title: Isolation of rare tumor cells from blood cells with buoyant immuno-microbubbles.
abstract: Circulating tumor cells (CTCs) are exfoliated at various stages of cancer, and could provide invaluable information for the diagnosis and prognosis of cancers. There is an urgent need for the development of cost-efficient and scalable technologies for rare CTC enrichment from blood. Here we report a novel method for isolation of rare tumor cells from excess of blood cells using gas-filled buoyant immuno-microbubbles (MBs). MBs were prepared by emulsification of perfluorocarbon gas in phospholipids and decorated with anti-epithelial cell adhesion molecule (EpCAM) antibody. EpCAM-targeted MBs efficiently (85%) and rapidly (within 15 minutes) bound to various epithelial tumor cells suspended in cell medium. EpCAM-targeted MBs efficiently (88%) isolated frequent tumor cells that were spiked at 100,000 cells/ml into plasma-depleted blood. Anti-EpCAM MBs efficiently (>77%) isolated rare mouse breast 4T1, human prostate PC-3 and pancreatic cancer BxPC-3 cells spiked into 1, 3 and 7 ml (respectively) of plasma-depleted blood. Using EpCAM targeted MBs CTCs from metastatic cancer patients were isolated, suggesting that this technique could be developed into a valuable clinical tool for isolation, enumeration and analysis of rare cells.
authors.affiliation: Moores Cancer Center, University of California San Diego, La Jolla, California, USA.
authors.forename: Guixin
authors.initials: G
authors.lastname: Shi
authors.forename: Wenjin
authors.initials: W
authors.lastname: Cui
authors.forename: Michael
authors.initials: M
authors.lastname: Benchimol
authors.forename: Yu-Tsueng
authors.initials: YT
authors.lastname: Liu
authors.forename: Robert F
authors.initials: RF
authors.lastname: Mattrey
authors.forename: Rajesh
authors.initials: R
authors.lastname: Mukthavaram
authors.forename: Santosh
authors.initials: S
authors.lastname: Kesari
authors.forename: Sadik C
authors.initials: SC
authors.lastname: Esener
authors.forename: Dmitri
authors.initials: D
authors.lastname: Simberg
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D000951:Antigens, Neoplasm / Q000276:immunology / Q000378:metabolism; D001773:Blood Cells / Q000276:immunology / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000378:metabolism; D045744:Cell Line, Tumor; D000071858:Epithelial Cell Adhesion Molecule; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods*; D045423:Microbubbles; D008962:Models, Theoretical; D009360:Neoplastic Cells, Circulating / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D015815:Cell Adhesion Molecules; D000071858:Epithelial Cell Adhesion Molecule