LabMedica

Download Mobile App
Recent News Expo Clinical Chem. Molecular Diagnostics Hematology Immunology Microbiology Pathology Technology Industry Focus

Blood Test Detects Chronic Traumatic Encephalopathy During Life

By LabMedica International staff writers
Posted on 22 Mar 2016
Image: The NanoSight LM10 instrument provides an easy-to-use, reproducible platform for nanoparticle characterization (Photo courtesy of Malvern Instruments).
Image: The NanoSight LM10 instrument provides an easy-to-use, reproducible platform for nanoparticle characterization (Photo courtesy of Malvern Instruments).
Chronic traumatic encephalopathy (CTE) is a tauopathy associated with prior exposure to repetitive head impacts, such as those incurred through American football and other collision sports and diagnosis is made through neuropathological examination.

A method has been developed for measuring plasma exosomal tau. Exosomes are very small vesicles that are released from all types of cells throughout the body, including brain cells. They can be isolated in all body fluids, including plasma, a component of blood.

Scientists at Boston University School of Medicine (MA, USA) and their colleagues examined 78 former National Football League (NFL) players and a control group of 17 former non-contact sport athletes. Extracellular vesicles were isolated from plasma. Fluorescent nanoparticle tracking analysis was used to determine the number of vesicles staining positive for tau. Blood was drawn by venipuncture and immediately processed. Plasma samples were stored in 0.75 mL tubes at -80 °C, packed in dry ice, and shipped overnight in one batch to the Exosome Sciences laboratory (Monmouth Junction, NJ, USA).

Extracellular vesicles were isolated from the plasma samples by size exclusion chromatography. Plasma samples were applied to the column and it was then run isocratically. The elution was monitored at 280 nm and the void volume material (exosome fraction) was collected and pooled. The size profiles and concentrations of the chromatographically isolated exosomes were performed using the Nanosight LM10 instrument (Malvern Instruments Ltd.; Malvern, UK) equipped with a 405 nm laser, a scientific complementary metal-oxide-semiconductor (sCMOS) camera and Nanoparticle Tracking Analysis (NTA) software.

The method of measuring plasma exosomal tau is referred to as a TauSome. The groups did not differ in total plasma exosomes, but the NFL group had significantly higher plasma exosomal tau than the control group. The C-statistic is maximized when the plasma exosomal tau level is set to 0. Using 0 as a threshold resulted in 82% sensitivity, 100% specificity, 100% positive predictive value and 53% negative predictive value. The number of tau-positive plasma exosomes was significantly correlated with performance on standardized tests of memory and psychomotor speed; the higher the TauSome level, the worse the performance.

Jim Joyce, Founder of Exosome Sciences and Chairman and CEO of Aethlon Medical (San Diego, CA, USA), said, “We are extremely pleased that our initial study data has been published and we appreciate forthcoming opportunities to further advance our TauSome biomarker as a noninvasive solution to detect and monitor CTE in living individuals.” The study was published on February 10, 2016, in the Journal of Alzheimer's Disease.

Related Links:

Boston University School of Medicine
Exosome Sciences
Malvern Instruments Ltd.


Platinum Member
Automated Coagulation Analyzer
Hemolumi H6
Gold Member
Flocked Fiber Swabs
Puritan® Patented HydraFlock®
Pipette Calibration System
Artel PCS®
Electrolyte Analyzer
BKE-B

Channels

Clinical Chemistry

view channel
Image: New findings demonstrate that anti-Müllerian hormone (AMH) may help identify which breast cancer patients are most likely to benefit from chemotherapy plus endocrine therapy (Image Credit: Shutterstock)

AMH Test Helps Predict Adjuvant Chemotherapy Benefit in Premenopausal Breast Cancer

Hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) breast cancer can present a difficult treatment decision in premenopausal patients with low recurrence scores.... Read more

Molecular Diagnostics

view channel
Image Credit: iStock

Sequencing-Based Newborn Screening Identifies Pediatric Cancer Risk at Birth

Newborn screening in the United States relies on heel-stick blood spots to identify rare, treatable disorders through biochemical testing, but these programs generally do not assess inherited cancer risk... Read more

Microbiology

view channel
Image: The QIAstat-Dx BCID GPF Plus AMR Panel is the first QIAstat-Dx panel for bloodstream infections to receive FDA clearance (Photo courtesy of Qiagen)

FDA Clears One-Hour Panel for Bloodstream Infection and AMR Detection

Bloodstream infections can rapidly progress to sepsis, a life-threatening condition affecting an estimated 1.7 million adults in the U.S. each year. Rapid identification of pathogens and antimicrobial... Read more