Bimolecule detection for Extracellular Vesicle Screening

Abstract

Extracellular vesicles (EVs) have been investigated for use in clinical testing in recent years. Specific EV surface proteins provide distinguishing characteristics, but are insufficient for more detailed classification of EVs. Here, we suggest a novel “Bimolecular surface antigen expressed in EV” (BiEV) as a potential indicator for more efficient EV screening. A BiEV can be identified using a proximity labeling method applicable to EV membrane proteins. We examined the screening of BiEV in cancer cell-secreted EV included in serum EVs from a model mouse for lung cancer, showing that the CHL1-SLC4A1 BiEV was a significant candidate. ELISA quantification of CHL1-SLC4A1 BiEV appeared to suggest a potential for cancer screening of these mice. Using the same protocols, we found that CHL1-caspase 14 BiEV was significantly elevated in lung cancer patients. A BiEV strategy may be able to make a contribution to more effective EV screening, resulting in novel clinical applications.