줄기세포 치료의 허와 실

오일환 대한의사협회 2013 대한의사협회지 Vol.56 No.10

Stem cell therapy has been taken as a highly promising area of future medicine due to its potential for providing new therapeutic modalities for debilitating, incurable diseases. In addition, stem cell therapy holds promise for its great industrial value due to the rapid growth of the market size. Recently, various types of stem cells such as induced pluripotent stem cells are being developed based on the conceptual revolution with regard to cell fate decisions. However, so far, most stem cell therapies have been performed using tissue-specific adult stem cells. Nevertheless, except for a few cases of stem cells such as hematopoietic stem cells that can regenerate hematopoietic tissue, a large proportion of stem cells, especially mesenchymal stromal cells, primarily work through paracrine functioning. The short life span of the injected stem cells and their paracrine mode of action pose a limitation to the maximum therapeutic efficacy that can be achieved from the current stem cell therapy model, warranting further research and development to enhance their efficacy. Despite the fact that stem cell therapies largely remain in the research stage, the public has expectations of rapid results and even fanaticism, leading to unauthorized stem cell practices and medical tourism. Moreover, the temptation to expedite the industrialization of stem cell therapeutics by simplifying the authorization process could increase the risk of endangering the rights of patients. Thus, stem cell therapy can become a ‘hope’ when society can overcome the stem cell ‘hype’.

Nuclear receptor regulation of stemness and stem cell differentiation

David J. Mangelsdorf,정양식 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.8

Stem cells include a diverse number of toti-, pluri-, and multi-potent cells that play important roles in cellular genesis and differentiation, tissue development, and organogenesis. Genetic regulation involving various transcription factors results in the self-renewal and differentiation properties of stem cells. The nuclear receptor (NR) superfamily is composed of 48 ligand-activated transcription factors involved in diverse physiological functions such as metabolism, development, and reproduction. Increasing evidence shows that certain NRs function in regulating stemness or differentiation of embryonic stem (ES) cells and tissue-specific adult stem cells. Here, we review the role of the NR superfamily in various aspects of stem cell biology, including their regulation of stemness, forward- and trans-differentiation events; reprogramming of terminally differentiated cells; and interspecies differences. These studies provide insights into the therapeutic potential of the NR superfamily in stem cell therapy and in treating stem cell-associated diseases (e.g., cancer stem cell). Stem cells include a diverse number of toti-, pluri-, and multi-potent cells that play important roles in cellular genesis and differentiation, tissue development, and organogenesis. Genetic regulation involving various transcription factors results in the self-renewal and differentiation properties of stem cells. The nuclear receptor (NR) superfamily is composed of 48 ligand-activated transcription factors involved in diverse physiological functions such as metabolism, development, and reproduction. Increasing evidence shows that certain NRs function in regulating stemness or differentiation of embryonic stem (ES) cells and tissue-specific adult stem cells. Here, we review the role of the NR superfamily in various aspects of stem cell biology, including their regulation of stemness, forward- and trans-differentiation events; reprogramming of terminally differentiated cells; and interspecies differences. These studies provide insights into the therapeutic potential of the NR superfamily in stem cell therapy and in treating stem cell-associated diseases (e.g., cancer stem cell).

Stem cell과 Myeloperoxidase가 스티렌, 하이드로퀴논 및 트리클로로에틸렌에 의한 림프구의 자매염색분체 교환과 소핵체 유도에 미치는 영향

