Development of Automation of Differential Leukocyte Counts by Use of Cytochemistry

Abstract

Abstract Development of automation in cytochemistry is reviewed. A variety of disciplines had to be merged to accomplish the following. Samples of anticoagulated whole blood are processed chemically in a continuous-flow system having precise proportioning of reagents and exact time sequences for reactions. While red blood cells are lysed, color contrast is developed in specific white blood cells. These are counted and differentiated by their light absorption and light scattering characteristics, typically at a rate of 500-2000 per second, in an automatic electro-optical device through which the cell suspension flows. The procedure is highly reproducible because it relies on physical constants rather than human judgment and because greater replication of sample is possible in the same time.