HUMAN SPERM FUNCTION AFTER COCULTURE WITH HUMAN FALLOPIAN TUBAL EPITHELIAL-CELL MONOLAYERS - IN-VITRO MODEL FOR STUDYING CELL-INTERACTIONS IN EARLY HUMAN CONCEPTION

It has been difficult to study the behavior of sperm in the tubal envi ronment in vivo. Human tubal epithelial cells were therefore cultured in vitro to simulate tubal conditions and human sperm function was ass essed in the presence of such cells in vitro. Ampullary epithelial cel l lines were established from fallopian tubes collected from premenopa usal women undergoing hysterectomy. Approximately 1 x 10(5) cells/mL f rom monolayers of the third passage were seeded with 1 mL of culture m edium into each well of 4-well plastic dishes. Sperm from 10 ejaculate s of 10 different oligoasthenozoospermic men 30-41 years of age were r ecovered by the swim-up method and 200,000 sperm from each ejaculate w ere added into each well at the time of cell seeding. Control wells we re treated the same but without cells. All dishes were incubated at 37 degrees C in 5% CO2, and sperm motility, acrosome reaction, and sperm -cell binding assessed at 1, 5, and 24 h. Curvilinear velocity and mea n amplitude of lateral head displacement were significantly different in ampullary cultures as compared with controls for all three time per iods: 1 h (67 +/- 5.2 vs 58 +/- 4.9 mu m/s, p < 0.05; 4.48 +/- 0.4 vs 3.29 +/- 0.3 mu m; p < 0.05), 5 h (75 +/- 5.8 vs 64 +/- 5.0 mu m/s, p < 0.05; 4.92 +/- 0.5 vs 3.68 +/- 0.3 mu m, p < 0.05), and 24 h (70 +/- 4.8 vs 59 +/- 4.2 mu m/s, p < 0.05; 4.36 +/- 0.4 vs 3.11 +/- 0.3 mu m , p < 0.05). The mean percentage of sperm undergoing the acrosome reac tion was not significantly different between experimental and control samples at 1, 5, and 24 hours (4.9 +/- 2.0% to 18.2 +/- 4.2% vs 4.8 +/ - 2.1% to 17.0 +/- 4.5%; p > 0.01). Approximately, 10 to 15% of sperm binding to epithelial cells was observed at 5 and 24 h. It would appea r that the increase in sperm motility may help to improve fertilizatio n rates in vitro fertilization.