49 INTRA-GENUS CLONED EMBRYOS PRODUCTION AND PREGNANCIES DERIVED FROM LEOPARD CAT NUCLEI AND DOMESTIC CAT ENUCLEATED EGGS

2006 ◽  
Vol 18 (2) ◽  
pp. 133 ◽  
Author(s):  
I. K. Kong ◽  
H. S. Lee ◽  
N. H. Kim ◽  
L. H. Kim ◽  
H. D. Shin ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Nuclear Genome ◽  
Fibroblast Cell ◽  
Domestic Cat ◽  
Developmental Competence ◽  
Cell Nuclei ◽  
Reconstructed Embryos ◽  
Significant Difference ◽  
Leopard Cat

The leopard cat (Prionailurus bengalensis), a member of the felidae family, is currently listed as threatened by the Ministry of Environment in South Korea. In exotic or endangered species, the lack of oocytes and recipients precludes the use of traditional somatic cell nuclear transfer (NT), and an approach such as intragenus NT may be the only alternative for producing embryos and offspring. In the present study, we used the leopard cat (LC) as a somatic cell donor to evaluate the in vivo developmental competence, after transfer into domestic cat recipients, of cloned embryos produced by the fusion of LC fibroblast cell nuclei with domestic cat cytoplasts. A total of 412 enucleated domestic cat oocytes were reconstructed with either male (Treatment A) or female (Treatment B) adult LC fibroblasts. There was no significant difference in fusion rate (60.4 vs. 56.9%) between Treatment A and B. Of the fused couplets, the cleavage and blastocyst developmental rate in Treatment A were greater than those in Treatment B (69.5 vs. 60.9%; 8.3 vs. 7.8%; P < 0.05). In treatment A, in vivo developmental studies at 30-45 days postimplantation demonstrated 4.8% (21/435) of reconstructed embryos (n = 435) had entered into the uterine lining of recipients, but only 1.4% (6/435) formed fetuses. However, all of the reconstructed embryos failed to develop to term (65 days). Microsatellite analyses confirmed that the nuclear genome of the cloned fetuses were LC in origin.

scholarly journals 38BIRTH OF AFRICAN WILD CAT CLONED KITTENS

2004 ◽  
Vol 16 (2) ◽  
pp. 141 ◽  
Author(s):  
M.C. Gomez ◽  
C.E. Pope ◽  
A.M. Giraldo ◽  
L. Lyons ◽  
R.F. Harris ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Nuclear Transfer ◽  
Pcr Amplification ◽  
Domestic Cat ◽  
Developmental Competence ◽  
Felis Silvestris ◽  
Cell Nuclei ◽  
Oocyte Aspiration

The African wild cat (AWC, Felis silvestris lybica; 2n=38) is one of the smallest wildcats, and it’s future is threatened by hybridization with domestic cats (Felis silvestris catus; 2n=38). Nuclear transfer (NT) is a potentially valuable tool for retaining genetic variability, and could assist in the continuation of species with few remaining individuals. Inter-species nuclear transfer into domestic cat (DSH) supports development of somatic cell nuclei from AWC (Gomez et al., 2003, Biol Reprod 69, 1032–1041). Therefore, the purpose of the present study was to evaluate the in vivo developmental competence of nuclear transfer embryos derived by fusion of African wildcat fibroblasts with domestic cat cytoplasts, after transfer into domestic cat recipients. In vivo- and in vitro-matured domestic cat oocytes were mechanically enucleated in modified Tyrodes salt solution supplemented with 20μgmL−1 of cytochalasin B (CCB) and 2mgmL−1 of sucrose, and reconstructed with AWC fibroblast cells derived from an adult male; cultured and passaged 1 to 3 times before serum-starved with DMEM +0.5% FBS and cultured for 5 additional days before use. Fusion took place in fusion medium (0.3M mannitol and 0.1mMMg+2), and membrane fusion was induced by applying a 3s AC pre-pulse of 20V, 1MHz; followed by two 30μs DC pulses of 240V/mm at intervals of 0.5s. Fused couplets were activated 2–3h after fusion by placing the couplets between two electrodes in a fusion chamber containing 3mL of fusion medium and exposing them to two 60μs DC pulses of 120V/mm. Then, couplets were incubated in 30μL drops of Tyrodes solution containing 1% MEM nonessential amino acids, 3mgmL−1 BSA (IVC-1 medium), and supplemented with 10μgmL−1 cycloheximide and 5μgmL−1 CCB at 38°C in 5% CO2 for 4h. After activation, cloned embryos were cultured in 500μL of IVC-1 medium until the day of the transfer. Derived AWC NT embryos were transferred into the oviducts (Day 1) or uteri (Days 5, 6, 7) of 36 gonadotrophin-treated DSH recipients on Day 1 after ovulation or on Days 5, 6, or 7 after oocyte aspiration, respectively. Pregnancy was assessed by ultrasonography on Days 21 to 23. One domestic cat was still pregnant and ongoing on Day 60. Kittens were delivered by Cesarean section in each of the seven pregnant recipients on days 61 to 67 of gestation. The kittens weighed an average of 86.2g (50.0 to 103g) and died within 36h after delivery. The post-mortem pathology reports revealed that most of them had an immature respiratory system. The clonal status of the kittens was assessed by multiplex PCR amplification of 20 microsatellite markers, including seven markers that are known to be on the X chromosome. Results from these assays confirmed that the AWC kittens had originated from the AWC donor somatic cell line and were not related to the DSH recipient cats. In summary, these results indicate that AWC cloned kittens can be produced by ET of embryos derived from AWC cells into DSH cytoplasts. Research was funded partially by the John &amp; Shirley Davies Foundation. Table 1

