Human oviductal cells reduce the incidence of apoptosis in cocultured mouse embryos

Abstract

Objective: To investigate the effect of human oviductal cell coculture on the incidence of apoptosis in mouse embryos. Design: Experimental laboratory study. Setting: University gynecology unit. Patient(s): Fallopian tubes were obtained from patients undergoing hysterectomy. Intervention(s): Mouse embryos were cocultured with human oviductal cells. Main Outcome Measure(s): Blastocyst development, allocation of inner cell mass (ICM) and trophectoderm (TE) in blastocyst, and apoptosis in embryos. Results: Oviductal cells significantly enhanced the blastulation (38%) and hatching rate (22%) of the cocultured zygotes. The corresponding values in medium alone culture were 21% and 9%, respectively. The cocultured embryos also had higher blastomere count at blastocyst stage ( P<0.005). This was due to increase in both the cell count of ICM ( P<0.05) and TE ( P<0.001). Coculture reduced the incidence of apoptosis in the cultured morula and blastocyst from 38% and 48% to 16% ( P<0.001) and 27% ( P<0.05), respectively. The number of apoptotic blastomeres per morula (1.5 ± 0.6; P<0.005) and blastocyst (2.3 ± 0.7; P<0.005) after coculture was also significantly lower than that of the corresponding control (morula, 2.1 ± 0.8; blastocyst, 3.5 ± 1.1). Conclusion(s): Human oviductal cells improved mouse embryo development partly by decreasing the incidence of apoptosis.