Exosomes are involved in a variety of physiological and pathological processes, and they also have great potential in the field of liquid biopsy. Except for exosomes derived from single cell culture medium, exosomes in body fluids and tissues are mixed sets and have very large heterogeneity. However, traditional exosome sequencing analyzes all exosome subsets and obtains the average result of all exosomes. This ignores or conceals individual differences in exosomes, and cannot fully capture the complexity, diversity, and differences in functions of exosomes. Single-cell proteome sequencing (scP-seq) can quantify all proteins expressed in a single cell, compare the types and contents of proteins between different single cells, and help to clarify the functional differences between cells. Most importantly, proteins are direct performers of biological functions within cells. Therefore, compared with single-cell transcriptome sequencing, scP-seq can reveal changes in protein expression in a single cell, revealing the nature of cellular regulation more directly. Therefore, the innovative combined analysis of scP-seq data and exosome proteome data will help provide evidence for the traceability of exosomes from the protein level. Creative Biolabs can provide single-cell and exosome combined proteomics research service, helping customers to more accurately analyze the regulatory nature of exosomes from the protein level.

Research Result of Exosome Analysis by Single Exosome Surface Proteomics

As an important communication medium, exosomes are involved in many biological internal processes. Obtaining the protein profile characteristics of single exosomes is of great help to the study of exosome heterogeneity, cell-to-cell regulatory mechanism, and disease biomarkers. Based on the multiplex immunoassay technique, a research team for the first time performed a simultaneous analysis of all exosomes in a mixed set by proximity coding (PBA) and found low-abundance exosome subpopulations in samples. The research team claims that the detection resolution of PBA can be as accurate as a single exosome surface molecular protein, which can identify low-abundance exosome surface proteins with higher disease diagnostic value. We believe that single exosome surface proteomics will be widely used in the study of exosome heterogeneity in the future.

Fig. 1 Design and workflow of proximity barcoding assay. (Wu, 2019)

Single-Cell Proteomics and Exosome Proteomics Combined Research Service

Creative Biolabs innovatively extends protein analysis capabilities directly to the single-cell level. We can apply a microfluidic system that can simultaneously isolate 500-1500 single cells and combine it with antibody barcode array technology for scP-seq. scP-seq of tissue can analyze the tissue microenvironment from the two dimensions of cell subgroups and intercellular space exosomes, which can provide a basis for revealing the exosome communication network between cell subgroups in the tissue microenvironment. In addition, the combined scP-seq analysis of body fluid-derived exosomes and tissues can help to more accurately find key role proteins and disease marker proteins in exosomes.

Fig. 2 Single-cell proteomics with SCoPE2. (Petelski, 2021)

Creative Biolabs has a leading technology platform and an experienced scientific research team, which can provide customers with innovative single-cell and exosome combined proteomics research service to facilitate the study of exosome heterogeneity at the protein expression level. In addition, we can also provide one-stop services from exosome extraction, exosome identification, and exosome proteomics to in vivo and in vitro exosome functional research, and help you mine key proteins in exosomes. If you want to determine the traceability of these exosomes carrying key proteins, please contact us.

References

1. Wu, D.; Yan, J.; et al. Profiling surface proteins on individual exosomes using a proximity barcoding assay. Nature Communications. 2019. 10(1):3854.
2. Petelski, AA.; Emmott, E.; et al. Multiplexed single-cell proteomics using SCoPE2. Nature Protocols. 2021. 16(12):5398-5425.

• Single-Cell & Exosome Combined Transcriptomics Research