242 HIGHLY EFFICIENT SLEEPING BEAUTY TRANSPOSON-MEDIATED TRANSGENESIS IN BOVINE FETAL FIBROBLASTS

2016 ◽  
Vol 28 (2) ◽  
pp. 253
Author(s):  
A. E. Fili ◽  
A. P. Alessio ◽  
W. Garrels ◽  
D. O. Forcato ◽  
M. F. Olmos Nicotra ◽  
...  
Keyword(s):  
Cell Lines ◽  
Nuclear Transfer ◽  
Fluorescent Protein ◽  
Sleeping Beauty ◽  
Expression Cassette ◽  
Pcr Analysis ◽  
Helper Plasmid ◽  
Fetal Fibroblasts ◽  
Genomic Insertions

Active transposon-mediated transgenesis is an emerging tool for basic and applied research in livestock. We have demonstrated the effectiveness of a helper-independent piggyBac transposon (pGENIE-3) for gene transfer into the genome of bovine cells (Alessio et al. 2014 Reprod. Domest. Anim. 49, 8). Here, we extend our previous research by examining the suitability of a Sleeping Beauty (SB) transposon-based methodology to deliver transgenes into the genome of bovine fetal fibroblasts (BFF), and the ability of these cells to support in vitro embryo development upon somatic cell nuclear transfer (SCNT). In a first experiment, BFF were chemically cotransfected (JetPRIME®, Polyplus-transfection, Illkirch, France) with a helper plasmid (pCMV-SB100X), which carries an expression cassette for the SB transposase, and the donor vector (pT2/Venus/RMCE) harboring an expression cassette for a fluorescent protein (Venus) flanked by the SB inverted terminal repeats (ITR). Three different ratios of helper and donor plasmids were studied: 1 : 2, 1 : 1 and 2 : 1. After 15 days of culture, the number of fluorescent colonies was counted on an inverted microscope. When vectors were used at ratios of 1 : 1 and 2 : 1, a 78-fold and 88-fold increase (P ≤ 0.05) in the number of fluorescent colonies compared with that in the no-transposase control were calculated. In a second experiment, BFF were chemically cotransfected with the helper vector pCMV-SB100X, and 2 donor transposons: pT2/Venus/RMCE and pT2/SV40-Neo. The former harbors a neo resistance cassette framed by SB ITRs. Different ratios of helper:donors (1 : 1 : 1, 2 : 1 : 1 and 2 : 0.5 : 0.5) were studied, and each ratio compared with a no-transposase control. After 15 days of antibiotic selection, the number of G418-resistant colonies was determined. Every time a functional SB transposase vector was included, the number of fluorescent and G418-resistant colonies was markedly higher compared with that in the respective control without transposase (P ≤ 0.001). Interestingly, all G418-resistant colonies expressed Venus. Molecular characterisation of genomic insertions in 6 monoclonal cell lines was performed by PCR and splinkerette PCR. PCR analysis confirmed presence of the Venus transgene in all cell lines. Splinkerette PCR results revealed at least 15 transposase-catalyzed genomic insertions of the transgene. Individual cells from a polyclonal SB transgenic fibroblast culture were used as nuclear donors to produce zona-free SCNT embryos. Of the reconstructed embryos, 33% reached blastocyst stage and about half of them expressed Venus. In conclusion, SB transposase is able to actively transpose monomeric copies of transgenes into the genome of bovine cells, which can be reprogrammed upon nuclear transfer to generate morphologically normal embryos expressing the transgene of interest.

