scholarly journals 56 SOMATIC CELL NUCLEAR TRANSFER IN NON-HUMAN PRIMATES: THE POSSIBILITY OF USING OOCYTES MATURED IN VITRO FOR UP TO 3 DAYS AS HOST OOPLASTS

2005 ◽  
Vol 17 (2) ◽  
pp. 177
Author(s):  
N.T. Uoc ◽  
B.D. Bavister ◽  
N.V. Hanh ◽  
L.C. Bui ◽  
N.T. Thanh ◽  
...  

Production of cloned nonhuman primate embryos has been reported using mature oocytes obtained from donors treated in vivo with a high dose of recombinant human FSH (r-hFSH, 35 IU per day for 10 days). The disadvantages of this approach are the high cost of hormones and the need to use the oocytes shortly after collection. Our study aimed to investigate the possibility of using initial in vivo treatment with a reduced FSH dose followed by in vitro culture for long periods of up to 3 days to produce mature monkey oocytes as host ooplasts for somatic cell nuclear transfer (SCNT). Adult female long-tailed Macaque (Macaca fascicularis) monkeys were treated with r-hFSH (Serono, Aubonne, Switzerland, 35 IU per day, i.m.) either for 10 days with an injection of hCG (1000 IU, i/m) 34 h before oocyte collection (G.I) or with only r-hFSH for 7 days (G.II). Cumulus oocyte complexes (COCs) were collected by follicular aspiration and then cultured in TCM-199 medium (GIBCO) supplemented with estradiol-17β, FSH, LH, and 10% FCS at 39°C in an incubator with 5% CO2 in air. The maturation rate based on the level of cumulus expansion and the presence of the first polar body was recorded at the moment of collection and during 24 h, 48 h, and 72 h of in vitro maturation (IVM). For SCNT, the mature Metaphase II oocytes were separated from cumulus cells and selected for enucleation in the presence of cytochalasin B (Sigma, St. Louis, MO, USA). Skin fibroblasts obtained from adult monkeys were cultured in DMEM+ 10% FCS and induced to quiescence in DMEM 0% FCS 2 days before use. A single cell was transferred under the zona of each enucleated oocyte. Couplets were fused with two direct current (DC) pulses of 220 V/mm for 25 μs in Zimmerman medium. Fused oocytes were cultured in medium containing cyclohexamide for 6 h before placing them into monkey culture medium (Cook, Brisbane, Australia). The average number of oocytes collected per animal were 21.2 (n = 18) and 18.6 (n = 12) for the G.I and G.II treatments, respectively. For G.I, the rate of COCs with fully expanded cumulus was 42% at collection and was maximal (80%) at Day 1 of IVM. For G.II, fully expanded cumulus was not observed at the time of collection and during the first 2 days of IVM, but 75% of COCs had full cumulus expansion by Day 3 of IVM. The rates of intact and fused oocytes were 50.3% for G.I and 55.4% for G.II. From the fused oocytes, 67.8% and 64.4% developed to the 4- to 8-cell stages at Days 2–3 after nuclear transfer for G.I and G.II, respectively. From these data, it can be concluded that this approach can be applied to optimize production of mature oocytes for non-human primate SCNT and ART (assisted reproductive technologies) programs. This work was supported by AIRE-Development.

2008 ◽  
Vol 20 (1) ◽  
pp. 112 ◽  
Author(s):  
H. X. Wei ◽  
K. Zhang ◽  
Y. F. Ma ◽  
Y. Li ◽  
Q. Y. Li ◽  
...  

