Flowcytometry analysis of lysosomal pulldown with anti-TMEM192 magnetic beads from PBMCs

We describe a method that allows the staining of intact lysosomes using lysotracker for flow cytometry analysis. The analysis can provide a quantitative indication of the level of enrichment of the organelle immunoprecipitation (% of lysososomal+ beads) and can be used as a quality control check for the purity of the immunoprecipitated lysoIPs. Since only a small fraction of the immunoprecipitated material is needed for flow cytometry, this technique can be coupled with other assays, like western blotting or proteomics. While this protocol is focused on the staining and detection of lysosomes, it can be easily modified to analyse different organelles by changing the staining procedure and adjusting the parameters of the cytometer.