Amyloid-beta Aggregates Determination Assay

Alzheimer's disease (AD) is a neurodegenerative disease that is widely existed in the elderly, accompanied by symptoms such as memory loss, decreased cognitive ability, and emotional changes. The error folding and extracellular agglomeration of amyloid-β (Aβ) peptides cause the deposition of Aβ-like protein plaques in the brain, which are one of the important hallmarks of AD. In order to explore the aggregation process of Aβ, plenty of technologies have been applied in the past few years. Creative Biolabs has successfully developed an advanced Aβ aggregation assay platform and diverse cell models to meet your specific needs.

Isoforms of Aβ

Aβ peptide is considered to be a promising biomarker for the early diagnosis and progress of AD. The isoforms of Aβ in human cerebrospinal fluid include Aβ1–28, Aβ1-33, Aβ1-34, Aβ1-37, Aβ1-38, Aβ1-39, Aβ1-40 and Aβ1-42. The most important subtypes are Aβ1-40 and Aβ1-42 because they exist in more than 90% of plaques. Aβ1-40 is the most abundant while Aβ1-42 is easier to aggregate. A large number of genetic evidence indicates that the aggregation of Aβ1-40 and Aβ1-42 is the main reason for the progress of AD. Therefore, inhibiting Aβ self-assembly is an attractive strategy for the treatment of AD.

Introduction to Aβ Aggregation

Since Aβ peptides play an important role in senile plaque formation, exploring the structure and biochemical properties of Aβ will provide a better understanding of AD at the molecular level. Aβ monomers assemble into different forms of soluble oligomers, which then form regular fibrils. The aggregation process of Aβ is related to several factors, such as concentration, pH, and temperature. It has been reported that Aβ aggregates can produce neurotoxicity through different pathways. In addition, Aβ aggregates can be assembled from different allotypes, such as Aβ1-40 and Aβ1-42, which vary in length and concentration, and may have different toxicities.

Fig.1 Schematic representation of Aβ aggregation. (Huang & Liu, 2020)

Methods for Aβ Aggregate Determination at Creative Biolabs

The aggregation tendency of Aβ is an important factor in AD pathophysiology. Therefore, techniques to characterize, quantify and visualize different Aβ species are highly desirable.

• Traditional methods

At Creative Biolabs, enzyme-linked immunosorbent assay (ELISA) and mass spectrometry (MS) are the most commonly used methods to detect Aβ monomers and aggregates.

• Biosensor approaches

Creative Biolabs provides new biosensor approaches with low cost and high sensitivity such as surface plasmon resonance, localized surface plasmon resonance, electrochemistry, resonant light scattering, and speckle immunoassays.

• Electrochemical methods

At Creative Biolabs, electrochemical methods such as cyclic voltammetry (CV), differential pulse (DP), and square wave (SW) have gradually emerged as complementary tools for studying Aβ peptide aggregation and elucidating AD mechanisms.

Different techniques have their advantages and disadvantages, and using a combination of different techniques to study Aβ aggregation will reveal optimal information. With diverse cell models and rich experience, Creative Biolabs focuses on providing the most suitable testing services for global customers, please contact us for a detailed quotation.

Reference

1. Huang, Y. R.; Liu, R. T. The toxicity and polymorphism of β-amyloid oligomers. International Journal of Molecular Sciences. 2020, 21(12): 4477.