24 BUFFALO (BUBALUS BUBALIS) SOMATIC CELL NUCLEAR TRANSFER EMBRYOS PRODUCED FROM FROZEN–THAWED SEMEN-DERIVED SOMATIC CELLS: EFFECT OF TRICHOSTATIN A ON THE IN VITRO AND IN VIVO DEVELOPMENTAL POTENTIAL, QUALITY, AND EPIGENETIC STATUS

2015 ◽  
Vol 27 (1) ◽  
pp. 104
Author(s):  
N. L. Selokar ◽  
M. Saini ◽  
H. Agrawal ◽  
P. Palta ◽  
M. S. Chauhan ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Trichostatin A ◽  
Somatic Cells ◽  
Developmental Potential ◽  
Reconstructed Embryos ◽  
Frozen Semen ◽  
Significant Difference

Cryopreservation of semen allows preservation of somatic cells, which can be used for the production of progeny through somatic cell nuclear transfer (SCNT). This approach could enable restoration of valuable high-genetic-merit progeny-tested bulls, which may be dead but the cryopreserved semen is available. We have successfully produced a live buffalo calf by SCNT using somatic cells isolated from >10 year old frozen semen (Selokar et al. 2014 PLoS One 9, e90755). However, the calf survived only for 12 h, which indicates faulty reprogramming of these cells. The present study was, therefore, carried out to study the effect of treatment with trichostatin A (TSA), an epigenetic modifier, on reprogramming of these cells. Production of cloned embryos and determination of quality and level of epigenetic markers in blastocysts were performed according to the methods described previously (Selokar et al. 2014 PLoS One 9, e90755). To examine the effects of TSA (0, 50, and 75 nM), 10 separate experiments were performed on 125, 175, and 207 reconstructed embryos, respectively. The percentage data were analysed using SYSTAT 12.0 (SPSS Inc., Chicago, IL, USA) after arcsine transformation. Differences between means were analysed by one-way ANOVA followed by Fisher's least significant difference test for significance at P < 0.05. When the reconstructed buffalo embryos produced by hand-made clones were treated with 0, 50, or 75 nM TSA post-electrofusion for 10 h, the cleavage percentage (100.0 ± 0, 94.5 ± 2.3, and 96.1 ± 1.2, respectively) and blastocyst percentage (50.6 ± 2.3, 48.4 ± 2.7, and 48.1 ± 2.6, respectively), total cell number (274.9 ± 17.4, 289.1 ± 30.1, and 317.0 ± 24.2, respectively), and apoptotic index (3.4 ± 0.9, 4.5 ± 1.4, and 5.6 ± 0.7, respectively) in Day 8 blastocysts were not significantly different among different groups. The TSA treatment increased (P < 0.05) the global level of H4K5ac but not that of H3K18a in embryos treated with 50 or 75 nM TSA compared with that in controls. In contrast, the level of H3K27me3 was significantly lower (P < 0.05) in cloned embryos treated with 75 nM TSA than in embryos treated with 50 nM TSA or controls. The ultimate test of the reprogramming potential of any donor cell type is its ability to produce live offspring. To examine the in vivo developmental potential of the 0, 50, or 75 nM TSA treated embryos, we transferred Day 8 blastocysts, 2 each to 5, 6, and 5 recipients, respectively, which resulted in 2 pregnancies from 75 nM TSA treated embryos. However, one pregnancy was aborted in the first trimester and the other in the third trimester. In conclusion, TSA treatment of reconstructed embryos produced from semen-derived somatic cells alters their epigenetic status but does not improve the live birth rate. We are currently optimizing an effective strategy to improve the cloning efficiency of semen-derived somatic cells.

