• Journal of Embryo Transfer
• /
• v.11 no.3
• /
• pp.201-210
• /
• 1996

This experiment was carried out to evaluate the effect of early mouse embryonic development in vitro by co-culture with bovine and porcine oviductal epithelial cells (BOEC and POEC). The 2-cell embryos were collected from the oviducts of the superovulated and mated cultured in D-PBS /15% FCS at 48 hours after hCG injection. The in vitro developmental rate of blastocyst formation in the embryos were examined under the fllowing treatments; 1) TCM 199 added 15% HCS, 2) Ham's F-10 added 15% HCS, 3) MediCult IVF medium, 4) TCM 199 added 15% HCS + BOEC, 5) TCM 199 added 15% HCS + POEC, 6) Ham's F40 added 15% HCS + BOEC, 7) Ham's F-10 added 15% HCS + POEC,8) MediCult IVF medium + BOEC, 9) MediCult IVF medium + POEC. For a comparative study of in vitro development for 96 hours after hCG injection, were cultured with oviductal epithelial cell and media only. The obtained results were 2-cell embryos developed to the blastocyst stage in TCM 199, Ham's F-10 and MediCult IVF medium at the rates of 84.4,83.2 and 81.6%. respectively. The higher developmental rates(91~97%) of blastocyst formation was appeared when the embryos were co-cultured with a monolayer of bovine or porcine oviductal epithelial cells in TCM 199 or Ham's F-10 and MediCult IVF media. No significant difference in developmental rates was shown between bovine and porcine oviductal epithelial cells but significant difference in co-culture system in comparison between media only system and co-cultures. In conclusions, oviductal epithelial cells, BOEC and POEC, when co-culture with mouse early embryos improved the rates of development, blastocyst and hatching. Therefore, it is suggested that co-culture system using oviductal epithelial cells improve early embryonic developtnent in mouse.

• Clinical and Experimental Reproductive Medicine
• /
• v.23 no.1
• /
• pp.95-102
• /
• 1996

This study was performed to investigate the effect of human follicular fluid (HFF) on development of mouse embryos, for evaluating the suitability of HFF as a substitutive material of human fetal cord serum in ART program. The various concentrations of HFF were added into the culture medium and the effects of HFF concentrations were examined to identify the optimal concentration of HFF for embryo development. The potency of HFF in improving embryo development was compared to that of other protein supplement. Collected HFFs were classified with the maturity of the containing oocytes; mature, immature, atretic, and then the effects of the classified HFFs on embryo development were examined. Also, HFF was separated into the low (<30,000 Da) and high (>30,000 Da) molecular weight fractions and the effects of the fractions on embryo development were investigated. The highest development rate was found in culture medium supplemented with 20% HFF, bnt this rate was reversely reduced at the concentrations of HFF higher than 20%. The development rates to the blastocyst, hatching blastocyst, attachment and outgrowth cultured in mature HFF was significantly higher than those in immature and atretic HFF, and mean cell number in blastocyst was higher in mature HFF than in immature and atretic HFF. The development rates of mouse embryos according to protein sources were significantly higher in HFF than in fetal cord serum (FCS), maternal serum (MS) and bovine serum albumin (BSA), and mean cell number in blastocyst cultured in HFF was higher than that in FCS, MS and BSA. The development rates of embryo and mean cell number in blastocyst cultured in high molecular weight fraction of HFF were higher than those in low molecular weight fraction, but the results of high molecular weight fraction were lower than those of whole HFF. Therefore, these results indicated that human mature follicular fluid was useful for improving the development of mouse embryos, which suggests a possibility that HFF also may be used efficiently for improving the culture condition in human ART program as a protein supplement.

• Clinical and Experimental Reproductive Medicine
• /
• v.28 no.1
• /
• pp.55-63
• /
• 2001

Objectives: This study was carried out to evaluate the effects of embryonic stage, cryoprotectant, and freezing-thawing method on the rates of survival and development of the cryopreserved mouse early embryo and finally to establish the cryopreservation method of surplus embryos obtained during assisted reproductive technology (ART). Materials and Methods: Two to eight cell embryos were obtained from oviducts of mated $F_1$ hybrid female mice superovulated by pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Two-step 1,2-propanediol (PROH), dimethylsulfoxide (DMSO) and 4-step PROH DMSO were used as cryoprotectant and dehydration and rehydration method of embryos, and slow-cooling or rapid-cooling method was used as frozen program. The survival rates of embryos were measured after thawing and rehydration, and the developmental rates of embryos were compared and observed during culturing embryos for 24, 48, 72, 96 hrs. Results: As for the survival and development rates of embryos according to embryonic stage, the survival rate of 2 cell stage in PROH and DMSO was significantly higher than 4-8 cell (64.5% versus 62.1 %,79.7% versus 73.2%) (p<0.01, p<0.01), but the development rates of 4-8 cell embryos in PROH and DMSO were significantly higher than 2 cell embryos for whole culture period (p<0.01) and the development rates of 4-8 cell embryos in PROH were significantly higher than 2 cell embryos in DMSO (p<0.01). As for the survival and development rates of embryos according to cryoprotectant, the survival rate of 2 cell embryo in DMSO was significantly higher than that in PROH (74.4% versus 64.5%) (p<0.01), whereas the development rate of embryos was not differ till 24 hrs. The developmen1 rate from morular to hatching blastocyst, however, was significantly higher in PROH than in DMSO during 48 hr (p<0.01). The survival rate of 4-8 cell embryo was 62.1% in PROH and 73.2% in DMSO. The development rates of embryo in PROH were significantly higher for whole culture periods (p<0.01, 0.05). In respect to the effect of freezing and thawing program on the survival and development rates of embryos, method of slow cooling and rapid thawing was more effective than that of rapid cooling and rapid thawing. Conclusions: The survival rate of embryo in 2 cell stage was higher than in 4-8 cell stage, and PROH appears more effective cryoprotectant than DMSO because PROH showed better development rates of embryos in 2 and 4-8 cell stage. Moreover, slow cooling and rapid thawing method was considered as the best cryopreservation program.

