• BMB Reports
• /
• 제34권3호
• /
• pp.206-211
• /
• 2001

Endostatin, a proteolytic fragment of collagen XVIII, is a potent inhibitor of angiogenesis and the growth of several primary tumors. However, the opinions on the activity of endostatin derivatives deleted N- or C- terminal are still controversial. In this regard, we produced mouse endostatin and its derivatives in the prokaryotic system, and studied their anti-tumor activity. The [$^3H$]-thymidine incorporation assay demonstrated that N-terminal deleted mouse endostatin, and a C- and N-terminal deleted mutant, effectively inhibited the proliferation of human umbilical vein endothelial cells (HUVECs). The biological activity of endostatin was also shown by its in vivo anti-angiogenic ability on the chorioallantoic membrane (CAM) of a chick embryo. Treatment of $200\;{\mu}g$ of mouse endostatin, or N-terminal deleted mouse endostatin, inhibited capillary formation of CAM 45 to 71%, which is comparative to a 80% effect of positive control, $1\;{\mu}g$ of retinoic acid. An in vivo mouse tumor growth assay showed that N-terminal deleted mouse endostatin, and the N-/C-terminal deleted mutant, significantly repressed the growth of B16F10 melanoma cells in mice as did the full-length mouse endostatin. According to these results, N-and N-/C-terminal deleted mouse endostatins are the potent inhibitors of tumor growth and angiogenesis.

• 대한수의학회지
• /
• 제30권2호
• /
• pp.123-127
• /
• 1990

모성 및 부성 genome의 기능을 알아보기 위하여 미세조작기법과 Sendai virus를 이용한 핵융합 기술을 이용하여 2개의 자성전핵만으로 구성된 2배체의 gynogenetic 수정란을 그리고 2개의 웅성전핵만으로 구성된 2배체의 androgenetic 수정란을 인위적으로 작출하였다. 이들의 작출효율은 biparental 수정란에서는 56%, gynogenetic 수정란에서는 50% 그리고 androgenetic 수정란에서는 56% 이었다. 이들을 체외에서 배양한 결과 gynogenetic 및 androgenetic 수정란은 2-세포기 이후에는 biparental 및 intact 수정란에 비하여 그 발달능이 매우 저조하였으나 이들 중 25% 이상이 포배까지 발달한 수 있음을 확인하였다. Gynogenetic 및 androgenetic 수정란을 동기화된 수란생쥐의 난관내에 이식하였던 바, androgenetic 수정란은 전혀 착상 되지 않았으나, gynogenetic 수정란에서는 착상이 확인되었다. 핵이식기법으로 인위조작된 2배체의 biparental 수정란으로부터 28마리의 생쥐 신생자를 생산하였다.

• 한국수정란이식학회지
• /
• 제19권2호
• /
• pp.133-145
• /
• 2004

난자의 체외성숙 및 체외배양에는 일반적으로 동물의 혈청을 사용하고 있다. 그러나, 채취한 소의 상태에 따라서 혈청의 질에 차이가 있어 실험데이터가 일정하지 않을 수 있고, 그것으로부터 바이러스, 세균, 마이코플라즈마 등에 오염될 가능성이 있다. 따라서, 본 실험에서는 완전 무 혈청 배양액에서 난자의 성숙, 배 발생율, 세포 수, 동결성을 검토하였다. 다음으로, 근래 혈청배지로 생산한 체외 배양 수정란은 과체중의 산자 생산, 초기 산자 사망률, caesarean section, dystocia 같은 발병으로 문제가 지적되고 있다. 그러나 무 혈청 배지로 생산한 체외 배양 수정란은 이러한 현상을 개선할 수 있다는 보고가 있어 본 실험에서는 완전 무혈청 배양액에서 생산된 동결란과 신선란을 젖소에 이식하여 그 결과를 검토하였다. 무혈청 배양액에는 에너지원과 세포성장인자가 첨가된 IVD101과 IVMD101, 대조군인 혈청 배양액에는 TCM199 + 10% FBS가 사용되었다. IVMD101에 의해 체외성숙이 이루어 졌고, 혈청이 첨가된 TCM199 + 10% FBS에서는 12.4% 배 발생율을 보인데 반해, 무혈청 배양액 IVD101과 IVMD101이 각 32.4%, 34.5%로 훨씬 높은 배 발생율을 보였다. 더욱이, 세포 수에 있어서도 무혈청 배양액에서 발생된 배반포의 세포수가 혈청이 첨가된 배양액에서 발생된 배반포의 세포수보다 월등하였으며, 이는 체내란과 비슷한 세포 수를 보이고 있다. 수정란의 내동성을 보면, 융해하고 24시간 배양기 정치 후에 IVD101과 IVMD101은 94.5%, 95.8%의 생존율을 보인 반면 TCM199 + 10% FBS는 52.5%에 불과하다. 융해하고 72시간후 탈출 배반포율이 IVD101과 IVMD101는 78.4%, 83.7%였는데 반해 TCM199 + 10% FBS는 32.0%였다. 마지막으로, 무혈청 배양액에서 발생한 동결란과 신선란을 젖소에 이식한 후에 임신율에 있어서는 유의적 차이는 없었지만, 무혈청 배지에서 생산된 수정란의 내동성의 탁월함이 증명되었다. 이러한 결과들로 종합해 보면, 무혈청 배양액 (IVD101, IVMD101)에서 발생된 수정란이 혈청 배양액에서 발생된 수정란보다 배발생율, 세포수, 동결성, 임신율에 있어서 우수함을 알 수 있었다. 이러한 무혈청 배양액은 배발생 과정의 연구뿐만 아니라 수정란 이식을 위한 고품질의 체외 수정란의 대량 생산, 복제, 형질전환 동물 생산 등에도 유익할 것으로 사료된다.

