Plasma Amyloid-β 42/40 Assays Compared in Alzheimer Disease
|
By LabMedica International staff writers Posted on 14 Oct 2021 |

Image: Simoa is an ultra-sensitive immunoassay technology that allow detection of proteins and nucleic acids at lowest possible levels (Photo courtesy of Quanterix)
Blood-based tests for brain amyloid-β (Aβ) pathology are needed for widespread implementation of Alzheimer disease (AD) biomarkers in clinical care and to facilitate patient screening and monitoring of treatment responses in clinical trials.
Reliable measurements of Aβ in blood proved challenging until the development of advanced mass spectrometry and immunodetection methods. Recent articles have suggested that Aβ42/40 quantified using ultrasensitive and fully automated immunoassay platforms could predict Aβ-PET status (especially when combined with APOE genotype) with accuracy approaching that of MS-based Aβ42/40 measures.
An international team led by Clinical Neuroscientists at Lund University (Lund, Sweden) compared the performance of plasma Aβ42/40 measured using eight different Aβ assays when detecting abnormal brain Aβ status in patients with early AD. The study included 182 cognitively unimpaired participants and 104 patients with mild cognitive impairment who were enrolled at three different hospitals in Sweden and underwent Aβ positron emission tomography (PET) imaging and cerebrospinal fluid (CSF) and plasma collection from 2010 to 2014.
Plasma Aβ42/40 was measured using an immunoprecipitation-coupled mass spectrometry developed at Washington University School of Medicine (IP-MS-WashU, St Louis, MO, USA), antibody-free liquid chromatography MS developed by Araclon (LC-MS-Arc, Zaragoza, Spain), and diverse immunoassays. Plasma Aβ42/40 was also measured using an IP-MS–based method from Shimadzu (Kyoto, Japan) in 200 participants (IP-MS-Shim) and an IP-MS–based method from the University of Gothenburg (IP-MS-UGOT, Gothenburg, Sweden) and another immunoassay, the N4PE Simoa immunoassay (IA-Quan, Quanterix Billerica, MA, USA) among 227 participants.
When the team identified participants with abnormal CSF Aβ42/40 in the whole cohort, plasma IP-MS-WashU Aβ42/40 showed significantly higher accuracy than LC-MS-Arc Aβ42/40, and some immunoassays. Plasma IP-MS-WashU Aβ42/40 performed significantly better than IP-MS-UGOT Aβ42/40 and IA-Quan Aβ42/40, while there was no difference in the AUCs between IP-MS-WashU Aβ42/40 and IP-MS-Shim Aβ42/40) in the two sub-cohorts where these biomarkers were available. Plasma IPMS-WashU Aβ42/40 and IP-MS-Shim Aβ42/40 showed highest coefficients for correlations with CSF Aβ42/40.
The authors concluded that the results from two independent cohorts indicate that certain MS-based methods performed better than most of the immunoassays for plasma Aβ42/40 when detecting brain Aβ pathology. The study was published on September 20, 2021 in the journal JAMA Neurology.
Related Links:
Lund University
Washington University School of Medicine
Araclon
University of Gothenburg
Quanterix
Reliable measurements of Aβ in blood proved challenging until the development of advanced mass spectrometry and immunodetection methods. Recent articles have suggested that Aβ42/40 quantified using ultrasensitive and fully automated immunoassay platforms could predict Aβ-PET status (especially when combined with APOE genotype) with accuracy approaching that of MS-based Aβ42/40 measures.
An international team led by Clinical Neuroscientists at Lund University (Lund, Sweden) compared the performance of plasma Aβ42/40 measured using eight different Aβ assays when detecting abnormal brain Aβ status in patients with early AD. The study included 182 cognitively unimpaired participants and 104 patients with mild cognitive impairment who were enrolled at three different hospitals in Sweden and underwent Aβ positron emission tomography (PET) imaging and cerebrospinal fluid (CSF) and plasma collection from 2010 to 2014.
Plasma Aβ42/40 was measured using an immunoprecipitation-coupled mass spectrometry developed at Washington University School of Medicine (IP-MS-WashU, St Louis, MO, USA), antibody-free liquid chromatography MS developed by Araclon (LC-MS-Arc, Zaragoza, Spain), and diverse immunoassays. Plasma Aβ42/40 was also measured using an IP-MS–based method from Shimadzu (Kyoto, Japan) in 200 participants (IP-MS-Shim) and an IP-MS–based method from the University of Gothenburg (IP-MS-UGOT, Gothenburg, Sweden) and another immunoassay, the N4PE Simoa immunoassay (IA-Quan, Quanterix Billerica, MA, USA) among 227 participants.
When the team identified participants with abnormal CSF Aβ42/40 in the whole cohort, plasma IP-MS-WashU Aβ42/40 showed significantly higher accuracy than LC-MS-Arc Aβ42/40, and some immunoassays. Plasma IP-MS-WashU Aβ42/40 performed significantly better than IP-MS-UGOT Aβ42/40 and IA-Quan Aβ42/40, while there was no difference in the AUCs between IP-MS-WashU Aβ42/40 and IP-MS-Shim Aβ42/40) in the two sub-cohorts where these biomarkers were available. Plasma IPMS-WashU Aβ42/40 and IP-MS-Shim Aβ42/40 showed highest coefficients for correlations with CSF Aβ42/40.
The authors concluded that the results from two independent cohorts indicate that certain MS-based methods performed better than most of the immunoassays for plasma Aβ42/40 when detecting brain Aβ pathology. The study was published on September 20, 2021 in the journal JAMA Neurology.
