• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제38권6호
• /
• pp.343-353
• /
• 2012

Objectives: This aim of this study was to effectively isolate mesenchymal stem cells (hSMSCs) from human submandibular skin tissues (termed hSMSCs) and evaluate their characteristics. These hSMSCs were then chemically induced to the neuronal lineage and analyzed for their neurogenic characteristics in vitro. Materials and Methods: Submandibular skin tissues were harvested from four adult patients and cultured in stem cell media. Isolated hSMSCs were evaluated for their multipotency and other stem cell characteristics. These cells were differentiated into neuronal cells with a chemical induction protocol. During the neuronal induction of hSMSCs, morphological changes and the expression of neuron-specific proteins (by fluorescence-activated cell sorting [FACS]) were evaluated. Results: The hSMSCs showed plate-adherence, fibroblast-like growth, expression of the stem-cell transcription factors Oct 4 and Nanog, and positive staining for mesenchymal stem cell (MSC) marker proteins (CD29, CD44, CD90, CD105, and vimentin) and a neural precursor marker (nestin). Moreover, the hSMSCs in this study were successfully differentiated into multiple mesenchymal lineages, including osteocytes, adipocytes, and chondrocytes. Neuron-like cell morphology and various neural markers were highly visible six hours after the neuronal induction of hSMSCs, but their neuron-like characteristics disappeared over time (24-48 hrs). Interestingly, when the chemical induction medium was changed to Dulbecco's Modified Eagle Medium (DMEM) supplemented with fetal bovine serum (FBS), the differentiated cells returned to their hSMSC morphology, and their cell number increased. These results indicate that chemically induced neuron-like cells should not be considered true nerve cells. Conclusion: Isolated hSMSCs have MSC characteristics and express a neural precursor marker, suggesting that human skin is a source of stem cells. However, the in vitro chemical neuronal induction of hSMSC does not produce long-lasting nerve cells and more studies are required before their use in nerve-tissue transplants.

• Reproductive and Developmental Biology
• /
• 제32권2호
• /
• pp.105-110
• /
• 2008

The endogenous retrovirus-like elements (HERVs) found on several human chromosomes are somehow involved in gene regulation, especially during the transcription level. HERV-H, located on chromosome Xp22, may regulate gastrin-releasing peptide receptor (GRPR) in connection with diverse diseases. By suppression subtractive hybridization screen on SV40-immortalized lung fibroblast (WI-38 VA-13), we discovered that expression of HERV-HX2, a clustered HERV-H sequence on chromosome X, was upregulated in immortalized lung cells, compared to that of normal cells. Expression of HERV-HX2 was then analyzed in various cell lines, including normal somatic cells, cancer cells, SV40-immortalized cells, and undifferentiated and differentiated human embryonic stem cells. Expression of HERV-HX2 was specifically upregulated in continuously-dividing cells, such as cancer cells and SV40-immortalized cells. Especially, HERV-HX2 in HeLa cells was highly upregulated during the S phase of the cell cycle. Similar results were obtained in hES cells, in which undifferentiated cells expressed more HERV-HX2 mRNA than differentiated hES cells, including neural precursor and endothelial progenitor cells. Taken together, our results suggest that HERV-HX2 is upregulated in cancer cells and undifferentiated hES cells, whereas downregulated as differentiation progress. Therefore, we assume that HERV-HX2 may playa role on proliferation of cancer cells as well as differentiation of hES cells in the transcriptional level.

• Journal of Veterinary Science
• /
• 제22권1호
• /
• pp.7.1-7.13
• /
• 2021

Background: Niemann-Pick disease type C (NPC) is caused by the mutation of NPC genes, which leads to the abnormal accumulation of unesterified cholesterol and glycolipids in lysosomes. This autosomal recessive disease is characterized by liver dysfunction, hepatosplenomegaly, and progressive neurodegeneration. Recently, the application of induced neural stem cells (iNSCs), converted from fibroblasts using specific transcription factors, to repair degenerated lesions has been considered a novel therapy. Objectives: The therapeutic effects on NPC by human iNSCs generated by our research group have not yet been studied in vivo; in this study, we investigate those effects. Methods: We used an NPC mouse model to efficiently evaluate the therapeutic effect of iNSCs, because neurodegeneration progress is rapid in NPC. In addition, application of human iNSCs from NPC patient-derived fibroblasts in an NPC model in vivo can give insight into the clinical usefulness of iNSC treatment. The iNSCs, generated from NPC patientderived fibroblasts using the SOX2 and HMGA2 reprogramming factors, were transplanted by intracerebral injection into NPC mice. Results: Transplantation of iNSCs showed positive results in survival and body weight change in vivo. Additionally, iNSC-treated mice showed improved learning and memory in behavior test results. Furthermore, through magnetic resonance imaging and histopathological assessments, we observed delayed neurodegeneration in NPC mouse brains. Conclusions: iNSCs converted from patient-derived fibroblasts can become another choice of treatment for neurodegenerative diseases such as NPC.