Accumulating evidence suggests that trichostatin A (TSA), a histone deacetylase inhibitor, can increase the success rate of somatic cloning. The objective of this study was to investigate the effect of 50 nm TSA treatment on the development of porcine somatic cell nuclear transfer (SCNT) and parthenogenically activated (PA) embryos. Cumulus-oocyte complexes were matured in vitro. The oocytes with the first polar body (PB1) were chosen for SCNT, and the rest with PB1 or good morphology were selected for PA by a single 100-μs direct current pulse of 1.6 kV cm–1, the same parameter as for electrical fusion. GFP transgenic fetal fibroblast cells were used as nuclear donors. Data were analyzed using SPSS (13.0; SPSS, Inc., Chicago, IL, USA) with one-way ANOVA. In Experiment 1, immediately after electrical fusion and activation, the reconstructed embryos were randomly cultured in porcine zygote medium 3 (PZM3) with 10 μg mL–1 cytochalasin B (CB) and 10 μg mL–1 cycloheximide (CHX), with either 0 nm (control) or 50 nm TSA for the first 4 h, before being cultured for another 20 h in PZM3 without CB and CHX. After being washed, the embryos were cultured in PZM3 medium without TSA until Day 6 at 39.0°C, 5% CO2, 5%O2, 90% N2, and 100% humidity. The same experimental design was used for PA embryos concurrently. The results showed that there were no significant differences in blastocyst rates for SCNT or PA between control and TSA groups (23.0 ± 6.1% v. 27.9 ± 6.3%; 21.0 ± 1.0% v. 17.5 ± 3.2%, respectively). Neither were there differences in the cell numbers of blastocysts (38.3 ± 5.7 v. 32.2 ± 3.4; 42.2 ± 3.5 v. 39.0 ± 1.9, respectively). In Experiment 2, TSA treatment was prolonged to either 36 or 40 h. The blastocyst rates of SCNT were increased (7.3 ± 1.2% (0 h), 13.3 ± 2.6% (36 h), and 20.0 ± 3.3% (40 h)), whereas those of PA were decreased (46.7 ± 5.0% (0 h), 27.7 ± 6.5% (36 h), and 30.8 ± 6.3% (40 h)). The cell numbers of blastocysts from either SCNT or PA were also decreased (SCNT: 47.5 ± 3.8, 37.5 ± 2.0, and 37.1 ± 3.3; PA: 46.1 ± 1.9, 37.5 ± 1.9, and 39.3 ± 2.2; P < 0.05). In Experiment 3, the cell number and the apoptotic index of Day 5, 6, and 7 PA blastocysts treated with 0 or 50 nm TSA were determined by the terminal deoxynucleotide-mediated nick end labeling (TUNEL) assay (Table 1). The results suggested that TSA treatment probably delayed embryo development, which may be one of the reasons for the lower cell numbers in the TSA-treated group. Table 1. Cell apoptosis of PA blastocyst by TUNEL


2006 ◽  
Vol 18 (2) ◽  
pp. 131
Author(s):  
K. Kaneyama ◽  
S. Kobayashi ◽  
S. Matoba ◽  
Y. Hashiyada ◽  
K. Imai ◽  
...  

Although many studies have been conducted on somatic cell nuclear transfer, there are only a few reports on cryopreservation of reconstructed embryos after nuclear transplantation. The objective of this study was to examine in vitro or in vivo development of vitrified blastocysts obtained by nuclear transfer. Nuclear transfer was carried out according to the procedure of Goto et al. (1999 Anim. Sci. J. 70, 243–245), and conducted using abattoir-derived oocytes and cumulus cells derived by ovum pickup from Holstein and Japanese Black cows. Embryos were vitrified as described by Saito et al. (1998 Cryobiol. Cryotech. 43, 34–39). The vitrification solution (GESX solution) was based on Dulbecco's PBS containing 20% glycerol (GL), 20% ethylene glycol (EG), 0.3 M sucrose (Suc), 0.3 M xylose (Xyl), and 3% polyethylene glycol (PEG). The blastocysts were equilibrated in three steps, with 10% GL, 0.1 M Suc, 0.1 M Xyl, and 1% PEG for 5 min (1); with 10% GL, 10% EG, 0.2 M Suc, 0.2 M Xyl, and 2% PEG for 5 min (2) and GESX solution (3). After transfer to GESX, equilibrated embryos were loaded to 0.25-mL straws and plunged into liquid nitrogen for 1 min. The vitrified blastocysts were warmed in water (20°C) and diluted in 0.5 M and 0.25 M sucrose for 5 min each. Equilibration and dilution procedures were conducted at room temperature (25–26°C). After dilution, the vitrified blastocysts were cultured in TCM-199 supplemented with 20% fetal calf serum and 0.1 mM β-mercaptoethanol at 38.5°C under gas phase of 5% CO2 in air. In Experiment 1, survival rates after vitrification were compared between the nuclear transfer and the IVF blastocysts. Survival rates of vitrified nuclear transfer blastocysts (n = 60, Day 8) at 24 and 48 h were 70.0% and 56.7%, respectively, and those of vitrified IVF blastocysts (n = 41) were 82.9% and 82.9%, respectively. There were no significant differences in survival rates at 24 and 48 h between the two groups. In Experiment 2, one (VIT-single) or two (VIT-double) vitrified and one (nonVIT-single) or two (nonVIT-double) nonvitrified reconstructed blastocysts per animal were transferred into Holstein dry cows. The result of Experiment 2 is shown in Table 1. This experiment demonstrated that the vitrification method in this study can be used for cloned embryo cryopreservation but the production rate should be improved. Table 1. Comparison of survival rates of vitrified or nonvitrified cloned embryos after transfer