이경재,김형아,신민정,성재혁,박정일,한훈,이세훈 대한산업의학회 2001 대한직업환경의학회지 Vol.13 No.3

목적 : 스티렌, 하이드필퀴논 및 트리클로로에틸렌 (TCE)이 사람의 stem cell과 human myeloperoxidase (MPO)에 의해 대사성 활성화되는 지를 규명하고자 스티렌, 하이드로퀴논 및 TCE에 사람의 stem cell 또는 MPO 효소의 첨가가 이들 화학물질에 의한 자매염색분체교환(SCE)과 소핵체 (MN) 빈도에 미치는 영향을 관찰하였다. 방법 : 건강한 남자의 전혈에서 림프루를 분리하여 72시간동안 이중배양하되 배양개시 24시간만에 0.05mM 하이드로퀴논, 1.50 mM 스티렌, 혹은 1.50mM TCE를 전체용량이 30 ㎕가 되도록 아세톤에 희석하여 배양액에 주입하였고 대조군은 아세톤으로 처리하였다. 화학물질 처리 후 즉시 1.3×106 및 2.6×106 cells/ml 농도의 제대혈액으로부터 나온 stem cell 세포액의 상층액이나 1.0 및 2.0 unit의 human myeloperoxidase를 H2O2와 함께 첨가하였다. SCE분석을 위한 배양액에는 배양종료 2.5시간 전에 colchicine을 가한 후 수확하여 Giemsa염색을 하여 metaphase 세포에서 SCE빈도를 분석하였다. MN분석을 위한 배양액에는 배양개시 44시간만에 cytochalasin-B를 가하였고 acridine orange 염색 후 이핵체에서 MN수를 분석하였다. 결과 : 1. stem cell이나 MPO 자체는 SCE나 MN의 빈도에 영향을 미치지 않았다. 2. stem cell이나 MPO는 스티렌에 의해 유도되는 SCE의 빈도를 용량-반응관계로 유의하게 증가시켰고, MN빈도의 경우 step cell이나 MPO에 의해 증가되는 경향이 있었으나 2.0 unit MPO를 첨가한 경우에만 첨가하지 않은 경우에 비하여 유의하게 증가하였다. 3. 하이드로퀴논은 stem cell이나 MPO가 없는 상태에서도 대조군에 비하여 SCE빈도가 대조군에 비하여 높았다. stem cell이나 MPO는 하이드로퀴논에 의한 SCE 빈도를 용량 반응관계로 유의하게 증가시켰지만, MN의 경우에는 증가시키는 경향만 있을 뿐 유의한 차이는 아니었다. 4. TCE자체는 SCE나 MN빈도를 증가시키지 않았다. stem cell은 1.3 ×106 및 2.6 × 106 cells/ml 농도 모두에서 SCE빈도를 유의하게 증가시켰고 MPO는 2.0 unit농도에서만 유의하게 증가시켰다. stem cell이나 MPO모두 TCE에 의한 MN빈도를 증가시키는 경향이 있었으나 유의한 차이는 아니었다. 결론 : 저자들은 스티렌, 하이드로퀴논, 및 트리클로로에틸렌에 의해 유도되는 자매염색분체교환과 소핵체의 빈도가 사람의 stem cell이나 myeloperoxidase에 의해 증가됨을 발견하였으며, 이러한 결과는 myeloperoxidase가 이들 물질의 대사성활성화에 관여함을 암시하고, 또한 아마도 이 물질들의 골수독성과 관련이 있는 것이라고 제시된다. Objectives : The objective of this study was to identify the possible role of stem cell and myeloperoxidase (MPO) in the metabolic activation of styrene, hydroquinone and trichloroethylene, by investigating the effects of stem cell from umbilical cord blood and MPO on the frequency of sister chromatid exchange (SCE) and micronuclei (MN) induction in cultured human peripheral lymphocytes exposed to hese chemicals. Methods : Islated lymphocytes from whole blood were cultured for 72 hours. The cells were treated with 1.50 mM styrene, 50 μM hydroquinone and 1.50 mM trichloroethylene dissolved with acetone (30㎕ in total volume) at 24 hours after the beginning of culture. Control group was treated with acetone only. Immediately after adding these chemicals, 1.3×106 cells/ml and 2.6×106 cells/ml stem cell/ml stained with Giemsa's solution, and acridine orange for sister chromatid exchange, and for micronucleus analysis, respectively. Results : The results were as follows: 1) Myeloperoxidase and stem cell did not significantly affect the frequencies of SCE or MN in the control group. 2) The frequency of SCE or MN with exposure to styrene did not different from control in the absence of stem cell or MPO. Sister chromatid exchange induced by styrene was significantly increased by adding stem cell or MPO in dose-dependent relationship. The frequency of MN induced by styrene significantly increased in the presence of 2.0 unit MPO. 3) The frequency of SCE was significantly increased with exposure to hydroquinone than acetone treated control in the absence of stem cell or MPO. Sister chromatid exchange induction by hydroquinone significantly increased dose-dependently in the presence of stem cell or MPO. There was a tnendency of increase of the MN frequency induced by hydroquinone in the presence of stem cell or MPO, but not significant. 4) It was found that trichloroethylene itself did not increase SCE or MN frequency. Frequency of SCE induced by trichloroethylene was significantly increased with adding stem cell (low and high) and 2.0 unit MPO. Even though them cell or MPO increased the frequency of MN of lymphocyte exposed to trichloroethylene, the difference was not significant. Conclusions : Authors found that the frequencies of both sister chromatid exchange and micronucleus induced by styrene, hydroquinone, and trichloroethylene were increased significantly with the treatment of stem cell or myeloperoxidase. It was suggested that myeloperoxidase may therefore play an important role in the metabolic activation of styrene, hydroquinone, and trichloroethylene and myeloperoxidase probably be involved in the myelotoxicity of these chemicals.

