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Kumbha R, Hosny N, Matson A, Steinhoff M, Hering BJ, Burlak C. Efficient production of GGTA1 knockout porcine embryos using a modified handmade cloning (HMC) method. Res Vet Sci 2019; 128:59-68. [PMID: 31722267 DOI: 10.1016/j.rvsc.2019.10.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/24/2019] [Accepted: 10/28/2019] [Indexed: 10/25/2022]
Abstract
Handmade cloning is a zona-free nuclear transfer approach and an economical, efficient, and simple micromanipulation-free alternative to dolly based traditional cloning (TC). In this study, based on handmade cloning with minor modifications, an optimized bi-oocyte fusion (BOF) cloning method was established to produce GGTA1 KO porcine embryos using the CRISPR/Cas9 gene editing system. The GGTA1 gene is responsible for the generation of Gal epitopes on the surface of porcine cells, triggering hyperacute immune rejection in preclinical porcine-to-human xenotransplantation. The purpose of the present study is to establish an efficient protocol for activation of porcine oocyte cytoplast-fibroblast fused constructs developed to GGTA1 KO blastocysts by the zona-free bi-oocyte fusion cloning method. High percentages of cleavage (90 ± 2.6%) and blastocyst rates (39 ± 4.0%) were achieved upon treatment with demecolcine-assisted oocyte enucleation followed by 6 V alternating current for proper alignment and single-step fusion technique using a single direct current pulse of 1.0 kV/cm for 9 μs duration, compared to the double-step fusion method with combined chemical activation using thimerosal and dithiothreitol. Overall blastocyst rate was higher for oocyte enucleation by demecolcine (0.4 μg/ml) and 45 min incubation (42 ± 1.5%) compared to without demecolcine incubation followed by complete chemical thimerosal/dithiothreitol activation (33 ± 1.1%). The blastocyst rate (39 ± 1.0%) was found to be significantly higher 1 h post-electrofusion, compared to at 0 and 4 h (28 ± 1.5 and 6 ± 1.5%, respectively). Blastocyst development rates for GGTA1 knockout embryos (38 ± 1.76%) were comparable to those obtained with wild-type embryos (41.1 ± 0.67%). In conclusion, we achieved high overall efficiency in production of GGTA1 KO blastocysts by modified HMC protocol.
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Affiliation(s)
- Ramesh Kumbha
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Nora Hosny
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, United States; Department of Medical Biochemistry and Molecular Biology, Suez Canal University Faculty of Medicine, Ismailia, Egypt
| | - Anders Matson
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Magie Steinhoff
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Bernhard J Hering
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Christopher Burlak
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, United States.
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2
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Bang J, Jin J, Ghanem N, Choi B, Fakruzzaman M, Ha A, Lee K, Uhm S, Ko D, Koo B, Lee J, Kong I. Quality improvement of transgenic cloned bovine embryos using an aggregation method: Effects on cell number, cell ratio, embryo perimeter, mitochondrial distribution, and gene expression profile. Theriogenology 2015; 84:509-23. [DOI: 10.1016/j.theriogenology.2015.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 02/26/2015] [Accepted: 04/11/2015] [Indexed: 01/16/2023]
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3
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Felmer R, Arias ME. Activation treatment of recipient oocytes affects the subsequent development and ploidy of bovine parthenogenetic and somatic cell nuclear transfer (SCNT) embryos. Mol Reprod Dev 2015; 82:441-9. [DOI: 10.1002/mrd.22492] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/13/2015] [Indexed: 12/11/2022]
Affiliation(s)
- R. Felmer
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera; Temuco Chile
- Faculty of Agriculture and Forestry; Department of Agricultural Sciences and Natural Resources; Universidad de La Frontera; Temuco Chile
| | - M. E. Arias
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera; Temuco Chile
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4
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Deng S, Li G, Zhang J, Zhang X, Cui M, Guo Y, Liu G, Li G, Feng J, Lian Z. Transgenic cloned sheep overexpressing ovine toll-like receptor 4. Theriogenology 2013; 80:50-7. [PMID: 23623352 DOI: 10.1016/j.theriogenology.2013.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 02/25/2013] [Accepted: 03/16/2013] [Indexed: 11/24/2022]
Abstract
An ovine fetal fibroblast cell line highly expressing TLR4 was established by inserting TLR4 into a reconstructive p3S-LoxP plasmid. Transgenic sheep overexpressing TLR4 were produced by transferring TLR4-transfected fetal fibroblasts into metaphase (M)II-stage enucleated oocytes (using SCNT). Because reconstructed embryos derived from MII-stage enucleated oocytes matured in vivo using a delayed-activated method had a higher pregnancy rate (18.52%) than that from MII-stage enucleated oocytes matured in vitro, the former procedure was used. Nine TLR4-transgenic live births were confirmed using polymerase chain reaction and Southern blot analysis. Increased expression of TLR4 at mRNA and protein levels in ear tissues of transgenic lambs were verified using reverse transcription polymerase chain reaction and immunohistochemistry, respectively. More toll-like receptor 4 protein was expressed by peripheral blood monocytes and/or macrophages collected from 3-month-old TLR4-transgenic than nontransgenic lambs at 0, 1, and 4 hours after lipopolysaccharide stimulation. Furthermore, interferon-γ and tumor necrosis factor α secreted by monocytes and/or macrophages of TLR4-transgenic lambs were significantly higher at 1 hour. Therefore, lipopolysaccharide-induced inflammatory responses from monocytes and/or macrophages occurred sooner in TLR4-transgenic lambs, consistent with an enhanced host immune response. In conclusion, transgenic sheep overexpressing TLR4 are a primary model to investigate the role of transgenic animals in disease resistance and have potential for breeding sheep with disease resistance.
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Affiliation(s)
- Shoulong Deng
- State Key Laboratory for AgroBiotechnology, China Agricultural University, Beijing, China
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5
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Selokar N, Shah R, Saha A, Muzaffar M, Saini M, Chauhan M, Manik R, Palta P, Singla S. Effect of post-fusion holding time, orientation and position of somatic cell-cytoplasts during electrofusion on the development of handmade cloned embryos in buffalo (Bubalus bubalis). Theriogenology 2012; 78:930-6. [DOI: 10.1016/j.theriogenology.2012.03.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 02/27/2012] [Accepted: 03/04/2012] [Indexed: 11/29/2022]
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6
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Nascimento AB, Albornoz MS, Che L, Visintin JA, Bordignon V. Synergistic effect of porcine follicular fluid and dibutyryl cyclic adenosine monophosphate on development of parthenogenetically activated oocytes from pre-pubertal gilts. Reprod Domest Anim 2011; 45:851-9. [PMID: 19416484 DOI: 10.1111/j.1439-0531.2009.01368.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study investigated the effect of porcine follicular fluid (PFF) and dibutyryl cyclic adenosine monophosphate (dbcAMP) during in vitro maturation (IVM) of porcine oocytes on meiotic maturation, fertilization and embryo development, and compared the effect of supplementing the embryo culture media with PFF or foetal bovine serum (FBS) on embryo development. Oocytes from pre-pubertal gilts were IVM for 44 h, and parthenogenetically activated or in vitro-fertilized. Embryos were cultured in porcine zygote medium (PZM3) for 7 days. Cleavage and blastocyst rates were evaluated at 48 h and 7 days of culture. The supplementation of the IVM medium with 25% PFF and 1 mm dbcAMP for the first 22 h resulted in more (p < 0.05) embryos developing to the blastocyst stage as compared with the inclusion of dbcAMP alone. The dbcAMP + PFF combination increased (p < 0.05) the average number of nuclei per blastocyst as compared with either of these components alone or in its absence. A synergistic effect of dbcAMP + PFF during IVM was also reflected in the capacity of oocytes to regulate sperm penetration and prevent polyspermy, as twice as many oocytes from the control group were penetrated by more than one sperm as compared with those matured in the presence of both dbcAMP and PFF. The supplementation of PZM3 with 10% FBS from days 5 to 7 of culture significantly improved the total cell quantity in embryos derived either from control or dbcAMP + PFF matured oocytes. There was no effect on the total cell quantity when FBS was replaced by the same concentration of PFF. These studies showed that dbcAMP, PFF and FBS can improve both the quantity (57.3% vs 41.5%) and quality (74.8 vs 33.3 nuclei) of porcine blastocysts derived from oocytes recovered of pre-pubertal gilts.
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Affiliation(s)
- A B Nascimento
- Departamento de Reprodução Animal, Faculdade de Medicina Veterinária, Universidade de São Paulo, SP, Brazil
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Lu F, Jiang J, Li N, Zhang S, Sun H, Luo C, Wei Y, Shi D. Effects of recipient oocyte age and interval from fusion to activation on development of buffalo (Bubalus bubalis) nuclear transfer embryos derived from fetal fibroblasts. Theriogenology 2011; 76:967-74. [PMID: 21752448 DOI: 10.1016/j.theriogenology.2011.04.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 04/26/2011] [Accepted: 04/26/2011] [Indexed: 10/18/2022]
Abstract
The objective was to investigate the effect of recipient oocyte age and the interval from activation to fusion on developmental competence of buffalo nuclear transfer (NT) embryos. Buffalo oocytes matured in vitro for 22 h were enucleated by micromanipulation under the spindle view system, and a fetal fibroblast (pretreated with 0.1 μg/mL aphidicolin for 24 h, followed by culture for 48 h in 0.5% fetal bovine serum) was introduced into the enucleated oocyte, followed by electrofusion. Both oocytes and NT embryos were activated by exposure to 5 μM ionomycin for 5 min, followed by culture in 2 mM 6-dimethyl-aminopurine for 3 h. When oocytes matured in vitro for 28, 29, 30, 31, or 32 h were activated, more oocytes matured in vitro for 30 h developed into blastocysts in comparison with oocytes matured in vitro for 32 h (31.3 vs 19.9%, P < 0.05). When electrofusion was induced 27 h after the onset of oocyte maturation, the cleavage rate (78.0%) was higher than that of electrofusion induced at 28 h (67.2%, P < 0.05), and the blastocyst yield (18.1%) was higher (P < 0.05) than that of electrofusion induced at 25 or 26 h (7.4 and 8.5%, respectively). A higher proportion of NT embryos activated at 3 h after electrofusion developed to the blastocyst stage (18.6%) in comparison with NT embryos activated at 1 h (6.0%), 2 h (8.3%), or 4 h (10.6%) after fusion (P < 0.05). No recipient was pregnant 60 d after transfer of blastocysts developed from NT embryos activated at 1 h (0/8), 2 h (0/10), or 4 h (0/9) after fusion. However, 3 of 16 recipients were pregnant following transfer of blastocysts developed from the NT embryos activated at 3 h after fusion, and two of these recipients maintained pregnancy to term. We concluded that the developmental potential of buffalo NT embryos was related to recipient oocyte age and the interval from fusion to activation.
