title: Isolating highly enriched populations of circulating epithelial cells and other rare cells from blood using a magnetic sweeper device.
abstract: The enumeration of rare circulating epithelial cells (CEpCs) in the peripheral blood of metastatic cancer patients has shown promise for improved cancer prognosis. Moving beyond enumeration, molecular analysis of CEpCs may provide candidate surrogate endpoints to diagnose, treat, and monitor malignancy directly from the blood samples. Thorough molecular analysis of CEpCs requires the development of new sample preparation methods that yield easily accessible and purified CEpCs for downstream biochemical assays. Here, we describe a new immunomagnetic cell separator, the MagSweeper, which gently enriches target cells and eliminates cells that are not bound to magnetic particles. The isolated cells are easily accessible and can be extracted individually based on their physical characteristics to deplete any cells nonspecifically bound to beads. We have shown that our device can process 9 mL of blood per hour and captures >50% of CEpCs as measured in spiking experiments. We have shown that the separation process does not perturb the gene expression of rare cells. To determine the efficiency of our platform in isolating CEpCs from patients, we have isolated CEpCs from all 47 tubes of 9-mL blood samples collected from 17 women with metastatic breast cancer. In contrast, we could not find any circulating epithelial cells in samples from 5 healthy donors. The isolated CEpCs are all stored individually for further molecular analysis.
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA.
authors.forename: AmirAli H
authors.initials: AH
authors.lastname: Talasaz
authors.forename: Ashley A
authors.initials: AA
authors.lastname: Powell
authors.forename: David E
authors.initials: DE
authors.lastname: Huber
authors.forename: James G
authors.initials: JG
authors.lastname: Berbee
authors.forename: Kyung-Ho
authors.initials: KH
authors.lastname: Roh
authors.forename: Wong
authors.initials: W
authors.lastname: Yu
authors.forename: Wenzhong
authors.initials: W
authors.lastname: Xiao
authors.forename: Mark M
authors.initials: MM
authors.lastname: Davis
authors.forename: R Fabian
authors.initials: RF
authors.lastname: Pease
authors.forename: Michael N
authors.initials: MN
authors.lastname: Mindrinos
authors.forename: Stefanie S
authors.initials: SS
authors.lastname: Jeffrey
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Davis
mesh_terms: D001773:Blood Cells / Q000166:cytology*; D001943:Breast Neoplasms / Q000473:pathology; D045744:Cell Line, Tumor; D002469:Cell Separation / Q000295:instrumentation*; D003198:Computer Simulation; D004847:Epithelial Cells / Q000166:cytology*; D005260:Female; D005786:Gene Expression Regulation; D015789:HLA-A2 Antigen / Q000276:immunology; D006801:Humans; D008280:Magnetics / Q000295:instrumentation*; D018448:Models, Immunological
chemical_list: D015789:HLA-A2 Antigen