• The Korean Journal of Zoology
• /
• v.39 no.4
• /
• pp.352-361
• /
• 1996

The c-myc proto-onco9ene, one of the immediately early genes, is involved in ceflular proliferation and differentiation, and its biologleal function is regulated hy dimerization with a heterodimeric partner, myn. In the present study, gene expression patterns of c-myc and myn during mouse preimplantation embryo development were examined using a semi-quantitative reverse transcription-poiymerase chain reaction (RT-PCR). Myn transcripts were rather constitutively expressed throughout embryonic stages with a slight increase only at biastocyst stage. in contrast, expression of c-myc transcripts wm developmental stage-'pedfic. The c-myc transcripts were detected at 1-cell stage, declined abruptly at 2-cell stage and then increased gradually at blastocyst stage. To examine the possible role of myn during preimpiantation mouse embryo development, two myn antisense oligonucleotides spanning the tail of zipper dognain (myn2; 20-mer) and the second helix domain (myn3; 20-mer) were microinjected into the fertilized 1-cellembryos. Microinjection of myn2 and myn3 resulted in developmental tion at morula/biastocyst transition stage, leading to the fiagentation of embryos. Talien together, these results suggest that c-myc and its heterodimeric partner, myn, are differentially expressed In a developmental stage-dependent manner, and myn may play an important role in mouse preimpiantation embryo development.

• Clinical and Experimental Reproductive Medicine
• /
• v.24 no.2
• /
• pp.233-239
• /
• 1997

Embryos of most mammalian species grown in vitro would undergo developmental arrest at the approximate time of genomic activation. Stage-specific cell block and the resulting rapid loss of embryo viability in conventional culture media have limited the duration for which embryos may be cultured prior to transfer. As a result, embryos are usually transferred to the uterus at the 4-to 8-cell stage to avoid the loss of viability associated with long-term in vitro culture. Early transfer has led to asynchrony of the endometrium-trophectoderm interaction at the time of implantation and a resultant reduction in the rate of implantation. To overcome these problems, a variety of co-culture systems has been devised in which embryos can develop for a longer period prior to embryo transfer. Vero cells, derived from African green monkey kidney, share a common embryologic origin with cells from the genital tract. In addition, they are potentially safe to use, since they are highly controlled for viruses and other contaminants. Therefore, co-culture using Vero cells has been widely utilized to enhance embryo viability and development, although not without controversies. We thus designed a series of experiments to demonstrate whether Vero cells do indeed enhance mouse embryo development as well as to compare the efficacy of co-culturing mouse 1-cell embryos on Vero cell monolayer in both Ham's F-10 and human tubal fluid (HTF) culture media. 1-cell stage ICR mouse embryos were cultured either in the presence of Vero cells (Group A) or in conventional culture medium alone (Group B). In Ham's F-10 significantly more 3-to-8cell embryos developed in group A than group B (59.8 versus 10.0%; p<0.01). In contrast, there was no significant difference in embryonic development both group A and group B in HTF. However, significant differences were noted only in later embryonic stage (13 and 0%; p<0.05 of group A and B respectively, hatching or hatched). In Ham's F-10, we also could observe the beneficial effect of Vero cell on hatching process (70.7 and 42.1%; p<0.05 of group A and group B respectively).

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2003.11a
• /
• pp.87-87
• /
• 2003

Taurine (2-aminoethanesulfonic acid, $^{+}NH_3CH_2CH_2{SO_3}^{-}$) is endogenous $\beta$-amino acid which is essential in fetal nutrition and development and is present in abundant quantities in several tissues of fetus. In utero, taurine deficiency causes abnormal development and abnormal function of brain, retina, kidney and myocardium. Thus, transfer of taurine into fetus is important during embryonic development. Taurine transporter (TauT) has 12 hydrophobic membrane -spanning domains, which is typical of the $Na^{+}$- and $Cl^{-}$-dependent transporter gene family. Among the various biosynthetic enzymes of taurine, cysteine sulfinic acid decarboxylase (CSD) is the rate-limiting enzyme for biosynthesis of taurine. However, the enzyme activities of taurine biosynthesis are limited in early stage of embryonic development. To analyze the expression period of TauT and CSD during embryonic development, we have investigated the gene expression of TauT and CSD using reverse transcriptase polymerase chain reaction (RT-PCR) in mouse and chicken embryos. RT-PCR anaylsis revealed that both TauT and CSD mRNAs were already expressed at Day-4.5 in mouse embryo. In chicken whole embryo, TauT and CSD mRNAs began to appear on developing times of 48 hrs and 12 hrs, respectively. TauT mRNA was detected in the organs of heart, brain and eye of the day-3 chicken embryo. Our data show that TauT and CSD mRNAs were expressed in early stage of embryonic development.

