Autoantibody panel on small extracellular vesicles for the early detection of lung cancer

This study evaluated a different form of autoantibody, which is on small extracellular vesicles (sEVs), as a biomarker for early detection of lung cancer. The sEVs were isolated from plasma by ultracentrifugation and validated with morphology and typical markers. The autoantibody levels were quantified by enzyme-linked immunosorbent assay, and further analysis indicated that the autoantibody panel on sEVs was better than that from serum to distinguish benign lung disease (n = 32) from lung cancer (n = 90). In the prospective study, autoantibody on sEVs performed better in identification of patients with a higher risk of lung cancer. Further-more, with immunogold labeling transmission electron microscopy, Nanoflow cytometry and binding tests, we illustrated that the autoantibodies could bind to the antigens on sEVs, which may explain the detected auto -antibodies on sEVs. Besides, the binding resulted in the attenuation of complement-mediated cytotoxicity, which may contribute to the immune escape of lung cancer.