Flow cytometric reticulocyte counting with thioflavin T in a clinical hematology laboratory.

Flow cytometric measurement of reticulocyte counts, using the cationic dye thioflavin T, was implemented in a clinical hematology laboratory. Results obtained correlated well with manual reticulocyte counts using new methylene blue, but the reproducibility of counts done with the flow cytometer was much greater than that with manual counts. The new procedure permitted a reduction in laboratory staff, but required an intensive period of training for technologists. Utilization of the cytometer required about four hours per day of machine time for 60 counts, permitting implementation of other flow cytometric assays in the clinical laboratory.