Sorting and identification of circulating tumor cells of gliomas with EGFR antibody-modified immunomagnetic microspheres

This study investigated whether antibody-modified immunomagnetic microspheres (IMs) can be used to detect and quantify circulating tumor cells (CTCs) originating from gliomas in liquid biopsies and whether CTC counts in clinical samples are related to the degree of malignancy of gliomas based on clinical data. Epidermal growth factor receptor (EGFR)-antibody-modified and epithelial cell adhesion molecule (EpCAM)-modified IMs were developed, their physical properties, including particle size and zeta potential as well as their biocompatibility, were characterized, and their ability to detect CTCs originating from gliomas was evaluated using a mouse xenograft model and clinical specimens [cerebrospinal fluid (CSF) and peripheral blood collected from 30 patients with gliomas]. The results showed that EGFR-IMs and EpCAM-IMs had low cytotoxicity and that they could capture CTCs in mouse and human biofluids with high capture efficiency. Moreover, CTC counts in the human CSF were positively correlated with glioma grade. Thus, EGFR-IMs and EpCAM-IMs have clinical applicability for the diagnosis of glioma and for monitoring treatment response in patients.