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1.
PLoS One ; 18(1): e0278607, 2023.
Article in English | MEDLINE | ID: mdl-36696395

ABSTRACT

Here we report urine-derived cell (UDC) culture and subsequent use for cloning which resulted in the successful development of cloned canine pups, which have remained healthy into adulthood. Bovine UDCs were used in vitro to establish comparative differences between cell sources. UDCs were chosen as a readily available and noninvasive source for obtaining cells. We analyzed the viability of cells stored in urine over time and could consistently culture cells which had remained in urine for 48hrs. Cells were shown to be viable and capable of being transfected with plasmids. Although primarily of epithelial origin, cells were found from multiple lineages, indicating that they enter the urine from more than one source. Held in urine, at 4°C, the majority of cells maintained their membrane integrity for several days. When compared to in vitro fertilization (IVF) derived embryos or those from traditional SCNT, UDC derived embryos did not differ in total cell number or in the number of DNA breaks, measured by TUNEL stain. These results indicate that viable cells can be obtained from multiple species' urine, capable of being used to produce live offspring at a comparable rate to other cell sources, evidenced by a 25% pregnancy rate and 2 live births with no losses in the canine UDC cloning trial. This represents a noninvasive means to recover the breeding capacity of genetically important or infertile animals. Obtaining cells in this way may provide source material for human and animal studies where cells are utilized.


Subject(s)
Cloning, Organism , Live Birth , Animals , Dogs , Female , Pregnancy , Cloning, Organism/methods , Cloning, Organism/veterinary , Live Birth/veterinary , Pregnancy Rate , Urine/cytology
2.
Sci Rep ; 12(1): 11209, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35778582

ABSTRACT

Animal cloning has been popularized for more than two decades, since the birth of Dolly the Sheep 25 years ago in 1996. There has been an apparent waning of interest in cloning, evident by a reduced number of reports. Over 1500 dogs, representing approximately 20% of the American Kennel Club's recognized breeds, have now been cloned, making the dog (Canis familiaris) one of the most successfully cloned mammals. Dogs have a unique relationship with humans, dating to prehistory, and a high degree of genome homology to humans. A number of phenotypic variations, rarely recorded in natural reproduction have been observed in in these more than 1000 clones. These observations differ between donors and their clones, and between clones from the same donor, indicating a non-genetic effect. These differences cannot be fully explained by current understandings but point to epigenetic and cellular reprograming effects of somatic cell nuclear transfer. Notably, some phenotypic variations have been reversed through further cloning. Here we summarize these observations and elaborate on the cloning procedure.


Subject(s)
Cloning, Organism , Nuclear Transfer Techniques , Animals , Cloning, Organism/methods , Dogs , Genome , Mammals , Nuclear Transfer Techniques/veterinary , Sheep
3.
Front Vet Sci ; 9: 872383, 2022.
Article in English | MEDLINE | ID: mdl-35685340

ABSTRACT

The umbilical cord acts as the critical lifeline of the developing fetus by providing nutrients and oxygen to it. Umbilical cord abnormalities are considered the leading cause of stillbirth in humans, but information on stillbirths associated with umbilical cord abnormalities is very scant in the clinical practice of animals. Here, we described a case of fetal demise in camels indicated to be caused by fetal death from strangulation by its umbilical cord, which is commonly known as the nuchal cord. A pregnant camel at its 36 weeks of gestation spontaneously aborted a single fetus. The camel was 5 years old and nullipara. A 6-day-old cloned embryo was transferred transcervically to the recipient. Pregnancy was confirmed 50 days after embryo transfer by ultrasonography, and the pregnant camel was maintained under a standard nutritional plan. The neck of the aborted fetus was strangulated tightly by a double loop of the umbilical cord. There was no congenital anomaly or other malformation in the fetus. We concluded that the nuchal cord was tightly coiled around the neck of the fetus and interfered with the blood flow in the fetus by collapsing the umbilical vein and subsequently causing fetal death and abortion. To the authors' knowledge, this is the first reported case of a nuchal cord in camels.