Development and spindle formation in rat somatic cell nuclear transfer (SCNT) embryos in vitro using porcine recipient oocytes

Zygote ◽  
2009 ◽  
Vol 17 (3) ◽  
pp. 195-202 ◽  
Author(s):  
Atsushi Sugawara ◽  
Satoshi Sugimura ◽  
Yumi Hoshino ◽  
Eimei Sato
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Fluorescent Protein ◽  
Cumulus Cells ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Spindle Formation ◽  
Fetal Fibroblasts

SummaryCloning that uses somatic cell nuclear transfer (SCNT) technology with gene targeting could be a potential alternative approach to obtain valuable rat models. In the present study, we determined the developmental competence of rat SCNT embryos constructed using murine and porcine oocytes at metaphase II (MII). Further, we assessed the effects of certain factors, such as: (i) the donor cell type (fetal fibroblasts or cumulus cells); and (ii) premature chromosome condensation (PCC) with normal spindle formation, on the developmental competence of rat interspecies SCNT (iSCNT) embryos. iSCNT embryos that had been constructed using porcine oocytes developed to the blastocyst stage, while those embryos made using murine MII oocytes did not. Rat iSCNT embryos constructed with green fluorescent protein (GFP)-expressing fetal fibroblasts injected into porcine oocytes showed considerable PCC with a normal bipolar spindle formation. The total cell number of iSCNT blastocyst derived from GFP-expressing fetal fibroblasts was higher than the number derived from cumulus cells. In addition, these embryos expressed GFP at the blastocyst stage. This paper is the first report to show that rat SCNT embryos constructed using porcine MII oocytes have the potential to develop to the blastocyst stage in vitro. Thus the iSCNT technique, when performed using porcine MII oocytes, could provide a new bioassay system for the evaluatation of the developmental competence of rat somatic cells.

In vitro development of green fluorescent protein (GFP) transgenic bovine embryos after nuclear transfer using different cell cycles and passages of fetal fibroblasts

2000 ◽  
Vol 12 (2) ◽  
pp. 1 ◽  
Author(s):  
Sangho Roh ◽  
Hosup Shim ◽  
Woo-suk Hwang ◽  
Jong-taek Yoon
Keyword(s):  
Green Fluorescent Protein ◽  
Nuclear Transfer ◽  
Fluorescent Protein ◽  
Blastocyst Formation ◽  
In Vitro Development ◽  
Donor Cells ◽  
Fetal Fibroblasts ◽  
Green Fluorescent ◽  
Vitro Development

Nuclear transfer using transfected donor cells provides an efficient new strategy for the production of transgenic farm animals. The present study assessed in vitro development of nuclear transfer embryos using green fluorescent protein (GFP) gene-transfected bovine fetal fibroblasts. In experiment 1, bovine fetal fibroblasts (BFF) were transfected with linearized pEGFP-N1 by electroporation, and the enucleated oocytes were reconstructed by nuclear transfer of transfected cells (BFF-GFP). The rates of blastocyst formation did not differ significantly between BFF and BFF-GFP (18.2% v. 15.6%). In experiment 2, before nuclear transfer, the donor cell stage was synchronized by serum deprivation or forming a confluent monolayer. The rates of cleavage (67.1% v. 71.8%) and blastocyst formation (15.8% v. 15.5%) did not differ between confluent and serum-starved cells after nuclear transfer. In experiment 3, the effects of different passages of donor fibroblast cells on the development of nuclear transfer embryos were investigated. Donor cells from ‘early’ (at passage 8–16) showed better blastocyst development (18.9%) than those from ‘late’ (at passage 17–32; 10.5%). In conclusion, this study suggests that transgenic somatic cell nuclei from early passages can be reprogrammed more effectively than those from late passages. In addition, GFP, a non-invasive selection marker, can be used to select transgenic nuclear transfer embryos.

Inhibition of GSTpi Activity Increases the Sensitivity of MCL Cell Lines to Cisplatin, Cytarabin and Bortezomib, but Not Doxorubicin.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2806-2806
Author(s):  
Aurelie Paret ◽  
Delphine Rolland ◽  
Vincent Ribrag ◽  
Bertrand Coiffier ◽  
Catherine Thieblemont
Keyword(s):  
Cell Lines ◽  
Nuclear Transfer ◽  
Agaricus Bisporus ◽  
Pcr Analysis ◽  
Rt Pcr ◽  
Aberrant Expression ◽  
Cytotoxic Effects ◽  
Mantle Cell ◽  
Broad Variety

