• Journal of Korean Neurosurgical Society
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• v.42 no.2
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• pp.118-124
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• 2007

Objective : Adipose tissue is derived from the embryonic mesoderm and contains a heterogenous stromal cell population. Authors have tried to verify the characteristics of stem cell of adipose derived stromal cells (ADSCs) and to investigate immunohistochemical findings after transplantation of ADSC into rat brain to evaluate survival, migration and differentiation of transplanted stromal cells. Methods : First ADSCs were isolated from human adipose tissue and induced adipose, osseous and neuronal differentiation under appropriate culture condition in vitro and examined phenotypes profile of human ADSCs in undifferentiated states using flow cytometry and immunohistochemical study. Human ADSCs were transplanted into the healthy rat brain to investigate survival, migration and differentiation after 4 weeks. Results : From human adipose tissue, adipose stem cells were harvested and subcultured for several times. The cultured ADSCs were differentiated into adipocytes, osteoctye and neuron-like cell under conditioned media. Flow cytometric analysis of undifferentiated ADSCs revealed that ADSCs were positive for CD29, CD44 and negative for CD34, CD45, CD117 and HLA-DR. Transplanted human ADSCs were found mainly in cortex adjacent to injection site and migrated from injection site at a distance of at least 1 mm along the cortex and corpus callosum. A few transplanted cells have differentiated into neuron and astrocyte. Conclusion : ADSCs were differentiated into multilineage cell lines through transdifferentiation. ADSCs were survived and migrated in xenograft without immunosuppression. Based on this data, ADSCs may be potential source of stem cells for many human disease including neurologic disorder.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.751-760
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• 2018

BACKGROUND: Bone tissue engineering based on pluripotent stem cells (PSCs) is a new approach to deal with bone defects. Protocols have been developed to generate osteoblasts from PSCs. However, the low efficiency of this process is still an important issue that needs to be resolved. Many studies have aimed to improve efficiency, but developing accurate methods to determine efficacy is also critical. Studies using pluripotency to estimate efficacy are rare. Telomerase is highly associated with pluripotency. METHODS: We have described a quantitative method to measure telomerase activity, telomeric repeat elongation assay based on quartz crystal microbalance (QCM). To investigate whether this method could be used to determine the efficiency of in vitro osteogenic differentiation based on pluripotency, we measured the pluripotency pattern of cultures through stemness gene expression, proliferation ability and telomerase activity, measured by QCM. RESULTS: We showed that the pluripotency pattern determined by QCM was similar to the patterns of proliferation ability and gene expression, which showed a slight upregulation at the late stages, within the context of the general downregulation tendency during differentiation. Additionally, a comprehensive gene expression pattern covering nearly every stage of differentiation was identified. CONCLUSION: Therefore, this assay may be powerful tools for determining the efficiency of differentiation systems based on pluripotency. In this study, we not only introduce a new method for determining efficiency based on pluripotency, but also provide more information about the characteristics of osteogenic differentiation which help facilitate future development of more efficient protocols.

• Journal of Life Science
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• v.19 no.5
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• pp.587-592
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• 2009

A dramatic morphological change of embryos occurs at peri-implantation. Maternal and embryonic cross-talk during this period, initiated by signals from embryo(s), provides signals for maternal recognition of pregnancy and establishing and maintaining the pregnancy. However, the cellular, biochemical and genetic processes that direct embryo remodeling in mammalian species are not well studied or understood. In order to identify potential genes responsible for morphological change and cross-talk between embryo and uterus, an initial EST analysis was performed. A catalog of expressed genes (Transcriptome) from the d12 peri-implanting porcine embryos was constructed. Six clones were chosen from the initial ESTs for elucidation of their expression patterns during embryogenesis in early pregnancy. A number of these genes demonstrated unique expression profiles in a tissue, cell-type, and temporal fashion, indicating dynamic regulation of embryonic and endometrial gene expressions at different stages of pregnancy. Cross-talk between the embryo and endometrium of the pregnant uterus has provided a suitable micro-environment for the embryo's rapid and dramatic morphological changing process at the peri-implantation stage.

