Isolating EGFR Overexpressing Carcinoma Cells from Human Whole Blood by Bio-Ferrography

Background: The epidermal growth factor receptor (EGFR) is overexpressed in carcinoma. In some cases, including in colorectal cancer, it is used as a therapeutic target. Bio-Ferrography is a non-destructive method for isolating magnetized cells and tissues from a fluid onto a glass slide based on their interaction with an external, strong and focused magnetic field. Methods: Here, we implement Bio-Ferrography to separate EGFR positive cancer cells from EGFR negative non-cancer cells, mixed at a ratio of 1 to 1 × 10⁶ , from either PBS or human whole blood (HWB). Incubation of the cells with an anti-EGFR antibody and magnetic microbeads coupled to a secondary antibody was used to magnetize the target cells prior to the ferrographic analysis. Results: A procedure was developed for "a proof of concept" isolation. Recovery values as high as 78% for 1 mL PBS, and 53% for 1 mL HWB, with a limit of detection (LOD) of 30 and 100 target cells, respectively, were achieved. Conclusions: These capture efficiency values are considered significant and therefore warrant further study on isolation of real circulating tumor cells (CTCs) from blood samples of patients, aiming at early diagnosis of EGFR overexpressing tumor types. This article is protected by copyright. All rights reserved.