76 DEVELOPMENTAL CAPABILITY OF TRANSGENIC NUCLEAR-TRANSFERRED PIG EMBRYOS PRODUCED USING THE NOVEL METHOD OF PSEUDOPHYSIOLOGICAL ACTIVATION

2010 ◽  
Vol 22 (1) ◽  
pp. 196 ◽  
Author(s):  
M. Samiec ◽  
M. Skrzyszowska ◽  
R. Slomski
Keyword(s):  
Somatic Cell ◽  
Donor Cell ◽  
Fibroblast Cell ◽  
Original Method ◽  
Calcium Oscillations ◽  
Cell Nuclei ◽  
Novel Method ◽  
Transgenic Embryos

The physicochemical stimuli, which are commonly used for artificial activation of porcine nuclear-transferred (NT) oocytes, can affect detrimentally or cytotoxically the clonal cybrids and thereby inhibit the development or decrease the quality of cloned embryos. Therefore, we have recently developed a novel method of pseudophysiological transcomplementary (transcytoplasmic) activation to stimulate the developmental program of porcine oocytes reconstructed by somatic cell nuclear transfer. The mechanism underlying this original technique of activation is transcytoplasmic influx of sperm-derived proteins triggering intracellular calcium oscillations, which is mediated via heterologous (rabbit) zygote-descended cytoplasts. The purpose of our study was to estimate the in vitro developmental competences of porcine transgenic cloned embryos following pseudophysiological activation of oocytes receiving pWAPhGH-GFPBsd gene construct-nucleofected fetal fibroblast cell nuclei. In the cloning procedure, IVM pig oocytes were used as recipient cells for cell nuclei of positively selected transgenic fibroblast cells. The reconstruction of enucleated oocytes was performed by intracytoplasmic injection of either the somatic cell-derived karyoplast or whole tiny nuclear donor cell. The activation of porcine NT oocytes was achieved by electrofusion of them with the xenogeneic cytoplasts isolated from in vivo-derived rabbit zygotes (i.e. with the so-called zygoplasts), which led to the formation of triple xenocytoplasmic hybrids (xenocybrids). The rabbit zygotes had been flushed postmortem from the separated oviducts of superovulated postpubertal female donors 18 to 20 hafter administration of hCG and copulation. Single rabbit zygote-descended cytoplasts were inserted into the perivitelline space of previously reconstructed pig oocytes. The resulting zygoplast-NT oocyte couplets underwent fusion, which was induced by generation of 2 successive DC pulses of 1.2 kV cm-1 for 60 μs. The electrofusion medium consisted of 0.3 M Ca2+-deprived mannitol supplemented with 0.1 mM MgSO4 and 0.2 mg mL-1 fatty-acid-free BSA. The transcytoplasmically activated xenocybrids were cultured in vitro for 6 to 7 days up to morula/blastocyst stages. A total of 183/207 (88.4%) oocytes reconstructed with nucleofected fibroblast cell nuclei were successfully fused with zygoplasts. Out of 183 cultured NT embryos, 138 (75.4%) were cleaved. The rates of transgenic NT embryos that reached the morula and blastocyst stages yielded 106/183 (57.9%) and 65/183 (35.5%), respectively. In conclusion, the original method of pseudophysiological activation of porcine NT oocytes turned out to be relatively efficient, which has been confirmed by the high percentages of pWAPhGH-GFPBsd transgenic embryos developing in vitro to morula and blastocyst stages.