질병치료제로서 줄기세포의 특성

서검석 ( Geom Seog Seo ) 대한소화기학회 2011 대한소화기학회지 Vol.58 No.3

Stem cell research is a innovative technology that focuses on using undifferentiated cells able to self-renew through the asymmetrical or symmetrical divisions. Three types of stem cells have been studied in laboratory including embryonic stem cell, adult stem cells and induced pluripotent stem cells. Embryonic stem cells are pluripotent stem cells derived from the inner cell mass and it can give rise to any fetal or adult cell type. Adult stem cells are multipotent, have the ability to differentiate into a limited number of specialized cell types, and have been obtained from the bone marrow, umbilical cord blood, placenta and adipose tissue. Stem cell therapy is the most promising therapy for several degenerative and devastating diseases including digestive tract disease such as liver failure, inflammatory bowel disease, Celiac sprue, and pancreatitis. Further understanding of biological properties of stem cells will lead to safe and successful stem cell therapies. (Korean J Gastroenterol 2011;58:125-132)

Profiling of Differentially Expressed Genes in Human Stem Cells by cDNA Microarray

김철근,이종주,정대영,전진선,허현석,강호철,신준호,조윤신,차경준,김찬길,도병록,김경숙,김현수 한국분자세포생물학회 2006 Molecules and cells Vol.21 No.3

Stem cells are unique cell populations with the ability to undergo both self-renewal and differentiation, although a wide variety of adult stem cells as well as embryonic stem cells have been identified and stem cell plasticity has recently been reported. To identify genes implicated in the control of the stem cell state as well as the characteristics of each stem cell line, we analyzed the expression profiles of genes in human embryonic, hematopoietic (CD34+ and CD133+), and mesenchymal stem cells using cDNA microarrays, and identified genes that were differentially expressed in specific stem cell populations. In particular we were able to identify potential hESC signature-like genes that encode transcription factors (TFAP2C and MYCN), an RNA binding protein (IMP-3), and a functionally uncharacterized protein (MAGEA4). The overlapping sets of 22 up-regulated and 141 downregulated genes identified in this study of three human stem cell types may also provide insight into the developmental mechanisms common to all human stem cells. Furthermore, our comprehensive analyses of gene expression profiles in various adult stem cells may help to identify the genetic pathways involved in self-renewal as well as in multi-lineage specific differentiation.