Related Links:
Lund University
Washington University School of Medicine
Araclon
University of Gothenburg
Quanterix
Latest Clinical Chem. News
- AI-Based Blood Test Diagnose Multiple Brain Disorders from Blood Sample
- Automated NfL Assay Supports Monitoring of Neurological Disorders
- Blood-Based Screening Test Targets Early Detection of Colorectal Cancer
- New CLIA Status Brings Mass Spectrometry Steroid Testing to Routine Labs
- CSF Biomarker Improves Diagnosis of Parkinson’s Disease and Lewy Body Dementia
- Simple Urine Home Test Kit Could Detect Early-Stage Breast Cancer
- Study Shows Dual Biomarkers Improve Accuracy of Alzheimer’s Detection
- New Tool Tracks Biomarker Changes to Predict Myeloma Progression
- New Plasma Tau Assay Improves Prediction of Alzheimer’s Progression
- First IVD Immunoassay to Detect Alzheimer’s Risk Gene Variant Receives CE Mark
- Routine Blood Markers Predict Heart Failure Risk in Prediabetes
- AI Model Enables Personalized Glucose Predictions for Type 1 Diabetes
- AI-Powered Blood Test Distinguishes Deadly Cardiac Events
- AI Sensor Detects Neurological Disorders Using Single Saliva Drop
- Blood Test Tracks Transplant Health Using Donor DNA
- New Blood Test Index Offers Earlier Detection of Liver Scarring
Channels
Molecular Diagnostics
view channel
RNA Profiling Uncovers Therapeutic Targets in Solid Tumors
Many patients with advanced solid tumors exhaust broad DNA panel testing yet still lack biomarkers that match guideline-recommended therapies, limiting access to targeted options. Expanding molecular profiling... Read more
Whole Genome Sequencing in Routine Care Expands Rare Disease Detection
Rare diseases often involve prolonged diagnostic journeys that delay clinical decision-making and complicate family planning. As phenotypes become more heterogeneous, sequencing-based methods are increasingly... Read moreHematology
view channel
Rapid Cartridge-Based Test Aims to Expand Access to Hemoglobin Disorder Diagnosis
Sickle cell disease and beta thalassemia are hemoglobin disorders that often require referral to specialized laboratories for definitive diagnosis, delaying results for patients and clinicians.... Read more
New Guidelines Aim to Improve AL Amyloidosis Diagnosis
Light chain (AL) amyloidosis is a rare, life-threatening bone marrow disorder in which abnormal amyloid proteins accumulate in organs. Approximately 3,260 people in the United States are diagnosed... Read moreImmunology
view channel
Antibody Blood Test Identifies Active TB and Distinguishes Latent Infection
Active tuberculosis (TB) remains a leading cause of death and illness worldwide, yet distinguishing contagious disease from latent infection continues to challenge clinicians. Standard screening tools... Read more
FDA Approval Expands Use of PD-L1 Companion Diagnostic in Esophageal and GEJ Carcinomas
Esophageal and gastroesophageal junction carcinomas (GEJ) have a poor prognosis, with approximately 16,250 deaths in the United States in 2025 and a five-year relative survival of 21.9%.... Read more
Study Identifies Inflammatory Pathway Driving Immunotherapy Resistance in Bladder Cancer
Bladder cancer remains a prevalent malignancy with variable responses to immune checkpoint inhibitors. Clinicians often observe elevated C-reactive protein and interleukin-6 in affected patients, yet the... Read moreMicrobiology
view channel
New Bacterial Target Identified for Early Detection of Noma
Noma is a rapidly progressing orofacial infection that begins as gingivitis and can destroy oral and facial tissues, primarily affecting young children living in extreme poverty. Without treatment, it... Read more
Genomic Analysis Links Emerging Streptococcal Strains to Specific Infections
Streptococcus dysgalactiae subspecies equisimilis (SDSE) infections are increasing worldwide and include variants that may lead to severe disease. Researchers now report that whole-genome sequencing of... Read morePathology
view channel
AI Tool Predicts Patient-Specific Chemotherapy Benefit in Breast Cancer
Selecting adjuvant chemotherapy for early-stage breast cancer is typically guided by recurrence risk and population-level averages rather than patient-specific benefit. However, existing clinicopathologic... Read more
AI-Based Pathology Model Guides Chemotherapy Decisions in Breast Cancer
Selecting adjuvant chemotherapy for early-stage breast cancer remains a difficult decision because only a subset benefits and many undergo toxicity without gain. Genomic assays can help but are costly,... Read moreTechnology
view channel
New AI Tool Enables Rapid Treatment Selection in Pediatric Leukemia
Children with T-cell acute lymphoblastic leukemia face an aggressive disease that remains difficult to treat. Although remission rates have improved, many survivors experience long-term effects from intensive... Read more
Breakthrough Mass Spectrometry Design Could Enable Ultra-Low Abundance Detection
Mass spectrometry is central to identifying and quantifying molecules in complex biological samples, but conventional instruments typically analyze ions sequentially, which can limit detection of rare species.... Read moreIndustry
view channel
Takara Bio USA and Hamilton Partner Partner to Automate NGS Library Preparation
Takara Bio USA, Inc. (San Jose, CA, USA), a wholly owned subsidiary of Takara Bio Inc., and Hamilton Company (Reno, NV, USA) announced a development and co-marketing agreement to deliver integrated, automated... Read more







