Quanterix Simoa Technology

Pat & Dennis Bender Early Dementia Diagnosis & Prognosis Fund

 

J. Dennis Bender

Office, Home & Cell Phone: 859-391-5226

5726 La Jolla Blvd. – Suite 311

La Jolla, CA 92037-7345

&

Office - 100 Riverside Pl. - Suite 303

Covington, KY 41011-5711

 

We support the development of improved diagnostic methods for the early detection and diagnosis of MCI, Alzheimer’s, vascular and other dementias, their likely prognosis, and best treatment options. We focus on the development of Bayesian-based medical-decision-support systems, comparative-effectiveness research, and the better utilization of these for the above. (After incorporating in KY as a 501(c)(3) in 2002, we dissolved that entity for a simplified form of two entirely self-financed, private philanthropies utilizing a Vanguard Charitable Trust for making annual-research-grants for early-dementia-detection and its correct differential-diagnosis and likely-prognosis. They will continue on, after I am gone, either mentally or physically. Prof. Randall Bateman is the first of our fund’s research advisors.

See: https://www.alz.org/alzheimers-dementia/research_progress/earlier-diagnosis )

 

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www.JDBender.com – EMS/eVTOL Experimental Aviation Fund (Vanguard Charitable Trust)

www.JDBender.org – Dementia Diagnosis Fund (Vanguard Charitable Trust)

 

October 4, 2023

 

Simoa^® technology has contributed to the development of highly-sensitive blood-based-biomarkers, including Aβ, Tau, pTau, glial-fibrillary-acidic-protein (GFAP), and neurofilament-light (NfL), that are associated with AD and other neurodegenerative-diseases. Dr. Nicholas Ashton has spent the last decade exploring ways to diagnose Alzheimer's-disease using different biofluid-tests.

 

“These assays are being used more-routinely in research and are now being implemented into clinical-drug-trials as well as clinical-routine to help diagnose-dementia-quicker-and-easier. . . Researchers are now evaluating the use of blood-based-biomarkers by identifying patients between 3-groups, based on 2-cutoffs so that we can confirm-the-presence-of-AD, completely-rule-out-AD, or identify those patients who would need further investigation by PETs scans or CSF analysis. This will allow many patients to be addressed in one way or another and would minimize the necessary number of expensive PET-scans and invasive-CSF-tests. . . The use of blood-based-biomarkers also opens-doors to population-wide-screening and health-monitoring in individuals over-time. It's very-plausible that we'll soon be able to diagnose-Alzheimer's-disease using a simpler method, e.g., blood-collection-from-the-finger.

 

Dr. Ashton also stresses the importance of not overlooking patients who test-negative-for-Alzheimer's-pathology but still exhibit cognitive-symptoms. There are different types of proteins that develop in the brain that cause different dementias, such as alpha-synuclein for Lewy-Body-dementia or other types of tau-pathology for frontal-temporal-dementia,” he says. “At the moment, we don't have any good tests for these disorders. This is going to be an area of future research using Simoa^® technology, where we’ll start this process again of finding candidates and developing ultrasensitive-tests for different-neurogenerative-disorders.”

 

All of this is exactly what we have been looking for!

 

Editorial Article: Ultrasensitive Immunoassay Technology Drives Blood-Based Biomarkers for Alzheimer's-Disease

Leveraging Quanterix’s Simoa^® Platform, Researchers Lay the Groundwork for Pre-Symptomatic Alzheimer's Diagnosis, Guided Treatment, and Accelerated Clinical Drug Trials

3 Oct 2023

Quanterix’s ultrasensitive digital-immunoassay-technology, Single-molecule-array (Simoa^®), is helping researchers uncover novel blood-based-biomarkers for Alzheimer’s-disease (AD) and explore their value in clinical-trials, drug-development, and patient-care.

We spoke with Dr. Nicholas Ashton, Associate Professor of Neurochemistry at the University of Gothenburg, and Dr. Milena Milutinovic, Senior Manager of Field Applications at Quanterix, to learn more about the evolving landscape of AD diagnosis and treatment, the capabilities of the Simoa^®-platform, and the impact blood-based-biomarkers could have on the early-detection and management-of-AD and other neurological-disorders.

Detecting Alzheimer’s-Disease Pathology in the Blood Alzheimer’s-disease is a complex and progressive neurodegenerative disorder that affects millions of individuals and is the leading cause of dementia worldwide. It is characterized by the accumulation of amyloid-β (Aβ) plaques and neurofibrillary-tangles composed of phosphorylated-tau (p-tau) in the brain. While these pathological-changes are known to begin decades before the onset-of-cognitive-symptoms, the clinical-diagnosis-of-AD-dementia predominantly relies on symptomatic-assessment, and a definite-diagnosis can only be confirmed through post-mortem-examination.