2007 ◽  
Vol 19 (1) ◽  
pp. 147
Author(s):  
E. Lee ◽  
K. Song ◽  
Y. Jeong ◽  
S. Hyun

Generally, blastocyst (BL) formation and embryo cell number are used as main parameters to evaluate the viability and quality of in vitro-produced somatic cell nuclear transfer (SCNT) embryos. We investigated whether in vitro development of SCNT pig embryos correlates with in vivo viability after transfer to surrogates. For SCNT, cumulus–oocyte complexes (COCs) were matured in TCM-199 supplemented with follicular fluid, hormones, EGF, cysteine, and insulin for the first 22 h and in a hormone-free medium for 18 h. Three sources of pig skin cells were used as nuclear donor: (1) skin fibroblasts of a cloned piglet that were produced by SCNT of fetal fibroblasts from a Landrace × Yorkshire × Duroc F1 hybrid (LYD), (2) skin fibroblasts of a miniature pig having the human decay accelerating factor gene (hDAF-MP), and (3) skin fibroblasts of a miniature pig with a different strain (MP). MII oocytes were enucleated, subjected to nuclear transfer from a donor cell, electrically fused, and activated 1 h after fusion. SCNT embryos were cultured in a modified NCSU-23 (Park Y et al. 2005 Zygote 13, 269–275) for 6 days or surgically transferred (110–150 fused embryos) into the oviduct of a surrogate that showed standing estrus on the same day as SCNT. Embryos were examined for cleavage and BL formation on Days 2 and 6, respectively (Day 0 = the day of SCNT). BLs were examined for their cell number after staining with Hoechst 33342. Pregnancy was diagnosed by ultrasound 30 and 60 days after embryo transfer. Embryo cleavage was not affected by donor cells (82, 81, and 72% for LYD, hDAF-MP, and MP, respectively), but BL formation was higher (P &lt; 0.05) in hDAF-MP (16%) than in LYD (9%) and MP (6%). MP showed higher (P &lt; 0.05) BL cell number (46 cells/BL) than hDAF-MP (34 cells) but did not show a difference from LYD (37 cells). LYD and MP showed higher pregnancy rates (Table 1) on Days 30 and 60, even though they showed lower BL formation in vitro. Due to a relatively small number of embryo transfers through a limited period, we could not exclude any possible effects by seasonal or operational differences. These results indicated that pregnancy did not correlate with in vitro BL formation of SCNT pig embryos but rather were affected by the source of donor cells. Table 1.In vivo development of somatic cell nuclear transfer pig embryos derived from different sources of donor cells This work was supported by the Research Project on the Production of Bio-organs (No. 200506020601), Ministry of Agriculture and Forestry, Republic of Korea.


Reproduction ◽  
2005 ◽  
Vol 130 (5) ◽  
pp. 681-694 ◽  
Author(s):  
P Tveden-Nyborg ◽  
T T Peura ◽  
K M Hartwich ◽  
S K Walker ◽  
P Maddox-Hyttel

