Attachment staining: A novel method for flow cytometric quantitation of protein expression in limited numbers of adherent cells

Abstract

Measurement of protein expression in adherent cells in culture by flow cytometry, although potentially a very powerful method, has so far found limited application. Where the method has been applied successfully, cells have been resuspended for analysis either prior to experimental treatment or before immunostaining. Such approaches have several limitations and do not permit analysis of limited numbers of cells. Here we describe a method of attachment staining which allows protein expression in a few thousand adherent cells to be analyzed by flow cytometry. The method has been successfully used for the measurement of growth factor-induced C-Fos protein expression and measurement of c-Fos expression in samples of < 3,000 adherent fibroblasts.