scholarly journals The Effects of Donor Cell Type and Culture Medium on in vitro Development of Domestic Cat Embryos Reconstructed by Nuclear Transplantation

2001 ◽  
Vol 14 (8) ◽  
pp. 1057-1061 ◽  
Author(s):  
Mokhamad Fahrudin ◽  
Takeshige Otoi ◽  
Ni Wayan Kurniani Karja ◽  
Masako Murakami ◽  
Tatsuyuki Suzuki
2004 ◽  
Vol 16 (2) ◽  
pp. 202 ◽  
Author(s):  
W.F. Swanson ◽  
A.L. Manharth ◽  
J.B. Bond ◽  
H.L. Bateman ◽  
R.L. Krisher ◽  
...  

Domestic cat embryos typically are cultured in media formulated for somatic cells or embryos from rodents or livestock species. Under these conditions, blastocyst development has been inconsistent and delayed relative to embryos grown in vivo, and embryo viability following transfer has been low. Our goal is to systematically define the culture requirements of the feline embryo to improve embryo development and viability. The objective of this study was to determine the ionic (NaCl, KCl, KH2PO4, and CaCl2:MgSO4) preferences of domestic cat IVF embryos. Anestral female cats were injected (i.m.) with 150IU eCG followed 84h later by 100IUhCG. Oocytes were recovered via laparoscopic follicular aspiration approximately 24h post-hCG injection (Day 0). Semen was collected from one of two males by means of an artificial vagina and washed once in HEPES-buffered IVF medium. Mature cumulus-oocyte complexes were co-incubated with 2.5–5×105 motile sperm mL−1 in IVF medium (100mM NaCl, 4.0mM KCl, 1.0mM KH2 PO4, 2.0mM CaCl2, 1.0mM MgSO4-7H2O, 25.0mM NaHCO3, 3.0mM glucose, 0.1mM pyruvate, 6.0mM L-lactate, 1.0mM glutamine, 0.1mM taurine, 1×MEM nonessential amino acids, 50μgmL−1 gentamicin, and 4.0mgmL−1 BSA) for 19 to 22h in 6% CO2 in air (38.7°C). Cumulus cells were removed and embryos cultured (8–11 embryos/50μL drop; 6% CO2, 5% O2, 89% N2, 38.7°C) in media containing 100.0 or 120.0mM NaCl, 4.0 or 8.0mM KCl, 0.25 or 1.0mM KH2PO4, and 1.0mM:2.0mM or 2.0mM:1.0mM CaCl2:MgSO4 (2×2×2×2 factorial design). The remaining components of the culture medium were identical to the IVF medium (but w/o gentamicin). Development to the blastocyst stage by Day 6, metabolism (glycolysis and pyruvate) of each blastocyst, and final cell number (Hoechst 33342 staining) of all embryos were evaluated. Final cell number of cleaved embryos and development to the blastocyst stage were analyzed using analysis of variance in the GLIMMIX macro of SAS. A total of 236 oocytes were inseminated, yielding 128 cleaved embryos (54%), including 6 blastocysts (4.7% of cleaved embryos). Cell number was not (P>0.05) affected by NaCl, KCl, or KH2PO4 concentrations, but tended (P=0.057) to be higher after culture in 2.0mM:1.0mM CaCl2:MgSO4. Treatments did not significantly affect (P>0.05) development to the blastocyst stage, but numerically more blastocysts were produced in 100.0mM NaCl (4/6), 8.0mM KCl (5/6), or 1.0mM KH2PO4 (5/6). Both CaCl2:MgSO4 ratios resulted in 3 blastocysts. Blastocysts contained 61.08±5.1 (mean±SEM, n=6) cells and actively metabolized glucose (glycolysis, 3.7±0.8pmol/embryo/3h or 0.06±0.01pmol/cell/3h) and pyruvate (0.75±0.27pmol/embryo/3h or 0.013±0.005pmol/cell/3h). These results suggest that the ionic composition of culture media influences the in vitro development of cat IVF embryos. (Supported by NIH grant RR15388.)


2012 ◽  
Vol 14 (2) ◽  
pp. 146-154 ◽  
Author(s):  
Naresh L. Selokar ◽  
Monika Saini ◽  
Mushariffa Muzaffer ◽  
G. Krishnakanth ◽  
Ambika P. Saha ◽  
...  