scholarly journals 36 IMPROVING THE APPLICATION OF NUCLEAR TRANSFER FOR PRODUCING NON-DOMESTIC FELIDS

2005 ◽  
Vol 17 (2) ◽  
pp. 168 ◽  
Author(s):  
M.C. Gomez ◽  
C.E. Pope ◽  
L. Lyons ◽  
A. Cole ◽  
M. Lopez ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Cell Lines ◽  
Nuclear Transfer ◽  
Implantation Rate ◽  
Domestic Cat ◽  
Developmental Competence ◽  
In Vitro Production ◽  
Fetal Survival

One of the most remarkable aspects of somatic cell nuclear transfer (NT) is the possibility of avoiding extinction when there are few remaining animals of a specific felid population. Previously, we produced live male African Wildcat (AWC; Felis lybica) cloned kittens using inter-species nuclear transfer (Gomez et al. 2004 Cloning and Stem Cells 6, 217–228). The production of females is a primary objective of most breeding programs. Therefore, the purpose of the present study was to determine (1) if we could produce live female AWC cloned kittens at a proportion similar to that previously demonstrated with males, and (2) if our inter-species NT technique used to produce AWC is applicable to in vitro production of another non-domestic felid species. Specifically, we evaluated the in vivo developmental competence of NT embryos derived by fusion of Black footed cat (BFC, Felis nigripes) and AWC fibroblasts with domestic cat (DSH, Felis catus) cytoplasts, after transfer into domestic cat recipients. Fibroblast cell lines were established from skin biopsies of BFC (6-year-old), and AWC (12-year-old) adult females. After at least three passages, cells were serum-starved for 5 days and injected into the perivitelline space of enucleated domestic cat oocytes. Fusion of cell-cytoplast couplets was induced by applying a 3-s AC pre-pulse of 20 V, 1 MHz, followed by two 30-μs DC pulses of 240 V/mm. Fused couplets were activated 2 to 3 h after fusion by exposure to two 60 μsec DC pulses of 120 V/mm, followed by 4 h incubation with 10 μg/mL cycloheximide and 5 μg/mL cytochalasin B. Reconstructed BFC (n = 16) and AWC (n = 536) NT Day 1 embryos were transferred by laparoscopy into the oviducts of 1 and 12 gonadotrophin-treated DSH recipients, respectively, on Day 1 after induced ovulation. Pregnancy was assessed by ultrasonography on Day 22. One cat (100%) receiving BFC NT embryos and 5 (41.6%) cats receiving AWC NT embryos became pregnant. Twenty-three AWC cloned embryos implanted and 11 kittens were born. Three BFC NT embryos implanted and the pregnancy is currently ongoing. AWC cloned kittens were phenotypically and genetically identical to their somatic cell donor. Their clonal identity was assessed by multiplex PCR amplification of 20 microsatellite markers, including seven markers that are known to be on the X chromosome. In summary, these results indicate that female AWC cloned kittens can be produced and BFC pregnancy can be established in domestic cat recipients. The embryo implantation rate and viability of AWC female cloned embryos was higher than that observed after the transfer of AWC male cloned embryos. The difference may be due to improvements in the NT procedure, rather than to differences in the sex of the cell lines. Table 1. Implantation rate and fetal survival to term of AWC and BFC NT embryos in pregnant domestic cat recipients

Effects of bovine oviduct epithelial cells, fetal calf serum and bovine serum albumin on gene expression in single bovine embryos produced in the synthetic oviduct fluid culture system

2005 ◽  
Vol 17 (8) ◽  
pp. 751 ◽  
Author(s):  
Mona E. Pedersen ◽  
Øzen Banu Øzdas ◽  
Wenche Farstad ◽  
Aage Tverdal ◽  
Ingrid Olsaker
Keyword(s):  
Gene Expression ◽  
Fetal Calf Serum ◽  
Calf Serum ◽  
Developmental Competence ◽  
Bovine Embryos ◽  
Glut 1 ◽  
Significant Difference ◽  
Oviduct Fluid

