Sensitive and Specific Biomimetic Lipid Coated Microfluidics to Isolate Viable Circulating Tumor Cells and Microemboli for Cancer Detection

Here we presented a simple and effective membrane mimetic microfluidic device with antibody conjugated supported lipid bilayer (SLB) “smart coating” to capture viable circulating tumor cells (CTCs) and circulating tumor microemboli (CTM) directly from whole blood of all stage clinical cancer patients. The non-covalently bound SLB was able to promote dynamic clustering of lipid-tethered antibodies to CTC antigens and minimized non-specific blood cells retention through its non-fouling nature. A gentle flow further flushed away loosely-bound blood cells to achieve high purity of CTCs, and a stream of air foam injected disintegrate the SLB assemblies to release intact and viable CTCs from the chip. Human blood spiked cancer cell line test showed the ~95% overall efficiency to recover both CTCs and CTMs. Live/dead assay showed that at least 86% of recovered cells maintain viability. By using 2 mL of peripheral blood, the CTCs and CTMs counts of 63 healthy and colorectal cancer donors were positively correlated with the cancer progression. In summary, a simple and effective strategy utilizing biomimetic principle was developed to retrieve viable CTCs for enumeration, molecular analysis, as well as ex vivo culture over weeks. Due to the high sensitivity and specificity, it is the first time to show the high detection rates and quantity of CTCs in non-metastatic cancer patients. This work offers the values in both early cancer detection and prognosis of CTC and provides an accurate non-invasive strategy for routine clinical investigation on CTCs.本研究报道了一款简便高效的仿生膜微流控装置，其搭载抗体偶联支撑脂质双层（supported lipid bilayer, SLB）“智能涂层”，可直接从各分期临床癌症患者的全血中捕获存活的循环肿瘤细胞（circulating tumor cells, CTCs）与循环肿瘤微栓子（circulating tumor microemboli, CTM）。该非共价结合的SLB可促进脂质锚定抗体与CTC抗原的动态簇集，并凭借其抗污特性最大限度减少非特异性血细胞的滞留。温和流场可进一步冲洗掉松散结合的血细胞，以获得高纯度的CTCs；而注入的气泡流可裂解SLB组装体，从芯片中释放出完整且存活的CTCs。加标癌细胞系的人血实验显示，该装置回收CTCs与CTM的总效率约为95%。死活染色检测结果表明，回收的细胞中至少86%仍保持活性。通过采集2 mL外周血，对63名健康受试者与结直肠癌患者的CTCs与CTM计数结果显示，其数量与癌症进展呈正相关。综上，本研究开发了一种基于仿生原理的简便高效策略，可回收存活的CTCs用于计数分析、分子分析以及长达数周的体外培养。凭借高灵敏度与特异性，本研究首次在非转移性癌症患者中实现了CTCs的高检出率与定量检测。该工作可为CTCs相关的癌症早期检测与预后评估提供重要价值，并为CTCs的常规临床检测提供一种精准的非侵入性策略。