Abstract Preliminary data suggest drug resistance plays a major role in mantle cell lymphoma (MCL) and is linked to the aberrant expression of molecules such as Glutathion S-Transferase pi (GST pi) that catalyzes the nuclear conjugation of a broad variety of reactive electrophiles to the glutathion. We investigated in vitro the effect of the inhibition of GSTpi activity on the chemosensitivity of MCL cell lines by inhibiting the nuclear transport of GSTpi with Agaricus bisporus leptine (ABL). Methods. Four MCL cell lines (Granta, NCEB, REC and UPN1) were analyzed for GSTP1 transcript expression by RT-PCR analysis and for GSTP1 genetic Ile105Val polymorphism. The effect of ABL on the 4 MCL cell lines viability was examined using cells pre-treated with ABL (40μg/ml) for 10 h followed by treatment with various concentrations of doxorubicin (DOX), cisplatin (CDDP), cytarabin and bortezomib for 48 h. The cell viability was estimated by MTT assay repeated three times. Results. All the 4 cell lines expressed GSTPI transcript. Two of them (UPN1 and REC) were heterozygous for Ile105Val polymorphism, whereas NCEB and GRANTA were homozygous GSTP1-105Ile which has been correlated with an enzyme of high activity. DOX, CDDP, cytarabin and bortezomib have cytotoxic effects compared to non-treated cells, without any difference between the 4 MCL cell lines when considering their genetic polymorphism status. Co-administration of ABL caused a significant increasis of the cytotoxicity of CDDP and bortezomib in all cell lines (Student test: p between 0.0004 to 0.02 for CDDP; and p between 0.013 and 0.05 for velcade, depending on the cell lines). Co-administration of ABL caused an increasis of the cytotoxicity of cytarabin in 3 cell lines, the 4th being actually tested. No influence of ABL was detected on the cytotoxic effect of DOX. The analysis of the nuclear and the cytoplasmic localizations of GSTpi is currently realized by immunohistochemistry. Conclusion. These results suggest that inhibition of the nuclear transfer of GSTpi increases in vitro the MCL sensitivity to CDDP, cytarabin and velcade but not DOX.

299 DEVELOPMENTAL COMPETENCE OF TRANSGENIC BOVINE EMBRYOS RECONSTRUCTED BY NUCLEAR TRANSFER USING MEIOSIS-BLOCKED OOCYTES

2008 ◽  
Vol 20 (1) ◽  
pp. 229
Author(s):  
F. F. Bressan ◽  
M. Miranda ◽  
P. R. Adona ◽  
T. H. C. De Bem ◽  
F. V. Meirelles ◽  
...  
Keyword(s):  
In Vitro Culture ◽  
Oocyte Maturation ◽  
Nuclear Transfer ◽  
Fluorescent Protein ◽  
Calf Serum ◽  
Developmental Competence ◽  
Green Fluorescent Protein Gene ◽  
Fetal Fibroblasts ◽  
Parthenogenetic Embryos