• Journal of Embryo Transfer
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• v.23 no.3
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• pp.133-139
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• 2008

DNA methylation is one of the reasons for poor survival of clone animals. The OCT-4 gene is essential for maintaining pluripotency of embryonic stem (ES) cells and early embryos. We previously reported that the 5'-promoter region of Oct-4 gene was a target of DNA methylation and the methylation status was changed variously during embryonic development in bovine. The study conducted to examine the expression and methylation pattern of tissue-dependent differentially methylated region (T-DMR) of Oct-4 gene in bovine somatic cell nuclear transfer (SCNT) and in vitro fertilization (IVF) blastocysts. The Oct-4 gene expression was evaluated by RT-PCR and fluorescence immunocytochemistry. The methylation pattern of T-DMR was analyzed using restriction mapping and bisulfite sequencing methods. The Oct-4 transcripts were highly expressed in IVF, while they were not expressed in SCNT. The Oct-4 protein was not detected or expressed at very low level in SCNT, the intensity of Oct-4 protein, however, was strong in IVF. On the other hand, the T-DMR of Oct-4 gene was hypermethylated in SCNT compared to that of IVF. These results suggested that expression and the failure of demethylation of Oct-4 gene was closely associated with incomplete development of SCNT embryos.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.7-8
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• 2003

Since it was first reported in 1997, somatic cell cloning has been demonstrated in several other mammalian species. On the mouse, it can be cloned from embryonic stem (ES) cells, fetus-derived cells, and adult-derived cells, both male and female. While cloning efficiencies range from 0 to 20%, rates of just 1-2% are typical (i.e. one or two live offspring per one hundred initial embryos). Recently, abnormalities in mice cloned from somatic cells have been reported, such as abnormal gene expression in embryo (Boiani et al., 2001, Bortvin et al., 2003), abnormal placenta (Wakayama and Yanagimachi 1999), obesity (Tamashiro et ai, 2000, 2002) or early death (Ogonuki et al., 2002). Such abnormalities notwithstanding, success in generating cloned offspring has opened new avenues of investigation and provides a valuable tool that basic research scientists have employed to study complex processes such as genomic reprogramming, imprinting and embryonic development. On the other hand, mouse ES cell lines can also be generated from adult somatic cells via nuclear transfer. These 'ntES cells' are capable of differentiation into an extensive variety of cell types in vitro, as well assperm and oocytes in vivo. Interestingly, the establish rate of ntES cell line from cloned blastocyst is much higher than the success rate of cloned mouse. It is also possible to make cloned mice from ntES cell nuclei as donor, but this serial nuclear transfer method could not improved the cloning efficiency. Might be ntES cell has both character between ES cell and somatic cell. A number of potential agricultural and clinical applications are also are being explored, including the reproductive cloning of farm animals and therapeutic cloning for human cell, tissue, and organ replacement. This talk seeks to describe both the relationship between nucleus donor cell type and cloning success rate, and methods for establishing ntES cell lines. (중략)

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.16-18
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• 2004

This study was carried out to analyze the amount of telomeres and telomerase activity of several chicken cells. Telomere quantity and telomerase activity were analyzed during organ development, growth and aging in embryonic and adults chicken. Analyzed cells were whole embryos and the cells from brain, heart, liver, kidney, lymphocytes and germinal tissues in Korean Native Chicken. The amount of telomeric DNA was analyzed by quantitative fluorescence in situ hybridization (Q-FISH) techniques using a chicken telomere repeat probe. Telomerase activity was performed by Telomeric Repeat Amplification Protocol (TRAP) assay. In results, telomerase activity was highly detectable in early embryonic cells, germinal cells and kidney cells. Whereas the cells from brain, heart, and liver had gradually down-regulated pattern of telomerase activity. Analyzing the telomere quantities on chicken cells, the amount of telomeric DNA of most chicken cells gradually decreased as growth. From these results, the amount of telomeric DNA was directly affected by telomerase activity. Consequently the telomere quantity and telomerase activity are closely relate to cell differentiation and tissue specificity during developmental and growing stages.

• The Korean Journal of Pain
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• v.32 no.4
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• pp.245-255
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• 2019

Stem cells are attracting attention as a key element in future medicine, satisfying the desire to live a healthier life with the possibility that they can regenerate tissue damaged or degenerated by disease or aging. Stem cells are defined as undifferentiated cells that have the ability to replicate and differentiate themselves into various tissues cells. Stem cells, commonly encountered in clinical or preclinical stages, are largely classified into embryonic, adult, and induced pluripotent stem cells. Recently, stem cell transplantation has been frequently applied to the treatment of pain as an alternative or promising approach for the treatment of severe osteoarthritis, neuropathic pain, and intractable musculoskeletal pain which do not respond to conventional medicine. The main idea of applying stem cells to neuropathic pain is based on the ability of stem cells to release neurotrophic factors, along with providing a cellular source for replacing the injured neural cells, making them ideal candidates for modulating and possibly reversing intractable neuropathic pain. Even though various differentiation capacities of stem cells are reported, there is not enough knowledge and technique to control the differentiation into desired tissues in vivo. Even though the use of stem cells is still in the very early stages of clinical use and raises complicated ethical problems, the future of stem cells therapies is very bright with the help of accumulating evidence and technology.

