Baxter Laboratory in Stem Cell Biology, Department of Microbiology and Immunology, Stanford University, Stanford, California, USA.
Cytometry A. 2013 May;83(5):483-94. doi: 10.1002/cyto.a.22271. Epub 2013 Mar 19.
Mass cytometry uses atomic mass spectrometry combined with isotopically pure reporter elements to currently measure as many as 40 parameters per single cell. As with any quantitative technology, there is a fundamental need for quality assurance and normalization protocols. In the case of mass cytometry, the signal variation over time due to changes in instrument performance combined with intervals between scheduled maintenance must be accounted for and then normalized. Here, samples were mixed with polystyrene beads embedded with metal lanthanides, allowing monitoring of mass cytometry instrument performance over multiple days of data acquisition. The protocol described here includes simultaneous measurements of beads and cells on the mass cytometer, subsequent extraction of the bead-based signature, and the application of an algorithm enabling correction of both short- and long-term signal fluctuations. The variation in the intensity of the beads that remains after normalization may also be used to determine data quality. Application of the algorithm to a one-month longitudinal analysis of a human peripheral blood sample reduced the range of median signal fluctuation from 4.9-fold to 1.3-fold.
液质联用技术使用原子质谱仪结合同位素纯报告元素，目前可对每个单细胞进行多达 40 个参数的测量。与任何定量技术一样，都需要有质量保证和标准化协议。就液质联用而言，由于仪器性能的变化以及计划维护之间的间隔而导致的信号随时间的变化必须加以考虑，然后进行标准化。在这里，将样品与嵌入镧系金属的聚苯乙烯珠混合，从而可以在多天的数据采集过程中监测液质联用仪器的性能。这里描述的方案包括在液质联用仪上同时测量珠子和细胞，随后提取基于珠子的特征，以及应用一种算法来校正短期和长期信号波动。归一化后剩余的珠子强度变化也可用于确定数据质量。该算法在对人类外周血样本进行一个月的纵向分析中的应用，将中位数信号波动幅度从 4.9 倍降低到 1.3 倍。