4.
Zygote ; 30(4): 522-527, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35357293

ABSTRACT

We compared the pregnancy and live birth rates following transfer of early-stage embryos or blastocysts produced by somatic cell nuclear transfer using in vitro-matured oocytes. In total 102 ovaries were collected from dromedary camels at a local abattoir; from these 1048 cumulus-oocytes complexes (COCs) were aspirated and cultured for 42 h in a commercial maturation medium. Metaphase II oocytes were subjected to nuclear transfer. Somatic cell nuclear transfer-derived embryos were cultured in a commercial embryo medium for 2 or 7 days. Next, 71 early-stage embryos were surgically transferred to the left fallopian tube of 28 recipients and 47 blastocysts were transferred to the left uterine horn of 26 recipients. Early pregnancy was detected by serum progesterone (P4), and pregnancy was confirmed using ultrasonography on days 30 and 90 after embryo transfer. Pregnancy rate based on P4 level was 17.86% (5/28) and 11.54% (3/26) for early-stage embryo and blastocyst transfer, respectively. In the early-stage embryo group, out of five recipients, one recipient had lost the pregnancy by the first ultrasonography on day 30; two other recipients aborted at 14 and 24 weeks, and two recipients gave live births. In the blastocyst group, out of three recipients, one lost the pregnancy at an early stage and two recipients gave live births. Therefore, for dromedary camels, we recommend transvaginal blastocyst transfer from the standpoint of the pregnancy and live birth rate, ease of the transfer procedure, and comfort and safety of the recipients.


Subject(s)
Camelus , Embryo Culture Techniques , Animals , Blastocyst , Embryo Culture Techniques/methods , Embryo Transfer , Female , Oocytes , Pregnancy , Pregnancy Rate
5.
Anim Reprod Sci ; 233: 106842, 2021 Sep 08.
Article in English | MEDLINE | ID: mdl-34530180

ABSTRACT

The embryonic stage, site of embryo transfer in the reproductive tract of the surrogate, and embryo transfer method are important for the successful production of offspring. In the present study, there was comparison of pregnancy rates in camels following the surgical transfer of early-developmental stage embryos at Day 2 and transvaginal transfer of blastocysts at Day 7. Embryos were produced by somatic cell nuclear transfer using in vivo-matured oocytes and ear fibroblasts as donor cells. A total of 305 oocytes were collected from 27 donors, among which 275 oocytes were in metaphase II. In Group A, 110 oocytes were reconstructed, 78 fused oocytes were cultured for 2 days, and 37 early-developmental stage embryos were transferred into 13 surrogates. In Group B, 165 oocytes were utilized, 117 fused oocytes were cultured for 7 days, and 24 blastocysts were trans-vaginally transferred into 12 surrogates. Pregnancy was determined when there was an increase in serum progesterone concentrations and was confirmed using real-time ultrasonography. Microsatellite analysis was performed to confirm the parentage of offspring. Two live births occurred in Groups A and B (live birth rate of 15.4% and 16.7%, respectively). Results indicate both early-developmental stage embryos and blastocysts produced by somatic cell nuclear transfer using in vivo-matured oocytes can lead to live births in camel with similar efficiency. It, therefore, is recommended that trans-vaginal blastocyst transfer be utilized for camels considering the pregnancy and live birth rates, ease of the transfer procedure and comfort and safety of surrogates.