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Affiliation(s)
- F Lu
- Animal Reproduction Institute, State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning, PR China
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8
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Liu J, Li LL, Du S, Bai XY, Zhang HD, Tang S, Zhao MT, Ma BH, Quan FS, Zhao XE, Zhang Y. Effects of interval between fusion and activation, cytochalasin B treatment, and number of transferred embryos, on cloning efficiency in goats. Theriogenology 2011; 76:1076-83. [PMID: 21752443 DOI: 10.1016/j.theriogenology.2011.05.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 05/03/2011] [Accepted: 05/03/2011] [Indexed: 11/15/2022]
Abstract
To improve the efficiency of somatic cell nuclear transfer (SCNT) in goats, we evaluated the effects of the interval between fusion and activation (1 to 5 h), cytochalasin B (CB) treatment after electrofusion, and the number of transferred embryos on the in vivo and in vitro development of cloned caprine embryos. The majority of the reconstructed embryos had condensed chromosomes and metaphase-like chromosomes at 2 and 3 h after fusion; cleavage and blastocyst rates from those two groups were higher (P < 0.05) than those of embryos activated 1, 4, or 5 h after fusion. Treatment with CB between fusion and activation improved in vitro and in vivo development of nuclear transfer (NT) goat embryos by reducing the fragmentation rate (P < 0.05). Although there were no significant differences in NT efficiency, pregnancy rate and kids born per recipient were increased by transfer of 20 or 30 embryos per recipient compared with 10 embryos. We concluded that CB treatment for 2 to 3 h between fusion and activation was an efficient method for generating cloned goats by somatic cell NT. In addition, increasing the number of embryos transferred to each recipient resulted in more live offspring from fewer recipients.
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Affiliation(s)
- J Liu
- Key Laboratory of Animal Reproductive Physiology and Embryo Technology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi Province, China
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9
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Kim JS, Song BS, Lee SR, Yoon SB, Huh JW, Kim SU, Kim E, Kim SH, Choo YK, Koo DB, Chang KT. Supplementation with estradiol-17β improves porcine oocyte maturation and subsequent embryo development. Fertil Steril 2011; 95:2582-4. [PMID: 21459376 DOI: 10.1016/j.fertnstert.2011.03.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 03/04/2011] [Accepted: 03/08/2011] [Indexed: 11/27/2022]
Abstract
Metaphase II oocyte production was significantly increased by treatment with E(2) during the first half of the total in vitro maturation (IVM) period, which was further evidenced by an increase in monospermic fertilization, blastocyst formation, or blastomere viability of IVF- or somatic cell nuclear transfer-derived embryos. Thus, we concluded that transient E(2) supplementation could improve the IVM rate and subsequent developmental competence in pigs.
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Affiliation(s)
- Ji-Su Kim
- National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology, Chungbuk, Republic of Korea
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10
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Ouellet G, Dubé J, Gauvin R, Laterreur V, Bouhout S, Bolduc S. Production of an optimized tissue-engineered pig connective tissue for the reconstruction of the urinary tract. Tissue Eng Part A 2011; 17:1625-33. [PMID: 21288158 DOI: 10.1089/ten.tea.2010.0324] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Nonurological autologous tissues are used for urethral reconstruction to correct urinary tract disorders but are still leading to complications. Other substitutes have been studied on small animal models without great success. For preclinical tests, we selected the porcine model for its similarity to the human urinary tract. Up to now, porcine skin fibroblasts were not able to synthesize enough extracellular matrix under standard conditions to sustain the formation of an adequate tissue for transplantation purposes. Therefore, our goal was to optimize the harvesting site and culture conditions to obtain a thick and easy to handle porcine fibroblast tissue. The oral mucosa was found to be the ideal harvesting site, and a culture temperature of 39°C enabled the formation of a good porcine fibroblast sheet. We successfully superimpose three fibroblast sheets that merged into a thick and resistant tissue where physiological extracellular matrix was produced. Mechanical resistance evaluation by uniaxial traction on the three-layer fibroblast constructs also demonstrated its suitable properties. The production of this porcine connective tissue offers an interesting option in the field of urological tissue engineering. Autologous experiments on a larger animal model are now possible and accessible, allowing the performance of long-term in vivo studies.
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Affiliation(s)
- Gabrielle Ouellet
- Laboratoire d'Organogénèse Expérimentale CMDGT/LOEX, Centre de recherche FRSQ du CHA universitaire de Québec et Département de Chirurgie, Université Laval, Québec, Québec, Canada
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11
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AKAGI S, YAMAGUCHI D, MATSUKAWA K, MIZUTANI E, HOSOE M, ADACHI N, KUBO M, TAKAHASHI S. Developmental Ability of Somatic Cell Nuclear Transferred Embryos Aggregated at the 8-cell Stage or 16- to 32-cell Stage in Cattle. J Reprod Dev 2011; 57:500-6. [DOI: 10.1262/jrd.10-140a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Satoshi AKAGI
- Animal Breeding and Reproduction Division, National Institute of Livestock and Grassland Science, NARO, Ibaraki 305-0901, Japan
| | - Daisuke YAMAGUCHI
- Ibaraki Prefectural North Livestock Hygiene Service Center, Ibaraki 310-0002, Japan
| | | | - Eiji MIZUTANI
- Animal Breeding and Reproduction Division, National Institute of Livestock and Grassland Science, NARO, Ibaraki 305-0901, Japan
| | - Misa HOSOE
- National Institute of Agrobiological Sciences, Ibaraki 305-8602, Japan
| | - Noritaka ADACHI
- Ibaraki Prefectural Livestock Research Center, Ibaraki 315-0132, Japan
| | - Masanori KUBO
- National Institute of Animal Health, NARO, Ibaraki 305-0856, Japan
| | - Seiya TAKAHASHI
- Headquarters, National Agriculture and Food Research Organization, Ibaraki 305-8517, Japan
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12
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You J, Song K, Lee E. Prolonged interval between fusion and activation impairs embryonic development by inducing chromosome scattering and nuclear aneuploidy in pig somatic cell nuclear transfer. Reprod Fertil Dev 2010; 22:977-86. [PMID: 20591332 DOI: 10.1071/rd09309] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 01/27/2010] [Indexed: 11/23/2022] Open
Abstract
The aim of the present study was to examine the effect of various intervals between electrofusion and activation (FA interval) on the nuclear remodelling and development of somatic cell nuclear transfer (SCNT) embryos in pigs. Reconstructed oocytes were activated at 0 (simultaneous fusion and activation; SFA), 1, 2 and 3 h (delayed activation) after electrofusion; these groups were designated as DA1, DA2 and DA3, respectively. When oocyte nuclear status was examined at 0.5, 1, 2 and 3 h after electrofusion, the incidence of chromosome scattering was increased (P < 0.01) as the FA interval was extended (0.0%, 12.0%, 77.3% and 78.0%, respectively). Extending the FA interval led to an increase (P < 0.01) in the percentage of oocytes containing multiple (>or=3) pseudopronuclei (PPN) (0.0% of SFA; 5.3% of DA1; 21.7% of DA2; and 33.5% of DA3). The development of SCNT embryos to the blastocyst stage was decreased (P < 0.05) in DA2 (5.7%) and DA3 (5.0%) compared with SFA (18.1%) and DA1 (19.5%). Our results demonstrate that extending the FA interval impairs the development of SCNT pig embryos by inducing chromosome scattering and the formation of multiple PPN, which may result in increased nuclear aneuploidy.
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Affiliation(s)
- Jinyoung You
- College of Veterinary Medicine, Kangwon National University, Chuncheon, Korea
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13
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Huang B, Cui K, Li T, Wang X, Lu F, Liu Q, da Silva FM, Shi D. Generation of Buffalo (Bubalus bubalis) Transgenic Chimeric and Nuclear Transfer Embryos Using Embryonic Germ-Like Cells Expressing Enhanced Green Fluorescent Protein. Reprod Domest Anim 2010; 45:103-8. [DOI: 10.1111/j.1439-0531.2008.01262.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Jeong YS, Oh KB, Park JS, Kim JS, Kang YK. Cytoplasmic localization of oocyte-specific variant of porcine DNA methyltransferase-1 during early development. Dev Dyn 2009; 238:1666-73. [PMID: 19449302 DOI: 10.1002/dvdy.21975] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
DNA methyltransferase-1 (Dnmt1) is involved in the maintenance of genomic methylation patterns. Rather than full-length Dnmt1, mouse oocytes have a truncated variant called Dnmt1o. Immunofluorescence data showed that Dnmt1o localized to the cytoplasm, but this has not been confirmed using more direct methods. The cytoplasmic localization of Dnmt1o has been assigned to the main cause of global DNA demethylation in early mouse embryos. We studied localization of Dnmt1o in mouse and pig embryos. We identified pig Dnmt1o protein and its transcript with unique 5'-end sequence. Physically separating mouse and pig 2-cell embryos into their nuclear and cytoplasmic components demonstrated that Dnmt1o of both species localized to the cytoplasm. Cloned pig embryos had Dnmt1o as the main form, with no indication of somatic Dnmt1. These findings indicate that Dnmt1o is cytoplasmic during early development; its presence in both pig and mouse embryos further suggests that Dnmt1o is conserved in mammals.
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Affiliation(s)
- Young Sun Jeong
- Development and Differentiation Research Center, KRIBB, Yuseong-gu, Daejeon, Korea
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15
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Cervera RP, Silvestre MA, Martí N, García-Mengual E, Moreno R, Stojkovic M. Effects of different oocyte activation procedures on development and gene expression of porcine pre-implantation embryos. Reprod Domest Anim 2009; 45:e12-20. [PMID: 19663811 DOI: 10.1111/j.1439-0531.2009.01509.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Among the factors that affect the efficiency of somatic cell nuclear transfer (SCNT) in pigs, the activation protocol is the most variable among the current SCNT procedures. The aim of this study is focused on defining an efficient activation treatment of porcine oocytes. In Experiment 1, we studied the effects of nine different oocyte activation procedures (including chemical- and electrical-based treatments) on parthenogenetic embryo development. In Experiment 2, we studied the effect of the more efficient activation procedures on the gene expression profile of Oct4 and Igf2r in parthenogenetic blastocysts. In conclusion, ionomycin as a first calcium stimulus is not able to activate porcine oocytes efficiently in comparison with electric procedures. Electrical treatments with 6-DMAP significantly increased the level of Oct4 expression, whereas the single and double pulse treatments alone maintained the same profile as the IVF group.
