• BMB Reports
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• 제52권12호
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• pp.689-694
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• 2019

Ethical and safety issues have rendered mesenchymal stem cells (MSCs) popular candidates in regenerative medicine, but their therapeutic capacity is lower than that of induced pluripotent stem cells (iPSCs). This study compared original, dental tissue-derived MSCs with re-differentiated MSCs from iPSCs (iPS-MSCs). CD marker expression in iPS-MSCs was similar to original MSCs. iPS-MSCs expressed higher in pluripotent genes, but lower levels in mesodermal genes than MSCs. In addition, iPS-MSCs did not form teratomas. All iPSCs carried mtDNA mutations; some shared with original MSCs and others not previously detected therein. Shared mutations were synonymous, while novel mutations were non-synonymous or located on RNA-encoding genes. iPS-MSCs also harbored mtDNA mutations transmitted from iPSCs. Selected iPS-MSCs displayed lower mitochondrial respiration than original MSCs. In conclusion, screening for mtDNA mutations in iPSC lines for iPS-MSCs can identify mutation-free cell lines for therapeutic applications.

• BMB Reports
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• 제41권10호
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• pp.699-704
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• 2008

Embryonic stem (ES) cell-derived cardiomyocytes (ESCMs) must be specifically purified in order to prevent teratoma formation, and this confusing issue has hampered their clinical application. We therefore investigated a technique to generate pure labeled ESCMs for possible use in cardiac repair. We generated transgenic ES cell lines expressing enhanced green fluorescent protein (EGFP) under the transcriptional control of the $\alpha$-cardiac myosin heavy chain ($\alpha$-MHC) promoter. Differentiated EGFP-positive ES cells displayed characteristics of CMs. Furthermore, neuregulin-1 (NRG-1) upregulated the expression of the cardiac-restricted transcription factors Nkx2.5 and GATA-4, as well as differentiated CM factors ($\alpha$-MHC, $\beta$-MHC). Immunohistochemistry demonstrated that NRG-1 increased expression of cardiac-specific troponin T in the beating foci of the embryoid bodies. This work revealed a potential method for specifically labeling and enriching ESCMs by combining genetically-engineered ES cell clones and exogenous growth factor treatment.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2002년도 춘계학술발표대회 발표논문초록집
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• pp.22-22
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• 2002

Identification of spermatogonial stern cell-specific surface molecules is important in understanding the molecular mechanisms underlying the maintenance and differentiation of these cells. We have found that spermatogonia from busulfan treated mice expressed an autoantigen that distinguishes between undifferentiated and differentiated spermatogonia. Four to six weeks after busulfan treatment, germ cells located in the basal compartment of seminiferous epithelium show isotype-specific IgG deposits that form due to autoimmunity. (omitted)

• Journal of Plant Biology
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• 제38권3호
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• pp.281-288
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• 1995

The progressive differentiation of interfascicular cambium from residual meristem in the first internode of Ginkgo biloba seedlings was elucidated by light and electron microscopy. The cells of residual meristem were small and homogeneous and heterogeneous in their arrangement but those of the adjacent cortex and pith were large and homogeneous. Some interprocambial residual meristem progressively became elongated and vacuolated during the process of the differentiation. In tangential section, residual meristem composed of long and short cells. The eventual interfascicular cambium had long fusiform initials and short ray initials. Storage materials in the cells progressively disappeared from the interprocambial residual meristem and were absent in early interfascicular cambium. Both the radial and tangential walls of cells of the interprocambial residual meristem were almost the same, but the radial wall became progressively thicker than the tangential wall during differentiation of interfascicular cambium. From these results, it is clear that interfascicular cambium is gradually differentiated from residual meristem.

• IMMUNE NETWORK
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• 제14권1호
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• pp.54-65
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• 2014

Bone marrow-derived mesenchymal stem cells (MSCs) are multipotent, with the ability to differentiate into different cell types. Additionally, the immunomodulatory activity of MSCs can downregulate inflammatory responses. The use of MSCs to repair injured tissues and treat inflammation, including in neuroimmune diseases, has been extensively explored. Although MSCs have emerged as a promising resource for the treatment of neuroimmune diseases, attempts to define the molecular properties of MSCs have been limited by the heterogeneity of MSC populations. We recently developed a new method, the subfractionation culturing method, to isolate homogeneous human clonal MSCs (hcMSCs). The hcMSCs were able to differentiate into fat, cartilage, bone, neuroglia, and liver cell types. In this study, to better understand the properties of neurally differentiated MSCs, gene expression in highly homogeneous hcMSCs was analyzed. Neural differentiation of hcMSCs was induced for 14 days. Thereafter, RNA and genomic DNA was isolated and subjected to microarray analysis and DNA methylation array analysis, respectively. We correlated the transcriptome of hcMSCs during neural differentiation with the DNA methylation status. Here, we describe and discuss the gene expression profile of neurally differentiated hcMSCs. These findings will expand our understanding of the molecular properties of MSCs and contribute to the development of cell therapy for neuroimmune diseases.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.274-274
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• 2004

The purpose of this study is to evaluate the efficacy of in vitro differentiated human embryonic stem (MB03) cells expressing Nurr1 in relief of symptomatic motor behavior of Parkinson's disease (PD) animal models. MB03 cell was genetically modified to express Nurr1 protein (Nr#24/MB03) and was induced to differentiate according to 2- /4+ protocol using retinoic acid and ascorbic acid. (omitted)

• 생명과학회지
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• 제26권12호
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• pp.1355-1359
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• 2016

