Institute of Microelectronics, Peking University, 100871, Beijing, China.
Lab Chip. 2018 Dec 18;19(1):68-78. doi: 10.1039/c8lc01048j.
Liquid biopsy techniques for rare tumor cell separation from body fluids have shown enormous promise in cancer detection and prognosis monitoring. This work established a high-throughput liquid biopsy platform with a high recovery rate and a high cell viability based on a previously reported 2.5D micropore-arrayed filtration membrane. Thanks to its high porosity (>40.2%, edge-to-edge space between the adjacent micropores <4 μm), the achieved filtration throughputs can reach >110 mL min-1 for aqueous samples and >17 mL min-1 for undiluted whole blood, only driven by gravity with no need for any extra pressure loading. The recoveries of rare lung tumor cells (A549s) spiked in PBS (10 mL), unprocessed BALF (10 mL) and whole blood (5 mL) show high recovery rates (88.0 ± 3.7%, 86.0 ± 5.3% and 83.2 ± 6.2%, respectively, n = 5 for every trial) and prove the high performance of this platform. Successful detection of circulating tumor cells (CTCs) from whole blood samples (5 mL) of lung cancer patients (n = 5) was demonstrated. In addition, it was both numerically and experimentally proved that a small edge-to-edge space was significant to improve the viability of the recovered cells and the purity of the target cell recovery, which was reported for the first time to the best of the authors' knowledge. This high-throughput technique will expand the detecting targets of liquid biopsy from the presently focused CTCs in whole blood to the exfoliated tumor cells (ETCs) in other large-volume clinical samples, such as BALF, urine and pleural fluid. Meanwhile, the technique is easy to operate and ready for integration with other separation and analysis tools to fulfill a powerful system for practical clinical applications of liquid biopsy.
液体活检技术可从体液中分离稀有肿瘤细胞，在癌症检测和预后监测方面显示出巨大的潜力。本工作在之前报道的 2.5D 微孔阵列过滤膜的基础上，建立了一种高通量液体活检平台，该平台具有高回收率和高细胞活力。由于其高孔隙率（>40.2%，相邻微孔之间的边缘到边缘空间<4 μm），仅在重力作用下，无需任何额外的压力加载，即可实现>110 mL min-1的水相样品和>17 mL min-1的未稀释全血的过滤通量。从 PBS（10 mL）、未经处理的 BALF（10 mL）和全血（5 mL）中加入的稀有肺肿瘤细胞（A549s）的回收率均很高（分别为 88.0 ± 3.7%、86.0 ± 5.3%和 83.2 ± 6.2%，每个试验重复 5 次），证明了该平台的高性能。成功从 5 例肺癌患者的全血样本（5 mL）中检测到循环肿瘤细胞（CTCs）。此外，通过数值和实验证明，小的边缘到边缘空间对提高回收细胞的活力和目标细胞回收的纯度非常重要，据作者所知，这是首次报道。这种高通量技术将液体活检的检测目标从目前全血中聚焦的 CTCs 扩展到其他大体积临床样本（如 BALF、尿液和胸腔积液）中的脱落肿瘤细胞（ETCs）。同时，该技术易于操作，并且易于与其他分离和分析工具集成，以实现用于液体活检实际临床应用的强大系统。
