Ultra-sensitive Targeted Exosomal Proteomic Detection Service

The main technologies currently available for exosomal proteomic studies are biomass spectrometry, antibody/antigen microarrays, aptamer assays, reverse phase protein arrays, and PEA (proximity extension assay). Of these, PEA technology is widely used due to its hypersensitivity and stability. Creative Biolabs offers an ultra-sensitive targeted exosomal proteomic detection service using PEA technology, which integrates the advantages of the high specificity of immunoassay and high throughput of nucleic acid detection, allowing the recognition of thousands of proteins with only tiny amounts of exosomal protein samples.

Ultra-sensitive Targeted Exosomal Proteomic Detection based on PEA

Currently, commonly known proteomics methods, including bidirectional gel electrophoresis, protein/antibody microarrays, and biomass spectrometry, are available. All of the above methods are limited by key factors such as detection speed, throughput, multiplex detection capability, and sensitivity, which prevent them from obtaining sufficient and effective information on complex and large proteomes. Among the traditional exosome proteomics techniques, biomass spectrometry is the most commonly used approach for the identification and quantification of unknown and known proteins. However, for low-abundance exosomal proteins, mass spectrometry still has limitations. In addition, protein profiling takes a long time and data analysis is highly dependent on expertise. All of the above, have become the rate-limiting factors for the development of exosome proteomics.

PEA technology is a high throughput, high specificity, high sensitivity, and high dynamic range targeted proteomic quantitative assay platform that combines the high specificity of antibody immunoassays with the high sensitivity/high throughput of genomics. PEA contains a pair of specific antibodies that recognize the target protein, which is coupled with a specific DNA single strand. When this pair of antibodies binds to the target protein, the two DNA single strands in the neighboring position can complementarily bind and be extended by linkage to form a double-stranded DNA template, subtly converting protein quantification into DNA quantification, then finally using microfluidic qPCR or NGS sequencing for quantitative detection.

Fig.1 PEA technology in combination with NGS readout to measure nearly 1500 validated proteins in parallel. (Wik, 2021)

Benefits of Ultra-sensitive Targeted Exosomal Proteomic Detection

Ultra-sensitive targeted exosomal proteomic detection, developed based on PEA technology, and combined with the powerful features of microfluidic microarray and qPCR technology, enables rapid, high-throughput, high-specificity, and high-sensitivity targeted proteomic quantitative analysis. These features fit perfectly with the demand for exosome micro-detection and broaden the application scenario of exosome proteomics. Traditional biomass spectrometry techniques have high protein starting amounts, are susceptible to high protein abundance, and are not as effective in detecting low-abundance proteins. For example, conventional mass spectrometry is less effective in detecting cytokines that are critical in immune or inflammatory studies due to their low expression. In contrast, this ultra-sensitive protein microarray has a dedicated inflammation panel, enabling high-throughput detection of inflammatory factors. This improves the efficiency and cost-effectiveness of cytokine research and provides a solution to study the relationship between exosomes and inflammation and immunity. In addition to inflammation, there are also treasures in other panels, for example, the one for Immuno Oncology contains PD-L1, CD27, and Gal-9, which are the low-abundance star molecules of exosomes. All these advantages support exosomal protein-based marker studies and mediated mechanistic studies.

Fig.2 Procedure for plasma EV (plEV) isolation and analysis by multiplex immunoassay based on proximity extension technology. (Indira, 2019)

PEA assays have a high throughput of genomics while retaining the specificity of protein/antibody recognition while overcoming the limitations of low abundance detection of exosomal proteins. Creative Biolabs utilizes PEA technology to accurately detect thousands of proteins with only 1-10 ul of protein solution and 100% coverage of major signaling pathways, truly assisting in the service of ultra-sensitive targeted exosomal protein detection. This facilitates clients to advance research on early screening, diagnosis and prognosis of exosome-based diseases as well as physiopathological mechanisms. Please contact us to learn more.

References

Wik, L.; et al. Proximity extension assay in combination with next-generation sequencing for high-throughput proteome-wide analysis. Mol Cell Proteomics. 2021, 20: 100168.
Indira, Chandran, V.; et al. Ultrasensitive immunoprofiling of plasma extracellular vesicles identifies syndecan-1 as a potential tool for minimally invasive diagnosis of glioma. Clin Cancer Res. 2019, 25(10): 3115-3127.

Plant Exosome Isolation