• Animal Bioscience
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• v.36 no.2
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• pp.175-190
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• 2023

Objective: The study was conducted to screen differentially expressed long noncoding RNA (lncRNA) in chickens by high-throughput sequencing and explore its mechanism of action on intramuscular fat deposition. Methods: Herein, Rose crown and Cbb broiler chicken embryo breast and leg muscle lncRNA and mRNA expression profiles were constructed by RNA sequencing. A total of 96 and 42 differentially expressed lncRNAs were obtained in Rose crown vs Cobb broiler chicken breast and leg muscle, respectively. lncRNA-ENSGALT00000046546, with high interspecific variability and a potential regulatory role in lipid metabolism, and its predicted downstream target gene 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2), were selected for further study on the preadipocytes. Results: lncRNA-46546 overexpression in chicken preadipocyte 2 cells significantly increased (p<0.01) the expression levels of AGPAT2 and its downstream genes diacylglycerol acyltransferase 1 and diacylglycerol acyltransferase 2 and those of the fat metabolism-related genes peroxisome proliferator-activated receptor γ, CCAAT/enhancer binding protein α, fatty acid synthase, sterol regulatory element-binding transcription factor 1, and fatty acid binding protein 4. The lipid droplet concentration was higher in the overexpression group than in the control cells, and the triglyceride content in cells and medium was also significantly increased (p<0.01). Conclusion: This study preliminarily concludes that lncRNA-46546 may promote intramuscular fat deposition in chickens, laying a foundation for the study of lncRNAs in chicken early embryonic development and fat deposition.

• Development and Reproduction
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• v.6 no.1
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• pp.55-66
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• 2002

Embryonic stem cells(ES cells) are derived from the inner cell mass(ICM) of blastocysts, which have the potentials to remain undifferentiated, to proliferate indefinitely in vitro, to differentiate into the derivates of three embryonic germ layers. ES cells are an attractive model system for studying the initial developmental decisions and their molecular mechanisms during embryogenesis. Additionally, ES cells of significant interest to those characterizing the various gene functions utilizing transgenic and gene targeting techniques. We investigated the effects of reproductive hormones, gonadotropins(GTH) and steroids on the induction of differentiation and expressions of their receptor genes using the newly established mouse ES cells. We collected the matured blastocysts of inbred mice C57BL/6J after superovulation and co-cultured with mitotically inactivated STO feeder cells. After 5 passages, we confirmed the expression alkaline phosphatase(Alk P) activity and SSEA-1, 3, 4 expressions. The protocol devised for inducing ES differentiation consisted of an aggregation steps, after 5 days as EBs in hormone treatments(FSH, LH, E$_2$, P$_4$, T) that allows complex signaling to occur between the cells and a dissociation step, induced differentiation through attachment culture during 7 days in hormone treatments. Hormone receptors were not increased in dose-dependent manner. All hormone receptors in ES cells treated reproductive hormones were expressed lower than those of undifferentiated ES cell except for LHR expression in E$_2$-treated ES cells group. After hormone induced differentiation, at least some of the cells are not terminally differentiated, as is evident from the expression of Oct-4, a marker of undifferentiated. To assess their differentiation by gene expression, we analyzed the expression of 7 tissue-specific markers from all three germ layers. Most of hormone-treated group increased in the expression of gata-4 and $\alpha$ -fetoprotein, suggesting reproductive hormone allowed or induced differentiation of endoderm.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.186-189
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• 1998

Malignant mesenchymoma is a very rare tumor presented during the embryonic and infant period and malignant mesenchymoma in the adult is extremely rare. Tumor is composed of two or more unrelated mesenchymal derivatives apart from fibrous tissue. These tumors are thought to be originated from embryonic mesenchyme capable of differentiating into any type of connective tissue. A 61 years old man with complaints of cough and copious sputum of onset of two months was admitted after initial examinations, showing a very huge mass over the right upper lobe. Right pneumonectomy with partial rib resection of 3rd, 4th, and 5th ribs was performed due to the initial diagnostic impression of squamous cell carcinoma by the fine needle aspiration biopsy. The operative field presented a mass locating across the interlobal fissure with severe adhesions to the chest wall. Postoperatively, the patient received 5,000 rads of radiotherapy and presently, 6 months later, has shown no signs of recurrence.