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Affiliation(s)
- R P Cervera
- Cellular Reprogramming Laboratory, Centro de Investigación Príncipe Felipe, Avenida Autopista del Saler, Valencia, Spain.
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16
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Khatir H, Anouassi A, Tibary A. In vitro and in vivo developmental competence of dromedary (Camelus dromedarius) oocytes following in vitro fertilization or parthenogenetic activation. Anim Reprod Sci 2009; 113:212-9. [DOI: 10.1016/j.anireprosci.2008.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 07/02/2008] [Accepted: 07/18/2008] [Indexed: 10/21/2022]
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17
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Oocyte activation procedures and influence of serum on porcine oocyte maturation and subsequent parthenogenetic and nuclear transfer embryo development. ZYGOTE 2008; 16:279-84. [DOI: 10.1017/s0967199408004796] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
SummaryThe viability of SCNT embryos is poor, with an extremely low cloned piglet production rate. In the present work, we studied the effect of three activation protocols based on ionomycin treatment (5 μM ionomycin for 5 min and incubated in 2 mM 6-DMAP for 3.5 h) or electric stimuli (two square wave electrical DC pulses of 1.2 kV/cm for 30 μs) combined or not with 6-DMAP on parthenogenetic embryo development. Oocytes activated by ionomycin plus 6-DMAP showed lower cleavage (47.2 vs. 78.5–81.5; p < 0.05) and blastocyst rates (11.3 vs. 29.2–32.1; p < 0.05) than those activated by electrical and electrical plus 6-DMAP treatments. Also, we studied the effect of addition of serum to maturation medium (0% vs. 10%) on nuclear maturation and further parthenogenetic and SCNT embryo development. We observed in the parthenogenetic embryos that cleavage rates in the serum-free group were significantly higher than in the serum-supplemented group (81.8 vs. 69.6% respectively; p < 0.05), although these differences were not detected in blastocyst rates or blastocyst nuclei numbers. Regarding SCNT embryos, no significant differences were observed in cleavage or blastocyst rates between different experimental groups of SCNT embryos. In conclusion, electrical pulse followed or not by 6-DMAP was found to be an efficient procedure to artificially activate MII porcine oocytes. Moreover, the addition of serum to oocyte maturation media did not seem to improve parthenogenetic or SCNT porcine embryo development.
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18
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Cong PQ, Kim ES, Song ES, Yi YJ, Park CS. Effects of fusion/activation methods on development of embryos produced by nuclear transfer of porcine fetal fibroblast. Anim Reprod Sci 2008; 103:304-11. [PMID: 17215095 DOI: 10.1016/j.anireprosci.2006.12.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Revised: 12/05/2006] [Accepted: 12/06/2006] [Indexed: 11/27/2022]
Abstract
The present studies were carried out to investigate the effects of intensity of dc pulse, number of dc pulse and equilibration before fusion/activation on developmental ability of porcine embryos derived from nuclear transfer. In experiment 1, different fusion/activation intensity (two dc pulses of 0.4, 0.8, 1.2, 1.6 and 2.0 kV/cm for 30 micros, respectively) was carried out to investigate development of embryos. In experiment 2, the reconstructed oocytes were fused and activated with one, two or three dc pulses of 1.2 kV/cm for 30 micros. In experiment 3, reconstructed oocytes were equilibrated in TCM-199 medium for 0-6 h, respectively, and fused/activated with one dc pulse of 1.2 kV/cm for 30 micros. The reconstructed embryos were cultured in PZM-3 medium containing 0.3% BSA. When oocytes were fused with donor cell by two dc pulses of 0.4 kV/cm for 30 micros, the rates of cleavage and blastocyst formation were significantly lower (32.9% and 2.5%) than those of fused by 0.8 kV/cm (59.0% and 17.4%) or 1.2 kV/cm (63.3% and 18.4%), respectively. One dc pulse of 1.2 kV/cm for 30 micros was enough to fuse and activate embryos to develop to blastocyst (24.8%). Equilibration for 2-3 h in TCM-199 before fusion/activation was beneficial for improving the developmental ability of embryos produced by nuclear transfer (25.6-23.3% at blastocysts).
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Affiliation(s)
- P Q Cong
- Division of Animal Science & Resources, Research Center for Transgenic Cloned Pigs, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejeon 305-764, South Korea
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Im GS, Samuel M, Lai L, Hao Y, Prather RS. Development and calcium level changes in pre-implantation porcine nuclear transfer embryos activated with 6-DMAP after fusion. Mol Reprod Dev 2007; 74:1158-64. [PMID: 17366547 PMCID: PMC2488272 DOI: 10.1002/mrd.20492] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study investigated the effect of treatment with 6-dimethylaminopurine (6-DMAP) following fusion on in vitro development of porcine nuclear transfer (NT) embryos. Frozen thawed ear skin cells were transferred into the perivitelline space of enucleated oocytes. Reconstructed oocytes were fused and activated with electric pulse in 0.3 M mannitol supplemented with either 0.1 or 1.0 mM CaCl(2). In each calcium concentration, activated oocytes were divided into three groups. Two groups of them were exposed to either ionomycin (I + 6-DMAP or 6-DMAP alone. In experiment 2, fused NT embryos in 0.3 M mannitol containing 1.0 mM CaCl(2) were exposed to 6-DMAP either immediately or 20 min after fusion/activation. For 0.1 mM CaCl(2), oocytes activated with either I + 6-DMAP or 6-DMAP alone showed a higher (P < 0.05) developmental rate to the blastocyst stage than those activated with an electric pulse alone (26.7 and 22.5 vs. 12.5%). For 1.0 mM CaCl(2), oocytes activated with either I + 6-DMAP or 6-DMAP alone showed significantly higher (P < 0.05) developmental rate to the blastocyst stage (35.6 and 28.3 vs. 19.8%). Developmental rate to the blastocyst stage was (P < 0.05) increased in NT embryos activated with 6-DMAP 20 min after fusion. 6-DMAP made a higher and wider Ca(2+) transient compared to that induced by electric pulses (Fig. 3). The fluctuation lasted during the time that oocytes were cultured in 6-DMAP. Regardless of Ca(2+) concentration in fusion medium, activation with 6-DMAP following electric pulses supported more development of porcine NT embryos. Activation of NT embryos with 6-DMAP after fusion in the presence of 1.0 mM CaCl(2) could support better developmental rate to the blastocyst stage.
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Affiliation(s)
- Gi-Sun Im
- Division of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211
- National Livestock Research Institute, RDA, Suwon, 441-706, Korea
| | - Melissa Samuel
- Division of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211
| | - Liangxue Lai
- Division of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211
| | - Yanhong Hao
- Division of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211
| | - Randall S. Prather
- Division of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211
- Corresponding author. Tel.: +1-573-882-6414; fax: +1-573-884-7827. E-mail address: (Randall S. Prather). 920 East Campus Drive, E125D ASRC, University of Missouri-Columbia, Columbia, MO, 65211 U.S.A
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20
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Exogenous dibutyryl cAMP affects meiotic maturation via protein kinase A activation; it stimulates further embryonic development including blastocyst quality in pigs. Theriogenology 2007; 69:290-301. [PMID: 17977589 DOI: 10.1016/j.theriogenology.2007.09.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Revised: 08/23/2007] [Accepted: 09/19/2007] [Indexed: 11/21/2022]
Abstract
High concentrations of cyclic AMP in germinal vesicle oocytes generally inhibit GVBD. Thus, maintaining the GV stage in growing oocytes is essential for the developmental competence of the eggs. In this study, we traced the effects of dibutyryl cyclic AMP on meiotic maturation and early embryonic development in pigs. We also investigated several blastocyst qualities, including structural integrity, mitochondrial membrane potential, and apoptosis, which are affected by dbcAMP. To determine whether increased concentrations of cAMP inhibit GVBD, we explored the meiotic patterns and during maturation of pig oocytes. When treated with dbcAMP for 22h, 91.1% of the oocytes were arrested in the GV stage compared to only 38.8% of the oocytes in the control group (P<0.05). After completion of IVM, a higher proportion of the dbcAMP-treated oocytes were in metaphase II than the untreated ones (91.3% vs. 72.8%, P<0.05). Western blot analysis showed a reduction (at 22h) and/or increase (at 44h) in MPF and MAP kinase activities in porcine oocytes treated with dbcAMP for the first 22h of IVM compared to the untreated control. We also confirmed that protein kinase A activity increased in dbcAMP-treated oocytes, indicating an elevated intracellular concentration of cAMP. After IVF, the frequency of polyspermy in the dbcAMP-treated group decreased compared to that in the control group (22.4% vs. 47.4%, P<0.05). Furthermore, blastocyst formation, the blastocyst cell number, mitochondrial membrane potential, and apoptosis were enhanced and/or reduced by dbcAMP in both IVF and SCNT embryos. We concluded that synchronizing meiotic resumption by dbcAMP treatment improved the developmental capacity and embryonic qualities of IVF and SCNT embryos by increasing the mitochondrial membrane potential and decreasing the incidence of apoptosis in preimplantation-stage porcine embryos.
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21
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Campbell KHS, Fisher P, Chen WC, Choi I, Kelly RDW, Lee JH, Xhu J. Somatic cell nuclear transfer: Past, present and future perspectives. Theriogenology 2007; 68 Suppl 1:S214-31. [PMID: 17610946 DOI: 10.1016/j.theriogenology.2007.05.059] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
It is now over a decade since the birth, in 1996, of Dolly the first animal to be produced by nuclear transfer using an adult derived somatic cell as nuclear donor. Since this time similar techniques have been successfully applied to a range of species producing live offspring and allowing the development of transgenic technologies for agricultural, biotechnological and medical uses. However, though applicable to a range of species, overall, the efficiencies of development of healthy offspring remain low. The low frequency of successful development has been attributed to incomplete or inappropriate reprogramming of the transferred nuclear genome. Many studies have demonstrated that such reprogramming occurs by epigenetic mechanisms not involving alterations in DNA sequence, however, at present the molecular mechanisms underlying reprogramming are poorly defined. Since the birth of Dolly many studies have attempted to improve the frequency of development, this review will discuss the process of animal production by nuclear transfer and in particular changes in the methodology which have increased development and survival, simplified or increased robustness of the technique. Although much of the discussion is applicable across species, for simplicity we will concentrate primarily on published data for cattle, sheep, pigs and mice.
