Flow cytometric analysis of semen preparation, and assessment of acrosome reaction, reactive oxygen species production and leucocyte contamination in subfertile men

Reactive oxygen species (ROS) production, poor acrosome reaction ability, and leucocyte and round cell contamination of semen are associated with diminished male fertility. In addition to the assessment of these variables, the number of abnormal and round cells in semen preparation was studied by flow cytometry. Men with varying degree of fertility despite normal concentrations and motility of spermatozoa were investigated. Group 1 consisted of semen donor candidates (n=25), group 2 of patients with acceptable fertilization in vitro, but diminished fertility in vivo (n=56), and group 3 of patients with poor (<25%) fertilization in vitro (n=32). The subfertile men in groups 2 and 3 had lower concentrations and poorer rapid progressive motility of spermatozoa than the men in group 1. Using flow cytometry, the number of events in the round cell gate in the Percoll-prepared semen sample was higher in the subfertile men than in the donors, independently of the differences in other semen parameters. However, there were no significant differences between the groups in the number of round cells in native semen by microscopic analysis, or in ROS production or acrosome reaction. In conclusion, flow cytometric assessment of round cells may be a useful method in the investigation of male fertility.