• Clinical and Experimental Reproductive Medicine
• /
• 제23권1호
• /
• pp.103-108
• /
• 1996

Through the previous studies(I,II), it was observed that human follicular fluid(HFF) was more effective than human fetal cord serum(HFCS) on promoting meiotic resumption of oocytes and improving embryonic development of mouse in vitro. On the basis of these results, we have gradually exchanged HFCS with HFF as protein supplement in human ART. This study was performed to investigate the efficiency of HFF on improving the pregnancy rate in ART. Oocytes were retrieved transvaginally from patients treated with pituitary suppression with GnRH-agonist and ovarian stimulation with human menopausal gonadotro-pin(HMG) and pure follicle stimulating hormone(FSH). Aspirated oocytes were rinsed and cultured in TCM-199 containing HFF, and the concentrations of HFF were adjusted to 10, 20, and 30% according to the use for insemination, embryo growth and embryo transfer, respectively. As possible as, we tried to do embryo transfer into fallopian tube to mimic the coincidence of the cell stage with the place of sojourn in vivo, so we performed various ART programs(IVF & ET; in vitro fertilization, ZIFT; zygote intra fallopian-tube transfer, ZIFT & ET) according to the tubal conditions of patients. On the while, intra cytoplasmic sperm injection(ICSI) was used to assist IVF of the patients who had shown poor standard IVF results by immunological or severe male factor. Of the 255 cycles of ART programs using HFF as protein supplement, 118 cycles were turn out to be succeeded in pregnancy(46.2%, per cycle, p<0.05), while 21 pregnancies were achieved in the 69 cycles using HFCS(30.4%). The 255 cycles using HFF were subdivided into cycles with the type of ART programs, and each pregnancy rate of the ART programs were 44.7% (IVF & ET, 76/170 cycles), 53.4%(ZIFT, 31/58 cycles) and 40.7% (ZIFT & ET, 11/27 cycles), respectively. In the 61 ICSI cycles using HFF, 28 cycles succeed in pregnancy(45.9%), while 7 pregnancies were obtained in the 17 ICSI cycles using HFCS. Also the ongoing pregnancy rate in the group using HFF(78.8%, 93/118 cycles) was higher than that in the group using HFCS(61.9%). Therefore, we found that the use of HFF as protein supplement was more suitable and effective than the use of HFCS to improve the pregnancy rate in ART.

