Coculture of Human Sperm With Bovine Oviduct Epithelial Cells Decreases Sperm Chromatin Structural Changes Seen During Culture in Media Alone

Abstract

Objective: To compare sperm chromatin structural changes seen in media only culture or in coculture with bovine oviduct epithelial cells. Design: Three freshly ejaculated and three cryopreserved sperm samples in media culture or in oviduct epithelial cell coculture. Sperm in each treatment were evaluated by the sperm chromatin structure assay during a 72-hour time course. Setting: An academic research laboratory. Patient(s): Normospermic donors with children. Intervention(s): Semen collection through masturbation after 48 hours of abstinence. Main Outcome Measure(s): The sperm chromatin structure assay using flow cytometry to detect the susceptibility of sperm in either treatment to denaturation of DNA in situ. Result(s): The sperm chromatin structure assay data differed for sperm type (fresh or cryopreserved), over time, and between treatments within 6 hours of culture. In oviduct epithelial cell coculture, fresh sperm chromatin structure assay values for fresh sperm were stable, whereas in control medium higher chromatin degeneration levels were seen by 10 hours. For cryopreserved sperm, chromatin degeneration had increased by 1 hour postthaw in both treatments, although levels were higher in the control treatment thereafter. Conclusion(s): Sperm chromatin structural changes occur over time in culture. Such changes were observed within 2 hours for cryopreserved sperm. Coculture of sperm with oviduct epithelial cells results in a stabilizing effect for sperm against chromatin changes.