2011 ◽  
Vol 23 (1) ◽  
pp. 142
Author(s):  
J. Galiguis ◽  
M. C. Gómez ◽  
C. E. Pope ◽  
B. L. Dresser ◽  
S. P. Leibo

Although considerable progress has been made in the development of successful methods for cryopreservation of embryos, oocytes are much less cryotolerant. There appears to be an inverse relationship between cryosurvival and intracellular lipid levels. For example, cat oocytes, which appear microscopically as coffee-coloured, nearly opaque spheres due to their high lipid content, are extremely sensitive to cryopreservation. Oocyte delipidation thus represents a potential approach to improving cryosurvival. The objectives of the present study were to examine 1) the effects of calcium (Ca2+, 0 v. 10 nM), FBS (0 v. 10%), and cytochalasin B (CB, 7.5 v. 20.0 μg mL–1) during mechanical delipidation by high-speed centrifugation on in vitro development of IVM cat oocytes, and 2) the influence of centrifugation, degree of lipid polarization (partial v. full), and co-culture with cat fetal fibroblasts (CFF) on in vitro development of vitrified IVM cat oocytes. In Experiment 1, oocytes were randomly allocated to each centrifugation medium and centrifuged at 12 000 × g for 20 min. Oocytes were then fertilized with epididymal sperm (motile sperm mL–1) and cultured until Day 8 (Pope et al. 2006 Theriogenology 66, 59–71). In Experiment 2, oocytes were centrifuged with the optimal centrifugation medium obtained in experiment 1, allocated to each treatment and vitrified in a solution of 15% DMSO, 15% ethylene glycol, and 18% sucrose (2008 Reprod. Fertil. Dev. 20, 188). Liquified oocytes were fertilized and cultured until Day 8. In both experiments, cleavage and degeneration rates were determined on Day 2 and blastocyst development on Day 8. Data were analysed by 2-way ANOVA and chi-square tests. In Experiment 1, of 939 oocytes that were centrifuged and fertilized, 40% of those treated in 0 nM Ca2+ cleaved and 22% developed into blastocysts, v. 33 and 6%, respectively, in 10 nM Ca2+ (P < 0.05). The respective cleavage and degeneration frequencies for oocytes treated in 10% FBS were 43 and 19% v. 19 and 3% in 0% FBS (P < 0.05). Cleavage and blastocyst development after treatment with 7.5 and 20.0 μg mL–1 CB were 36 and 15% v. 42 and 22%, respectively. In Experiment 2, 493 oocytes were vitrified/liquified and fertilized. The degeneration, cleavage, and blastocyst rates of non-centrifuged oocytes were 49, 21, and 0% v. 31 (P < 0.05), 38 (P < 0.05), and 7%, respectively, of centrifuged oocytes. Of centrifuged oocytes with partially extruded lipids, 34% degenerated, 34% cleaved, and 4% developed into blastocysts v. 29, 42, and 10%, respectively, of oocytes with fully extruded lipids. Degeneration, cleavage and blastocyst rates of co-cultured v. control oocytes were 18, 36, and 10%, v. 26 (P < 0.05), 34, and 3%, respectively. In summary, cryotolerance of domestic cat oocytes to vitrification was 1) affected by their lipid content, and 2) improved by mechanical reduction of intracellular lipids. When oocytes were fully delipidated in Ca2+-free medium containing 10% FBS and 20.0 μg mL–1 CB before vitrification and co-cultured after IVF with CFF, blastocyst development was similar to that of control, non-vitrified oocytes.


2015 ◽  
Vol 124 ◽  
pp. 76-80 ◽  
Author(s):  
Yi Min Wang ◽  
Xiang Bin Ding ◽  
Xin Feng Liu ◽  
Yong Zhang