Advances in cerebrospinal-fluid (CSF) biomarker-measurements and neuroimaging-techniques such as positron-emission-tomography (PET) have enabled the in vivo identification of AD pathology. However, the wide adoption of these methods has been hindered by their high cost, invasiveness, and inaccessibility. In contrast, blood-based biomarkers represent a simpler, cost-effective, and less invasive means to detect AD pathology, but such markers are often present in very low abundance in the blood, making their quantification challenging.

This is where Quanterix’s Simoa^® technology has been and continues to be a game-changer. “Simoa^®, thanks to its ultra-sensitivity, is among the first technologies to allow researchers to measure the same biomarkers that are present in CSF in the blood as well,” shares Dr. Milutinovic. “Simoa’s bead-based-immunoassays are around 1,000-times-more-sensitive than conventional ELISA and enable single-molecule-counting – hence its name, which comes from single-molecule-array.”

“In recent years, using ultrasensitive-immunoassays such as Simoa^®, we’ve been able to detect-very-low-levels-of-proteins of interest that are coming from the brain into the bloodstream, including phosphorylated-tau and neurofilament-light (NfL),” explains Dr. Ashton. “These assays are being used more-routinely in research and are now being implemented into clinical-drug-trials as well as clinical-routine to help diagnose-dementia-quicker-and-easier.”

The Value of Blood Biomarkers for Alzheimer's-Disease Blood-based-biomarkers not only offer the potential to improve the diagnosis of AD but may also act as valuable tools for selecting patients for inclusion in clinical-trials. “Most drugs targeting AD are focusing on clearing-amyloid-pathology from the brain, so in order for these drugs to be successful, you only want to have individuals included in your trial that have amyloid-pathology,” explains Dr. Ashton. “We’re currently using PET-imaging and spinal-fluid-tests for trial-recruitment, but a blood-biomarker would make this much more accessible for patients across all communities and not just those that have access to high-quality-hospital-care.”

According to Dr. Ashton, interest in blood-biomarkers-for-AD has also been spurred by the emergence of anti-amyloid-therapies that may be most-effective when provided early in the disease-progression. “Several drugs have been approved in the last few years that have been shown to completely remove amyloid from the brain. The sticking-point is that the benefit to patients has been minimal, but this is beginning to get better-and-better,” he says.

“As researchers, we are aware that amyloid-accumulates in the brain decades-before-symptoms. If we have methods that can completely-clear-amyloid, then potentially the optimal-time for greatest-benefit is treat people in this ‘preclinical’-phase,” he continues. “So, some major trials are now investigating removing-amyloid in individuals that have no-symptomatic-signs; they have developing pathology in the brain but are cognitively-normal. We will know the results of those in around 3 or 4 years, and we could get to the point where we start treating people without symptoms.”

In addition to identifying patients with AD-pathology for clinical-trials, researchers are also exploring the use of blood-based-biomarkers to assess-the-efficacy-of-novel-treatments. “Blood-testing, being more-amenable to serial-measurements than CSF or imaging, could help us monitor if someone is responding to a drug or not and even help determine the drug dose or frequency of administration,” says Dr. Ashton. “We’re now using blood-biomarkers as an outcome measure, even if the clinical-signs of the patient aren't showing the same thing, to see how effective a drug is.”

“For example, as of today, there are more than 100 drug clinical trials that use NfL as a primary or secondary endpoint biomarker in clinical trials,” adds Dr. Milutinovic. “7 or 8 years-ago, no one even considered doing any kind of blood-based-testing for these kinds of biomarkers, but now, thanks to increases-in-sensitivity, there’s a huge-emphasis on liquid-biomarkers in the neurology-space.”

Ultrasensitive Biomarker Detection on an Open-Platform Dr. Ashton explains that Quanterix’s Simoa^® technology has been pivotal to this shift. “Simoa^® has been instrumental in making neurofilament-light accessible to any lab in the world, and we're going a similar way with phosphorylated-tau,” he says. “Using less-sensitive technologies, we were only able to detect individuals that had severe disease, but with Simoa^®, we’re able to detect these proteins at femtomolar-level concentrations in all individuals. This is very-important for studying individuals in the very-early-phases of a disease and longitudinal-change.”

Beyond the platform’s ultra-sensitivity, another key benefit of Simoa^® is its open-architecture, which allows researchers to create their own “homebrew” assays. “It’s a completely-open-platform, so you don't have to rely on a company to dictate which proteins you look at,” says Dr. Ashton. “That’s a major advantage, as you can create and test your own hypotheses, and hopefully develop an assay from basic research right up to clinical-utility – this is what we have done with phosphorylated-tau.”

“There are several options for users looking to develop custom assays,” adds Dr. Milutinovic. “We can develop these for customers from our own service laboratory or we can train users how to prepare their own capture and detection reagents on Simoa^®-beads or planar-array, and even do a few runs with them to help optimize-detection. All this training works toward the goal of making sure they themselves can develop in-house-ultra-sensitive-immunoassays on Simoa^®.”

