• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2006.10a
• /
• pp.44-45
• /
• 2006

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2006.10a
• /
• pp.76-77
• /
• 2006

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2004.10a
• /
• pp.45-45
• /
• 2004

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2004.10a
• /
• pp.98-99
• /
• 2004

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2005.10a
• /
• pp.41-41
• /
• 2005

• Clinical and Experimental Reproductive Medicine
• /
• v.42 no.3
• /
• pp.111-117
• /
• 2015

Objective: In order to increase the number of mature oocytes usable for intracytoplasmic sperm injection (ICSI), we aimed to investigate the effect of co-culturing granulosa cells (GCs) on human oocyte maturation in vitro, the fertilization rate, and embryo development. Methods: A total of 133 immature oocytes were retrieved and were randomly divided into two groups; oocytes that were cultured with GCs (group A) and oocytes that were cultured without GCs (group B). After in vitro maturation, only oocytes that displayed metaphase II (MII) underwent the ICSI procedure. The maturation and fertilization rates were analyzed, as well as the frequency of embryo development. Results: The mean age of the patients, their basal levels of follicle-stimulating hormone, and the number of oocytes recovered from the patients were all comparable between the two study groups. The number of oocytes that reached MII (mature oocytes) was 59 out of 70 (84.28%) in group A, compared to 41 out of 63 (65.07%) in group B (p=0.011). No significant difference between fertilization rates was found between the two study groups (p=0.702). The embryo development rate was higher in group A (33/59, 75%) than in group B (12/41, 42.85%; p=0.006). The proportion of highest-quality embryos and the blastocyst formation rate were significantly lower in group B than in group A (p=0.003 and p<0.001, respectively). Conclusion: The findings of the current study demonstrate that culturing immature human oocytes with GCs prior to ICSI improves the maturation rate and the likelihood of embryo development.

• Journal of Embryo Transfer
• /
• v.27 no.3
• /
• pp.189-192
• /
• 2012

Although embryonic stem cells (ESCs) or ES-like cells are reported from many mammalian species other than the mouse, the culture system for murine ESCs may not be suitable to the other species. Previously many other research groups have modified either human or mouse ESC culture systems for bovine ESC culture. In this study, we compared three different culture mediums consisting of DMEM, ${\alpha}$-MEM or KnockOut$^{TM}$-DMEM (KO), which are modified from human or mouse ESC culture system, for the generation of bovine ESCs. In this study, some pre-requisite events which are important for establishment and long-term propagation of ESCs such as inner cell mass (ICM) attachment on feeder cells, primary colony formation and sustainability after passaging. Once the ICM clumps attached on feeder cells, this was designated as passage 0. In regards to the rate of ICM attachment, ${\alpha}$-MEM was superior to the other systems. For primary colony formation, there was no difference between DMEM and ${\alpha}$-MEM whereas KO showed lower formation rate than the other groups. For passaging, the colonies were split into 2~4 pieces and passed every 5~6 days. From passage 1 to passage 3, DMEM system seemed to be appropriate for maintaining putative bovine ESCs. On the other hand, ${\alpha}$-MEM tended to be more suitable after passage 6. Although ${\alpha}$-MEM support to maintain a ES-like cell progenies to passage 15, all three culture systems which are modified from human or mouse ESC culture media failed to retain the propagation and long-term culture of putative bovine ESCs. Our findings imply that more optimized alternative culture system is required for establishing bovine ESC lines.

• Clinical and Experimental Reproductive Medicine
• /
• v.49 no.4
• /
• pp.248-258
• /
• 2022

Objective: This research investigated the effects of human chorionic gonadotropin (HCG)-producing peripheral blood mononuclear cells (PBMCs) on the implantation rate and embryo attachment in mice. Methods: In this experimental study, a DNA fragment of the HCG gene was cloned into an expression vector, which was transfected into PBMCs. The concentration of the produced HCG was measured using enzyme-linked immunosorbent assay. Embryo attachment was investigated on the co-cultured endometrial cells and PBMCs in vitro. As an in vivo experiment, intrauterine administration of PBMCs was done in plaque-positive female mice. Studied mice were distributed into five groups: control, embryo implantation dysfunction (EID), EID with produced HCG, EID with PBMCs, and EID with HCG-producing PBMCs. Uterine horns were excised to characterize the number of implantation sites and pregnancy rate on day 7.5 post-coitum. During an implantation window, the mRNA expression of genes was evaluated using real-time polymerase chain reaction. Results: DNA fragments were cloned between the BamHI and EcoRI sites in the vector. About 465 pg/mL of HCG was produced in the transfected PBMCs. The attachment rate, pregnancy rate, and the number of implantation sites were substantially higher in the HCG-producing PBMCs group than in the other groups. Significantly elevated expression of the target genes was observed in the EID with HCG-producing PBMCs group. Conclusion: Alterations in gene expression following the intrauterine injection of HCG-producing PBMCs, could be considered a possible cause of increased embryo attachment rate, pregnancy rate, and the number of implantation sites.

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2000.05a
• /
• pp.64-75
• /
• 2000

During the last three decades considerable advances has been made in goat embryo production and transfer technology. The Korean native black goat is the most useful domestic ruminant in this country for biological investigation and application because it has a lot of merits such as relatively short generation period (1 vs 2 year for a cow), easy of handling, well adaptation, high fertility, convenient and inexpensive. This article covers the methods of superovulation, estrus synchronization, embryo collection and transfer techniques, pregnancy diagnosis and subsequent pregnancy and kidding rates for the production of transgenic Korean native black goats. More than one hundred goat kids have been produced as a result of our transgenic goat project via microinjection of foreign gene into pronuclei, in vitro culture, transfer of various stages of fresh and frozen-thawed microinjected embryos into oviducts or uteri of recipient does. We have got two transgenic goats carrying a transgene targeting the expression of recombinant human granulocyte colony stimulating factor (hG-CSF) to the mammary gland so far. Since collection and transfer of embryos in this species is usually accomplished by laparotomy, exteriorization of the reproductive tract for surgical embryo collection leads to the formation of post-operative adhesions. Nonsurgical or laparoscopic technique to reduce adhesions from repeated surgeries has great advantages in improving embryo production and transfer especially from valuable donors. We will discuss this later.

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2000.06a
• /
• pp.64-75
• /
• 2000

During the last three decades considerable advances has been made in goat embryo production and transfer technology. The Korean native black goat is the most useful domestic ruminant in this country for biological investigation and application because it has a lot of merits such as relatively short generation period(1 vs 2 year for a cow), easy of handling, well adaptation, high fertility, convenient and inexpensive. This article covers the methods of superovulation, estrus synchronization, embryo collection and transfer techniques, pregnancy diagnosis and subsequent pregnancy and kidding rates for the production of transgenic Korean native black goats. More than one hundred goat kids have been produced as a result of our transgenic goat project via microinjection of foreign gene into pronuclei, in vitro culture, transfer of various stages of fresh and frozen-thawed microinjected embryos into oviducts or uteri of recipient does. We have got two transgenic goats carrying a transgene targeting the expression of recombinant human granulocyte colony stimulating factor(hG-CSF) to the mammary gland so far. Since collection and transfer of embryos in this species is usually accomplished by laparotomy, exteriorization of the reproductive tract for surgical embryo collection leads to the formation of post-operative adhesions. Nonsurgical or laparoscopic technique to reduce adhesions from repeated surgeries has great advantages in improving embryo production and transfer especially from valuable donors. We will discuss this later.