인간 중간엽 줄기세포(hMSCs)는 신경세포(neuron-like cells)를 포함한 다양한 세포로 분화할 수 있는 능력을 지닌 성체 줄기세포(adult stem cells)이다. 본 연구에서는 인간의 골수유래-중간엽 줄기세포(bone marrow-mesenchymal stem cells; hBM-MSCs)를 이용한 신경분화에서 신경세포 표지자(neuronal marker)인 NF-M, Tuj-1 뿐만 아니라 성상세포 표지자(glial marker)인 GFAP의 발현 역시 의미 있게 증가함을 real-time PCR, Western blot, and immunocytochemical staining법을 통하여 관찰하였다. 이를 개선하기 위하여, 신경분화에 중요한 신호전달자(signal intermediator)인 PDE4를 억제한 후 신경분화를 유도하였다. PDE4 억제자인 rolipram 혹은 resveratrol를 각각 처리하여 신경분화한 줄기세포(Roli- or RSV-dMSCs)에서 NF-M, Tuj-1의 발현이 증가하였고 반면, GFAP의 발현은 감소함을 real-time PCR, Western blot, and immunocytochemical staining법을 통하여 관찰하였다. 본 연구를 통하여, PDE4를 조절하며 줄기세포의 신경분화를 개선할 수 있음을 보였다.

• Reproductive and Developmental Biology
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• 제36권1호
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• pp.33-37
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• 2012

Differential capacity of the parthenogenetic embryonic stem cells (PESCs) is still under controversy and the mechanisms of its neural induction are yet poorly understood. Here we demonstrated neural lineage induction of PESCs by addition of insulin-like growth factor-2 (Igf2), which is an important factor for embryo organ development and a paternally expressed imprinting gene. Murine PESCs were aggregated to embryoid bodies (EBs) by suspension culture under the leukemia inhibitory factor-free condition for 4 days. To test the effect of exogenous Igf2, 30 ng/ml of Igf2 was supplemented to EBs induction medium. Then neural induction was carried out with serum-free medium containing insulin, transferrin, selenium, and fibronectin complex (ITSFn) for 12 days. Normal murine embryonic stem cells derived from fertilized embryos (ESCs) were used as the control group. Neural potential of differentiated PESCs and ESCs were analyzed by immunofluorescent labeling and real-time PCR assay (Nestin, neural progenitor marker; Tuj1, neuronal cell marker; GFAP, glial cell marker). The differentiated cells from both ESC and PESC showed heterogeneous population of Nestin, Tuj1, and GFAP positive cells. In terms of the level of gene expression, PESC showed 4 times higher level of GFAP expression than ESCs. After exposure to Igf2, the expression level of GFAP decreased both in derivatives of PESCs and ESCs. Interestingly, the expression level of $Tuj1$ increased only in ESCs, not in PESCs. The results show that IGF2 is a positive effector for suppressing over-expressed glial differentiation during neural induction of PESCs and for promoting neuronal differentiation of ESCs, while exogenous Igf2 could not accelerate the neuronal differentiation of PESCs. Although exogenous Igf2 promotes neuronal differentiation of normal ESCs, expression of endogenous $Igf2$ may be critical for initiating neuronal differentiation of pluripotent stem cells. The findings may contribute to understanding of the relationship between imprinting mechanism and neural differentiation and its application to neural tissue repair in the future.

• 한국발생생물학회지:발생과생식
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• 제26권4호
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• pp.155-163
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• 2022

Human pluripotent stem cells (hPSCs) can give rise to a vast array of differentiated derivatives, which have gained great attention in the field of in vitro toxicity evaluation. We have previously demonstrated that hPSC-derived alveolar epithelial cells (AECs) are phenotypically and functionally similar to primary AECs and could be more biologically relevant alternatives for assessing the potential toxic materials including in fine dust and cigarette smoking. Therefore, in this study, we employed hPSC-AECs to evaluate their responses to exposure of various concentrations of diesel particulate matter (dPM), cigarette smoke extract (CSE) and nicotine for 48 hrs in terms of cell death, inflammation, and oxidative stress. We found that all of these toxic materials significantly upregulated the transcription of pro-inflammatory cytokines such as IL-1α, IL-β, IL-6, and TNF-α. Furthermore, the exposure of dPM (100 ㎍/mL) strongly induced upregulation of genes related with cell death, inflammation, and oxidative stress compared with other concentrations of CSE and nicotine. These results suggest that hPSC-AECs could be a robust in vitro platform to evaluate pulmotoxicity of various air pollutants and harmful chemicals.

• Journal of Periodontal and Implant Science
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• 제39권2호
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• pp.119-128
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• 2009

Purpose: The aim of this study was to evaluate the stemness of cells from canine dental tissues and bone marrow. Methods: Canine periodontal ligament stem cells (PDLSC), alveolar bone stem cells (ABSC) and bone marrow stem cells(BMSC) were isolated and cultured. Cell differentiations (osteogenic, adipogenic and chondrogenic) and surface antigens (CD146, STRO-1, CD44, CD90, CD45, CD34) were evaluated in vitro. The cells were transplanted into the subcutaneous space of nude mice to assess capacity for ectopic bone formation at 8 weeks after implantation. Results: PDLSC, ABSC and BMSC differentiated into osteoblasts, adipocytes and chondrocytes under defined condition. The cells expressed the mesenchymal stem cell markers differently. When transplanted into athymic nude mice, these three kinds of cells with hydroxyapatite /${\beta}$- tricalcium phosphate (HA/TCP) carrier showed ectopic bone formation. Conclusions: This study demonstrated that canine dental stem cells have stemness like bone marrow stem cells. Transplantation of these cells might be used as a therapeutic approach for dental stem cell-mediated periodontal tissue regeneration.