치수, 치주인대 및 치낭에서 얻어진 성체줄기세포의 조골세포로의 분화능력 평가에 관한 연구

이중규(Joong-Kyou Lee),이재훈(Jae-Hoon Lee) 대한구강악안면외과학회 2010 대한구강악안면외과학회지 Vol.36 No.1

Complex human tissues harbor stem cells and precursor cells, which are responsible for tissue development or repair. Recently, dental tissues such as dental pulp, periodontal ligament (PDL), dental follicle have been identified as easily accessible sources of undifferentiated cells. These tissues contain mesenchymal stem cells that can be differentiate into bone, cartilage, fat or muscle by exposing them to specific growth conditions. In this study, the authors procured the stem cell from pulp, PDL, and dental follicle and differentiate them into osteoblast and examine the bone induction capacity. Dental pulp stem cell (DPSC), periodontal ligament stem cell (PDLSC), and dental follicle precursor cell (DFPC) were obtained from human 3rd molar and cultured. Each cell was analyzed for presence of stem cell by fluorescence activated cell sorter (FACs) against CD44, CD105 and CD34, CD45. Each stem cell was cultured, expanded and grown in an osteogenic culture medium to allow formation of a layer of extracellular bone matrix. Osteogenic pathway was checked by alizarin red staining, alkaline phosphatase (ALP) activity test and RT-PCR for ALP and osteocalcin (OCN) gene expression. According to results from FACs, mesenchymal stem cell existed in pulp, PDL, and dental follicle. As culturing with bone differentiation medium, stem cells were differentiated to osteoblast like cell. Compare with stem cell from pulp, PDL and dental follicle-originated stem cell has more osteogenic effect and it was assumed that the character of donor cell was able to affect on differential potency of stem cell. From this article, we are able to verify the pulp, PDL, and dental follicle from extracted tooth, and these can be a source of osteoblast and stem cell for tissue engineering.

줄기세포의 개요

허용준,김동욱 대한의사협회 2011 대한의사협회지 Vol.54 No.5

We are now in the middle of stem cell war. Each country is trying to invest a large amount of funds into stem cell research. This is due to a potentiality of stem cells. Stem cells are capable of proliferating in an undifferentiated manner and are able to differentiate into a desired cell lineage under certain conditions. These abilities make stem cells an appealing source for cell replacement therapies (regenerative medicine), the study of developmental biology and drug/toxin screening. In addition to embryonic and adult stem cells, induced pluripotent stem (iPS) cells has been recently generated through reprogramming from adult tissue cells such as fibroblasts. This technique has opened up new avenues to generate patient- and disease-specific pluripotent stem cells. Human iPS cells may be useful for gaining valuable insight into the pathophysiology of disease, as well as for discovering for new prognostic biomarkers and drug screening. Moreover,the iPS cell technology may play a major role in immune-matched clinical application in the future. In this chapter, we introduce general characteristics of various stem cells, clinical application of stem cells and future perspectives.

Evaluation of the maintenance of stemness, viability, and differentiation potential of gingiva-derived stem-cell spheroids

Lee, Sung-Il,Ko, Youngkyung,Park, Jun-Beom D.A. Spandidos 2017 Experimental and therapeutic medicine Vol.13 No.5