• 한국수정란이식학회지
• /
• 제12권3호
• /
• pp.229-246
• /
• 1997

Implantation is a most important biological process during pregnancy whereby conceptus establishes its survival as well as maintenance of pregnancy. During the periimplantation period, both uterine endometriurn and conceptus synthesize and secrete a host of growth factors and cytokines which mediate the actions of estrogen and /or progesterone and also exert their steroid-independent actions. Growth factors expressed by the materno-conceptal unit en masse have important roles in cell migration, stimulation or inhibition of cell proliferation, cellular differentiation, maintenance of pregnancy and materno-conceptal communications in an autorcrine /paracrine manner. The present review focuses on the role of the intrauterine IGF system during periimplantation conceptus development. The IGF system comprises of IGF- I and IGF- II ligands, types I and II IGF receptors and six or more IGF-binding proteins(IGFBPs). IGFs and IGFBPs are expressed and secreted by uterine endometrium with tissue, pregnancy stage and species specificities under the influence of estrogen, progesterone and other growth factor(s). Conceptus also synthesizes components of the IGF system beginning from a period between 2-cell and blastocyst stages. Maternal IGFs are utilized by both maternal and conceptal tissues; conceptus-derived growth factors are believed to be taken up primarily by conceptus. IGFs enhance the development of both maternal and conceptal compartments in a wide range of biological processes. They stimulate proliferation and differentiation of endometrial cells and placental precursor cells including decidual transformation from stromal cells, placental formation and the synthesis of some steroid and protein hormones by differentiated endometrial cells or placenta. It is also well-documented in a number of experimental settings that both IGFs stimulate preimplantation embryo development. In slight contrast to these, prenatal mice carrying a null mutation of IGF and /or IGF receptor gene do not exhibit any apparent growth retardation until after implantation. Reason (s) for this discrepancy between the knock-out result and the in vitro ones, however, is not known. IGFBPs, in general, are believed to inhibit IGF action within the materno-conceptal unit, thereby allowing endometrial stromal cell differentiation as well as dampening ex cessive placental invasion into maternal tissue. There is evidence, however, indicating that IGFBP can enhance IGF action depending on environrnental conditions perhaps by directioning IGF ligand to the target cell. There is also a third possibility that certain IGFBPs and their proteolytic fragments may have their own biological activities independent of the IGF. In addition to IGFBPs, IGFBP proteases including those found within the uterine tissue or lumen are thought to enhance IGF bioavailability by degrading their substrates without affecting their bound ligand. In this regard, preliminary results in early pregnant pigs suggest that a partially characterized IGFBP protease activity in uterine luminal fluid enhances intrauterine IGF bioavailability during conceptus morphological development. In summary, a number of in vitro results indicate that IGFs stimulates the development of the rnaterno-conceptal unit during the periimplantation period. IGFBPs appear to inhibit IGF action by sequestering their ligands, whereas IGFBP proteases are thought to enhance intrauterine bioavailability of IGFs. Much is remaining to be clarified, however, regarding the roles of the individual IGF system components. These include in vivo evidence for the role of IGFs in early conceptus development, identification of IGF-regulated genes and their functions, specific roles for individual IGFBPs, identification and characterization of IGFBP proteases. The intrauterine IGF club house thus will be paying a lot of attention to forthcoming results in above and other areas, with its door wide-open!

• 한국수정란이식학회지
• /
• 제23권2호
• /
• pp.101-108
• /
• 2008

This study investigated the developmental ability and gene expression of somatic cell nuclear transfer embryos using ear skin fibroblast cells derived from miniature pig. When miniature pig (m) and landrace pig (p) were used as donor cells, there were no differences in cleavage (79.2 vs. 78.2%) and blastocyst rates (27.4 vs. 29.7%). However, mNT blastocysts showed significantly higher apoptosis rate than that of pNT blastocysts (6.1 vs. 1.7%) (p<0.05). The number of nuclei in pNT blastosysts was significantly higher than that of mNT (35.8 vs. 29.3) (p<0.05). Blastocysts were analyzed using Realtime RT-PCR to determine the expression of Bax-${\alpha}$, Bcl-xl, H19, IGF2, IGF2r and Xist. Bax-${\alpha}$ was higher in mNT blastocyst than pNT blastocyst (p<0.05). There was no difference in Bcl-xl between two NT groups. Bax-${\alpha}$/Bcl-xl was, however, significantly higher in mNT blastocyst compared to pNT. The expression of imprinting genes were aberrant in blastocysts derived from NT compared to in vivo blastocysts. H19 and IGF2r were significantly lower in mNT blastocysts (p<0.05). The expression of IGF2 and Xist was similar in two NT groups. However, imprinting genes were expressed aberrantly in mNT compared to pNT blastocysts. The present results suggest that the NT between donor cells derived from miniature pig and recipient oocytes derived from crossbred pig might affect reprogramming of donor cell, resulting in high apoptosis and aberrant expression patterns of imprinting genes.

