Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protein 'fingerprint' in spinal fluid could spot Alzheimer's disease

14.12.2006
23-protein screen is highly accurate and first to be validated

Scientists collaborating at Cornell University in Ithaca and Weill Cornell Medical College in New York City have identified a panel of 23 protein biomarkers in cerebrospinal fluid that acts as a neurochemical "fingerprint," which doctors might use someday to identify patients living with Alzheimer's disease.

The research will be published in the December online-edition of the journal Annals of Neurology.

Right now, physicians rely on their clinical judgment to decide whether a particular patient has Alzheimer's rather than some other form of dementia. In many cases, the diagnosis remains uncertain until brain tissue is examined at autopsy.

"Our study is the first to use sophisticated proteomic methods to hone in on a group of cerebrospinal fluid biomarkers that are specific to autopsy-proven Alzheimer's disease. Those postmortem tests confirmed that the panel is over 90 percent sensitive in identifying people with Alzheimer's disease," says Kelvin Lee, the Samuel C. and Nancy M. Fleming Professor of Molecular and Cell Biology and associate professor of chemical and biomolecular engineering at Cornell.

Researchers at a variety of centers have long sought biomarkers in blood or cerebrospinal fluid that identify the presence of Alzheimer's pathology and distinguish it from other conditions that cause dementia.

"Some of these studies have met with limited success, but most have correlated their findings with patient's clinical symptoms rather than working with the gold-standard of autopsy-proven Alzheimer's," notes Norman Relkin, M.D., associate professor of clinical neurology and neuroscience at Weill Cornell and director of the Memory Disorders Program at NewYork-Presbyterian Hospital/Weill Cornell Medical Center.

Erin Finehout, Ph.D. ‘05, the lead author on the research who had been a doctoral student in Lee's laboratory, said this has great potential to impact human health. "Typically, Alzheimer's disease is not diagnosed until the disease has already caused some amount of dementia," she said. "Having a chemical test available may allow patients to be diagnosed earlier in the course of the disease."

The Cornell study combined cutting edge "proteomics" technology, detailed image analysis, and complex computational and statistical analyses to simultaneously compare 2,000 cerebrospinal fluid proteins from 34 patients with autopsy-proven Alzheimer's disease to those of 34 age-matched controls without the disease.

"Just as the human genome reflects the array of genes a person possesses, the ‘proteome' is the vast collection of proteins expressed by those genes," said Lee. "Essentially we used high-tech methods to contrast the proteomes of Alzheimer's patients against those of a control cohort that included people with other forms of dementia as well as healthy individuals, looking for key differences between the two groups."

This effort yielded intriguing results: 23 proteins that individually might not point to Alzheimer's but together formed an identifying pattern or "fingerprint" specific to the illness.

"Although it need not have turned out that way, several of the 23 markers that emerged from this analysis proved to be proteins with known links to the pathological mechanisms of Alzheimer's disease," said Relkin.

For example, some of the biomarkers are associated with proteins that clog the brains of Alzheimer's patients. Others molecules were linked to inflammation, also a part of Alzheimer's brain pathology. Still other proteins in the panel were linked to synaptic dysfunction – the breakdown of communication between brain cells that occurs as Alzheimer's disease progresses.

"A subsequent validation group of 10 patients with suspected Alzheimer's and 18 healthy and demented control subjects turned up similar results," said Relkin. "Based on their clinical symptoms, we found the new screen to have 93 percent sensitivity to probable cases of Alzheimer's and a 90 percent accuracy in avoiding false diagnoses."

Despite their excitement over the new findings, the researchers stress that the results still need to be replicated in much larger populations.

"There's a federally funded, multicenter trial going on right now that involves many more patients, in which many enrollees will undergo spinal taps and brain imaging," Relkin said. "We hope to link into that effort to expand on these findings."

The dream of a highly accurate Alzheimer's disease test that patients and doctors could use to diagnose illness and guide treatment is the ultimate goal. But the finding has important implications for current Alzheimer's research, as well.

"You might have a promising treatment for the disease, but how can you know for sure that it's impacting on the underlying pathology, rather than just easing outward symptoms as most of the drugs that we have now do"" Relkin said.

"We are hopeful that by monitoring changes in these cerebrospinal biomarkers, we can actually track the effectiveness – or lack thereof – of experimental drugs."

He continued: "In fact, we are now using this panel to study the effects of a promising new experimental treatment for Alzheimer's called IVIg (intravenous immunoglobulin). "Data gleaned from the use of this 23-protein screen suggests that IVIg may be having a positive impact on underlying disease processes."

And while a standard test for spotting early Alzheimer's disease is not in doctors' offices today, it could be in the not-too-distant future.

"These findings speak to the practicality of using biological markers for discerning whether symptoms are reflective of Alzheimer's, another dementia or normal aging," Relkin said. "And in this study, we're offering a much more sophisticated and better-validated approach than has ever been presented before."

Blaine Friedlander | EurekAlert!
Further information:
http://www.cornell.edu

Further reports about: Alzheimer' Relkin cerebrospinal cerebrospinal fluid dementia

More articles from Life Sciences:

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

Control of molecular motion by metal-plated 3-D printed plastic pieces

27.04.2017 | Materials Sciences

Move over, Superman! NIST method sees through concrete to detect early-stage corrosion

27.04.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>