COCULTURE OF HUMAN SPERMATOZOA WITH REPRODUCTIVE-TRACT CELL MONOLAYERS CAN ENHANCE SPERM FUNCTIONS BETTER THAN COCULTURE WITH VERO CELL MONOLAYERS

Purpose: In order to develop a better system for support of human sper m function in vitro, we conducted studies to evaluate whether reproduc tive tract cells are better than non-reproductive tract cells as art a djunt in that regard. Methods: Human spermatozoa were cocultured with Vero cells, with human oviduct cells and endometrial cells, and withou t cells (control) for either 1, 4, or 24 hr Sperm motility was then an alyzed with a computer-aided sperm analyzer (CASA-Hamiliton Thron, HTM IVOS Motility Analyzer). Aliquots of spermatozoa incubated for 24 hr were also stained with Hoechst 33258 and FITC-PNA to evaluate the stat us of acrosome in live cells. Results: Significant differences (P < 0. 05) between the oviduct cell and the control groups after 24 hr were e vident in the curvilinear velocity (VCL) (81.4 +/- 13.4 vs 60.0 +/- 14 .1 mu m/sec) and amplitude of lateral head displacement (ALH) (5.2 +/- 0.6 vs 4.1 +/- 0.5 mu m). The incidence of acrosome reaction of live sperm was significantly higher in the endometrial cell group than in t he controls (25.4 +/- 9.9 vs 6.6 +/- 2.4%; P < 0.001). Conclusions: Co culture with human reproductive tract cells seems to improve some func tional parameters of human spermatozoa. Coincubation with such cell li nes, especially oviduct cells, might be a feasible approach to optimiz ation of human spermatozoa for assisted fertilization using subfertile or frozen-thawed samples. We think coincubating human spermatozoa wit h a human reproductive tract cell line, especially oviduct cells, migh t be a feasible approach in preparing human spermatozoa for assisted f ertilization in subfertile and frozen-thawed semen samples.