Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan, 430072, China.
Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, People's Republic of China.
Biomed Microdevices. 2020 Oct 20;22(4):75. doi: 10.1007/s10544-020-00531-2.
Being easy, safe and reliable, non-invasive prenatal diagnosis (NIPD) has been greatly pursued in recent years. Holding the complete genetic information of the fetus, fetal nucleated red blood cells (fNRBCs) are viewed as a suitable target for NIPD application. However, effective separating fNRBCs from maternal peripheral blood for clinic use still faces great challenges, given that fNRBCs are extremely rare in maternal blood circulation. Here, by combining the high-throughput inertial microfluidic chip with multifunctional microspheres as size amplification, we develop a novel method to isolate fNRBCs with high performance. To enlarge the size difference between fNRBCs and normal blood cells, we use the gelatin coated microspheres to capture fNRBCs with anti-CD147 as specific recognizer at first. The size difference between fNRBCs captured by the microspheres and normal blood cells makes it easy to purify the captured fNRBCs through the spiral microfluidic chip. Finally, the purified fNRBCs are mildly released from the microspheres by enzymatically degrading the gelatin coating. Cell capture efficiency about 81%, high purity of 83%, as well as cell release viability over 80% were achieved using spiked samples by this approach. Additionally, fNRBCs were successfully detected from peripheral blood of pregnant women with an average of 24 fNRBCs per mL, suggesting the great potential of this method for clinical non-invasive prenatal diagnosis.
非侵入性产前诊断（NIPD）具有简便、安全、可靠的特点，近年来受到了广泛关注。胎儿有核红细胞（fNRBCs）携带胎儿完整的遗传信息，被视为 NIPD 应用的理想靶细胞。然而，由于 fNRBCs 在母体外周血循环中极其稀少，要将其从母体外周血中有效分离出来并应用于临床仍然面临巨大挑战。在这里，我们结合高通量惯性微流控芯片和多功能微球作为尺寸放大技术，开发了一种从母体外周血中高效分离 fNRBCs 的新方法。为了扩大 fNRBCs 与正常血细胞之间的尺寸差异，我们首先使用包被明胶的微球捕获 fNRBCs，并用抗-CD147 作为特异性识别物。由于微球捕获的 fNRBCs 与正常血细胞之间的尺寸差异，很容易通过螺旋微流控芯片对捕获的 fNRBCs 进行纯化。最后，通过酶降解明胶涂层，从微球上温和释放纯化的 fNRBCs。该方法在添加样本时的细胞捕获效率约为 81%，纯度为 83%，细胞释放存活率超过 80%。此外，还成功地从孕妇外周血中检测到了 fNRBCs，平均每个样本有 24 个 fNRBCs，表明该方法在临床非侵入性产前诊断中有很大的应用潜力。