6.
PLoS One ; 15(6): e0233784, 2020.
Article in English | MEDLINE | ID: mdl-32492024

ABSTRACT

Recent advances in somatic cell nuclear transfer (SCNT) in canines facilitate the production of canine transgenic models. Owing to the importance of stable and strong promoter activity in transgenic animals, we tested human elongation factor 1α (hEF1α) and cytomegalovirus (CMV) promoter sequences in SCNT transgenic dogs. After transfection, transgenic donor fibroblasts with the hEF1α-enhanced green fluorescence protein (EGFP) transgene were successfully isolated using fluorescence-activated cell sorting (FACS). We obtained four puppies, after SCNT, and identified three puppies as being transgenic using PCR analysis. Unexpectedly, EGFP regulated by hEF1α promoter was not observed at the organismal and cellular levels in these transgenic dogs. EGFP expression was rescued by the inhibition of DNA methyltransferases, implying that the hEF1α promoter is silenced by DNA methylation. Next, donor cells with CMV-EGFP transgene were successfully established and SCNT was performed. Three puppies of six born puppies were confirmed to be transgenic. Unlike hEF1α-regulated EGFP, CMV-regulated EGFP was strongly detectable at both the organismal and cellular levels in all transgenic dogs, even after 19 months. In conclusion, our study suggests that the CMV promoter is more suitable, than the hEF1α promoter, for stable transgene expression in SCNT-derived transgenic canine model.


Subject(s)
Cloning, Organism/veterinary , Cytomegalovirus/genetics , Nuclear Transfer Techniques/veterinary , Peptide Elongation Factor 1/genetics , Promoter Regions, Genetic/genetics , Transcriptional Activation/genetics , Animals , Animals, Genetically Modified , Azacitidine/pharmacology , Cells, Cultured , DNA (Cytosine-5-)-Methyltransferases/antagonists & inhibitors , DNA Methylation/drug effects , Dogs , Embryo Transfer/veterinary , Female , Fibroblasts/metabolism , Gene Expression Regulation/drug effects , Green Fluorescent Proteins/genetics , Humans , Pregnancy , Transfection , Transgenes
7.
PLoS One ; 12(8): e0182973, 2017.
Article in English | MEDLINE | ID: mdl-28827814

ABSTRACT

Tumor barrier function in carcinoma represents a major challenge to treatment and is therefore an attractive target for increasing drug delivery. Variables related to tumor barrier include aberrant blood vessels, high interstitial fluid pressure, and the composition and structure of the extracellular matrix. One of the proteins associated with dense extracellular matrices is fibromodulin, a collagen fibrillogenesis modulator expressed in tumor stroma but scarce in normal loose connective tissues. Here, we investigated the effects of fibromodulin on stroma ECM in a syngeneic murine colon carcinoma model. We show that fibromodulin deficiency decreased collagen fibril thickness but glycosaminoglycan content and composition were unchanged. Furthermore, vascular density, pericyte coverage and macrophage amount were unaffected. Fibromodulin can therefore be a unique effector of dense collagen matrix assembly in tumor stroma and, without affecting other major matrix components or the cellular composition, can function as a main agent in tumor barrier function.


Subject(s)
Collagen/metabolism , Colonic Neoplasms/metabolism , Disease Models, Animal , Fibromodulin/deficiency , Glycosaminoglycans/metabolism , Animals , Cell Line, Tumor , Colonic Neoplasms/pathology , Fibromodulin/genetics , Mice , Mice, Inbred C57BL
8.
J Transl Med ; 15(1): 47, 2017 02 23.
Article in English | MEDLINE | ID: mdl-28231806

