PERCOLL DENSITY GRADIENT CENTRIFUGATION AND CONSECUTIVE FLOW-CYTOMETRY DO NOT IDENTIFY LEUKOCYTES AND LEUKOCYTE SUBTYPES IN EJACULATE SPECIMENS

This paper describes an attempt to establish a new combined method of leukocyte analysis in human ejaculate by Percoll density gradient cent rifugation and consecutive flow cytometry. As a first step, leukocyte separation was performed by Percoll density gradient centrifugation wi th consecutive enrichment of leukocytes, especially granulocytes, in t he 40%/60% and 60%/80% Percoll interfaces. Then these fractions were s tained with specific monoclonal antibodies and analysed in a Facscan f low cytometer. Flow cytometric analysis did not demonstrate identifiab le leukocyte populations, indicating a questionable cross-reaction wit h spermatozoal elements. Therefore, the combined technique of Percoll density gradient centrifugation and flow cytometric analysis were cons idered unsuitable for clinical leukocyte determination.