title: Isolating epidermal growth factor receptor overexpressing carcinoma cells from human whole blood by bio-ferrography.
abstract: 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 nondestructive 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 noncancer cells, mixed at a ratio of 1 to 1 × 10(6) , from either phosphate-buffered saline or human whole blood. 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 phosphate-buffered saline, and 53% for 1 mL human whole blood, with a limit-of-detection 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 from blood samples of patients, aiming at early diagnosis of EGFR-overexpressing tumor types.
authors.affiliation: Biomaterials and Corrosion Lab, Department of Materials Science and Engineering, Tel-Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel.
authors.forename: Ofer
authors.initials: O
authors.lastname: Levi
authors.forename: Assaf
authors.initials: A
authors.lastname: Shapira
authors.forename: Baruch
authors.initials: B
authors.lastname: Tal
authors.forename: Itai
authors.initials: I
authors.lastname: Benhar
authors.forename: Noam
authors.initials: N
authors.lastname: Eliaz
mesh_terms: D000818:Animals; D066246:ErbB Receptors / Q000032:analysis* / Q000096:biosynthesis*; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D060328:Magnetic Phenomena; D059346:Magnets / Q000032:analysis*; D051379:Mice; D041681:NIH 3T3 Cells; D009360:Neoplastic Cells, Circulating / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D066246:ErbB Receptors
keywords: A431 cells; Bio-Ferrography; EGFR; human whole blood; immunomagnetic separation; monoclonal antibody