ABSTRACT

BACKGROUND: Imatinib causes increased turnover of stromal collagen, reduces collagen fibril diameter, enhances extracellular fluid turnover and lowers interstitial fluid pressure (IFP) in the human colonic carcinoma KAT-4/HT-29 (KAT-4) xenograft model. METHODS: We compared the effects of imatinib on oxygen levels, vascular morphology and IFP in three experimental tumor models differing in their content of a collagenous extracellular matrix. RESULTS: Neither the KAT4 and CT-26 colonic carcinoma models, nor B16BB melanoma expressed PDGF ß-receptors in the malignant cells. KAT-4 tumors exhibited a well-developed ECM in contrast to the other two model systems. The collagen content was substantially higher in KAT-4 than in CT-26, while collagen was not detectable in B16BB tumors. The pO2 was on average 5.4, 13.9 and 19.3 mmHg in KAT-4, CT-26 and B16BB tumors, respectively. Treatment with imatinib resulted in similar pO2-levels in all three tumor models but only in KAT-4 tumors did the increase reach statistical significance. It is likely that after imatinib treatment the increase in pO2 in KAT-4 tumors is caused by increased blood flow due to reduced vascular resistance. This notion is supported by the significant reduction observed in IFP in KAT-4 tumors after imatinib treatment. Vessel area varied between 4.5 and 7% in the three tumor models and was not affected by imatinib treatment. Imatinib had no effect on the fraction of proliferating cells, whereas the fraction of apoptotic cells increased to a similar degree in all three tumor models. CONCLUSION: Our data suggest that the effects of imatinib on pO2-levels depend on a well-developed ECM and provide further support to the suggestion that imatinib acts by causing interstitial stroma cells to produce a less dense ECM, which would in turn allow for an increased blood flow. The potential of imatinib treatment to render solid tumors more accessible to conventional treatments would therefore depend on the degree of tumor desmoplasia.


Subject(s)
Colonic Neoplasms/metabolism , Extracellular Matrix/metabolism , Imatinib Mesylate/pharmacology , Neoplasms, Experimental/metabolism , Oxygen/pharmacology , Animals , Apoptosis/drug effects , Cell Line, Tumor , Collagen/metabolism , Colonic Neoplasms/blood supply , Colonic Neoplasms/pathology , Extracellular Fluid/drug effects , Extracellular Fluid/metabolism , Extracellular Matrix/drug effects , Mice, SCID , Neoplasms, Experimental/blood supply , Neoplasms, Experimental/pathology , Pressure , Receptor, Platelet-Derived Growth Factor beta/metabolism , Stromal Cells/metabolism , Tumor Burden/drug effects , Water
9.
Mol Cancer Ther ; 15(10): 2455-2464, 2016 10.
Article in English | MEDLINE | ID: mdl-27474147

ABSTRACT

A typical obstacle to cancer therapy is the limited distribution of low molecular weight anticancer drugs within the carcinoma tissue. In experimental carcinoma, imatinib (STI571) increases efficacy of synchronized chemotherapy, reduces tumor interstitial fluid pressure, and increases interstitial fluid volume. STI571 also increases the water-perfusable fraction in metastases from human colorectal adenocarcinomas. Because the mechanism(s) behind these effects have not been fully elucidated, we investigated the hypothesis that STI571 alters specific properties of the stromal extracellular matrix. We analyzed STI571-treated human colorectal KAT-4/HT-29 experimental carcinomas, known to have a well-developed stromal compartment, for solute exchange and glycosaminoglycan content, as well as collagen content, structure, and synthesis. MRI of STI571-treated KAT-4/HT-29 experimental carcinomas showed a significantly increased efficacy in dynamic exchanges of solutes between tumor interstitium and blood. This effect was paralleled by a distinct change of the stromal collagen network architecture, manifested by a decreased average collagen fibril diameter, and increased collagen turnover. The glycosaminoglycan content was unchanged. Furthermore, the apparent effects on the stromal cellular composition were limited to a reduction in an NG2-positive stromal cell population. The current data support the hypothesis that the collagen network architecture influences the dynamic exchanges of solutes between blood and carcinoma tissue. It is conceivable that STI571 reprograms distinct nonvascular stromal cells to produce a looser extracellular matrix, ultimately improving transport characteristics for traditional chemotherapeutic agents. Mol Cancer Ther; 15(10); 2455-64. ©2016 AACR.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma/metabolism , Collagen/metabolism , Extracellular Fluid/metabolism , Imatinib Mesylate/pharmacology , Protein Aggregates , Protein Kinase Inhibitors/pharmacology , Animals , Carcinoma/drug therapy , Carcinoma/pathology , Cell Line, Tumor , Disease Models, Animal , Endothelial Cells/metabolism , Female , Humans , Immunohistochemistry , Mice , Pericytes/drug effects , Pericytes/metabolism , Stromal Cells/metabolism , Xenograft Model Antitumor Assays
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