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Affiliation(s)
- K H S Campbell
- Animal Development and Biotechnology Group, School of Biosciences, University of Nottingham, Sutton Bonnington, Loughborough LE12 5RD, UK.
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22
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Jeong YS, Yeo S, Park JS, Lee KK, Kang YK. Gradual development of a genome-wide H3-K9 trimethylation pattern in paternally derived pig pronucleus. Dev Dyn 2007; 236:1509-16. [PMID: 17474127 DOI: 10.1002/dvdy.21150] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The cytoplasm of a mature oocyte contains many protein complexes that are programmed to restructure incoming sperm chromatins on fertilization. Of the complicated biochemical events that these functional machineries control, the most impressive and important is epigenetic reprogramming. Despite its importance in epigenetic resetting, or "de-differentiation," of gamete genomes back to an incipient status, the mechanisms of epigenetic reprogramming do not seem to be conserved among mammals. Here, we report that, unlike in the mouse, the pig sperm-derived pronucleus is markedly trimethylated at lysine 9 of histone H3 (H3-m(3)K9), which might be associated with preservation of paternally derived cytosine methylation in pig zygotes. The male H3-m(3)K9 pattern is gradually established during pronucleus development, and this process occurs independently of DNA replication. Considering these unique epigenetic features, the pig zygote is, we believe, suited to serve as another model of epigenetic reprogramming that is antithetical to the well-characterized mouse model.
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Affiliation(s)
- Young Sun Jeong
- Center for Development and Differentiation, KRIBB, Yuseong-gu, Daejon, South Korea
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23
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Wang E, Yu Y, Li X, Jiao L, Wang L. Effects of different nuclear transfer and activation methods on the development of mouse somatic cell cloned embryos. CHINESE SCIENCE BULLETIN-CHINESE 2007. [DOI: 10.1007/s11434-007-0031-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Yamanaka KI, Sugimura S, Wakai T, Shoji T, Kobayashi J, Sasada H, Sato E. Effect of Activation Treatments on Actin Filament Distribution and In Vitro Development of Miniature Pig Somatic Cell Nuclear Transfer Embryos. J Reprod Dev 2007; 53:791-800. [PMID: 17420620 DOI: 10.1262/jrd.18162] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the present study, we investigated the effect of activation treatments on the actin filament distribution and in vitro development of somatic cell nuclear transfer (SCNT) embryos in miniature pigs. We combined three activation methods, ionomycin (ION), electrical stimulation (ES), and cycloheximide treatment (CH), to prepare seven activation treatments (ION, ES, CH, ION + CH, ION + ES, ES + CH and ION + ES + CH). First, we investigated the activation rate of oocytes and in vitro development of parthenotes. The activation rates of the oocytes in the ION, ES, CH, ION + CH, ION + ES, ES + CH, and ION + ES + CH groups were 42.9, 51.3, 0.0, 82.1, 80.6, 78.1 and 78.6%, respectively, showing that the rates of the combined treatment groups were significantly higher (P<0.05) than those of the single treatment groups. Although there were no significant differences in the activation rates of the combined treatment groups, the developmental rate to blastocysts in the ION + CH treatment group (36.1%) was significantly higher (P<0.05) than the other combined treatment groups (14.6-24.7%). Subsequently, we investigated the in vitro development and distribution of microfilaments in SCNT embryos. The developmental rate to blastcysts of the SCNT embryos in the ION + CH treatment group (11.3%) was significantly higher (P<0.05) than in the ES and ION + ES + CH treatment groups (4.5 and 5.2%, respectively). The rate of normal actin filament distribution in the SCNT embryos activated with ION + CH was significantly higher (P<0.05) than those activated with ES or ION + ES + CH treatment (63.3 vs. 46.8 or 46.4%). In addition, the fragmentation rate of the SCNT embryos activated with ION + CH was significantly lower (P<0.05) than those activated with ION + ES + CH (14.9 vs. 26.1%). The present results suggest that an activation treatment of ionomycin combined with cycloheximide may avoid physical damage to microfilaments and result in improved subsequent development of miniature pig SCNT embryos.
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Affiliation(s)
- Ken-ichi Yamanaka
- Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University
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25
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Kwon DJ, Park CK, Yang BK, Kim CI, Cheong HT. Effects of maturational age of recipient oocytes and activation conditions on the development of porcine fetal fibroblast nuclear transfer embryos. Anim Reprod Sci 2006; 100:211-5. [PMID: 17011146 DOI: 10.1016/j.anireprosci.2006.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Revised: 09/01/2006] [Accepted: 09/05/2006] [Indexed: 10/24/2022]
Abstract
This study was conducted to evaluate the nuclear remodeling patterns and the developmental potential of porcine fetal fibroblast nuclear transfer embryos (NTs) following the maturational age of recipient oocytes and activation conditions. Donor cells were transferred into the enucleated oocytes that were matured for 36 or 44h. Electrofused embryos were cultured in PZM-3 for 6 days without activation treatment (EF group). Some of these embryos were additionally activated by electric stimulus (ES; EF+ES group) or a combination of ES and DMAP (EF+ES+D group) before culture. The reconstituted embryos were fixed 2.5h after fusion to evaluate the nuclear remodeling patterns. The nuclear remodeling pattern of NTs reconstituted with 44 h-matured recipients showed a tendency to form a pronucleus-like structure, while that of NTs reconstituted with 36 h-matured recipients showed a tendency to undergo a premature chromosome condensation (PCC) and form one set of chromatin clump. In EF+ES+D group, blastocyst development was significantly increased regardless of maturational age of recipient oocytes (P<0.05). The result indicates that additional activation treatment is necessary to induce the activation of embryos reconstituted with 36 h-matured recipients, and treatment with the combination of electrical stimuli and DMAP could enhance the blastocyst formation rate of porcine NTs reconstituted with both 36 h- and 44 h-matured recipient oocytes.
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Affiliation(s)
- D J Kwon
- College of Animal Life Science, Kangwon National University, Chuncheon 200-701, Republic of Korea
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26
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Zhang YH, Pan DK, Sun XZ, Sun GJ, Liu XH, Wang XB, Tian XH, Li Y, Dai YP, Li N. In vitro developmental competence of pig nuclear transferred embryos: effects of GFP transfection, refrigeration, cell cycle synchronization and shapes of donor cells. ZYGOTE 2006; 14:239-47. [PMID: 16822335 DOI: 10.1017/s0967199406003716] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Accepted: 09/30/2005] [Indexed: 11/06/2022]
Abstract
SummaryThe present study was designed to evaluate the feasibility of producing pig transgenic blastocysts expressing enhanced green fluorescent protein (GFP) and to examine the effects of shape and preparation methods of donor cells on in vitro developmental ability of pig nuclear transferred embryos (NTEs). In experiment 1, the effect of GFP transfection on development of pig NTEs was evaluated. The cleavage and blastocyst rates showed no significant difference between NTEs derived from transfected and non-transfected donors. In experiment 2, the effect of different nuclear donor preparation methods on in vitro development of NTEs was examined. The cleavage rate showed no statistically significant differences among three preparation methods. The blastocyst rates of donor cells treated once at −4 °C and those of freshly digested cells were similar to each other (26.3% vs 17.9%). The lowest blastocyst rates (5.88%) were observed when cells cryopreserved at −196 °C were used as donors. In experiment 3, the effect of different cell cycle synchronization methods on the in vitro development potential of pig NTEs was evaluated. The cleavage rate of NTEs derived from cycling cells was much better than that of NTEs derived from serum-starved cells (64.4% vs 50.5%, p < 0.05), but no significant difference was observed between the the blastocyst rates of the two groups. In experiment 4, the effect of different shapes of cultured fibroblast cells on the in vitro development of pig NTEs was examined. The fusion rate for couplets derived from rough cells was poorer than that observed in couplets derived from round smooth cells (47.8% vs 76.8%, p < 0.05). However, there were no significant differences observed in the cleavage rate and blastocyst rate. In conclusion, the present study indicated that (i) refrigerated pig GFP-transfected cells could be used as donors in nuclear transfer and these NTEs could be effectively developed to blastocyst stage; (ii) serum starvation of GFP-transfected cells is not required for preimplantation development of pig NTEs; and (iii) a rough surface of GFP-transfected donor cells affects fusion rate negatively but has no influence on the cleavage rate or blastocyst rate of pig NTEs.
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Affiliation(s)
- Yun-Hai Zhang
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
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27
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Meena CR, Das SK. Development of water buffalo (Bubalus bubalis) embryos from in vitro matured oocytes reconstructed with fetal skin fibroblast cells as donor nuclei. Anim Reprod Sci 2006; 93:258-67. [PMID: 16182475 DOI: 10.1016/j.anireprosci.2005.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Revised: 06/30/2005] [Accepted: 07/01/2005] [Indexed: 10/25/2022]
Abstract
The present study was carried out to explore the feasibility of using buffalo fetal skin fibroblasts as donor nuclei and to find out the developmental competence of embryos following transfer of these nuclei to in vitro matured enucleated buffalo oocytes. Skin cells were isolated from 1 to 2-month-old fetuses obtained from slaughterhouse, by enzymatic digestion (0.5% w/v trypsin +0.05% w/v collagenase in Dulbecco's PBS) for 15-20 min. The cells were washed 4 times with Dulbecco's PBS and then once with RPMI-1640+10% FBS by centrifugation at 600 x g. The cells were then cultured in the same medium in a CO2 incubator (5% CO2 in air) at 38.5 degrees C for 2-3 days. Cumulus-oocyte complexes (COCs) collected from slaughterhouse buffalo ovaries were subjected to IVM in the IVM medium (TCM-199 + 5 microg/ml FSH-P + 10 microg/ml LH+10% FBS) for 20-22 h in a CO2 incubator (5% CO2 in air) at 38.5 degrees C. Oocytes were denuded with 0.1% trypsin followed by repeated pipetting and then enucleated by aspirating the first polar body with 10-15% of nearby cytoplasm with a micromanipulator. Two different types of donor cells (growing cells and those arrested with cytochalasin-B) were used for reconstruction of oocytes. The reconstructs were electro fused and incubated in the activation medium (TCM-199 + 8 microg/ml cytochalasin-B+10% FBS) for 4 h. These were then cultured in IVC medium (TCM-199+10% FBS) in a CO2 incubator (5% CO2 in air) at 38.5 degrees C for 48 h. The cleaved embryos were then co-cultured with buffalo oviduct cells in embryo development media (EDM). Out of 119 denuded matured oocytes which were enucleated and reconstructed with growing cells, 78 (65.5%) were electro fused, activated and cultured, out of which 4 (5.1%) reconstructs cleaved and developed to 2-cell stage, 3 (3.8%) reached to 4-cell stage and 3 (3.8%) reached to 8-cell stage. In the synchronized group, out of 62 denuded matured oocytes which were reconstructed with cytochalasin-B blocked cells, 40 (65%) were electrofused, activated and cultured, out of which 4 (10%) developed to 2-cell stage, 3 (7.50%) to 4-cell stage, 2 (5.0%) to early morula stage and 1 (2.50%) to blastocysts stage. These results suggest that buffalo fetal skin fibroblasts could be used as donor nuclei for the production of buffalo embryos after nuclear transfer to enucleated in vitro matured buffalo oocytes.