In this study the synthetic oviduct fluid (SOF) system with bovine oviduct epithelial cell (BOEC) co-culture is compared with an SOF system with common protein supplements. One thousand six hundred bovine embryos were cultured in SOF media supplemented with BOEC, fetal calf serum (FCS) and bovine serum albumin (BSA). Eight different culture groups were assigned according to the different supplementation factors. Developmental competence and the expression levels of five genes, namely glucose transporter-1 (Glut-1), heat shock protein 70 (HSP), connexin43 (Cx43), β-actin (ACTB) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), analysed as mRNA by using reverse transcription–polymerase chain reaction, were measured on bovine embryos cultured for 9 days. Gene expression of these in vitro-produced embryos was compared with the gene expression of in vivo-produced embryos. There was no significant difference found in embryo developmental competence between the Day 9 embryos in BOEC co-culture, FCS and BSA supplements in SOF media. However, differences in gene expression were observed. With respect to gene expression in in vivo and in vitro embryos, BOEC co-culture affected the same genes as did supplementation with FCS and BSA. HSP was the only gene that differed significantly between in vitro and in vivo embryos. When the different in vitro groups were compared, a significant difference between the BOEC co-culture and the FCS supplementation groups due to Glut-1 expression was observed.

62 REPROGRAMMING EVENTS AND DEVELOPMENTAL COMPETENCE OF RHESUS MONKEY EMBRYOS PRODUCED BY SOMATIC CELL NUCLEAR TRANSFER

2006 ◽  
Vol 18 (2) ◽  
pp. 139 ◽  
Author(s):  
S. Mitalipov ◽  
Q. Zhou ◽  
J. Byrne ◽  
W.-Z. Ji ◽  
D. Wolf
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Formation Rate ◽  
Embryonic Stem ◽  
Developmental Competence ◽  
Lamin A ◽  
Cell Nuclei ◽  
Blastocyst Development ◽  
Morula Stage

Successful reprogramming of somatic cell nuclei after nuclear transfer requires active remodeling by factors present in the nonactivated cytoplast. High levels of maturation promoting factor (MPF) activity are associated with this remodeling process which includes nuclear envelope breakdown (NEBD), premature chromosome condensation (PCC), and spindle formation. In this study, we examined the extent of nuclear remodeling in monkey somatic cell nuclear transfer (SCNT) embryos by monitoring the dynamics of lamin A/C appearance, as detected immunocytochemically, following fusion of donor cells with recipient cytoplasts. In the control, intracytoplasmic sperm injection (ICSI) fertilized embryos, lamin A/C was readily detected at the pronuclear stage but disappeared in early cleaving embryos only to reappear by the morula stage in association with the activation of the embryonic genome. We initially documented lack or incomplete NEBD and PCC in SCNT embryos in the form of retention of lamin A/C signal emanating from the donor nucleus. This observation was consistent with premature cytoplast activation due to the manipulation procedures. SCNT embryos produced by this approach typically arrested at the morula stage. Significant modifications in nuclear transfer protocols were then employed. Optimization of procedures resulted in robust NEBD and PCC, as indicated by loss of lamin A/C signal from the donor cell. Also, significant improvement of SCNT embryo development in vitro was observed, with a markedly improved blastocyst formation rate (21%). Several different fetal and adult somatic cell types screened as nuclear donors supported blastocyst development. SCNT blastocysts displayed a pattern of Oct-4 expression similar to that of sperm fertilized counterparts, indicative of efficient nuclear reprogramming. However, no pregnancies were established following a preliminary trial of 8 embryo transfers with 48 cloned embryos. Nevertheless, our results represent a breakthrough in efforts to produce cloned monkeys and should provide the resources required for the derivation of embryonic stem cells from SCNT blastocysts.

58 HISTONE DEACETYLASES INHIBITOR, SCRIPTAID, IS BENEFICIAL TO THE REPROGRAMMING OF SOMATIC NUCLEI FOLLOWING NUCLEAR TRANSFER

2009 ◽  
Vol 21 (1) ◽  
pp. 129
Author(s):  
J. G. Zhao ◽  
J. W. Ross ◽  
Y. H. Hao ◽  
D. M. Wax ◽  
L. D. Spate ◽  
...  
Keyword(s):  
Histone Acetylation ◽  
Histone Deacetylases ◽  
Nuclear Transfer ◽  
Blastocyst Stage ◽  
Untreated Group ◽  
Developmental Competence ◽  
Developmental Potential ◽  
Reconstructed Embryos

