School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
Department of Chemistry, University of Florida, Gainesville, FL, 32611-7200, USA.
Sci Rep. 2021 Jan 8;11(1):53. doi: 10.1038/s41598-020-79693-1.
We present a quantitative study of the metabolic activity of a single spheroid culture of human cancer cells. NMR (nuclear magnetic resonance) spectroscopy is an ideal tool for observation of live systems due to its non-invasive nature. However, limited sensitivity has so far hindered its application in microfluidic culture systems. We have used an optimised micro-NMR platform to observe metabolic changes from a single spheroid. NMR spectra were obtained by directly inserting microfluidic devices containing spheroids ranging from 150 [Formula: see text]m to 300 [Formula: see text]m in diameter in 2.5 [Formula: see text]L of culture medium into a dedicated NMR probe. Metabolite concentrations were found to change linearly with time, with rates approximately proportional to the number of cells in the spheroid. The results demonstrate that quantitative monitoring of a single spheroid with [Formula: see text] 2500 cells is possible. A change in spheroid size by 600 cells leads to a clearly detectable change in the L-Lactic acid production rate ([Formula: see text]). The consumption of D-Glucose and production of L-Lactic acid were approximately 2.5 times slower in spheroids compared to monolayer culture of the same number of cells. Moreover, while cells in monolayer culture were found to produce L-Alanine and L-Glutamine, spheroids showed slight consumption in both cases.
我们对人类癌细胞的单个球体培养物的代谢活性进行了定量研究。由于其非侵入性，NMR（核磁共振）光谱是观察活体系统的理想工具。然而，灵敏度有限迄今为止一直阻碍了它在微流控培养系统中的应用。我们使用优化的微 NMR 平台来观察单个球体的代谢变化。通过直接将直径为 150 至 300 [Formula: see text]m 的微流控装置插入含有球体的微流控装置，在 2.5 [Formula: see text]L 的培养基中，在专用的 NMR 探头中获得 NMR 光谱。发现代谢物浓度随时间呈线性变化，其速率与球体中的细胞数大致成正比。结果表明，有可能对具有[Formula: see text]2500 个细胞的单个球体进行定量监测。如果球体的大小增加 600 个细胞，则乳酸的产生速率([Formula: see text])会发生明显可检测的变化。与相同数量的细胞的单层培养相比，球体中的 D-葡萄糖消耗和 L-乳酸的产生速度大约慢 2.5 倍。此外，虽然在单层培养的细胞中发现产生 L-丙氨酸和 L-谷氨酰胺，但在两种情况下，球体都显示出轻微的消耗。
