There is a growing demand for biomarkers that can help detect diseases like cancer or neurodegenerative diseases at an early stage, as well as for follow-up treatments. Exosomes, a subclass of membrane coated vesicles released from the cell through exocytosis, could be the next big step in the hunt.
Exosomes are important in a number of biological processes such as intracellular signaling, coagulation and protein transportation. They carry surface proteins from their tissue of origin which make them very suitable as biomarkers. The problem, however, is that they need to be be studied individually in order to determine each exosome’s tissue of origin, something that has been very difficult so far.
In a recent study, published in Nature Communications and led by Masood Kamali-Moghaddam (SciLifeLab/Uppsala University) and Ulf Landegren (SciLifeLab/Uppsala University), researchers found an efficient way to identify surface proteins on individual exosomes in large samples. Proximity barcoding assay (PBA) is a technology that can identify tens of thousands of exosomes in a sample by combining DNA-conjugated antibodies with DNA sequencing. By tagging individual exosomes with small unique DNA-clusters, the researchers could identify the surface proteins. The new technique might also play an important role when identifying other exosomes capable of working as biomarkers in a variety of diseases.
“We will make PBA technology available to other researchers later this year and we believe that this analysis of individual exosomes will enable this new and exciting group of biomarkers to reach their full potential’ says Di Wu, first author of the paper, inventor of the PBA technology and founder of Vesicode AB in a press release from Uppsala University.
“The PBA technology will enable large-scale screening for biomarkers in various diseases, thereby complementing the methods we have previously developed for sensitive and specific diagnostics using exosomes, says Masood Kamali-Moghaddam (SciLifeLab/Uppsala University) in the press release.
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