<P>Gingiva-derived stem cells have been applied for tissue-engineering purposes and may be considered a favorable source of mesenchymal stem cells as harvesting stem cells from the mandible or maxilla may be performed with ease under local anesthesia. The present study was performed to fabricate stem-cell spheroids using concave microwells and to evaluate the maintenance of stemness, viability, and differentiation potential. Gingiva-derived stem cells were isolated, and the stem cells of 4×10<SUP>5</SUP> (group A) or 8×10<SUP>5</SUP> (group B) cells were seeded into polydimethylsiloxane-based, concave micromolds with 600 µm diameters. The morphology of the microspheres and the change of the diameters of the spheroids were evaluated. The viability of spheroids was qualitatively analyzed via Live/Dead kit assay. A cell viability analysis was performed on days 1, 3, 6, and 12 with Cell Counting Kit-8. The maintenance of stemness was evaluated with immunocytochemical staining using SSEA-4, TRA-1-60(R) (positive markers), and SSEA-1 (negative marker). Osteogenic, adipogenic, and chondrogenic differentiation potential was evaluated by incubating spheroids in osteogenic, adipogenic and chondrogenic induction medium, respectively. The gingiva-derived stem cells formed spheroids in the concave microwells. The diameters of the spheroids were larger in group A than in group B. The majority of cells in the spheroids emitted green fluorescence, indicating the presence of live cells at day 6. At day 12, the majority of cells in the spheroids emitted green fluorescence, and a small portion of red fluorescence was also noted, which indicated the presence of dead cells. The spheroids were positive for the stem-cell markers SSEA-4 and TRA-1-60(R) and were negative for SSEA-1, suggesting that these spheroids primarily contained undifferentiated human stem cells. Osteogenic, adipogenic, and chondrogenic differentiation was more evident with an increase of incubation time: Mineralized extracellular deposits were observed following Alizarin Red S staining at days 14 and 21; oil globules were increased at day 18 when compared with day 6; and Alcian blue staining was more evident at day 18 when compared with day 6. Within the limits of this study, stem-cell spheroids from gingival cells maintained the stemness, viability, and differentiation potential during the experimental periods. This method may be applied for a promising strategy for stem-cell therapy.</P>

Study of Functional Cosmetics Based on Stem Cell Technology

최성현,윤지수,권상모 한국조직공학과 재생의학회 2015 조직공학과 재생의학 Vol.12 No.4

Considering the steady increase in life expectancy slowing or reversing the deleterious effects of aging has garnered considerable interest. Accordingly, functional cosmetics based on stem cell technology (Stem cell cosmetics), which combine the anti-aging concept with high technology, is an emerging trend in the cosmetics industry. Stem cells possess self-renewal properties and the potency to differentiate. Therefore, stem cells are the most important cells in the skin, as they are the source for continuous regeneration of the epidermis. Stem cell cosmetics are developed based on stem cell technology, which involves using extracts or culture media of stem cells. However, cosmetics containing stem cells or their extracts have not been released into the market due to legal, ethical, and safety concerns. Meanwhile, plant stem cells, which circumvent these problems, are highly regarded in the cosmetics industry for improving culture technology. The European Union prohibits the use of cells, tissues, or products of human origin in cosmetics, whereas the Korea Food and Drug Association has allowed the use of sources originating from stem cell media in cosmetics since 2009. The global cosmetics market is worth more than 242 billion dollars; however, cosmetic companies across the world that are developing and launching stem cell cosmetics based on stem cell activators, culture extracts, and culture media are much more focused on the Korean cosmetic market.

Genomics and proteomics in stem cell research

Sung-Min Ahn,Richard Simpson,Bonghee Lee 대한해부학회 2010 Anatomy & Cell Biology Vol.43 No.1

Stem cell research has been widely studied over the last few years and has attracted increasing attention from researchers in all fields of medicine due to its potential to treat many previously incurable diseases by replacing damaged cells or tissues. As illustrated by hematopoietic stem research, understanding stem cell differentiation at molecular levels is essential for both basic research and for clinical applications of stem cells. Although multiple integrative analyses, such as genomics, epigenomics, transcriptomics and proteomics, are required to understand stem cell biology, proteomics has a unique position in stem cell research. For example, several major breakthroughs in HSC research were due to the identification of proteins such as colony-stimulating factors (CSFs) and cell-surface CD molecules. In 2007, the Human Proteome Organization (HUPO) and the International Society for Stem Cell Research (ISSCR) launched the joint Proteome Biology of Stem Cells Initiative. A systematic proteomics approach to understanding stem cell differentiation will shed new light on stem cell biology and accelerate clinical applications of stem cells.