Recent progress in animal cloning by nuclear transfer (NT) has made it feasible to produce transgenic animals using genetically modified cell lines. Healthy cells and competent oocytes are needed to maximize the number of transgenic calves produced. Oocyte maturation plays a central role in oocyte competence. Prematuration inducing meiosis block is, therefore, a possible tool in transgenesis, because it allows further optimization of oocyte maturation protocols. In field conditions, it is not always possible to precisely control timing between oocyte collection and NT procedures. Therefore, temporarily and reversibly blocking maturation may also be used as a strategy to optimize cloning protocols. The aim of this study was to analyze the developmental competence of embryos reconstructed by NT using cells modified genetically as nuclei donors and oocytes submitted, or not, to meiosis block as cytoplasts. The hypothesis was that blocking meiosis does not alter the embryonic developmental physiology nor production of transgenic cloned bovine blastocysts. Ovaries were collected at a slaughterhouse and follicles between 3 and 6 mm were aspirated. Oocytes were divided into 2 groups. The first group (CTR, n = 145) was matured in vitro (IVM) with TCM-199 supplemented with 10% fetal calf serum, 5.0 µg mL–1 of LH, 0.5 µg mL–1 of FSH, 0.2 mm pyruvate, and 10 µg mL–1 of gentamicin for 18 h at 38.5�C under 5% CO2 in a humidified atmosphere. The second group (BL, n = 153) had meiosis blocked by in vitro culture with TCM-199 supplemented with 0.2 mm pyruvate, 10 µg mL–1 of gentamicin, and 10 µm butyrolactone I for 24 h, and then matured in vitro for 18 h. Parthenogenetic embryos resulted from meiosis-blocked and non-blocked oocytes were used as controls for the respective groups of NT embryos. After IVM, oocytes from both groups were reconstructed using bovine fetal fibroblasts transduced previously with a lentivirus and expressing the green fluorescent protein gene. The effect of treatment on fusion rates in cloned embryos, cleavage rates on Day 2, and blastocyst rates on Day 7 of in vitro culture of cloned and parthenogenetic embryos from CTR and BL groups were analyzed by chi-square test at 5% significance. Meiosis block did not affect fusion rates (n = 68, 46.90% and n = 86, 56.21% for CTR and BL cloned groups, respectively). Cleavage rates did not differ between cloned groups (n = 43, 63.24% and n = 49, 56.98% for CTR and BL groups) or between parthenogenetic groups (n = 15, 50% and n = 21, 70% for CTR and BL groups). Also, no difference was observed in blastocyst rates between cloned groups (n = 5, 7.35% and n = 6, 6.98% for CTR and BL groups) and between parthenogenetic groups (n = 11, 36.67% and n = 9, 30% for CTR and BL groups). It was concluded that meiosis block does not affect embryo development to the blastocyst stage. It is suggested that temporarily blocking meiosis may be a useful strategy to optimize NT protocols. FAPESP, Brazil.

Production of transgenic canine embryos using interspecies somatic cell nuclear transfer

Zygote ◽  
2011 ◽  
Vol 20 (1) ◽  
pp. 67-72 ◽  
Author(s):  
So Gun Hong ◽  
Hyun Ju Oh ◽  
Jung Eun Park ◽  
Min Jung Kim ◽  
Geon A. Kim ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Fluorescent Protein ◽  
Somatic Cells ◽  
Embryonic Stem ◽  
Transfected Cells ◽  
Fetal Fibroblasts ◽  
Transgenic Cells

SummarySomatic cell nuclear transfer (SCNT) has emerged as an important tool for producing transgenic animals and deriving transgenic embryonic stem cells. The process of SCNT involves fusion of in vitro matured oocytes with somatic cells to make embryos that are transgenic when the nuclear donor somatic cells carry ‘foreign’ DNA and are clones when all the donor cells are genetically identical. However, in canines, it is difficult to obtain enough mature oocytes for successful SCNT due to the very low efficiency of in vitro oocyte maturation in this species that hinders canine transgenic cloning. One solution is to use oocytes from a different species or even a different genus, such as bovine oocytes, that can be matured easily in vitro. Accordingly, the aim of this study was: (1) to establish a canine fetal fibroblast line transfected with the green fluorescent protein (GFP) gene; and (2) to investigate in vitro embryonic development of canine cloned embryos derived from transgenic and non-transgenic cell lines using bovine in vitro matured oocytes. Canine fetal fibroblasts were transfected with constructs containing the GFP and puromycin resistance genes using FuGENE 6®. Viability levels of these cells were determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. Interspecies SCNT (iSCNT) embryos from normal or transfected cells were produced and cultured in vitro. The MTT measurement of GFP-transfected fetal fibroblasts (mean OD = 0.25) was not significantly different from non-transfected fetal fibroblasts (mean OD = 0.35). There was no difference between transgenic iSCNT versus non-transgenic iSCNT embryos in terms of fusion rates (73.1% and 75.7%, respectively), cleavage rates (69.7% vs. 73.8%) and development to the 8–16-cell stage (40.1% vs. 42.7%). Embryos derived from the transfected cells completely expressed GFP at the 2-cell, 4-cell, and 8–16-cell stages without mosaicism. In summary, our results demonstrated that, following successful isolation of canine transgenic cells, iSCNT embryos developed to early pre-implantation stages in vitro, showing stable GFP expression. These canine–bovine iSCNT embryos can be used for further in vitro analysis of canine transgenic cells and will contribute to the production of various transgenic dogs for use as specific human disease models.

