Percoll density gradient centrifugation and consecutive flow cytometry do not identify leukocytes and leukocyte subtypes in ejaculate specimens.

Abstract

This paper describes an attempt to establish a new combined method of leukocyte analysis in human ejaculate by Percoll density gradient centrifugation and consecutive flow cytometry. As a first step, leukocyte separation was performed by Percoll density gradient centrifugation with consecutive enrichment of leukocytes, especially granulocytes, in the 40%/60% and 60%/80% Percoll interfaces. Then these fractions were stained with specific monoclonal antibodies and analysed in a Facscan flow cytometer. Flow cytometric analysis did not demonstrate identifiable leukocyte populations, indicating a questionable cross-reaction with spermatozoal elements. Therefore, the combined technique of Percoll density gradient centrifugation and flow cytometric analysis were considered unsuitable for clinical leukocyte determination.