The processes of cellular differentiation were studied in somatic cell nuclear transfer (SCNT), in vitro cultured (IVC) and in vivo developed (in vivo) ovine embryos on days 7, 9, 11, 13, 17 and 19. SCNT embryos were constructed from in vitro matured oocytes and granulosa cells, and IVC embryos were produced by in vitro culture of in vivo fertilized zygotes. Most SCNT and IVC embryos were transferred to recipients on day 6 while some remained in culture for day 7 processing. In vivo embryos were collected as zygotes, transferred to intermediate recipients and retransferred to final recipients on day 6. All embryos were processed for examination by light and transmission electron microscopy or immunohistochemical labelling for alpha-1-fetoprotein and vimentin. Overall, morphological development of in vivo embryos was superior to IVC and SCNT embryos. Day 7 and particularly day 9 IVC and SCNT embryos had impaired hypoblast development, some lacking identifiable inner cell masses. On day 11, only in vivo and IVC embryos had developed an embryonic disc, and gastrulation was evident in half of in vivo embryos and one IVC embryo. By day 13, all in vivo embryos had completed gastrulation whereas IVC and SCNT embryos remained retarded. On days 17 and 19, in vivo embryos had significantly more somites and a more developed allantois than IVC and SCNT embryos. We conclude that IVC and particularly SCNT procedures cause a retardation of embryo development and cell differentiation at days 7–19 of gestation.


Zygote ◽  
2008 ◽  
Vol 16 (3) ◽  
pp. 211-222 ◽  
Author(s):  
Wakayama Sayaka ◽  
Kishigami Satoshi ◽  
Nguyen Van Thuan ◽  
Ohta Hiroshi ◽  
Hikichi Takafusa ◽  
...  

SummaryAnimal cloning methods are now well described and are becoming routine. Yet, the frequency at which live cloned offspring are produced remains below 5%, irrespective of the nuclear donor species or cell type. One possible explanation is that the reprogramming factor(s) of each oocyte is insufficient or not properly adapted for the receipt of a somatic cell nucleus, because it is naturally prepared only for the receipt of a gamete. Here, we have increased the oocyte volume by oocyte fusion and examined its subsequent development. We constructed oocytes with volumes two to nine times greater than the normal volume by the electrofusion or mechanical fusion of intact and enucleated oocytes. We examined their in vitro and in vivo developmental potential after parthenogenetic activation, intracytoplasmic sperm injection (ICSI) and somatic cell nuclear transfer (SCNT). When the fused oocytes were activated parthenogenetically, most developed to morulae or blastocysts, regardless of their original size. Diploid fused oocytes were fertilized by ICSI and developed normally and after embryo transfer, we obtained 12 (4–15%) healthy and fertile offspring. However, enucleated fused oocytes could not support the development of mice cloned by SCNT. These results suggest that double fused oocytes have normal potential for development after fertilization, but oocytes with extra cytoplasm do not have enhanced reprogramming potential.


2014 ◽  
Vol 26 (1) ◽  
pp. 128
Author(s):  
C. P. Buemo ◽  
A. Gambini ◽  
I. Hiriart ◽  
D. Salamone

Somatic cell nuclear transfer (SCNT) derived blastocysts have lower cell number than IVF-derived blastocysts and their in vivo counterparts. The aim of this study was to improve the blastocyst rates and quality of SCNT blastocysts by the aggregation of genetically identical free zona pellucida (ZP) porcine clones. Cumulus–oocyte complexes were recovered from slaughterhouse ovaries by follicular aspiration. Maturation was performed in TCM for 42 to 48 h at 39°C and 5% CO2. After denudation by treatment with hyaluronidase, mature oocytes were stripped of the ZP using a protease and then enucleated by micromanipulation; staining was performed with Hoechst 33342 to observe metaphase II. Ooplasms were placed in phytohemagglutinin to permit different membranes to adhere between each other; the ooplasm membrane was adhered to a porcine fetal fibroblast from an in vitro culture. Adhered membranes of the donor cell nucleus and enucleated oocyte cytoplasm were electrofused through the use of an electric pulse (80 V for 30 μs). All reconstituted embryos (RE) were electrically activated using an electroporator in activation medium (0.3 M mannitol, 1.0 mM CaCl2, 0.1 mM MgCl2, and 0.01% PVA) by a DC pulse of 1.2 kV cm–1 for 80 μs. Then, the oocytes were incubated in 2 mM 6-DMAP for 3 h. In vitro culture of free ZP embryos was achieved in a system of well of wells in 100 μL of medium, placing 3 activated oocytes per microwell (aggregation embryo), whereas the control group was cultivated with equal drops without microwells. Embryos were cultivated at 39°C in 5% O2, 5% CO2 for 7 days in SOF medium with a supplement of 10% fetal bovine serum on the fifth day. The RE were placed in microwells. Two experimental groups were used, control group (not added 1X) and 3 RE per microwell (3X). At Day 7, resulting blastocysts were classified according to their morphology and diameter to determine their quality and evaluate if the embryo aggregation improves it. Results demonstrated that aggregation improves in vitro embryo development rates until blastocyst stage and indicated that blastocysts rates calculated over total number of oocytes do not differ between groups (Table 1). Embryo aggregation improves cleavage per oocyte and cleavage per microwell rates, presenting statistical significant differences and increasing the probabilities of higher embryo development generation until the blastocyst stage with better quality and higher diameter. Table 1.Somatic cell nuclear transfer cloning and embryo aggregation