2017 ◽  
Author(s):  
◽  
Bethany Rae Mordhorst

Gene edited pigs serve as excellent models for biomedicine and agriculture. Currently, the most efficient way to make a reliably-edited transgenic animal is through somatic cell nuclear transfer (SCNT) also known as cloning. This process involves using cells from a donor (which may have been gene edited) that are typically grown in culture and using their nuclear content to reconstruct a new zygote. To do this, the cell may be placed in the perivitelline space of an enucleated oocyte and activated artificially by a calcium-containing media and electrical pulse waves. While it is remarkable that this process works, it is highly inefficient. In pigs the success of transferred embryos becoming live born piglets is only 1-3%. The creation of more cloned pigs enables further study for the benefit of both A) biomedicine in the development of prognosis and treatments and B) agriculture, whether it be for disease resistance, feed efficiency, gas emissions, etc. Two decades of research has not drastically improved the cloning efficiency of most mammals. One of the main impediments to successful cloning is thought to be due to inefficient nuclear reprogramming and remodeling of the donor cell nucleus. In the following chapters we detail our efforts to improve nuclear reprogramming of porcine fetal fibroblasts by altering the metabolism to be more blastomere-like in nature. We used two methods to alter metabolism 1) pharmaceutical agents and 2) hypoxia. After treating donor cells both methods were used in nuclear transfer. Pharmaceutical agents did not improve in vitro development of gestational survival of clones. Hypoxia did improve in vitro development and we are currently awaiting results of gestation.


2015 ◽  
Vol 27 (1) ◽  
pp. 131 ◽  
Author(s):  
J. H. Galiguis ◽  
C. E. Pope ◽  
M. N. Biancardi ◽  
C. Dumas ◽  
G. Wang ◽  
...  

Vitrification remains a promising technique in the preservation of valuable genetic material; however, in the cat, success has varied. Live kittens have been produced from embryos vitrified at early cleavage stages, but phenotypic abnormalities in some kittens suggest possible epigenetic effects of the vitrification process. It has been reported that cryopreservation alters epigenetic events in somatic donor cells, which indirectly influences physical status of cloned offspring. However, extending post-warming in vitro culture of donor cells corrects these epigenetic modifications, resulting in normal embryos/clones. Accordingly, in the present study, vitrification was performed at the pronuclear stage to lengthen pretransfer culture time, and vitrified cat zygotes were assessed by analysing (1) histone acetylation/methylation, (2) global DNA methylation, (3) pluripotent gene expression, (4) in vitro development, and () in vivo viability. In vivo matured/IVF oocytes were vitrified in 15% dimethyl sulfoxide, 15% ethylene glycol, and 0.5 M sucrose at 16 h post-insemination (PI). After warming in 1.0 M sucrose at 38°C, embryos were fixed at 18 h or 40 h PI, and the nuclear intensity of either acetyl/dimethyl-H3K9 or 5-methylcytosine was determined by immunofluorescence. Results showed that at 18 h PI, mean H3K9ac intensity of vitrified embryos (11.8; n = 6) was higher than that of corresponding nonvitrified (fresh) controls (4.5; n = 6) and the fresh (3.2; n = 11) and vitrified (0.6; n = 7) 40-h groups (2-way ANOVA; P < 0.05). H3K9me2 in the fresh (36.9) and vitrified (32.5) 18-h embryos was similar but increased relative to both fresh (10.7) and vitrified (9.2) 40-h groups (P < 0.05). Mean DNA methylation (5MeC) in the fresh (31.6; n = 1) and vitrified (24.7; n = 3) 18-h groups was similar to that of the fresh 40-h group (19.8; n = 4) but higher than that of the vitrified 40-h group (15.0; n = 5; P < 0.05). To assess expression of POU5F1 and Nanog, qRT-PCR was performed on Day 8 blastocysts. Relative to controls (n = 9), mean POU5F1 and Nanog levels in vitrified blastocysts (n = 24) were 1.38- and 1.98-fold higher, respectively (one-way ANOVA; P > 0.05). In terms of in vitro development, Day 2 cleavage of vitrified zygotes (59%; n = 508) was similar to that of controls (66%; n = 340), but Day 8 blastocyst formation was reduced (9 v. 31%; t-test; P < 0.05). In vivo viability was assessed by oviducal transfer of 41 Day 1 embryos into 2 recipients. One pregnancy was established (50%), with 3 live kittens weighing 70, 79, and 131 g delivered without assistance on Day 65 of gestation. The 2 smaller kittens died within a few hours of birth, with the smallest exhibiting an umbilical hernia and organ exteriorization. The third kitten developed into a normal, healthy adult. In summary, mean H3K9me2, 5MeC, and POU5F1/Nanog expression of vitrified zygotes was similar to corresponding controls. H3K9ac increased at 18h PI as a result of vitrification, but was reduced after culture to 40 h PI. Although vitrified zygotes cleaved in vitro at rates similar to controls, blastocyst development was reduced. In vivo viability was demonstrated; however, postnatal survival of kittens produced was low.


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