The USF scientists say their findings on how immune system cells attack the brain could lead to a preventive medicine.
By WES ALLISON
© St. Petersburg Times, published December 17, 1999
TAMPA -- Researchers at the University of South Florida believe they have discovered how the immune system attacks the brain in Alzheimer's disease, and they suggested Thursday their findings may lead to a drug to prevent it.
Their report, published in today's issue of the journal Science, culminates two years of study in mice at USF's Roskamp Institute. The authors contend it provides a key focus for further research by illustrating how cells that normally protect the brain instead attack it when someone has Alzheimer's.
"We've found the ignition," said Dr. Michael Mullan, director of the Roskamp Institute. "Maybe we can interfere with the process (of Alzheimer's) much earlier than we thought."
At best, any sort of preventive medicine stemming from this research is probably four or five years away, the authors acknowledged. The findings also are not expected to directly help those who already have the degenerative disease, which causes dementia and memory loss in up to 4-million Americans.
Several national leaders in Alzheimer's research declined to discuss the USF study until they could review it in full. But one who received an advance copy, Dr. William Thies of the national Alzheimer's Association in Chicago, said the report is most exciting when taken in context with all the current Alzheimer's research.
"The more papers like this that are published, the more rapidly we are going to spin off (drugs)" for treatment or prevention, said Thies, the organization's vice president for medical and scientific issues.
"The importance of this particular paper probably only gets told in history."
Scientists have long believed that immune system cells in the brain, called microglia, are somehow incensed to attack the neurons in Alzheimer's patients, but they haven't known exactly why. In mice, the USF team found, a common protein called CD40 helps tell the cells to attack.
If this proves true in people, then scientists may be able to find a chemical that will interrupt that process and prevent the damage. Roskamp researcher Terrence Town, who helped write the paper, said it's possible other scientists studying the protein already may have found one.
"This is definitely a new hope," Town said. "It opens up a large area of previously unrecognized therapy, because now we're targeting the immune system."
The research largely has been funded by Longboat Key philanthropist Robert Roskamp. Mullan and his team at the Roskamp Institute say they now hope to recruit a private drug or biotechnology firm to help develop a drug based on the new findings.
If they're successful, the people most likely to take it would be those who are genetically predisposed to Alzheimer's, or who already are elderly, Mullan said. Researchers also would have to develop better tests for detecting the earliest signs of Alzheimer's.
The key to treating any disease is finding which aspect to target, and Thies said many Alzheimer's researchers are working toward the same end.
"We will find the best site for intervention by learning as much as we can," said Thies. "Whether this is the exact site that we ought to be attacking or not, it's impossible to tell. The more sites we know about, the more likely we are to find that one."