Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy.
Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy.
Biosens Bioelectron. 2022 Sep 15;212:114401. doi: 10.1016/j.bios.2022.114401. Epub 2022 May 18.
The detection of extracellular pH at single cell resolution is challenging and requires advanced sensibility. Sensing pH at high spatial and temporal resolution might provide crucial information in understanding the role of pH and its fluctuations in a wide range of physio-pathological cellular processes, including cancer. Here, a method to embed silica-based fluorescent pH sensors into alginate-based three-dimensional (3D) microgels tumour models, coupled with a computational method for fine data analysis, is presented. By means of confocal laser scanning microscopy, live-cell time-lapse imaging of 3D alginate microgels was performed and the extracellular pH metabolic variations were monitored in both in vitro 3D mono- and 3D co-cultures of tumour and stromal pancreatic cells. The results show that the extracellular pH is cell line-specific and time-dependent. Moreover, differences in pH were also detected between 3D monocultures versus 3D co-cultures, thus suggesting the existence of a metabolic crosstalk between tumour and stromal cells. In conclusion, the system has the potential to image multiple live cell types in a 3D environment and to decipher in real-time their pH metabolic interplay under controlled experimental conditions, thus being also a suitable platform for drug screening and personalized medicine.
在单细胞分辨率下检测细胞外 pH 值具有挑战性，需要先进的灵敏度。以高时空分辨率感知 pH 值可能会提供关键信息，有助于理解 pH 值及其波动在广泛的生理病理细胞过程中的作用，包括癌症。在这里，提出了一种将基于硅的荧光 pH 传感器嵌入藻酸盐基三维 (3D) 微凝胶肿瘤模型中的方法，并结合了一种用于精细数据分析的计算方法。通过共聚焦激光扫描显微镜对 3D 藻酸盐微凝胶进行活细胞延时成像，并监测体外 3D 单培养和肿瘤和基质胰腺细胞的 3D 共培养物中细胞外 pH 值的代谢变化。结果表明，细胞外 pH 值是细胞系特异性和时间依赖性的。此外，还检测到 3D 单培养物与 3D 共培养物之间的 pH 值存在差异，这表明肿瘤细胞和基质细胞之间存在代谢串扰。总之，该系统具有在 3D 环境中对多种活细胞类型进行成像的潜力，并能够实时解析其在受控实验条件下的 pH 值代谢相互作用，因此也是药物筛选和个性化医疗的合适平台。
