title: All-in-one centrifugal microfluidic device for size-selective circulating tumor cell isolation with high purity.
abstract: Circulating tumor cells (CTCs) have gained increasing attention owing to their roles in cancer recurrence and progression. Due to the rarity of CTCs in the bloodstream, an enrichment process is essential for effective target cell characterization. However, in a typical pressure-driven microfluidic system, the enrichment process generally requires complicated equipment and long processing times. Furthermore, the commonly used immunoaffinity-based positive selection method is limited, as its recovery rate relies on EpCAM expression of target CTCs, which shows heterogeneity among cell types. Here, we propose a centrifugal-force-based size-selective CTC isolation platform that can isolate and enumerate CTCs from whole blood within 30 s with high purity. The device was validated using the MCF-7 breast cancer cell line spiked in phosphate-buffered saline and whole blood, and an average capture efficiency of 61% was achieved, which is typical for size-based filtration. The capture efficiency for whole blood samples varied from 44% to 84% under various flow conditions and dilution factors. Under the optimized operating conditions, a few hundred white blood cells per 1 mL of whole blood were captured, representing a 20-fold decrease compared to those obtained using a commercialized size-based CTC isolation device. In clinical validation, normalized CTC counts varied from 10 to 60 per 7.5 mL of blood from gastric and lung cancer patients, yielding a detection rate of 50% and 38%, respectively. Overall, our CTC isolation device enables rapid and label-free isolation of CTCs with high purity, which should greatly improve downstream molecular analyses of captured CTCs.
authors.affiliation: Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan, 689-798, Republic of Korea.
authors.forename: Ada
authors.initials: A
authors.lastname: Lee
authors.forename: Juhee
authors.initials: J
authors.lastname: Park
authors.forename: Minji
authors.initials: M
authors.lastname: Lim
authors.forename: Vijaya
authors.initials: V
authors.lastname: Sunkara
authors.forename: Shine Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Gwang Ha
authors.initials: GH
authors.lastname: Kim
authors.forename: Mi-Hyun
authors.initials: MH
authors.lastname: Kim
authors.forename: Yoon-Kyoung
authors.initials: YK
authors.lastname: Cho
mesh_terms: D002469:Cell Separation / Q000379:methods*; D048429:Cell Size; D002498:Centrifugation; D006801:Humans; D061986:MCF-7 Cells; D046210:Microfluidic Analytical Techniques; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D014407:Tumor Cells, Cultured