Somatic cell nuclear transfer (SCNT) is a promising technology with potential applications in both agriculture and regenerative medicine. The reprogramming of differentiated somatic nuclei into totipotent embryonic state following NT is not efficient and the mechanism is currently unknown. However, accumulating evidence suggests that faulty epigenetic reprogramming is likely to be the major cause of low success rates observed in all mammals produced through SCNT. It has been demonstrated that increased histone acetylation in reconstructed embryos by applying histone deacetylases inhibitor (HDACi) such as trychostatin A (TSA) significantly enhanced the developmental competence in several species in vitro and in vivo. However TSA has been known to be teratogenic. Compared with TSA, Scriptaid is a low toxic but more efficient HDACi (Su GH et al. 2000 Cancer Res. 60, 3137–3142). The objectives of this study were: 1) to investigate and optimize the application Scriptaid to the NT using Landrace fetal fibroblast cells (FFCs) as donor; 2) investigate the effect of increased histone acetylation on the developmental competence of reconstructed embryos from NIH mini inbred FFCs in vitro and in vivo. The reconstructed embryos were treated with Scriptaid at different concentrations (0 nm, 250 nm, 500 nm and 1000 nm) after activation for 14 to 16 h. IVF embryos without treatment were produced as an additional control. Developmental rates to the 2-cell and blastocyst stage were determined. Developmental potential was determined by transferring Day 1 NT zygotes to the oviducts of surrogates on the day of, or one day after, the onset of estrus. Experiments were repeated at least 3 times and data were analyzed with chi-square tests using SAS 6.12 program (SAS institute, Inc., Cary, NC, USA). The percentage blastocyst of cloned embryos using Landrace FFCs as donors treated with 500 nm Scriptaid was the highest and was significantly higher than untreated group (25% v. 11%, P < 0.05). Percent cleaved was not different among four treatment groups. We used 500 nm Scriptaid for 14 to 16 h after activation for all subsequent experiments. Developmental rate to the blastocyst stage was significantly increased in cloned embryos derived from NIH mini inbred FFCs after treating with Scriptaid (21% v. 9%, P < 0.05), while the blastocyst rate in IVF group was 30%. Embryo transfer (ET) results showed that 5/6 (Transferred embryos No. were 190, 109, 154, 174, 152, and 190, respectively) surrogates (83%) became pregnant resulting in 2 healthy piglets from 2 litters (recipients received 190 and 154 embryos, respectively) in the Scriptaid treatment group, while no pregnancies were obtained in the untreated group from 5 ET (Embryos transferred No. are 140, 163, 161, 151 and 151, respectively). These results suggest that 500 nm Scriptaid treatment following activation increase both the in vitro and in vivo development of porcine SCNT embryos from NIH mini inbred FFCs and the hyperacetylation might actually improve reprogramming of the somatic nuclei after NT. Funding from the National Institutes of Health National Center for Research Resources RR018877.

65 CLONED EMBRYOS FROM HORSE SOMATIC CELLS AND ENUCLEATED BOVINE AND OVINE OOCYTES AND THEIR DEVELOPMENTAL COMPETENCE

2008 ◽  
Vol 20 (1) ◽  
pp. 113
Author(s):  
H. M. Zhou ◽  
B. S. Li ◽  
L. J. Zhang
Keyword(s):  
Somatic Cell ◽  
Somatic Cells ◽  
Calf Serum ◽  
Cumulus Cells ◽  
Developmental Competence ◽  
Developmental Potential ◽  
Reconstructed Embryos ◽  
Electrical Pulses ◽  
Mongolian Horse