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Affiliation(s)
- C R Meena
- Animal Biotechnology Centre, National Dairy Research Institute, Karnal 132001, Haryana, India
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28
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Jellerette T, Melican D, Butler R, Nims S, Ziomek C, Fissore R, Gavin W. Characterization of calcium oscillation patterns in caprine oocytes induced by IVF or an activation technique used in nuclear transfer. Theriogenology 2006; 65:1575-86. [PMID: 16243386 DOI: 10.1016/j.theriogenology.2005.08.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Accepted: 08/30/2005] [Indexed: 11/19/2022]
Abstract
Routine activation of nuclear transfer (NT) eggs involves the application of a single intracellular calcium [Ca2+]i rise, stimulated by an electrical pulse, as opposed to [Ca2+]i oscillations, which is the natural mode of sperm-induced activation at fertilization in all mammalian species tested to date. It has yet to be shown that caprine oocytes exhibit an increase in calcium at fertilization in a manner similar to other mammals. The objective of the present study was to evaluate and characterize the ([Ca2+]i) oscillation patterns of caprine metaphase II (MII) oocytes during IVF and during an activation techniques used in nuclear transfer. Additionally, the effect of cytochalasin B (cyto B) in the NT process was evaluated for its impact on [Ca2+]i oscillations and subsequent embryo development. Mature in vitro and in vivo derived caprine oocytes were activated by 5 microM ionomycin, an electrical pulse(s), or IVF. The intracellular Ca2+ response was determined using the [Ca2+]i indicator Fura-2 dextran (Fura-2D). Ova treated with ionomycin or stimulated by an electrical pulse exhibited a single [Ca2+]i rise, whereas IVF-derived oocytes showed oscillations. IVF [Ca2+]i showed some variation, with 62% of in vitro matured oocytes exhibiting oscillations, whereas 8% of in vivo matured oocytes exhibited oscillations demonstrating a correlation between [Ca2+]i responses and maturation technique. Knowing the [Ca2+]i profile of activated eggs, one may be able to optimize the activation methodology used in a production nuclear transfer setting which could potentially improve development to term for NT embryos.
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Affiliation(s)
- Teru Jellerette
- GTC Biotherapeutics Inc., 175 Crossing Boulevard, Framingham, MA 01702, USA
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29
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Shen PC, Lee SN, Wu JS, Huang JC, Chu FH, Chang CC, Kung JC, Lin HH, Chen LR, Shiau JW, Yen NT, Cheng WTK. The effect of electrical field strength on activation and development of cloned caprine embryos. Anim Reprod Sci 2006; 92:310-20. [PMID: 16159700 DOI: 10.1016/j.anireprosci.2005.05.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2004] [Revised: 04/12/2005] [Accepted: 05/10/2005] [Indexed: 10/25/2022]
Abstract
The activation procedure used in nuclear transfer (NT) is one of the critical factors affecting the efficiency of animal cloning. The purpose of this study was to compare the effect of two electrical field strengths (EFS) for activation on the developmental competence of caprine NT embryos reconstructed from ear skin fibroblasts of adult Alpine does. The NT embryos were obtained by transfer of the quiescent fibroblasts at the fourth passage into the enucleated metaphase II (M II) oocytes. Four to five hours after electrical fusion, the NT-embryos were activated by EFS either at 1.67 or at 2.33 kV/cm and immediately incubated in 6-DMAP (2 mM) for 4 h. The cleavage rate of the NT-embryos activated with 2.33 kV/cm was greater than that activated with 1.67 kV/cm after in vitro culture for 18 h (65.6% versus 19.6%, p < 0.001). No pregnancy was found in 14 recipient does after transferring 51 NT embryos at 1-2 cell stages activated with 1.67 kV/cm. In contrast, two of the seven recipients were pregnant and gave birth to three kids after transferring 61 NT embryos at 1-2 cell stages activated by 2.33 kV/cm. The birth weights of three cloned kids were within the normal range of Alpine goats. However, one kid died 1h after birth while the remaining two are still healthy. DNA analysis by polymerase chain reaction (single-strand conformation polymorphism, SSCP) confirmed that the three kids were genetically identical to the nuclear donor.
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Affiliation(s)
- P C Shen
- Department of Animal Science, National Pingtung University of Science and Technology, Pingtung 912, Taiwan, ROC
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30
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El Shourbagy SH, Spikings EC, Freitas M, St John JC. Mitochondria directly influence fertilisation outcome in the pig. Reproduction 2006; 131:233-45. [PMID: 16452717 DOI: 10.1530/rep.1.00551] [Citation(s) in RCA: 237] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The mitochondrion is explicitly involved in cytoplasmic regulation and is the cell’s major generator of ATP. Our aim was to determine whether mitochondria alone could influence fertilisation outcome.In vitro, oocyte competence can be assessed through the presence of glucose-6-phosphate dehydrogenase (G6PD) as indicated by the dye, brilliant cresyl blue (BCB). Using porcinein vitrofertilisation (IVF), we have assessed oocyte maturation, cytoplasmic volume, fertilisation outcome, mitochondrial number as determined by mtDNA copy number, and whether mitochondria are uniformly distributed between blastomeres of each embryo. After staining with BCB, we observed a significant difference in cytoplasmic volume between BCB positive (BCB+) and BCB negative (BCB−) oocytes. There was also a significant difference in mtDNA copy number between fertilised and unfertilised oocytes and unequal mitochondrial segregation between blastomeres during early cleavage stages. Furthermore, we have supplemented BCB−oocytes with mitochondria from maternal relatives and observed a significant difference in fertilisation outcomes following both IVF and intracytoplasmic sperm injection (ICSI) between supplemented, sham-injected and non-treated BCB−oocytes. We have therefore demonstrated a relationship between oocyte maturity, cytoplasmic volume, and fertilisation outcome and mitochondrial content. These data suggest that mitochondrial number is important for fertilisation outcome and embryonic development. Furthermore, a mitochondrial pre-fertilisation threshold may ensure that, as mitochondria are diluted out during post-fertilisation cleavage, there are sufficient copies of mtDNA per blastomere to allow transmission of mtDNA to each cell of the post-implantation embryo after the initiation of mtDNA replication during the early postimplantation stages.
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Affiliation(s)
- Shahinaz H El Shourbagy
- The Mitochondrial and Reproductive Genetics Group, The Medical School, The University of Birmingham, Birmingham B15 2TT, UK
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31
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Im GS, Seo JS, Hwang IS, Kim DH, Kim SW, Yang BC, Yang BS, Lai L, Prather RS. Development and apoptosis of pre-implantation porcine nuclear transfer embryos activated with different combination of chemicals. Mol Reprod Dev 2006; 73:1094-101. [PMID: 16736528 DOI: 10.1002/mrd.20455] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Artificial activation of oocytes is a pre-requisite for successful cloning by nuclear transfer (NT). This study investigated effect of different combination of activation chemicals such as electric pulse (E), thimerosal (Thi) + dithiothreitol (DTT), 6-dimethylaminopurine (6-DMAP), or cycloheximide (CH) on the developmental ability and the frequency of apoptosis of porcine NT embryos during the culture in vitro. NT embryos activated with chemicals showed significantly higher developmental rate to blastocyst stage compared to embryos activated with E alone (21.5%-26.6% vs. 15.7%, respectively). Of chemicals, Thi + DTT supported higher development to blastocyst stage as compared to 6-DMAP or CH (26.6% vs. 21.5%-23.4%, respectively). Apoptosis of NT embryos were analyzed by using a terminal deoxynucleatidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) assay. The onset of apoptosis of embryos activated E alone was on Day 4, whereas embryos activated with chemicals showed apoptosis on Day 3 post-activation NT embryos exposed to chemicals for activation had higher frequency of apoptosis compared to that of embryos exposed to E alone from Day 3 to Day 7 during the culture. In conclusion, this study shows that chemical activation after fusion could increase not only the developmental ability of porcine NT embryos but also the mean cell number with an increased ratio of inner cell mass (ICM) to trophectoderm (TE) cells. However, the chemical activation also could increase the frequency of apoptosis and induced apoptosis earlier in porcine NT embryos.
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Affiliation(s)
- Gi-Sun Im
- Division of Animal Sciences, University of Missouri-Columbia, 65211, USA
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32
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Koo DB, Chae JI, Kim JS, Wee G, Song BS, Lee KK, Han YM. Inactivation of MPF and MAP kinase by single electrical stimulus for parthenogenetic development of porcine oocytes. Mol Reprod Dev 2005; 72:542-9. [DOI: 10.1002/mrd.20382] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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33
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Melican D, Butler R, Hawkins N, Chen LH, Hayden E, Destrempes M, Williams J, Lewis T, Behboodi E, Ziomek C, Meade H, Echelard Y, Gavin W. Effect of serum concentration, method of trypsinization and fusion/activation utilizing transfected fetal cells to generate transgenic dairy goats by somatic cell nuclear transfer. Theriogenology 2005; 63:1549-63. [PMID: 15763100 DOI: 10.1016/j.theriogenology.2004.05.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2003] [Accepted: 05/01/2004] [Indexed: 10/26/2022]
Abstract
This work was performed within a commercial nuclear transfer program to investigate different methods for synchronizing donor cell cycle stage, for harvesting donor cells, and for fusion and activation of reconstructed caprine embryos. Primary fetal cells isolated from day 35 to day 40 fetuses were co-transfected with DNA fragments encoding both the heavy and light immunoglobulin chains of three different monoclonal antibodies and neomycin resistance. Four neomycin resistant cell lines for each antibody were selected, expanded, and aliquots were both cryopreserved for later use as karyoplast donors or used for further genetic characterization. Transfected fetal cells were cultured in 0.5% FBS to synchronize G0/G1 cell cycle stage cells, then re-fed with 10% FBS prior to use to allow donor cells to re-enter the cell cycle. Alternatively, transfected fetal cells were grown to confluence in 10% FBS to induce contact inhibition to synchronize G0/G1 cell cycle stage cells. Adherent monolayers of transfected fetal donor cells were harvested by either partial or complete trypsinization. Donor cells were simultaneously fused and activated with enulceated in vivo produced ovulated oocytes from superovulated does. Half of the fused couplets received an additional electrical activation pulse and non-fused couplets were re-fused. Four live offspring were produced from 587 embryos generated from cell lines cultured in 0.5% FBS, while one live offspring was produced from 315 embryos generated from cell lines cultured in 10% FBS (0.7% versus 0.3% embryos transferred, respectively, P > 0.05). Five offspring were produced from 633 embryos generated from cell lines harvested by partial trypsinization (0.8% embryos transferred), and no offspring were produced from 269 embryos generated from cell lines harvested by complete trypsinization. Four live offspring were produced from 447 embryos generated from re-fused couplets, and one live offspring was produced from 230 embryos generated from fused couplets that received an additional electrical activation pulse (0.9% versus 0.4% embryos transferred, respectively, P > 0.05). These results suggest that low-serum culture of transfected goat fetal cells and harvest by partial trypsinization may be more efficient methods for generating transgenic goats by somatic cell nuclear transfer. In addition, re-fusion of non-fused couplet or an additional activation step was successful for producing live offspring.
