Comparison of flow cytometry-based apoptosis detection methods for measuring of human native and cryopreserved spermatozoids viability

The aim of the study was to compare the ability of various media for cryopreservation of sperm to ensure their viability after thawing and to assess the possibility of using Narcissus pseudonarcissus lectin to determine the viability of native and cryopreserved human sperm by flow cytometry. Materials and methods. Used ejaculate 54 men aged 26 to 47 years, undergoing treatment for infertility. The control was a native ejaculate, which was also used for the in vitro fertilization procedure. Four parallel samples were frozen using various commercial media. After storage and thawing, spermatozoa viability was assessed by flow cytometry using three dyes and Narcissus pseudonarcissus lectin. Results. All assays showed that cryopreservation led to a twofold decrease of sperm viability, dye to the changes in the composition and properties of cell membrane, decrease in mitochondrial membrane potential, as well as the damages of acrosomal complex and nucleus. The lowest decrease in sperm viability was shown for Quinns advantage sperm freezing medium for cryopreservation. Conclusion. Flow cytometry makes it possible to evaluate with high efficiency sperm viability as the part of in vitro fertilization. The results of viability assessment using daffodil lectin make the prediction of in vitro fertilization outcome more accurate.