasma in the brain tissue of his CJD patient, a neurologist at the University of California-San Francisco named Stanley Prusiner was developing his own radical theory about what were then known as slow virus diseases.

Prusiner posited that prions, a name and a concept of his own invention, were the cause of the disease. Prions are misshapen and apparently spontaneously selfreplicating proteins. No one has been able to explain how a protein with no DNA could replicate itself. But no one could seem to find an alternative agent, either. Prusiner's theory won favor in the scientific community. He attracted large research grants and won the Nobel Prize in 1997.

In the meantime, Bastian was learning more about the bacteria spiroplasma. They had first been discovered in rabbit ticks. When researchers ground up the ticks and innoculated them into mice, they produced a brain infection. They were found to survive in soil for up to 17 years, tolerate a wide range of temperatures and to be resistant to traditional disinfectants. They are found in the hemalymph systems of almost all insects.

Bastian discovered that scrapie antibodies react when exposed to spiroplasma proteins. He found spiroplasma DNA in the brains of scrapie-infected sheep, in the brains of deer infected with chronic wasting disease and in human brains infected with CJD. It is not present in normal brains. More recently, he found that patients infected with CJD produce antibodies against spiroplasma.

According to Bastian, this is evidence that his theory works in practice, and he is using it as a basis for a test for the diseases, a vaccine and possibly a treatment. In addition, researchers in Japan have shown that bacteria can interact with prions in a way that suggests that prions are receptors that play a role in the disease process but are not the cause.

Because cases of transmissible spongiform encephalopathies are increasing in animal populations in Europe and North America and pose a growing threat to humans, Bastian believes it is a mistake to allow researchers working on the existing prion theory a near monopoly on research dollars in the field. Several years ago he testified before Congress, asking for more funding for research outside of the prion paradigm. His words were not taken as seriously as he would have liked, but his current work is being supported by an NIH grant.

Bastian brought his work to Tulane three years ago, motivated by a desire to return to New Orleans, which is home to his wife. Since then he's been pleased with the support he's found at Tulane and the help from colleagues in other departments. He thinks Tulane contains the expertise and the resources necessary to develop a test and vaccine for TSE, which could potentially be a great credit to Tulane.

"It's exciting," said Bastian. "I'm glad to have this goal. It's a big Project--development of a vaccine would be a huge accomplishment."

Citation information:

Page accessed: Wednesday, August 20, 2014
Page URL: http://tulane.edu/news/releases/archive/2004/lone_wolf_tackles_mad_cow.cfm

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