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Affiliation(s)
- David Melican
- GTC Biotherapeutics, 300 Charlton Road, Spencer, MA 01562, USA
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Choi JY, Kim CI, Park CK, Yang BK, Cheong HT. Effect of activation time on the nuclear remodeling and in vitro development of nuclear transfer embryos derived from bovine somatic cells. Mol Reprod Dev 2005; 69:289-95. [PMID: 15349840 DOI: 10.1002/mrd.20131] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study was conducted to investigate the effect of recipient activation time on the chromatin structure and development of bovine nuclear transfer embryos. Serum-starved skin cells were electrofused to enucleated oocytes, activated 1-5 hr after fusion, and cultured in vitro. Some fused eggs were fixed at each time point after fusion without activation, or 3 or 7 hr after activation. Some nocodazole treated zygotes were fixed to analyze their chromosome constitutions. The proportion of eggs with a morphologically normal premature chromosome condensation (PCC) state increased 1-2 hr after fusion. Whereas eggs with elongated chromosome plate increased as activation time was prolonged to 3 hr, and 5 hr after fusion, 58.1% of eggs showed more than two scattered chromosome sets. The proportion of eggs with a single chromatin mass (40.6-56.7%) significantly increased when eggs were activated within 2.5 hr after fusion (P < 0.05). Only 23.3% of reconstituted embryos activated 5 hr after fusion formed one pronucleus-like structure (PN), whereas, 64.5-78.3% of embryos activated 1-2.5 hr after fusion formed one PN. The proportion of embryos with normal chromosome constitutions decreased as activation time was prolonged. Development rates to the blastocyst stage were higher in eggs activated within 2 hr after fusion (17.3-21.7%) compared to those of others (0-8.6%, P < 0.05). The result of the present study suggests that activation time can affect the chromatin structure and in vitro development of bovine nuclear transfer embryos.
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Affiliation(s)
- Jong-Yeob Choi
- Faculty of Animal Resource, College of Animal Resource Science, Kangwon National University, Chuncheon, Korea
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Hölker M, Petersen B, Hassel P, Kues WA, Lemme E, Lucas-Hahn A, Niemann H. Duration of In Vitro Maturation of Recipient Oocytes Affects Blastocyst Development of Cloned Porcine Embryos. CLONING AND STEM CELLS 2005; 7:35-44. [PMID: 15996116 DOI: 10.1089/clo.2005.7.35] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study investigated the effects of different incubation periods for oocyte maturation and contact inhibition of donor cells as well as different osmolarities for storage of recipient oocytes on fusion rates, cleavage rates, and blastocyst yields of porcine somatic nuclear transfer (SCNT) derived embryos. In addition, the in vivo developmental potential of cloned embryos derived from the most promising SCNT protocol was tested by transfer to recipient gilts. Storage of in vitro-matured oocytes for 7.5 h in calcium-free TL-HEPES medium at 295 or 320 mOsmol prior to activation yielded significantly (p < 0.05) higher parthenogenetic blastocyst rates compared to storage in TL-HEPES with an osmolarity of 270 mOsmol (24.4 +/- 3.0% and 26.2 +/- 4.3% vs. 18.3 +/- 6.4%, respectively, mean +/- SD) and improved the visibility of the polar body. Electrical fusion of fibroblasts to enucleated oocytes matured for 38, 40, or 42 h resulted in similar fusion and cleavage rates (74.8-84.4%). However, nuclear transfer with oocytes matured for 40 h in vitro yielded significantly higher (p < 0.05) development to the blastocyst stage after 7 days of culture (14.7 +/- 1.7%) than with oocytes matured for 38 h (9.5 +/- 2.1%) or 42 h (5.1 +/- 2.1%). Contact inhibition for 24, 48, or 72 h significantly (p < 0.05) increased the proportion of cells at G0/G1 compared with cycling fibroblasts. However, duration of contact inhibition of the donor cells for either 24, 48, or 72 h had no effect on blastocyst rates of SCNT embryos. Four gilts received an average of 150 SCNT embryos (range 138-161) reconstructed with oocytes matured for 40 h; two of these became pregnant; one of them went to term and farrowed four piglets on day 115 of pregnancy. Microsatellite analysis confirmed that the clones were genetically identical with the donor cells. These results show that changes of the in vitro maturation protocol may affect in vitro development of reconstructed porcine embryos, while duration of the contact inhibition period plays a minor role for the success of porcine SCNT. The effects on in vivo development are yet to be determined.
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Affiliation(s)
- Michael Hölker
- Department of Biotechnology, Institute for Animal Breeding, Mariensee, Germany
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Koo DB, Kang YK, Park JS, Park JK, Chang WK, Lee KK, Han YM. A paucity of structural integrity in cloned porcine blastocysts produced in vitro. Theriogenology 2004; 62:779-89. [PMID: 15251229 DOI: 10.1016/j.theriogenology.2003.12.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2003] [Accepted: 12/01/2003] [Indexed: 11/18/2022]
Abstract
The structural integrity of blastocyst stage embryos, consisting of the inner cell mass (ICM) and trophectoderm (TE) cells, is a prerequisite for normal development after implantation in mammals. In this study, allocation of nuclear transfer (NT)-derived porcine blastocysts to the ICM and to the TE cells was examined and compared with IVF- and in vivo-derived embryos. NT-derived embryos had a lower developmental competence to the blastocyst stage than IVF-derived embryos (P < 0.05). Total cell number of NT-derived blastocysts was inferior to that of IVF-derived embryos (P < 0.05), although no difference was detected between the two groups in the ratio of ICM to total cells. However, in vivo-derived blastocysts had a higher proportion of ICM to total cells compared with in vitro-produced embryos (P < 0.01). To investigate what proportions of in vitro-produced porcine embryos represent normal structural integrity, differentially-stained blastocysts were individually classified into three presumptive groups (I: <20%; II: 20-40%; III: >40%) according to the ratio of ICM to total cells. Low proportions of NT- (12.5%, 7/56) and IVF-derived blastocysts (15.8%, 9/57) were assigned to Group II, presumptively having a normal range of structural integrity, whereas, almost all in vivo-derived embryos (97.5%, 39/40) were allocated to Group II. In conclusion, limited structural integrity may lead to the poor survival to term of NT- or IVF-derived porcine embryos produced in vitro.
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Affiliation(s)
- Deog-Bon Koo
- Laboratory of Development and Differentiation, Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-dong, Yuseong, Daejeon 305-806, Republic of Korea
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Eckardt S, McLaughlin KJ. Interpretation of reprogramming to predict the success of somatic cell cloning. Anim Reprod Sci 2004; 82-83:97-108. [PMID: 15271446 DOI: 10.1016/j.anireprosci.2004.04.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In the context of mammalian somatic cell cloning, the term reprogramming refers to the processes that enable a somatic cell nucleus to adopt the role of a zygotic nucleus. Gene re-expression is one measure of reprogramming if correlated with subsequent developmental potential. This paper describes several experiments utilizing pre-implantation gene expression to evaluate reprogramming and clone viability. We have established a direct correlation between Oct4 expression in mouse clones at the blastocyst stage and their potential to maintain pluripotent embryonic cells essential for post-implantation development. Furthermore, the quality of gene expression in clones dramatically improves when genetically identical clones are combined in clone-clone aggregate chimeras. Clone--clone aggregates exhibit a higher developmental potential than single clones both in vitro and in vivo. This could be mediated by complementation between blastomeres from epigenetically different clones within the aggregate rather than by the increase in cell number resulting from aggregation. We also discuss the use of tetraploid embryos as a model to evaluate reprogramming using gene expression and demonstrate that somatic cell nuclei can be reprogrammed by blastomeres to re-express embryonic specific genes but not to contribute to post-implantation development.
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Affiliation(s)
- Sigrid Eckardt
- Center for Animal Transgenesis and Germ Cell Research, New Bolton Center, University of Pennsylvania, New Bolton Center, 382 West Street Road, Kennett Square, PA 19348, USA
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Lee SH, Kim DY, Nam DH, Hyun SH, Lee GS, Kim HS, Lee CK, Kang SK, Lee BC, Hwang WS. Role of messenger RNA expression of platelet activating factor and its receptor in porcine in vitro-fertilized and cloned embryo development. Biol Reprod 2004; 71:919-25. [PMID: 15151927 DOI: 10.1095/biolreprod.103.026138] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Platelet activating factor (PAF) is known as an autocrine growth/survival factor in mammalian preimplantation embryos. This study investigated the expression of porcine PAF receptor (PAFr) mRNA and its role in porcine in vitro fertilized (IVF) or somatic cell nuclear transfer (SCNT) embryo development. The expression of PAFr mRNA in IVF or SCNT blastocysts was shown by reverse transcription-polymerase chain reaction (RT-PCR) and Southern blot analysis. Semiquantitative RT-PCR and Southern blot analysis demonstrated that PAFr mRNA was expressed during preimplantation embryo development, it was highly expressed through the 2-cell to 8-cell embryo stage, and it decreased at the morula stage. PAFr mRNA expression was detected steadily in IVF embryos, whereas it was varied at the 2-cell, 4-cell, and blastocyst stages in SCNT embryos. To determine the role of PAF in IVF and SCNT embryo development, embryos were cultured in North Carolina State University (NCSU)-23 medium supplemented with different concentrations of PAF (0, 0.037, 0.37, 3.72, or 37.2 nM). The PAF supplement significantly increased the rate of blastocyst formation in SCNT embryos, but not in IVF embryos. The PAF supplement for the entire 168 h of culture showed significantly higher blastocyst formation in SCNT embryos. Upregulation of PAFr mRNA by PAF in SCNT embryos indicated that the embryotrophic effect of PAF was mediated through its functional receptors in SCNT embryos. In conclusion, the present study demonstrated that PAFr mRNA was expressed in porcine IVF and SCNT embryos, and that PAF supplement improved the developmental competence of SCNT embryos through its specific receptors.
