title: Combination of Mechanical and Molecular Filtration for Enhanced Enrichment of Circulating Tumor Cells.
abstract: Circulating tumor cells (CTCs) have been linked to cancer progression but are difficult to isolate, as they are very rare and heterogeneous, covering a range of sizes and expressing different molecular receptors. Filtration has emerged as a simple and powerful method to enrich CTCs but only captures cells above a certain size regardless of molecular characteristics. Here, we introduce antibody-functionalized microfilters to isolate CTCs based on both size and surface receptor expression. We present a 3D printed filtration cartridge with microfabricated polymer filters with 8, 10, 12, 15, or 20 μm-diameter pores. Pristine filters were used to optimize sample dilution, rinsing protocol, flow rate, and pore size, leading to >80% for the recovery of spiked cancer cells with very low white blood cell contamination (<1000). Then, filters were functionalized with antibodies against either epithelial cell adhesion molecule (EpCAM) or epidermal growth factor receptor (EGFR) and the cartridges were used to enrich breast (MDA-MB-231, MCF-7) and renal (786-O, A-498) cancer cells expressing various levels of EpCAM and EGFR. Cancer cells were spiked into human blood, and when using filters with antibodies specific to a molecular receptor expressed on a cell, efficiency was increased to >96%. These results suggest that filtration can be optimized to target specific CTC characteristics such as size and receptor expression and that a diverse range of CTCs may be captured using particular combinations of pore size, filtration parameters, and antibody functionalization.
authors.affiliation: Biomedical Engineering Department, McGill University , 3775 University Street, Montreal, Quebec, Canada H3A 2B4.|McGill University & Genome Quebec Innovation Centre, McGill University , 740 Dr. Penfield Avenue, Montreal, Quebec, Canada H3A 0G1.
authors.forename: Anne
authors.initials: A
authors.lastname: Meunier
authors.affiliation: Biomedical Engineering Department, McGill University , 3775 University Street, Montreal, Quebec, Canada H3A 2B4.|McGill University & Genome Quebec Innovation Centre, McGill University , 740 Dr. Penfield Avenue, Montreal, Quebec, Canada H3A 0G1.|National Research Council of Canada , 75 de Mortagne Boulevard, Boucherville, Quebec, Canada J4B 6Y4.
authors.forename: Javier Alejandro
authors.initials: JA
authors.lastname: Hernández-Castro
authors.affiliation: Biomedical Engineering Department, McGill University , 3775 University Street, Montreal, Quebec, Canada H3A 2B4.|McGill University & Genome Quebec Innovation Centre, McGill University , 740 Dr. Penfield Avenue, Montreal, Quebec, Canada H3A 0G1.
authors.forename: Kate
authors.initials: K
authors.lastname: Turner
authors.affiliation: National Research Council of Canada , 75 de Mortagne Boulevard, Boucherville, Quebec, Canada J4B 6Y4.
authors.forename: Kebin
authors.initials: K
authors.lastname: Li
authors.affiliation: National Research Council of Canada , 75 de Mortagne Boulevard, Boucherville, Quebec, Canada J4B 6Y4.
authors.forename: Teodor
authors.initials: T
authors.lastname: Veres
authors.affiliation: Biomedical Engineering Department, McGill University , 3775 University Street, Montreal, Quebec, Canada H3A 2B4.|McGill University & Genome Quebec Innovation Centre, McGill University , 740 Dr. Penfield Avenue, Montreal, Quebec, Canada H3A 0G1.|Neurology and Neurosurgery Department, McGill University , 3801 University Street, Montreal, Quebec, Canada H3A 2B4.
authors.forename: David
authors.initials: D
authors.lastname: Juncker
mesh_terms: D000906:Antibodies / Q000276:immunology; D002469:Cell Separation / Q000379:methods*; D005374:Filtration / Q000379:methods*; D064368:Healthy Volunteers; D006801:Humans; D008856:Microscopy, Fluorescence; D055616:Microtechnology / Q000295:instrumentation; D009360:Neoplastic Cells, Circulating / Q000276:immunology / Q000473:pathology*; D011108:Polymers / Q000737:chemistry; D014407:Tumor Cells, Cultured
chemical_list: D000906:Antibodies; D011108:Polymers