scholarly journals 145COMBINED GLUCOSE AND FRUCTOSE SUPPLEMENTATION IN PROTEIN-FREE KSOM IMPROVES PREIMPLANTATION DEVELOPMENT OF BOVINE TRANSGENIC CLONED EMBRYOS

2004 ◽  
Vol 16 (2) ◽  
pp. 194 ◽  
Author(s):  
M.M.U. Bhuiyan ◽  
G. Jang ◽  
E.-S. Park ◽  
K.-H. Ko ◽  
H.-Y. Jeon ◽  
...  
Keyword(s):  
Embryo Development ◽  
Nuclear Transfer ◽  
Fluorescent Protein ◽  
Total Concentration ◽  
Chemical Activation ◽  
Marker Gene ◽  
Donor Cell ◽  
Preimplantation Development ◽  
Fetal Fibroblasts

The present study investigated the effect of fructose supplementation in protein-free potassium simplex optimization medium (KSOM) on the preimplantation development of bovine transgenic cloned embryos. An expression plasmid containing bovine mutant PrP gene and enhanced green fluorescent protein (eGFP) as a marker gene was constructed and transfected into bovine fetal fibroblasts using FuGene6 (Roche, Indianapolis, IN, USA) as a lipid carrier. Transfected cells were cultured for 5 to 6 days to achieve chromosomal integration of the gene and then used for nuclear transfer. The somatic cell nuclear transfer was carried out by transferring a GFP-expressing donor cell into the perivitelline space of an enucleated oocyte. After electrical fusion and chemical activation, 525 (11 replicates) fused embryos were cultured in KSOM supplemented with 0.01% (w/v) PVA for 192 h at 39°C under 5% CO2, 5% O2 and 90% N2 gas atmosphere. The embryos were randomly allocated for 4 culture groups; KSOM supplemented with 1) 0.2mM glucose, 2) 1.5mM fructose, 3) 0.2mM glucose+1.5mM fructose and 4) vehicle (without glucose and fructose). We used 0.2mM glucose as per formulation of KSOM (Biggers JD et al. 2000 Biol. Reprod. 63, 281–293) and 1.5mM fructose due to its benefical effect on embryo development (Kwun J et al. 2003 Mol. Reprod. Dev. 65, 167–174). As a control experiment, 1043 (17 replicates) in vitro fertilized (IVF) embryos were cultured in the same culture system. The data were analyzed by PROC-GLM using SAS program. In IVF embryos, no significant differences in rates of cleavage (71.7 to 75.5%), morulae (34.1 to 37.1%) and blastocysts formation (21.0 to 24.5%) among the culture groups were observed. In contrast, significantly (P<0.05) higher rate in blastocysts formation (19.2%) was obtained when transgenic cloned embryos were cultured in KSOM supplemented with 0.2mM glucose+1.5mM fructose than with 0.2mM glucose (10.0%). However, the differences in blastocysts formation rates among other culture groups (13.2% for 1.5mM fructose and 11.9% for vehicle) were not significant. Moreover, the rates of cleavage (76.2 to 79.1%), morulae (19.3 to 23.8%) and GFP expression in blastocysts (68.0 to 78.6%) did not differ significantly among the culture groups for transgenic cloned embryos. This study demonstrated that the requirement of energy substrates in culture medium for bovine transgenic cloned and IVF embryos might be different. Now, we are conducting experiments to confirm whether the beneficial effect on transgenic cloned embryo development is due to combined effect of glucose and fructose or due to total concentration of available energy. This study was supported by Biogreen 21-1000520030100000.