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Affiliation(s)
- So Hyun Lee
- Department of Theriogenology and Biotechnololgy, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea
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Im GS, Lai L, Liu Z, Hao Y, Wax D, Bonk A, Prather RS. In vitro development of preimplantation porcine nuclear transfer embryos cultured in different media and gas atmospheres. Theriogenology 2004; 61:1125-35. [PMID: 15037000 DOI: 10.1016/j.theriogenology.2003.06.006] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2003] [Accepted: 06/20/2003] [Indexed: 10/27/2022]
Abstract
This study investigated the effect of culture media and gas atmospheres on the development of porcine nuclear transfer embryos. Oocytes derived from a local abattoir were matured for 42-44 h and enucleated. Fetal fibroblasts were prepared from a Day 35 porcine fetus. Confluent stage fetal fibroblasts were introduced into the perivitelline space of enucleated oocytes. Fusion and activation were induced simultaneously with two direct current (1.2 kV/cm for 30 micros) in 0.3 M mannitol medium. For parthenogenetic activation, the same pulses were used. In Experiment 1, parthenogenetically activated oocytes were cultured in North Carolina State University-23 (NCSU-23), Porcine Zygote Medium-3 (PZM-3), or Beltsville Embryo Culture Medium-3 (BECM-3). Parthenogenetically activated oocytes cultured in PZM-3 had a higher (P < 0.05) developmental rate to the blastocyst stage (15.2% versus 3.7-9.6%) as compared to BECM-3 or NCSU-23. The number of nuclei in Day 6 blastocysts was higher (P < 0.05) in PZM-3 (23.6) and NCSU-23 (21.4) than BECM-3 (14.2). In Experiment 2, parthenogenetically activated oocytes were cultured in NCSU-23 under a gas atmosphere of 5% CO(2) in air for 6 days (T1), 5% CO(2), 5% O(2), 90% N(2) for 6 days (T2), 5% CO(2) in air for 3 days, then 5% CO(2), 5% O(2), 90% N(2) for 3 days (T3), or 5% CO(2), 5% O(2), 90% N(2) for 3 days, then 5% CO(2) in air for 3 days (T4). Blastocyst formation rates were not different among treatments (12.9 =/-3.6 %, 13.5 +/- 4.2%, 10.8+/-2.4%, and 12.6+/-2.7%, respectively). However, T2 (36.7+/-2.9) and T3 (33.8+/-3.0) resulted in more nuclei per blastocyst than T1 (23.2+/-2.1) or T4 (26.0+/-2.1 ). In Experiment 3, reconstructed porcine nuclear transfer (NT) embryos were cultured in NCSU-23 or PZM-3 under a gas atmosphere of 5% CO(2) in air or 5% CO(2), 5% O(2), 90% N(2). Developmental rates to blastocyst stage for porcine NT embryos cultured in NCSU-23 under a gas atmosphere of 5% CO(2) in air or 5% CO(2), 5% O(2), 90% N(2) were 7.2+/-1.4% and 12.3+/-1.4%, and the number of nuclei was 12.2=/-0.8% and 19.4+/-1.0, respectively. NT embryos cultured in PZM-3 under a gas atmosphere of 5% CO(2) in air or 5% CO(2), 5% O(2), 90% N(2) had developmental rates to blastocyst stage of 18.8+/-1.9 %, and 17.8+/-3.8% the nuclei number was 20.9 +/- 1.9 and 21.9+/-3.3, respectively. NT embryos cultured in NCSU-23 had a higher developmental rate to the blastocyst stage in 5% CO(2), 5% O(2), 90% N(2) than in 5% CO(2) in air (P < 0.05). Regardless of gas atmospheres, NT embryos cultured in PZM-3 had a higher developmental rate (18.3 =/- 1.7% versus 16.9 +/- 1.2%) and nuclei number (21.4 +/-1.8 versus 16.9 +/- 1.2) than in NCSU-23 (P < 0.05). In conclusion, a gas atmosphere of 5% CO(2), 5% O(2), 90% N(2) supported a higher development rate of porcine NT embryos than 5% CO(2) in air when the porcine NT embryos were cultured in NCSU-23. Furthermore, regardless of atmosphere, PZM-3 supported a higher development rate of porcine nuclear transfer embryos than NCSU-23.
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Affiliation(s)
- Gi-Sun Im
- Department of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211, USA
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Kim YS, Lee SL, Ock SA, Balasubramanian S, Choe SY, Rho GJ. Development of cloned pig embryos by nuclear transfer following different activation treatments. Mol Reprod Dev 2004; 70:308-13. [PMID: 15625691 DOI: 10.1002/mrd.20211] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This study compared the effects of activation treatments on the development and ploidy of nuclear transferred (NT) pig embryos. After in vitro maturation of oocytes collected from the slaughterhouse, oocytes were enucleated and reconstructed by transfer of donor cells and fusion with three DC pulses (1.4 kV/cm, 20 musec). Oocytes were pulsed thrice electrically with 1.4 kV/cm for 20 musec and NT eggs were divided into three treatment groups: Group 1 (no further treatment), Group 2 (10 mug/mL cycloheximide [CHX], 3 hr), and Group 3 (1.9 mM 6-dimethylaminopurine [DMAP], 3 hr). All the eggs were cultured in sets of 30 in 60 muL drops of NCSU-23 supplemented with 4 mg/mL fatty acid free BSA, and compared for the rates of development and ploidy. The rates of cleavage, development, and total cell number of parthenotes in Group 3 were significantly (P < 0.05) higher than those in Groups 1 and 2. Cleavage rates of NT embryos in Group 1 were significantly (P < 0.05) lower than those in Groups 2 and 3 (73% vs. 81% and 82%, respectively). Development into blastocyst stage and total cell number of NT embryos in Group 3 were significantly (P < 0.05) higher than those in Groups 1 and 2. Although the embryos in Group 3 had higher development, approximately 58% of NT embryos evaluated were abnormal ploidy (6% haploidy, 9% polyploidy, and 42% mixoploid). The results suggested that although DMAP enhanced development and higher cell number, due attention should be paid to abnormal ploidy in pig NT embryos.
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Affiliation(s)
- Yang-Sil Kim
- College of Veterinary Medicine, Gyeongsang National University, Chinju, Republic of Korea 660-701
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Zhu J, King T, Dobrinsky J, Harkness L, Ferrier T, Bosma W, Schreier LL, Guthrie HD, DeSousa P, Wilmut I. In VitroandIn VivoDevelopmental Competence of Ovulated andIn VitroMatured Porcine Oocytes Activated by Electrical Activation. CLONING AND STEM CELLS 2003; 5:355-65. [PMID: 14733753 DOI: 10.1089/153623003772032853] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The objective of this study was to evaluate the in vitro and in vivo developmental competence of parthenogenetic (parthenote) pig embryos derived from ovulated and in vitro matured (IVM) oocytes. A total of four experiments were carried out. These demonstrated that the mean blastocyst rates from stimulated ovulated and IVM pig oocytes were not significantly different (61% vs. 46%, p > 0.05) following in vitro culture. Both ovulated and IVM pig parthenotes were able to develop in vivo for 30 days. Parthenote fetuses collected 21 and 30 days post estrus were morphologically normal but significantly smaller and lighter than fertilized controls (p < 0.01). IVM pig parthenotes stopped development around 31 days post estrus.
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Affiliation(s)
- Jie Zhu
- Department of Gene Expression and Development, The Roslin Institute, Midlothian, EH 25 9PS, Scotland, United Kingdom
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Boiani M, Eckardt S, Leu NA, Schöler HR, McLaughlin KJ. Pluripotency deficit in clones overcome by clone-clone aggregation: epigenetic complementation? EMBO J 2003; 22:5304-12. [PMID: 14517267 PMCID: PMC204490 DOI: 10.1093/emboj/cdg507] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abnormal gene expression patterns in somatic cell clones and their attrition in utero are commonly considered a consequence of errors in nuclear reprogramming. We observe that mouse clone blastocysts have less than half the normal cell number, and that higher cell number correlates with correct expression of Oct4, a gene essential for peri-implantation development and embryonic pluripotency. To increase the cell number, we aggregated genetically identical clones at the 4-cell stage. Clone-clone aggregates did not form more blastocysts, but the majority expressed Oct4 normally and had higher rates of fetal and postnatal development. Fertilized blastocysts with low cell numbers, induced by removal of two blastomeres at the 4-cell stage, did not exhibit abnormal Oct4 expression, indicating that improved gene expression and post-implantation development of clone-clone aggregates is not a consequence of increased cell number. Rather, we propose that complementation of non-cell-autonomous defects of genetically identical, but epigenetically different, embryos results in improved gene expression in clone-clone aggregates.
