Flow cytometry of human reticulocytes based on RNA fluorescence

A fluorescent staining procedure based on pyronin Y is described. The technique has been used to stain RNA in human reticulocytes for subsequent flow analysis and sorting. Histograms of fluorescence values of mature red blood cells and reticulocytes obtained by flow cytometry of stained blood samples, contain more information than offered by conventional methods for counting reticulocytes. Analysis of the fluorescence histograms provides new descriptive parameters of the reticulocyte populations. The potential importance of this method in experimental and routine hematology is illustrated for a number of clinical cases.