Blocking Pleiotrophin Activity Inhibits Multiple Myeloma (MM) Cell Growth In Vitro and in a Severe Combined Immunodeficient (SCID)-hu Murine Model of Human MM.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 114-114
Author(s):  
Richard A. Campbell ◽  
Haiming Chen ◽  
Hee Jin Lee ◽  
Howard S. Yeh ◽  
Melinda S. Gordon ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Growth ◽  
Tumor Growth ◽  
Cell Lines ◽  
Murine Model ◽  
Fluorescent Protein ◽  
Pcr Analysis ◽  
Mouse Serum

Abstract Pleiotrophin (PTN) is a heparin-binding growth factor that binds CD138 and stimulates angiogenesis, tumor growth and metastasis in some solid tumors. Recently, we have shown that this factor is highly produced by multiple myeloma (MM) cell lines including RPMI8226 and U266 and fresh malignant plasma cells, and is secreted into the culture medium following short-term culture of bone marrow from MM patients. We investigated the effects of PTN on MM growth in vitro and in vivo using a SCID-hu murine MM model. We determined the anti-proliferative effects of suppressing PTN by cloning a whole PTN sense or anti-sense cDNA construct containing the green fluorescent protein (GFP) gene into the MM cell lines RPMI8226 and U266. Cells transduced with sense PTN showed markedly increased proliferation compared to cells transduced with vector alone whereas the anti-sense-containing MM cells showed reduced cell numbers. In addition, we treated RPMI8226 and U266 cells with a polyclonal anti-PTN antibody and evaluated its effect on MM growth. These cells were cultured for 48 hours in the presence of the anti-PTN antibody at a concentration of 100 micrograms/ml or a control antibody, and effects on cell growth assessed with an MTT assay. Marked anti-MM effects were observed with the anti-PTN antibody compared to the control antibody in both cell lines [RPMI8226 (p < 0.01) and U266 (p < 0.001)]. In order to further define the importance of PTN in the growth of MM in a more clinically relevant in vivo setting, we determined whether this polyclonal anti-PTN antibody could suppress tumor growth and human paraprotein secretion using our SCID-hu murine model of human myeloma LAGλ-1. LAGλ-1 has been previously shown by our group to produce large amounts of PTN as measured in mouse serum by ELISA and by RT- PCR analysis on freshly isolated LAGλ-1 tumor cells. Thirty SCID mice (n = 5 mice/group) were implanted with a 0.4 – 0.6 cm3 LAGλ-1 tumor fragment into the left hind limb muscle. Fourteen days following implantation, mice were randomized into treatment groups, and received treatment intraperitoneally (IP) with anti-PTN antibody at doses of 0.1, 0.3, 1.0, 3.0 or 10 mg/kg or vehicle alone twice weekly. Mice receiving anti-PTN antibody at the highest doses (3.0 and 10 mg/kg) showed marked inhibition of tumor growth [3.0 mg/kg (p < 0.03), 10 mg/kg (p < 0.008)] as well as decreases in levels of human paraprotein [3.0 mg/kg (p < 0.004), 10 mg/kg (p < 0.003)]. Notably, immunohistochemical staining with an anti-CD138 antibody showed a marked reduction in cells with CD138 positivity in the LAGλ-1 tumors from animals treated with anti-PTN antibody compared to mice treated with vehicle alone. These in vitro and in vivo results demonstrate that PTN may be a potential new target for the treatment of MM. The effects of this therapy on angiogenesis and cell signaling are currently under investigation.

scholarly journals Development and Characterization of a cDNA-Launch Recombinant Simian Hemorrhagic Fever Virus Expressing Enhanced Green Fluorescent Protein: ORF 2b’ Is Not Required for In Vitro Virus Replication