Zygote ◽  
2008 ◽  
Vol 16 (2) ◽  
pp. 153-159 ◽  
Author(s):  
Satoshi Sugimura ◽  
Manabu Kawahara ◽  
Takuya Wakai ◽  
Ken-ichi Yamanaka ◽  
Hiroshi Sasada ◽  
...  

SummaryIn many animals, cytochalasins have generally been used as cytoskeletal inhibitors for the diploid complement retention of somatic cell nuclear transfer (SCNT) embryos. However, limited information is available on the effects of cytochalasins on the in vitro development of SCNT embryos. Hence, we compared the effects of cytochalasin B (CB) and cytochalasin D (CD) on pseudo-polar body (pPB) extrusion, cortical actin filament (F-actin) distribution in porcine parthenogenetic oocytes and in vitro development of SCNT embryos that were reconstructed using foetal fibroblasts in the G0/G1 phase derived from miniature pigs. CB (7.5 μg/ml) and CD (2.5 μg/ml) treatments effectively inhibited pPB extrusion in SCNT embryos. CB (2.5 μg/ml) treatment could not inhibit pPB extrusion and insufficiently destabilized F-actin immediately following artificial activation. In parthenogenetic oocytes treated with 2.5 μg/ml CD, normal reorganization and uniform distribution of cortical F-actin at the cytoplasmic membrane were observed at 8 h after artificial activation; this finding was similar to that of control oocytes. In contrast, parthenogenetic oocytes treated with 7.5 μg/ml CB showed non-uniform distribution of F-actin at 8 h after artificial activation. On day 5 after in vitro cultivation, the blastocyst formation rate of SCNT embryos treated with 2.5 μg/ml CD was significantly higher than that of SCNT embryos treated with 2.5 and 7.5 μg/ml CB (p < 0.05). Hence, the present findings suggest that CD is more effective than CB as the cytoskeletal inhibitor for the production of SCNT embryos in miniature pigs.


2011 ◽  
Vol 411 (2) ◽  
pp. 397-401 ◽  
Author(s):  
Yongye Huang ◽  
Xiaochun Tang ◽  
Wanhua Xie ◽  
Yan Zhou ◽  
Dong Li ◽  
...  

2016 ◽  
Vol 28 (11) ◽  
pp. 1762 ◽  
Author(s):  
Daehwan Kim ◽  
Sangkyu Park ◽  
Yeon-Gil Jung ◽  
Sangho Roh

We established and maintained somatic cell nuclear transfer embryo-derived stem-like cells (SCNT-eSLCs) from the traditional Korean beef cattle species, HanWoo (Bos taurus coreanae). Each SCNT blastocyst was placed individually on a feeder layer with culture medium containing three inhibitors of differentiation (3i). Primary colonies formed after 2–3 days of culture and the intact colonies were passaged every 5–6 days. The cells in each colony showed embryonic stem cell-like morphologies with a distinct boundary and were positive to alkaline phosphatase staining. Immunofluorescence and reverse transcription–polymerase chain reaction analyses also confirmed that these colonies expressed pluripotent markers. The colonies were maintained over 50 passages for more than 270 days. The cells showed normal karyotypes consisting of 60 chromosomes at Passage 50. Embryoid bodies were formed by suspension culture to analyse in vitro differentiation capability. Marker genes representing the differentiation into three germ layers were expressed. Typical embryonal carcinoma was generated after injecting cells under the testis capsule of nude mice, suggesting that the cultured cells may also have the potential of in vivo differentiation. In conclusion, we generated eSLCs from SCNT bovine embryos, using a 3i system that sustained stemness, normal karyotype and pluripotency, which was confirmed by in vitro and in vivo differentiation.


Sign in / Sign up

Export Citation Format

Share Document