• 한국수정란이식학회지
• /
• 제21권3호
• /
• pp.225-231
• /
• 2006

본 연구는 제주도의 흑우에서 다배란을 유기한 후 발정기 동안 혈중 호르몬의 농도 검사, 혈액 생화학 검사, 체내 수정란 회수율 등을 관찰하였다. FSH를 4일간 8회 50 mg씩 주사하여 다배란을 유기하였다. 성호르몬의 측정은 radioimmunoassay (RIA)법으로 측정하였으며 혈액 생화학치는 자동혈청 분석기로 측정하였다. 인공 수정 후 7일에 수정란을 비외과적 방법으로 회수하였다. 본 연구의 결과는 다음과 같았다. 1. 혈중 호르몬의 농도를 측정한 결과 progesterone농도는 day -11에 $7.2{\pm}3.8ng/ml$ 이었으며 day -2에 급격히 감소하여 day 0에는 $0.2{\pm}0.1ng/ml$로 최저치를 유지하다가 day 2 후 상승하였다. Estradiol의 농도는 day -11에 $10.6{\pm}4.3pg/ml$였으며 day 0에는 $15.0{\pm}2.1pg/ml$ 로 최고치를 기록했다. 2. 다배란처리 후 발정 주기 동안의 AST, ALT, BUN, creatine, cholesterol, albumin 및 total protein등 혈액 생화학치의 변화를 측정한 결과 각 혈액 생화학치의 변화는 정상 소의 정상 범위 내 있었으며 유의적 차이는 없었다. 3. 공란우 12두에서 총 62개의 수정란을 회수하였다. 이중 이식 가능한 수정란은 37개(59.7%)였다. 본 연구의 결과로 제주흑우에서 다배란을 유도한 후 발정기 중 호르몬과 혈액생화학치의 변화양상을 알 수 있었다.

• Molecules and Cells
• /
• 제37권1호
• /
• pp.59-65
• /
• 2014

Eph receptors and their ligands ephrins have been implicated in guiding the directed migration of neural crest cells (NCCs). In this study, we found that Wnt1-Cre-mediated expression of ephrinA5-Fc along the dorsal midline of the dien- and mesencephalon resulted in severe craniofacial malformation of mouse embryo. Interestingly, expression of cephalic NCC markers decreased significantly in the frontonasal process and branchial arches 1 and 2, which are target areas for the migratory cephalic NCCs originating in the dien- and mesencephalon. In addition, these craniofacial tissues were much smaller in mutant embryos expressing ephrinA5-Fc. Importantly, EphA7-positive cephalic NCCs were absent along the dorsal dien- and mesencephalon of mutant embryos expressing ephrinA5-Fc, suggesting that the generation of cephalic NCCs is disrupted due to ephrinA5-Fc expression. NCC explant experiments suggested that ephrinA5-Fc perturbed survival of cephalic NCC precursors in the dorsal midline tissue rather than affecting their migratory capacity, which was consistent with our previous report that expression of ephrinA5-Fc in the dorsal midline is responsible for severe neuroepithelial cell apoptotic death. Taken together, our findings strongly suggest that expression of ephrinA5-Fc decreases a population of cephalic NCC precursors in the dorsal midline of the dien- and mesencephalon, thereby disrupting craniofacial development in the mouse embryos.

• 한국가축번식학회지
• /
• 제18권1호
• /
• pp.7-13
• /
• 1994

To verify in vivo viability of IVF-derived bovine embryos, morula and blastocysts that developed from in vitro matured and fertilized ova were transferred to the uteri of recipient cows and normal calves were produced. To produce IVF-derived bovine morula or blastocysts, ova matured and fertilized in vitro were cultured in culture medium for 7~8 days at 39$^{\circ}C$ under the humicified atmosphere of 5% CO2. Two different culture systems, a co-culture system with TCM-199 and bovine epithelial cells (BOEC) and CR1aa without somatic cell support, were compared. Cleavage rates to 2~8 cell stage and developmental rates of IVF-derived bovine embryos to blastocyst stage were not different between co-culture system (51.3 and 14.0%) and CR1aa medium (60.4 and 22.1%), respectively. Embryos were classified into three grades by embryo quality and then one or two embryos in higher quality(A and B grades) were transferred to the uterus of recipients. In this study Korean Native calf was first born after transfer of IVF-derived embryos. Total four live calves were normally developed to term from IVF-derived bovine blastocysts and one female fetus was still-born approximatedly 8 months of gestation, but there was no pregnancy after transfer of morula. Therefore, normal calves could be produced after transfer of IVF-derived bovine embryos cultured in CR1aa medium without somatic cell support. In addition, our results suggest that in transfer of IVF-derived bovine embryos blastocyst stage is better than morula.

• 대한수의학회지
• /
• 제38권1호
• /
• pp.209-216
• /
• 1998

The purpose of present study is to improve the efficiency of fusion and the developmental rates of nuclear transplanted embryos to produce genetically identical twins from Korean native cattle. The diameter of aspirated follicles had no significant effect on the recovery rates of oocytes collected by ovum pick-up technique. The fusion rates of nuclear transplanted embryos were significantly higher in 50 and $100{\mu}s$ DC duration groups(73.3 and 72.0% ; respectively) than that in $30{\mu}s$ group(55.6% ; p<0.05). The cleavage rates of nuclear transplanted embryos appeared to be significantly higher in donor nuclei derived from in vivo (65.0%) than in those from in vitro (50.5% ; p<0.01), but the developmental rates to morulae and blastocysts were not significantly different between them(13.7 vs 10.9%, respectively).