• 한국동물번식학회:학술대회논문집
• /
• 한국동물번식학회 2004년도 춘계학술발표대회
• /
• pp.273-273
• /
• 2004

This study was to examine in vitro neural cell differentiation pattern of the genetically modified human embryonic stem cells expressing tyrosine hydroxylase (TH). Human embryonic stem (hES, MB03) cell was transfected with cDNAs cording for TH. Successful transfection was confirmed by western immunoblotting. (omitted)

• 생약학회지
• /
• 제46권1호
• /
• pp.52-58
• /
• 2015

Neural stem cells (NSCs), with self-renewal and neuronal differentiation capacity, are a feasible resource in cell-based therapies for various neurodegenerative diseases and neural tissue injuries. In this study, we investigated the effects of Schisandrae Fructus (SF) on proliferation and differentiation of human embryonic NSCs. Treatment with 70% ethanol extract of SF increased the viability of NSCs derived from human embryonic stem cells, which was accompanied by increased mRNA expression of cyclin D1. Whereas 70% ethanol extract of SF also decreased the mRNA expression of nestin, it increased class III ${\beta}$-tublin (Tuj-1) and MAP2 in both growth and differentiation media. Lastly, we found increased mRNA expression of BDNF in SF-treated NSCs. In conclusion, our study demonstrates for the first time that SF induced proliferation and neuronal differentiation of NSCs and increased mRNA expression of BDNF, suggesting its potential as a regulator of NSC fate in NSC-based therapy for neuronal injuries from various diseases.

• 생명과학회지
• /
• 제26권1호
• /
• pp.8-16
• /
• 2016

적절한 농도의 활성산소종(ROS)은 병원체에 대한 세포의 방어, 신호 전달, 세포 성장 및 유전자 발현을 포함한 다양한 정상 세포 기능을 매개한다. 최근의 연구는 ROS와 ROS를 생성하는 NADPH 산화 효소(Nox)가 성인 쥐 뇌의 뇌실 하 영역(SVZ)에 있는 신경 줄기세포의 자가 복제와 신경 세포 분화에 중요하다는 것을 보여 주었다. 본 연구에서 세포 내 ROS가 갓 태어난 쥐의 뇌에서 적출되어 배양된 SVZ 신경 줄기세포에서 검출된 것으로 나타났다. Nox 유사 유전자들 중 Nox4가 배양된 세포에서 주로 발현되었고, Nox1과 Nox2는 거의 발현되지 않았다. 또한, Nox4 유전자는 신경 세포 분화 동안 최대 10배까지 발현이 크게 증가하였다. Immunocytochemistry결과 Nox4 단백질은 신경 세포 특이적인 tubulin인 Tuj1-양성 신경 세포에서 주로 발견되었다. 이와 맥을 같이 하여, 내인성 ROS는 분화 후 축삭돌기를 가지고 있으며 신경 세포로 보이는 세포에서만 검출되었다. 또한, ROS를 제거하는N-acetyl cysteine에 의해 세포 산화 환원 상태가 교란되었을 때, 신경 세포로의 분화가 크게 감소하였다. 마지막으로, shRNA를 이용하 여 Nox4를 knockdown한 세포에서 신경 세포로의 분화가 감소하였다. 이러한 연구 결과는 Nox4가 갓 태어난 쥐의 SVZ 신경 줄기 세포의 주요한 ROS 생성 효소이고, Nox4에 의한 ROS생성이 신경 세포 분화에 중요하다는 것을 암시한다.