• Clinical and Experimental Reproductive Medicine
• /
• v.41 no.2
• /
• pp.47-61
• /
• 2014

Stored maternal factors in oocytes regulate oocyte differentiation into embryos during early embryonic development. Before zygotic gene activation (ZGA), these early embryos are mainly dependent on maternal factors for survival, such as macromolecules and subcellular organelles in oocytes. The genes encoding these essential maternal products are referred to as maternal effect genes (MEGs). MEGs accumulate maternal factors during oogenesis and enable ZGA, progression of early embryo development, and the initial establishment of embryonic cell lineages. Disruption of MEGs results in defective embryogenesis. Despite their important functions, only a few mammalian MEGs have been identified. In this review we summarize the roles of known MEGs in mouse fertility, with a particular emphasis on oocytes and early embryonic development. An increased knowledge of the working mechanism of MEGs could ultimately provide a means to regulate oocyte maturation and subsequent early embryonic development.

• Journal of Embryo Transfer
• /
• v.6 no.2
• /
• pp.47-51
• /
• 1991

This study investigated full-term development potential of ultrarap idly frozen and thawed mouse 2-cell embryos. Mouse 2-cell embryos, dehydrated by exposure to freezing medium, were directly immersed into liquid nitrogen and thawed in 37$^{\circ}C$ water. The embryos that were frozen and thawed were cultured in uitro and transferred to foster mothers to examine there developmental potential. As a result, the frozen-thawed 2-cell embryos developed to blastocysts in vitro as a similar rate as control 2-cell embryos did(in vitro 2-cell, 86.4%; in vivo 2-cell, 90.9%; solution control, 89.9%; control, 89.7%). Normal live young were obtained from transfer of frozen-thawed embryos to the oviduct and uterus of pseudopregnant recipients (3l.4~56.7%).

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2002.11a
• /
• pp.102-102
• /
• 2002

Heparin-bindin epidermal growth factor (HB-EGF) is one of the EGF family to be expressed at the time of implantation in the mouse uterus. Although HB-EGF has been shown to stimulate the development of embryo and uterus in the mouse, its correlation between cell adhesion molecules remains undefined. Integrin $\alpha$$_{ν}$$\beta$$_3$, one of the cell adhesion molecules, is an important mediator of cell-substratum and cell-cell adhesion in implantation. In the present studies, we investigated the effects of HB-EGF on the embryonic development, initiation of implantation and expression of integrin $\alpha$$_{ν}$$\beta$$_3$ in in vitro culture, blocking of HB-EGF, RT-PCR and immunofluores cence analysis. The results showed that HB-EGF significantly improved the developmental rate of hatched embryos (24.1%, p<0.01) and outgrowth embryos (42.5%, p<0.01). On the other hand, this growth factor showed no offset before the hatching embryonic stage. Analysis of RT-PCR showed that HB-EGF upregulated the expression level of integrina $\alpha$$_{ν}$$\beta$$_3$ subunit genes on the preimplantation embryo and outgrowth of blastocyst (120hr and 144hr after hCG injection). Immunofluorescence analysis showed that the integrin $\alpha$$_{ν}$$\beta$$_3$ subunits localized at the pericellular borders and cell-cell contact areas. Increase in fluorescence intensity was observed in the HB-EGF treated embryos. Intrauterine injection of an anti-HB-EGF antiserum at day 3 significantly decreased the number of implantation sites (14.4, p<0.01) and significantly increased the number of recovered embryos(6.4, p<0.05) at day 5. From these results, it imply that HB-EGF improve the embryo development and accelerated the expression of integrin $\alpha$$_{ν}$$\beta$$_3$ in the preimplantation mouse embryos.

• Clinical and Experimental Reproductive Medicine
• /
• v.27 no.4
• /
• pp.381-385
• /
• 2000

Objective: To verify the effect of two forms (growth factor and growthfactor-reduced) of solubilized Matrigel on the development in mouse preimplantation embryos. Methods: Late 2-cell stage eggs were cultured through the blastocyst stage in the presence of GF- or GFR-Matrigel (0.5%, v/v). Morphological development, cell number and % apoptotic nuclei of blastocyst were measured by Roecst staining and TUNEL of nuclei. Results: Morphological development, number of cells per embryo was significantly increased in the presence of GF- or GFR-Matrigel. Culture of the embryos in the GF-Matrigel gave the best result. Conclusion: Low concentration of solubilized Matrigel improved development of mouse embryos regardless of growth factor content of the Matrigel. Growth factors and extracellular matrix protein included in the Matrigel synergistically potentiated the development of mouse embryos.