The amyloid cascade hypothesis theorizes that the excessive accumulation of Amyloid beta (A-beta) peptides in the brain are the initiating factor for the development of Alzheimer’s disease (AD). Specifically, that aggregates of A-beta peptides, which are formed following cleavage of the Amyloid Precursor Protein (APP), instigate a series of events that leads to neurodegeneration and, eventually, AD. This hypothesis arose from the observation that the plaques identified in brains afflicted with AD were composed largely of A-beta peptides, and was further supported by the finding that many AD risk and deterministic genes coded for proteins involved in the production or clearance of A-beta peptides.
A-beta (aa1-40) is the most abundant A-beta isoform in the brain; however, A-beta (aa1-42) is the isoform most associated with development as AD as it is more prone to aggregation. Continuing AD research, though, has shown that the connection between A-beta accumulation, plaque formation, and cognitive alterations is much more complex. In addition to amyloid plaques, soluble, multimeric forms of A-beta peptides may also induce synaptotoxicity and neurotoxicity. So, as scientists are attempting to unravel the role of A-beta peptides in AD, high-performing research tools are needed to detect and measure specific A-beta peptide levels in neural tissue samples.
Many commercially available ELISAs designed to measure A-beta (aa1-40) and (aa1-42) have several limitations, including cross-reactivity with additional A-beta peptides, interference from sample buffer and/or matrix factors, and general lot-to-lot inconsistencies. R&D Systems® Human Amyloid beta (aa1-40) and (aa1-42) Quantikine® ELISA Kits have been designed to overcome the challenges of measuring A-beta (aa1-40) and (aa1-42) in tissue lysates, cerebrospinal fluid, and cell culture supernates.
The Top 5 Features of R&D Systems® Human Amyloid beta (aa1-40) and (aa1-42) Quantikine® ELISA Kits are:
#5 Our ELISAs Use Recombinant Monoclonal Antibodies
Recombinant monoclonal antibodies are increasingly being used for protein detection as they offer several advantages over conventionally produced monoclonal antibodies, including improved sensitivity, specificity, and generating highly reproducible results. Our A-beta Quantikine® ELISA Kits were developed using recombinant monoclonal antibodies to ensure reproducibility over time.
#4 Our ELISAs Use an Optimally Formulated Assay Diluent
A current problem for using ELISA to quantify a protein in brain tissue is that the most common extraction buffer used for brain lysates, RIPA, impairs the ability of the antibody to bind to its antigen, reducing the signal strength. Our A-beta Quantikine® ELISA Kits use an optimally formulated assay diluent that minimizes the interference produced by RIPA buffer.
#3 Our Amyloid beta (aa1-42) ELISA Uses a Non-Aggregating Standard
It has been repeatedly shown that the A-beta (aa1-42) peptide can spontaneously aggregate into multimeric assemblies. Therefore, special care must be taken when choosing the correct A-beta (aa1-42) peptide standard so that it won’t aggregate and cause a loss of signal when generating the standard curve. Our Human Amyloid beta (aa1-42) Quantikine® ELISA Kit uses a non-aggregating mimetic human A-beta (aa1-42) peptide as a standard, and every lot is tested to make sure that all assay kits produce a consistent and linear standard curve.
#2 Our ELISAs are Validated for Use in Complex, Neural Tissue Samples
Complex sample matrices contain a variety of factors that can cause immunoassay interference. Thus, using an ELISA that has not been validated for the relevant sample types may not give accurate results. Our A-beta Quantikine® ELISAs are validated for use in cerebrospinal fluid and tissue lysates, and can detect A-beta peptides in the pg/mL range. The validation testing for all our Quantikine® ELISA Kits includes intra- and inter-assay precision, assay linearity and recovery, and kit stability and assay drift. Additionally, the detection of natural analyte in validated sample types are compared to published analyte concentrations.
#1 Our ELISAs are Developed with R&D Systems® Quality
Only R&D Systems has the highest-quality ELISAs available. We have almost 30 years of experience designing, testing, and optimizing immunoassay kits to ensure the highest level of performance in analyte quantification and consistency from one lot to the next. This is why researchers trust our ELISAs and they are referenced more than any other ELISA on the market.
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