• Clinical and Experimental Reproductive Medicine
• /
• 제38권4호
• /
• pp.216-221
• /
• 2011

Objective: To differentiate the human embryonic stem cells (hESCs) into the retinal pigment epithelium (RPE) in the defined culture condition and determine its therapeutic potential for the treatment of retinal degenerative diseases. Methods: The embryoid bodies were formed from hESCs and attached on the matrigel coated culture dishes. The neural structures consisting neural precursors were selected and expanded to form rosette structures. The mechanically isolated neural rosettes were differentiated into pigmented cells in the media comprised of N2 and B27. Expression profiles of markers related to RPE development were analyzed by reverse transcription-polymerase chain reaction and immunostaining. Dissociated putative RPE cells ($10^5$ cells/5 ${\mu}L$) were transplanted into the subretinal space of rat retinal degeneration model induced by intravenous sodium iodate injection. Animals were sacrificed at 1, 2, and 4 weeks after transplantation, and immnohistochemistry study was performed to verify the survival of the transplanted cells. Results: The putative RPE cells derived from hESC showed characteristics of the human RPE cells morphologically and expressed molecular markers and associated with RPE fate. Grafted RPE cells were found to survive in the subretinal space up to 4 weeks after transplantation, and the expression of RPE markers was confirmed with immunohistochemistry. Conclusion: Transplanted RPE cells derived from hESC in the defined culture condition successfully survived and migrated within subretinal space of rat retinal degeneration model. These results support the feasibility of the hESC derived RPE cells for cell-based therapies for retinal degenerative disease.

• Molecules and Cells
• /
• 제42권9호
• /
• pp.617-627
• /
• 2019

Brain organoids are an exciting new technology with the potential to significantly change our understanding of the development and disorders of the human brain. With step-by-step differentiation protocols, three-dimensional neural tissues are self-organized from pluripotent stem cells, and recapitulate the major millstones of human brain development in vitro. Recent studies have shown that brain organoids can mimic the spatiotemporal dynamicity of neurogenesis, the formation of regional neural circuitry, and the integration of glial cells into a neural network. This suggests that brain organoids could serve as a representative model system to study the human brain. In this review, we will overview the development of brain organoid technology, its current progress and applications, and future prospects of this technology.

• Clinical and Experimental Reproductive Medicine
• /
• 제29권2호
• /
• pp.117-127
• /
• 2002

Objective: This study was to investigate the generation of the functional neuron derived from human embryonic stem (hES, MB03) cells on in vitro neural cell differentiation system. Methods: For neural progenitor cell formation derived from hES cells, we produced embryoid bodies (EB: for 5 days, without mitogen) from hES cells and then neurospheres (for $7{\sim}10$ days, 20 ng/ml of bFGF added N2 medium) from EB. And then finally for the differentiation into mature neuron, neural progenitor cells were cultured in i) N2 medium only (without bFGF), ii) N2 supplemented with 20 ng/ml platelet derived growth factor-bb (PDGF-bb) or iii) N2 supplemented with 5 ng/ml brain derived neurotrophic factor (BDNF) for 2 weeks. Identification of neural cell differentiation was carried out by immunocytochemistry using $\beta_{III}$-tubulin (1:250), MAP-2 (1:100) and GFAP (1:500). Also, generation of functional neuron was identified using anti-glutamate (Sigma, 1:1000), anti-GABA (Sigma, 1:1000), anti-serotonin (Sigma, 1:1000) and anti-tyrosine hydroxylase (Sigma, 1:1000). Results: In vitro neural cell differentiation, neurotrophic factors (PDGF and BDNF) treated cell groups were high expressed MAP-2 and GFAP than non-treated cell group. The highest expression pattern of MAP-2 and $\beta_{III}$-tubulin was indicated in BDNF treated group. Also, in the presence of PDGF-bb or BDNF, most of the neural cells derived from hES cells were differentiated into glutamate and GABA neuron in vitro. Furthermore, we confirmed that there were a few serotonin and tyrosine hydroxylase positive neuron in the same culture environment. Conclusion: This results suggested that the generation of functional neuron derived from hES cells was increased by addition of neurotrophic factors such as PDGF-bb or BDNF in b-FGF induced neural cell differentiation system and especially glutamate and GABA neurons were mainly produced in the system.

• 대한생식의학회:학술대회논문집
• /
• 대한불임학회 2002년도 제42차 춘계학술대회
• /
• pp.74.2-75
• /
• 2002