P-178 The interaction between spermatozoa and cumulus cells: a more physiological approach to the selection of good quality spermatozoa for assisted reproduction

Abstract Study question Does selection by cumulus cells (CCs) improve sperm quality in terms of acrosome integrity and mitochondrial functionality compared to standard techniques? Summary answer The sperm-CCs interaction method appears to be effective in selecting sperm with an intact acrosome and functioning mitochondria What is known already In nature, the selection of the best quality sperm is very demanding and involves high morphological qualities and dynamic features. Semen preparation in ART has long been carried out using either the swim-up or density gradient method; although both methods provide motile sperm, they cannot really replicate the physiological selection processes. As a result, several methods have been proposed to mimic the natural selection that occurs in the female reproductive tract, allowing the most competent sperm to provide the paternal contribution to the zygote. However, the literature on these techniques is limited and does not provide consistent conclusions Study design, size, duration Proof-of-principle study conducted at the New Fertility Group (NFG) in Rome and the Department of Molecular and Developmental Medicine at the University of Siena (Italy) from July 2022 to December 2022, including 9 semen samples. Comparison of the CCs selection model with the standard swim-up by assessing mitochondrial and acrosome integrity. In addition, mitochondrial activity was assessed by oxygraphic analysis in spermatozoa exposed to immortalised human granulosa cells (hGL5) compared to standard swim-up sorted spermatozoa Participants/materials, setting, methods The CCs-model was prepared by running two channels of medium, one with CCs (study group) and one with medium alone (control). Spermatozoa were added to each channel and incubated at 37 °C for 1 hour. Moreover, spermatozoa were also added on hGL5 and incubated for 1.5h. The collected spermatozoa were compared with controls for acrosomal integrity, assessed by FITC-labelled PSA, and mitochondrial membrane potential, assessed by Mitotracker. Finally, sperm oxygen uptake was measured by oxygraphic analysis Main results and the role of chance Assessment of sperm acrosome integrity showed a higher percentage of responding acrosomes in the CCs model compared to swim-up and controls (61% ± 0.3; 39% ± 0.4; 19% ± 0.4 p