Improved quality of human embryos when co-cultured with human ampullary cells

Abstract

Cultured human, ampullary, epithelial cells obtained from fertile women undergoing hysterectomy were evaluated for the support of human embryonic cleavage and growth in vitro. Twelve patients provided 23 embryos for co-culture with subcultured ampullary cells grown in T6 + 15% patient's serum and 18 embryos for growth in T6 + 15% patient's serum alone (controls). Of embryos co-cultured with ampullary cells, 78% cleaved to the compacted embryo stage and 69% cavitated as compared with 50 and 33% respectively for controls (P less than 0.01). Only 30% of co-cultured embryos reached the expanded blastocyst and 26% underwent hatching as compared with 28% for both stages in controls. At the 2 - 4- and 6 - 8-cell stages, 91 and 87% of co-cultured embryos showed an absence or slight fragmentation as compared with 72 and 61% respectively for embryos grown in medium alone (P less than 0.01). None of the co-cultured embryos showed unequal-sized blastomeres while 22% of controls showed unequal cleavage. Embryos grown with ampullary cells cleaved slightly faster than controls. Scanning electron micrographs showed that ampullary cells collected from co-cultures were all of the secretory type with several microvilli and apical protrusions. It is clear that subcultured human ampullary cells support human embryonic cleavage and yield a reasonable number of good quality embryos up to the cavitation stage. Development past the expanded blastocyst and hatching stages seems to involve another critical phase with its own specific requirements.

Effect of various co-culture systems on embryo development in ovine

“…Indeed, in term of cleavage and speed of embryo development, co-culture system had not only superiority over cell free culture system (SOF) but also, except for OECs, embryo development was deteriorated by culturing in MSCs, EFCs, and late co-cultured groups (SOF-MSCs and SOF-EFCs) ( Table 1). This finding was contrasted to the majority of reports indicating the faster cleavage and higher blastocyst rate in co-culture systems (Bongso et al, 1989;Wiemer et al, 1989;Ellington et al, 1990;Smith et al, 1992;Wetzels et al, 1998;Joo et al, 2001). Though, there are some reports indicating no significant improvement in early embryogenesis (Tucker et al, 1995;Hu et al, 1998) and even reports indicating the adverse effects of co-culture on pre-implantation embryo development (Bernardi et al, 1996).…”

“…such as: higher and faster cleavage (Bongso et al, 1989), improved morphological appearance/ grade (Wiemer et al, 1989), increase of the average number of blastomeres (Smith et al, 1992), improved post-thaw blastomere survival of cryopreserved co-cultured embryos (Tucker et al, 1995), reduced apoptosis (Xu et al, 2000), higher blastocyst rate (Joo et al, 2001), facilitated hatching (Ellington et al, 1990), lower fragmentation rates, improved pregnancy rates (Wiemer et al, 1989), higher implantation ratio (Wetzels et al, 1998), and live births (Marcus and Brinsden, 1996). These effects are most pronounced with increasing the duration of co-culture (Wiemer et al, 1989), especially during the early cleavage stages which may be mediated by the expression of growth factors (Yeung et al, 1992).…”

Ultrastructural evaluation following catheterization of the fallopian tube with a hysteroscopic catheter

“…The status of the fallopian tube affects the quality of mammalian embryos (19)(20)(21). Major midcycle proteins in the human oviduct may protect the biochemical milieu of the fallopian tube during early embryonic development (22).…”

Effect of cryopreservation on the properties of human endometrial stromal cells used in embryo co-culture systems

“…To date, a wide variety of co-culture systems have been reported to have favorable effects on preimplantation embryo development such as improved growth [3,5,[7][8][9], morphological characteristics [10], and blastocyst development [11]; decreased incidence of fragmentation [3,5,12] and apoptosis [13]; and higher pregnancy [4,10] and delivery rates [14]. Among the broad range of somatic cell lines with welldetermined embryotrophic properties, Vero cells [15][16][17][18], cumulus-granulosa cells [19][20][21][22][23], and endometrial cells from the lining of the uterus [3-5, 11, 12, 24, 25] could be defined as the most popular and commonly used in clinical in vitro fertilization programs.…”