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Affiliation(s)
- Michele Boiani
- Germline Development Group, Center for Animal Transgenesis and Germ Cell Research, New Bolton Center, University of Pennsylvania, Kennett Square, PA 19348, USA
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Lee GS, Kim HS, Hyun SH, Kim DY, Lee SH, Nam DH, Jeong YW, Kim S, Kang SK, Lee BC, Hwang WS. Improved developmental competence of cloned porcine embryos with different energy supplements and chemical activation. Mol Reprod Dev 2003; 66:17-23. [PMID: 12874794 DOI: 10.1002/mrd.10329] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The present study investigated the effect of lactate/pyruvate supplement in culture medium and of chemical activation after electric stimulus on in vitro development of porcine somatic cell nuclear transfer (SCNT) embryos. In vitro matured gilt oocytes were enucleated, reconstructed with fetal fibroblasts, and simultaneously fused/activated using a single pulse of 2.0 kV/cm for 30 microsec. In Experiment 1, reconstructed embryos were cultured in North Carolina State University (NCSU)-23 medium supplemented with either 5.5 mM glucose (Group A) or lactate (5.0 mM)/pyruvate (0.5 mM) (Group B). Compared to Group A, cleavage rate (64% vs. 47%) was higher and more blastocysts developed in Group B (17% vs. 6% at Day 6, 21% vs.11% at Day 7). Experiment 2, embryos reconstructed by electric stimulus (2.0 kV/cm for 30 microsec) were subjected to three activation protocols: (1) no chemical activation (Group C), (2) 7.5 microg/ml cytochalasin B treatment at 2 hr after electric stimulus (Group D), and (3) 5 microg/ml 6-dimethylaminopurine (Group E) treatment at 2 hr after electric stimulus. The reconstructed embryos were cultured for 7 days in NCSU-23 medium supplemented with lactate (5.0 mM)/pyruvate (0.5 mM). The rates of blastocyst formation on Day 6 and Day 7 in Group C (17 and 20%, respectively) or Group D (15, 20%, respectively) were higher than in Group E (9 and 12%, respectively). The percentage of two pseudo-pronucleus (PPN) formations in Group D (88%) was significantly higher than in Group C (71%) and Group E (72%). Mean cell numbers of blastocysts in Group D (63.4 +/- 15.8) were higher than in Group C (43.9 +/- 16.5) and Group E (32.9 +/- 17.9), due to increased trophectoderm (TE) cell numbers. Our results indicate that supplementing NCSU-23 medium with lactate/pyruvate and exposure of cytochalasin B after electrical stimulus can improve in vitro developmental competence of porcine SCNT embryos.
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Affiliation(s)
- Gab-Sang Lee
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
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Hao Y, Lai L, Mao J, Im GS, Bonk A, Prather RS. Apoptosis and in vitro development of preimplantation porcine embryos derived in vitro or by nuclear transfer. Biol Reprod 2003; 69:501-7. [PMID: 12700186 DOI: 10.1095/biolreprod.103.016170] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Apoptosis occurs during preimplantation development in both in vivo- and in vitro-produced embryos, and it may contribute to embryonic loss. The present study investigated the development of porcine nuclear transfer (NT) embryos reconstructed by using fetal fibroblasts as compared to embryos produced by in vitro fertilization (IVF). The onset and the frequency of apoptosis in NT and IVF embryos were examined via morphological and nuclear changes and TUNEL assay. The NT blastocysts had a similar number of nuclei as compared to IVF blastocysts and appeared to be morphologically similar. Relative to IVF embryos, the NT embryos had a lower cleavage rate (42.7% vs. 71.0%) and a lower developmental rate (11.1% vs. 28.6%) to the blastocyst stage. The earliest positive TUNEL signals were detected in the NT embryos on Day 5 of culture. The percentage of cells undergoing apoptosis in the NT embryos was higher than that of the IVF embryos and increased with time in vitro. Some of the abnormal morphological changes observed during early development related to apoptosis. Cytoplasmic fragmentation, developmental arrest, and nuclear condensation were typical characteristics of embryos undergoing apoptosis. Some mechanisms of the apoptotic pathway were triggered by changes in the NT embryos. The developmental rates of NT embryos might be improved by identifying specific apoptotic pathways and then intervening in these pathways to improve development.
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Affiliation(s)
- Yanhong Hao
- Department of Animal Sciences, University of Missouri-Columbia, Columbia, Missouri 65211, USA
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46
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In vitro development of reconstructed goat oocytes after somatic cell nuclear transfer with fetal fibroblast cells. Small Rumin Res 2003. [DOI: 10.1016/s0921-4488(03)00014-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Lee GS, Hyun SH, Kim HS, Kim DY, Lee SH, Lim JM, Lee ES, Kang SK, Lee BC, Hwang WS. Improvement of a porcine somatic cell nuclear transfer technique by optimizing donor cell and recipient oocyte preparations. Theriogenology 2003; 59:1949-57. [PMID: 12600732 DOI: 10.1016/s0093-691x(02)01294-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This study was conducted to improve a porcine somatic cell nuclear transfer (SCNT) technique by optimizing donor cell and recipient oocyte preparations. Adult and fetal fibroblasts, and cumulus and oviduct cells were used as donor cells, and in vivo- and in vitro-matured oocytes were employed as recipient oocytes. The percentages of fusion and development to the blastocyst stage, the ratio of blastocysts to 2-cell embryos, and cell number of blastocysts were monitored as experimental parameters. In Experiment 1, donor cells of four different types were transferred to enucleated oocytes matured in vitro, and more (P < 0.05) blastocysts were derived from SCNT of fetal fibroblasts than from that of other cells (15.9% versus 3.1-7.9%). For SCNT using fetal fibroblasts, increasing the number of subcultures up to 15 times did not improve developmental competence to the blastocyst stage (12.2-16.7%). In Experiment 2, fetal fibroblasts were transferred to enucleated oocytes that matured in vivo or in vitro. When parthenogenetic activation of both types of oocytes was conducted as a preliminary control treatment, a significant increase in blastocyst formation was found for in vivo-matured compared with in vitro-matured oocytes (36.4% versus 29.5%). However, no improvement was achieved in SCNT using in vivo-matured oocytes. In conclusion, the type of donor somatic cell is important for improving development after porcine SCNT, and fetal fibroblasts were the most effective among examined cells. A system with good reproducibility has been established using fetal fibroblasts as the donor karyoplast after subculturing 1-10 times, and using both in vivo and in vitro-matured oocytes as the recipient cytoplast.
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Affiliation(s)
- Gab-sang Lee
- Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, South Korea
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48
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Liu TM, Yu XM, Ye YZ, Zhou JF, Wang ZW, Tong JG, Wu CJ. Factors affecting the efficiency of somatic cell nuclear transplantation in the fish embryo. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 2002; 293:719-25. [PMID: 12410600 DOI: 10.1002/jez.10177] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Procedures to improve somatic cell nuclear transplantation in fish were evaluated. We reported effects of nonirradiated recipient eggs, inactivated recipient eggs, different combinations between recipient eggs and donor cells, duration of serum starvation, generation number, and passage number of donor cells on developmental rates of nuclear transplant (NT) embryos. Exposure to 25,000 R of gamma-rays inactivated recipient eggs. Single nucleus of cultured, synchronized somatic cell from gynogenetic bighead carp (Aristichthys nobilis) was transplanted into nonirradiated or genetically inactivated unfertilized egg of gibel carp (Carassius auratus gibelio). There was no significant difference in developmental rate between nonirradiated and inactivated recipient eggs (27.27% vs. 25.71%, respectively). Chromosome count showed that 70.59% of NT embryos contained 48 chromosomes. It showed that most NT embryos came from donor nuclei of bighead carp, which was supported by microsatellite analysis of NT embryos. But 23.53% of NT embryos contained more than 48 chromosomes. It was presumed that those superfluous chromosomes came from nonirradiated recipient eggs. Besides, 5.88% of NT embryos were chimeras. Eggs of blunt-snout bream (Megalobrama amblycephala) and gibel carp were better recipient eggs than those of loach (Misgurnus anguillicaudatus) (25% and 18.03% vs. 8.43%). Among different duration of serum starvation, developmental rate of NT embryos from somatic nuclei of three-day serum starvation was the highest, reaching 25.71% compared to 14.14% (control), 20% (five-day), and 21.95% (seven-day). Cultured donor cells of less passage facilitated reprogramming of NT embryos than those of more passage. Recloning might improve the developmental rate of NT embryos from the differentiated donor nuclei. Developmental rate of fourth generation was the highest (54.83%) and the lowest for first generation (14.14%) compared to second generation (38.96%) and third generation (53.01%).
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Affiliation(s)
- Tong Ming Liu
- State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, China
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49
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Abstract
The technique of nuclear transfer (NT) allows the production of embryos, fetuses, and offspring from a range of embryonic, fetal, and adult derived cell types in a range of species. Successful development is dependent upon numerous factors, including type of recipient cell, source of recipient cell, method of reconstruction, activation, embryo culture, donor cell type, and donor and recipient cell cycle stages. The present review will discuss the uses of NT, the techniques presently available, and the factors affecting subsequent development.
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Affiliation(s)
- K H Campbell
- School of Biosciences, University of Nottingham, Leicestershire, United Kingdom.
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50
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Kawahara M, Mori T, Tanaka H, Shimizu H. The suppression of fragmentation by stabilization of actin filament in porcine enucleated oocytes. Theriogenology 2002; 58:1081-95. [PMID: 12240912 DOI: 10.1016/s0093-691x(02)00939-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A thorough understanding of the mechanism underlying fragmentation would contribute to the improvement of the developmental ability of reconstructed embryos after nuclear transfer. We conducted the present study to elucidate the influence of the nuclear transfer method on fragmentation of enucleated oocytes and the relationship between change in actin filament distribution and fragmentation. In Experiment 1, we examined activation rates of in vitro matured oocytes. These were 12.9% in maturation alone, 75.7% in electrical stimulation, and 57.9% in ethanol/cycloheximide treatment. In Experiment 2, we observed a higher rate of fragmentation (P < 0.05) in cultured oocytes that had been enucleated and electrically stimulated than in oocytes subjected to the other treatments (maturation alone, enucleation alone and enucleation plus ethanol/cycloheximide activation). In Experiment 3, we stained enucleated and electrically stimulated oocytes with rhodamine/phalloidin dye to show discontinuous distributions in the ooplasm of treated oocytes; oocytes in the other treatment groups showed homogenous distributions of actin filaments (AFs). In Experiment 4, we added cytochalasin B, an inhibitor of AF polymerization, to the culture medium, which prevented fragmentation of enucleated plus electrically stimulated oocytes (cytochalasin B, [+] 0.0%, [-] 60.7% at 24 h after treatment, P < 0.05). In Experiment 5, we investigated the relationship between fragmentation and alteration in AF distribution in enucleated plus electrically stimulated oocytes. At 0 h of culture, enucleated plus electrically stimulated oocytes showed discontinuous distributions of AFs, while nontreated oocytes showed homogenous AF distributions. At 24 and 48 h of culture, fragmentation proceeded in enucleated plus electrically stimulated oocytes and the discontinuous AF distribution diminished with time. In Experiment 6, we added hyaluronic acid (HA) to the culture medium, which suppressed fragmentation of enucleated plus electrically stimulated oocytes (HA, [+] 28.5%, [-] 66.4% at 24 h after treatment, P < 0.05). The results suggest that electrical stimulation induces a change in the AF distribution of oocytes, resulting in fragmentation, and that the addition of HA to the culture media is effective for the suppression of fragmentation.
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Affiliation(s)
- Manabu Kawahara
- Laboratory of Animal Breeding and Reproduction, Graduate School of Agriculture, Hokkaido University, Sapporo-shi, Japan
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