The objective of this study was to investigate the reprogramming potential of equine somatic cell donor nuclei in either bovine or ovine recipient oocyte cytoplasmic environments. Heterogeneous embryos were reconstructed by somatic cell nuclear transfer (NT). The percentage of fusion and developmental competence, assessed by rates of cleavage and morula and blastocyst formation, were determined. Skin fibroblast cells, obtained from the ear of an adult female Mongolian horse, were dissociated using 0.25% trypsin and cultured in vitro in a humidified atmosphere of 5% CO2 in air at 37°C. Donor somatic cells were serum-starved before NT and used between passages 4 and 6. Bovine and ovine oocytes derived from slaughterhouse ovaries were matured in vitro for 17–19 and 22–24 h, respectively, in a humidified atmosphere of 5% CO2 in air at 38.5°C, before they were enucleated and used as recipient cytoplasts. The fibroblasts were injected under the zona pellucida of the cytoplasts and electrically fused by 2 DC electrical pulses of 1.58 kV cm–1 for 10 μs, with an interval of 0.13 s. The reconstructed embryos were then activated with 5 μm ionomycin in H-M199 for 5 min and then in 2 mm 6-DMAP for 4 h. The equine-bovine and equine-ovine reconstructed embryos were co-cultured, respectively, with bovine and ovine cumulus cells in synthetic oviduct fluid supplemented with amino acids (SOFaa) and 10% fetal calf serum (FCS) for 168 h. The data were analyzed with ANOVA and differences among the groups were evaluated with t-test. The results of the percentages of fusion, cleavage, and development to morula (8 to 64 cells) and blastocyst stages of equine-bovine and equine-ovine heterogeneous embryos are shown in Table 1. This study demonstrates that heterogeneous embryos can undergo early embryonic divisions and that reprogramming of equine fibroblast nuclei can be initiated in foreign cytoplasts. It appears that embryos reconstructed with equine somatic nuclei and ovine cytoplasts have a higher developmental potential than those using bovine cytoplasts. Table 1. Developmental competence of equine-bovine and equine-ovine reconstructed embryos

56 EFFECTS OF PHYLOGENIC GENERA OF RECIPIENT CYTOPLASTS ON DEVELOPMENT AND VIABILITY OF CANADA LYNX (LYNX CANADENSIS) CLONED EMBRYOS

2010 ◽  
Vol 22 (1) ◽  
pp. 186 ◽  
Author(s):  
M. C. Gómez ◽  
J. I. Lyons ◽  
C. E. Pope ◽  
M. Biancardi ◽  
C. Dumas ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Donor Cell ◽  
Domestic Cat ◽  
Developmental Competence ◽  
Lynx Lynx ◽  
Phylogenetic Distance ◽  
Lynx Canadensis ◽  
Gestational Length ◽  
Canada Lynx ◽  
Oocyte Donor

Canada lynx (Lynx canadensis; CL) once occupied 16 states in the Unites States of America, but small populations remain in only 3 states. Interspecies-somatic cell nuclear transfer (Is-SCNT) offers the possibility of preventing their extinction; however, developmental constraints on Is-SCNT embryos are proportional to the phylogenetic distance between the donor cell and the recipient oocyte. Mitochondrial DNA (mtDNA) heteroplasmy may be involved in nuclear-cytoplasmic incompatibilities, thus inhibiting development of cloned embryos at the time of genomic activation. Minimizing the phylogenetic distance between the donor cell and recipient oocyte may enhance development of clone embryos. Caracal (Caracal caracal) may be suitable as an oocyte donor for SCNT and a recipient of CL cloned embryos because caracals hybridize with other felid species and share physical characteristics with the lynx family, marked by being previously classified in the lynx genera and having similar gestational length. To ensure compatibilities between the donor nuclei of the CL and the mitochondria of recipient oocytes, we (1) compared in vitro development of CL cloned embryos reconstructed with domestic cat (Felis catus; DSH) or caracal cytoplasts, (2) examined the mtDNA genotypes in CL cloned embryos, and (3) evaluated in vivo developmental competence of CL cloned embryos after transfer into caracal recipients. A total of 160 and 217 preovulatory oocytes were collected by laparoscopy from gonadotropin-treated caracals (n = 8) and DSH (n = 10) and used as recipient cytoplasts for reconstructing CL embryos. Results indicated that the phylogenetic genera of recipient cytoplasts did not affect embryo cleavage at Day 2 (caracal 50/55, 91% v. DSH 63/65, 97%), but development of CL cloned embryos to the blastocyst stage was higher when caracal oocytes were used as recipient cytoplasts (15/50; 30%) than with DSH cytoplasts (9/63, 14%; P < 0.05). The extent of mtDNA homoplasmy or heteroplasmy in CL cloned embryos was calculated by the number of single nucleotide polymorphisms (SNP) derived from the DSH or caracal oocyte donors and from the somatic cell donor CL. DNA was isolated from 25 and 35 CL cloned embryos reconstructed with caracal or DSH cytoplasts, respectively. All amplified products after PCR were sequenced and SNP analyzed. All CL embryos reconstructed with DSH cytoplasts were homoplasmic, carrying mtDNA only from the DSH oocyte donor (n = 35; SNP DSH = 2-6). Embryos reconstructed with caracal cytoplasts were homoplasmic for CL mtDNA (n = 9; SNPCL = 10-12) or heteroplasmic (caracal × CL, n = 17; SNPCL = 7-9; SNP caracal = 2-3). A total of 69 (mean = 34.5 ± 4.9 per caracal) and 70 (mean = 35.0 ± 9.8 per caracal) CL cloned embryos reconstructed with caracal and DSH cytoplasts, respectively, were transferred into 4 caracal recipients; however, no pregnancies were established. In summary, Is-SCNT between 2 phylogenetically closer species favors retention of the donor’s mitochondria, which might lead to a better nucleo-cytoplasmic interaction for reprogramming of donor nucleus.