Simoa® technology: Bead-Based Versus Planar Arrays Simoa^® works in a similar principle to a classical sandwich-ELISA and is available both in a bead-based-format and as a planar-array. In bead-based-Simoa^®, capture-antibodies are immobilized on paramagnetic-beads and are mixed with the sample, detection-antibodies, and an enzyme with washing-steps included after every incubation. The beads are then resuspended in a substrate and together loaded into the microarray containing over 200,000-wells, which forms a fluorescent-product in the presence-of-the-enzyme. Each well can hold only one-bead. As wells are then sealed, this setup defeats diffusion, and concentrates fluorescent signal, which when imaged, enables detection of a single-molecule. Conversely, in Simoa^®-planar-arrays, capture antibodies are spotted on the bottom of a plate in a circular-pattern, with each spot corresponding to a different-target-analyte. These arrays can achieve up to 10-plex-measurements-simultaneously without compromising on sensitivity.

Future Outlooks Both Dr. Ashton and Dr. Milutinovic believe the impact of blood-based biomarkers on Alzheimer’s-diagnosis and treatment is imminent. Where Dr. Ashton sees their greatest utility is for pre-screening in primary-care settings, where they could help to streamline-patient-stratification and enable-earlier-clinical-intervention.

“Researchers are now evaluating the use of blood-based-biomarkers by identifying patients between 3-groups, based on 2-cutoffs so that we can confirm-the-presence-of-AD, completely-rule-out-AD, or identify those patients who would need further investigation by PETs scans or CSF analysis¹,” adds Dr. Milutinovic. “This will allow many patients to be addressed in one way or another and would minimize the necessary number of expensive PET-scans and invasive-CSF-tests.”

The use of blood-based-biomarkers also opens-doors to population-wide-screening and health-monitoring in individuals over-time. “Following this year’s AAIC conference in Amsterdam, I think it's very-plausible that we'll soon be able to diagnose-Alzheimer's-disease using a simpler method, e.g., blood-collection-from-the-finger,” says Dr. Ashton. “This could be an extremely useful tool for individuals to provide blood samples from home or a primary care center and have regular checkups if they are undergoing treatment.”

Dr. Ashton also stresses the importance of not overlooking patients who test-negative-for-Alzheimer's-pathology but still exhibit cognitive-symptoms. “There are different types of proteins that develop in the brain that cause different dementias, such as alpha-synuclein for Lewy-Body-dementia or other types of tau-pathology for frontal-temporal-dementia,” he says. “At the moment, we don't have any good tests for these disorders. This is going to be an area of future research using Simoa^® technology, where we’ll start this process again of finding candidates and developing ultrasensitive-tests for different-neurogenerative-disorders.”

How to Leverage Simoa^® For both the bead-based and planar-array formats, Quanterix offers a variety of dedicated instruments that cater to varying throughput needs. For bead-based-assays, its HD-X instrument offers a fully-automated-solution capable of performing up-to-288-measurements in a single-run. Alternatively, the SR-X offers a compact and semi-automated-solution suitable for labs with lower-throughput-needs. Here, users generate immunocomplexes using specialized-washers-and-shakers before transferring these to the benchtop-SR-X-reader. Each run accommodates up to 96-measurements, and labs can accomplish 2-to-3-runs-per-day.

For planar-array-assays, the workflow closely mirrors that of the SR-X, with immunocomplexes being created on the bench using a partially-automated-workflow. Once formed, immunocomplexes are transferred to the SP-X reader, which can complete up to a 10-plex-run in less-than-10-minutes.

The Accelerator Lab For those who may not have direct access to Simoa^® technology, Quanterix’s Accelerator Lab, situated in Billerica, Massachusetts, enables customers to leverage Simoa's capabilities for sample-testing or custom-assay-development, even without owning the instrumentation themselves. Users can choose between commercially-available-reagents, custom-kits, or specific-components built with their own proprietary-antibodies.

References Brum WS, Cullen NC, Janelidze S, et al. A Two-Step Workflow Based on Plasma P-Tau-217 to Screen for Amyloid-Β-Positivity With Further Confirmatory Testing Only in Uncertain Cases [published online ahead of print, 2023 Aug 31]. Nat Aging. 2023;10.1038/s43587-023-00471-5. doi:10.1038/s43587-023-00471-5

 

[Keywords and compound-keywords (tags) are highlighted-and-hyphenated in italic-and-bold; place-names, organizations and titles are in bold; media-names put in italic.  Instead of underlining, I’ve been experimenting with hyphenating entire phrases – long-tail-keywords. This odd style was being tried to enhance generative-AI processing and ease-of-spotting items-of-interest in my specific website-achieved documents.  Now generative-AI and similar have eliminate this time-consuming distraction.]

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