Department of Radiation Oncology, Stanford University, Stanford, CA, 94305-5847, USA; Department of Mechanical Engineering, Stanford University, Stanford, CA, 94305-3011, USA.
Department of Radiation Oncology, Stanford University, Stanford, CA, 94305-5847, USA.
Biosens Bioelectron. 2021 Dec 15;194:113565. doi: 10.1016/j.bios.2021.113565. Epub 2021 Aug 13.
Flow-based cytometry methods are widely used to analyze heterogeneous cell populations. However, their use for small molecule studies remains limited due to bulky fluorescent labels that often interfere with biochemical activity in cells. In contrast, radiotracers require minimal modification of their target molecules and can track biochemical processes with negligible interference and high specificity. Here, we introduce flow radiocytometry (FRCM) that broadens the scope of current cytometry methods to include beta-emitting radiotracers as probes for single cell studies. FRCM uses droplet microfluidics and radiofluorogenesis to translate the radioactivity of single cells into a fluorescent signal that is then read out using a high-throughput optofluidic device. As a proof of concept, we quantitated [F]fluorodeoxyglucose radiotracer uptake in single human breast cancer cells and successfully assessed the metabolic flux of glucose and its heterogeneity at the cellular level. We believe FRCM has potential applications ranging from analytical assays for cancer and other diseases to development of small-molecule drugs.
流式细胞术方法广泛用于分析异质细胞群体。然而，由于荧光标记物体积庞大，常常干扰细胞内的生化活性，因此其在小分子研究中的应用仍然受到限制。相比之下，放射性示踪剂对其靶分子的修饰要求最小，并且可以以可忽略的干扰和高特异性来跟踪生化过程。在这里，我们引入了流式放射细胞术 (Flow Radiocytometry, FRCM)，它将当前的细胞术方法的范围扩大到包括β发射放射性示踪剂作为单细胞研究的探针。FRCM 使用液滴微流控技术和放射性荧光发生技术将单个细胞的放射性转化为荧光信号，然后使用高通量光电流体设备读取该信号。作为概念验证，我们定量测定了单个人类乳腺癌细胞中 [F]氟脱氧葡萄糖放射性示踪剂的摄取，并成功评估了葡萄糖的代谢通量及其在细胞水平上的异质性。我们相信 FRCM 具有广泛的应用前景，从癌症和其他疾病的分析检测到小分子药物的开发。
