The Basics of Staining for Cell Surface Proteins

Abstract

A flow cytometer detects fluorescent light given off by cells. Although flow cytometry can be used to analyze the intrinsic fluorescence of cells (“auto fluorescence”), cells differ from each other in many ways that do not result in auto fluorescent variation. For this reason, staining of cells is usually required to make biochemical variation “visible” to the photodetectors of a flow cytometer. By making use of fluorescent stains that are specific for different molecules, we can use a flow cytometer to assay a large array of different cell constituents.