By DR. DAPHNE ROBAKIS

With 5.4 million of Americans suffering from Alzheimer's disease, a proven treatment or cure remains elusive.  And the methods scientists are using to study the disease have yet to yield much in the way of understanding, much less treatment, of the disease.

But researchers at the University of California, San Diego have developed a technology using stem cells to more accurately model what goes wrong in diseased brain cells of  Alzheimer's sufferers.  Their findings will be published in this week's issue of the journal Nature.

In the study, researchers took skin cells from patients who died from Alzheimer's disease.  Then, employing newly developed stem-cell technology, they turned them into brain cells to closely replicate those found in living Alzheimer's patients. This process allows researchers to manipulate the diseased cells in the laboratory for what they hope will be a more effective way to study the disease.  In the long run, it is hoped that this research will lead to the discovery of new drugs to treat the disease.

"We developed a true human neuronal model that accurately replicates early stages of the disease in true human brain cells, " said  Larry Goldstein, professor of cellular and molecular medicine at UCSD's medical school.   This model, he said, can be used to understand how the disease works and to test drugs.   The real innovation, Goldstein said, is the development of a process to purify neurons from a mix of other cells, making it possible to grow the neurons in sufficient quantities for study.

According to Dr. Richard Caselli, a researcher at the Mayo Clinic who was not involved in the study, this research represents a "significant methodological breakthrough, and I strongly suspect we will be seeing a lot more of it being used by researchers in the future."

Dr. George Grossberg of Saint Louis University School of Medicine agrees. This "unique methodology," he said, could be used in "identifying why cells die in Alzheimer's disease, and what therapeutic interventions might be useful."

Up to now, most studies have focused on patients with the familial form of Alzheimer's disease, the type that is hereditary, which is much less common but easier to study than the sporadic form. But it is the sporadic, or non-hereditary form of the disease that accounts for 95 percent of cases.  Dr. Sam Gandy, Mount Sinai Professor of Alzheimer's Disease Research, says, "This approach is directly translatable to common forms of [Alzheimer's disease]," which is "extremely exciting stuff for scientists."

The method could also be applied to many other neurologic diseases, including Parkinson's and Lou Gehrig's disease.

Some experts, however, feel the excitement is premature, more studies are needed and the findings need to be replicated before the long-term significance of the research will be known.

"It is too soon to say how important it is or whether it will catch on generally," said Dr. Rachelle Doody, an Alzheimer's disease specialist at Baylor College of Medicine.

Most experts agree, however, in all likelihood treatments or cures derived from the research remain a long way off.