Changes in subcellular localization have been studied using immunofluorescence or Western blot analysis. However, these methods are difficult to quantify and cannot be easily applied to medium- or high-throughput workflows. Flow cytometry techniques have the potential to detect multiple factors across different cell types and analysis formats. 

Various challenges arise during the fluorescence-activated cell sorting (FACS) process, mainly intracellular FACS, where the staining of intracellular markers often depends on the biology of the target protein, leading to method variability. This collection aims to create a comprehensive library of methods and protocols related to flow cytometry, focusing on sample preparation, staining, and analysis to assist researchers working in this area.