79 PSEUDOPHYSIOLOGICAL TRANSCOMPLEMENTARY ACTIVATION OF GOAT OOCYTES RECEIVING ADULT EAR CUTANEOUS FIBROBLAST CELL NUCLEI

2010 ◽  
Vol 22 (1) ◽  
pp. 198
Author(s):  
M. Skrzyszowska ◽  
M. Samiec
Keyword(s):  
Somatic Cell ◽  
Plasma Membranes ◽  
Dermal Fibroblast ◽  
Fibroblast Cell ◽  
Vero Cells ◽  
Atmospheric Conditions ◽  
Cell Nuclei ◽  
Developmental Potential ◽  
Water Saturated

The aim of the study was to determine the in vitro developmental potential of caprine cloned embryos following pseudophysiological (transcytoplasmic) transcomplementary activation of oocytes reconstructed with ear skin-derived fibroblast cell nuclei. The source of nuclear recipient cells were IVM doe oocytes. The reconstruction of the previously enucleated oocytes (i.e. ooplasts) was performed by microinjection of either the somatic cell-derived karyoplasts or intact whole tiny nuclear donor cells directly into the cytoplasm. The reconstructed oocytes were incubated in Upgraded B2 INRA medium for 30 min to 1 h before their pseudophysiological activation. The activation was achieved by electrofusion of clonal cybrids with the allogeneic cytoplasts isolated from caprine IVF-created zygotes, which led to the formation of triple allocytoplasmic hybrids (allocybrids). These originate from 3 sources: (1) homologous whole nuclear donor fibroblast cells or their karyoplasts; (2) enucleated oocytes (ooplasts), and (3) zygote-derived cytoplasts. Single zygote-descended cytoplasts (the so-called zygoplasts) were inserted into the perivitelline space of previously reconstituted oocytes. The resulting zygoplast-clonal cybrid couplets were subsequently subjected to electrofusion, which was induced by application of a single DC pulse of 2.4 kV cm-1 for 15 μs. The electrofusion of zygoplast and reconstructed oocyte plasma membranes occurred in an isotonic dielectric solution deprived of Ca2+ ions. The transcytoplasmically activated clonal cybrids were cultured in vitro in Upgraded B2 INRA medium for 48 h at 38.5°C in a 100% water-saturated atmosphere of 5% CO2 and 95% air. Afterward, cleaved embryos were co-cultured with Vero cells in medium supplemented with 10% fetal bovine serum for an additional 96 to 144 h up to morula and blastocyst stages under the same thermal and atmospheric conditions. A total of 53/78 (67.9%) oocytes reconstructed with fibroblast cell nuclei were successfully fused with zygoplasts. From among 53 cultured cloned embryos, 34 (64.2%) cleaved. The rates of embryos that reached the morula and blastocyst stages were 21/53 (39.6%) and 11/53 (20.8%), respectively. In conclusion, the relatively high percentages of morulae and blastocysts were noticed among in vitro-cultured caprine cloned embryos produced by the strategy of pseudophysiological transcytoplasmic activation of oocytes reconstructed with adult dermal fibroblast cell nuclei. Therefore, the use of cytoplasmic components originating from zygotes as the stimuli for activation of nuclear-transferred oocytes appeared to be an effective procedure in the generation of goat blastocysts by somatic cell cloning.

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