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 632
Author(s):  
Yingyun Cai ◽  
Shuiqing Yu ◽  
Ying Fang ◽  
Laura Bollinger ◽  
Yanhua Li ◽  
...  
Keyword(s):  
Green Fluorescent Protein ◽  
Cell Lines ◽  
Enhanced Green Fluorescent Protein ◽  
Fluorescent Protein ◽  
Infectious Clone ◽  
Hemorrhagic Fever ◽  
Simian Hemorrhagic Fever Virus ◽  
Hemorrhagic Fever Virus ◽  
Green Fluorescent

Simian hemorrhagic fever virus (SHFV) causes acute, lethal disease in macaques. We developed a single-plasmid cDNA-launch infectious clone of SHFV (rSHFV) and modified the clone to rescue an enhanced green fluorescent protein-expressing rSHFV-eGFP that can be used for rapid and quantitative detection of infection. SHFV has a narrow cell tropism in vitro, with only the grivet MA-104 cell line and a few other grivet cell lines being susceptible to virion entry and permissive to infection. Using rSHFV-eGFP, we demonstrate that one cricetid rodent cell line and three ape cell lines also fully support SHFV replication, whereas 55 human cell lines, 11 bat cell lines, and three rodent cells do not. Interestingly, some human and other mammalian cell lines apparently resistant to SHFV infection are permissive after transfection with the rSHFV-eGFP cDNA-launch plasmid. To further demonstrate the investigative potential of the infectious clone system, we introduced stop codons into eight viral open reading frames (ORFs). This approach suggested that at least one ORF, ORF 2b’, is dispensable for SHFV in vitro replication. Our proof-of-principle experiments indicated that rSHFV-eGFP is a useful tool for illuminating the understudied molecular biology of SHFV.

scholarly journals 34 LIFESPAN AND CHROMOSOMAL STABILITY OF BOVINE AND PORCINE FETAL FIBROBLAST CELLS CULTURED IN VITRO

2005 ◽  
Vol 17 (2) ◽  
pp. 167 ◽  
Author(s):  
A.M. Giraldo ◽  
J.W. Lynn ◽  
C.E. Pope ◽  
R.A. Godke ◽  
K.R. Bondioli
Keyword(s):  
Cell Lines ◽  
Cultured Cells ◽  
Culture Conditions ◽  
Cycle Duration ◽  
Fibroblast Cells ◽  
Proliferative Capacity ◽  
Chromosomal Stability ◽  
Fetal Fibroblasts ◽  
Fetal Bovine

The low efficiency of nuclear transfer (NT) has been related to factors such as mitochondria heteroplasmy, failure of genomic activation, and asynchrony between the donor karyoplast and recipient cytoplast. Few studies have characterized donor cell lines in terms of proliferative capacity and chromosomal stability. It is known that suboptimal culture conditions can induce chromosomal abnormalities, and the use of aneuploid donor cells during NT can lead to a high incidence of abnormal cloned embryos (Giraldo et al. 2004 Reprod. Fertil. Dev. 16, 124 abst). The purpose of this study was to determine the lifespan and chromosomal stability of bovine and porcine fetal cells. Four bovine and four porcine fibroblast cells lines were established from 50-day and 40-day fetuses, respectively. Cells were cultured in DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin and streptomycin at 37°C in 5% CO2. Each cell line was passaged to senescence. Total population doublings (PDs) and cell cycle duration were calculated. To determine the chromosome numbers at different PDs, cells were synchronized in metaphase, fixed, and stained. ANOVA and chi-square tests were used to analyze differences in PDs and proportion of aneuploid cells between cell lines, respectively (P < 0.05). The results show that proliferative capacity was not different between cell lines derived from the same species. Cell lines derived from bovine and porcine fetuses had different in vitro lifespans (33 PDs vs. 42 PDs, respectively; P < 0.05). The mean length of the cell cycles for both bovine and porcine fetal fibroblasts was ∼28 h. The percentage of aneupliod cells in both bovine and porcine fetal cell lines increased progressively with duration of culture (see Table) and was high throughout the study. The proliferative capacity of cultured cells was similar within individuals of the same species, but growth characteristics differed between fetal bovine and porcine cell lines. The progressive increase of aneuploid cells could be due to suboptimal culture conditions or unusual chromosome instability in the particular fetuses used. These data demonstrate the importance of determining chromosome content and the use of cells at early passages to decrease the percentage of aneuploid reconstructed embryos and increase the efficiency of NT.

