Development of a Flexible Micro Spring Array device for viable circulating tumor

描述（由申请人提供）：开发一种柔性微弹簧阵列装置，用于有活力的循环肿瘤细胞富集、分析、原代培养和体外治疗反应测试。转移性癌症占癌症相关死亡的90%以上。癌症转移是恶性循环肿瘤细胞（CTCs）从原发肿瘤脱离，通过外周血扩散，然后侵入和扩散到远处器官的过程。在血液样本中检测ctc的根本挑战在于它们非常罕见，只需要在数十亿血细胞中检测少数肿瘤细胞的灵敏度。由于大多数实体肿瘤细胞是上皮细胞，并且几乎总是比正常血细胞更大、更坚硬，基于大小的分离已被证明是捕获CTC的有效方法。该项目的第一个目标是表征和优化一种新的柔性微弹簧阵列（FMSA）设备，用于从外周血样本中富集ctc。新颖的弹簧结构整合到设备设计中，最大限度地减少了ctc所经历的集中应力，并促进了它们的健康、生存和增殖。我们优化了该装置的间隙大小，可靠地实现85%以上的回收率，104对白细胞的富集，80%的活力，5mL新鲜血液在5分钟内在EDTA管中通量。这项技术便携、便宜、快速，而且比CellSearchTM更有效，CellSearchTM是目前FDA批准的唯一一种用于有限种类癌症的CTC枚举系统。在我们的初步研究中，我们还发现驱动压差对井的活力和增殖能力至关重要。安全操作压力比通常用于常规细胞过滤的压力低几个数量级。因此，我们的第二个目标是开发一个MEMS支持的自动低压控制系统，以促进FMSA器件。整个系统与FMSA装置一起，解决了40多年来广泛使用的常规过滤因细胞损伤和装置堵塞而无法富集活细胞的问题。更重要的是，FMSA系统能够捕获活的肿瘤细胞，这些细胞可用于原代培养和离体治疗药物疗效测试，这是本研究的第三个目标。成功捕获有活力的CTCs将促使建立系统和规程，使其成长为初级培养物。这将为在体外测试肿瘤细胞对多种抗癌药物的反应提供依据。如果证明

DESCRIPTION (provided by applicant): Development of a flexible micro spring array device for viable circulating tumor cell enrichment, analysis, primary culture and ex vivo therapeutic response test Metastatic cancer accounts for over 90% of cancer related deaths. Cancer metastasis is the process by which malignant circulating tumor cells (CTCs) detach from a primary tumor, spread through peripheral blood, then invade and proliferate in distant organs. The fundamental challenge of detecting CTCs in blood samples is the fact that they are so rare, requiring detection sensitivity of only a few tumors cells in billions of blood cells. Since the majority of solid tumor cells are of epithelial origin, and are almost always significantly larger and more rigid than normal blood cells, size based separation has been demonstrated as an effective method for CTC capture. The first goal of this project is to characterize and optimize a new flexible micro spring array (FMSA) device for the enrichment of CTCs from peripheral blood samples. The novel spring structures incorporated into the device design minimize concentrated stresses experienced by the CTCs and encourage their health, survival and proliferation. We have optimized the gap size of the device to reliably achieve over 85% recovery, 104 enrichment against leukocytes, 80% viability, and throughput of 5mL fresh blood in EDTA tube in 5 minutes. This technology is portable, cheap, fast, and more effective than CellSearchTM, which is the only current FDA approved system for CTC enumeration in a limited variety of cancers. In our preliminary study, we also found the driving differential pressure is critical for ell viability and proliferability. The safe operation pressure is orders of magnitude lower than the pressure normally used for conventional cell filtration. Thus our second goal is to develop a MEMS enabled automatic low pressure control system to facilitate the FMSA device. Together with the FMSA device, the whole system can solve the over 40 years' problem that widely used conventional filtration can't enrich viable mammalian cells because of cell damage and device clogging. More importantly, the FMSA system is capable of the capture of viable tumor cells that are available for primary culture and ex vivo therapeutic drug efficacy test, which is the third goal of the proposed study. The successful capture of viable CTCs will prompt the establishment of systems and protocols for their growth into a primary culture. This will provide the basis for testing the tumor cells' response to a variety of anticancer drugs ex vivo. If proven to be effective, a more specific and personalized treatment plan may be developed without having to unnecessarily expose a patient to the cost and toxic effects of chemotherapy. With further optimization for device flexibility and primary cell culture, and establishment of an automated low pressure control prototype, the FMSA enrichment system can be readily adapted for clinical usage. A pilot study of clinical samples obtained from our clinical collaborators will evaluate CTC detection, primary culture, and ex vivo drug efficacy tests with the FMSA system.