scholarly journals 63 IMPROVED IN VITRO DEVELOPMENT OF PORCINE EMBRYOS PRODUCED BY NUCLEAR TRANSFER, IVF AND PARTHENOGENESIS

2005 ◽  
Vol 17 (2) ◽  
pp. 181 ◽  
Author(s):  
D. Sage ◽  
P. Hassel ◽  
B. Petersen ◽  
W. Mysegades ◽  
P. Westermann ◽  
...  
Keyword(s):  
Nuclear Transfer ◽  
Culture Media ◽  
Cumulus Cells ◽  
Cell Number ◽  
Foster Mother ◽  
Chi Square ◽  
Fetal Fibroblasts ◽  
Blastocyst Rate ◽  
Parthenogenetic Embryos

Porcine nuclear transfer (NT) is an inefficient process and it is necessary to use as many as 120 NT embryos for each foster mother to obtain small litters of live piglets. In these experiments, we evaluated the effects of culture atmosphere and medium on the development of NT embryos by monitoring blastocyst rate and cell number of Day 6 blastocysts. Age matched IVF and parthenogenetic embryos were also evaluated for comparison. For all experiments a pool of oocytes was aspirated from ovaries collected in a local abattoir. Following aspiration, oocytes were allowed to mature for 40 h in North Carolina State University (NCSU)-37 medium (supplemented with cAMP and hCG/eCG for the first 22 h). After removal of the cumulus cells, denuded oocytes with polar bodies were selected for NT, enucleated, fused with fetal fibroblasts, and sequentially activated electrically and chemically by 3 h of treatment with 6-dimethylaminopurine (6-DMAP). A second group of oocytes from the same denuded pool were maintained in TL-HEPES medium and activated in parallel with the NT group to produce parthenogenetic embryos. A third group was fertilized with frozen-thawed epididymal semen and co-cultured for ∼12 h to give IVF embryos. All three treatment groups were subdivided into a control subgroup and an experimental subgroup. In the first experiment, we compared the effects of atmosphere (20% vs. 5% oxygen) on in vitro embryonic development in NCSU-23 medium. In the second experiment, we used only the 5% oxygen concentration and compared different culture media. One subgroup was maintained in standard NCSU-23 medium and the second subgroup was cultured in a two-step system for the first 58 h in modified NCSU-23 (without glucose but supplemented with 2.0 mM lactate and 0.2 mM pyruvate), followed by addition of glucose to give a final concentration of 5.55 mM. Data were statistically analyzed by analysis of variance and chi square test. Blastocyst rate and mean cell number in all three embryo groups were improved under 5% oxygen. The most dramatic effect was observed in the NT group, in which the blastocyst rate increased significantly (P < 0.001) from 6.7% ± 5.9 (n = 279) to 19.6% ± 8.9 (n = 250) and mean cell number increased from 17.7 ± 12.1 to 25.8 ± 10.3 cells per blastocyst. With 5% oxygen there was also an increase of blastocyst rates and mean cell numbers in both IVF and parthenogenetic groups. In the second experiment, blastocyst rate for NT embryos increased significantly (P < 0.05) from 21.8% ± 7.6 (n = 242) in conventional NCSU-23 to 31.5% ± 11.0 (n = 271) in the modified system whereas there was almost no difference in the mean cell number of both groups (29.2 ± 4.3 vs. 31.5 ± 5.3). In the groups of IVF and parthenogenetic embryos no difference was found. These results indicate that both the reduced oxygen and the modified culture medium are important for pre-implantation development of porcine nuclear transfer embryos.

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