• 한국발생생물학회지:발생과생식
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• 제14권3호
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• pp.155-162
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• 2010

The trophectoderm is one of the earliest cell types to differentiate in the forming placenta. It is an important for the initial implantation and placentation during pregnancy. Trophoblast stem cells (TBSCs) develop from the blastocyst and are maintained by signals emanating from the inner cell mass. However, several limitations including rarity and difficulty in isolation of trophoblast stem cells derived from blastocyst still exist. To establish a model for trophoblast differentiation, we isolated TBSCs from human term placenta ($\geq$38 weeks) and characterized. Cell cycle was analyzed by measuring DNA content by FACS analysis and phenotype of TBSCs was characterized by RT-PCR and FACS analysis. TBSCs have expressed various markers such as self-renewal markers (Nanog, Sox2), three germ layer markers (hNF68, alpha-cardiac actin, hAFP), trophoblast specific markers (CDX-2, CK7, HLA-G), and TERT gene. In FACS analysis, TBSCs isolated from term placenta showed that the majority of cells expressed CD13, CD44, CD90, CD95, CD105, HLA-ABC, cytokeratin 7, and HLA-G. Testing for CD31, CD34, CD45, CD71, vimentin and HLA-DR were negative. TBSCs were shown to decrease the growth rate when cultured in conditioned medium without FGF4/heparin as well as the morphology was changed to a characteristic giant cell with a large cytoplasm and nucleus. In invasion assay, TBSCs isolated from term placenta showed invasion activities in in vivo using nude mice and in vitro Matrigel system. Taken together, these results support that an isolation potential of TBSCs from term placenta as well as a good source for understanding of the infertility mechanism.

• 대한두경부종양학회:학술대회논문집
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• 대한두경부종양학회 1995년도 제12차 학술대회 연제순서 및 초록집
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• pp.199.1-199.1
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• 1995

• Molecules and Cells
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• 제39권4호
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• pp.286-291
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• 2016

Epstein-Barr virus (EBV) is the prototypical ${\gamma}$-herpesvirus and an obligate human pathogen that infects mainly epithelial cells and B cells, which can result in malignancies. EBV infects these target cells by fusing with the viral and cellular lipid bilayer membranes using multiple viral factors and host receptor(s) thus exhibiting a unique complexity in its entry machinery. To enter epithelial cells, EBV requires minimally the conserved core fusion machinery comprised of the glycoproteins gH/gL acting as the receptor-binding complex and gB as the fusogen. EBV can enter B cells using gp42, which binds tightly to gH/gL and interacts with host HLA class II, activating fusion. Previously, we published the individual crystal structures of EBV entry factors, such as gH/gL and gp42, the EBV/host receptor complex, gp42/HLA-DR1, and the fusion protein EBV gB in a postfusion conformation, which allowed us to identify structural determinants and regions critical for receptor-binding and membrane fusion. Recently, we reported different low resolution models of the EBV B cell entry triggering complex (gHgL/gp42/HLA class II) in "open" and "closed" states based on negative-stain single particle electron microscopy, which provide further mechanistic insights. This review summarizes the current knowledge of these key players in EBV entry and how their structures impact receptor-binding and the triggering of gB-mediated fusion.

• Clinical and Experimental Reproductive Medicine
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• 제36권1호
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• pp.23-34
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• 2009

목 적: 중간엽 줄기세포를 임상에 적용하기 위해서는 체외 배양을 통한 세포증식 과정이 필요하나, 오랜 기간 동안 체외 배양을 하게 되면 노화되어 특성이 변하고 분화 능력 또한 감소하게 된다. 따라서 현재까지는 초기 계대배양의 세포만이 임상에 적용되고 있는 실정이며 체외에서의 세포 배양이 세포의 특성에 미치는 영향에 대한 연구와 함께 세포의 특성 변화 없이 체외증식이 가능하도록 하는 연구들이 골수 및 지방유래 중간엽 줄기세포에서 보고되고 있다. 그러나 현재 탯줄유래 줄기세포의 체외 배양에 따른 특성 변화 분석 연구는 아직 잘 이루어지지 않고 있다. 본 연구의 목적은 탯줄유래 줄기세포의 체외 배양 시 계대배양 증가에 따른 줄기세포의 특성 변화를 분석하고자 하였다. 연구방법: 사람의 탯줄유래 줄기세포 (human umbilical cord-derived stem cells, HUC)를 분리하여 in vitro에서 계대배양하였다. 계대배양에 따른 세포의 형태와 population doubling time (PDT)을 조사하고 RT-PCR 방법을 이용하여 mRNA 분석을 하였으며 면역세포화학 염색법을 이용하여 단백질 발현을 분석하였다. 결 과: 탯줄유래 줄기세포는 평균 10번의 계대배양 후 senescence를 나타냈다. 세포의 형태는 7번째 계대배양 이후 세포질이 넓어지고 세포의 크기가 커지는 변화를 나타냈으며 PDT가 증가하기 시작하였다. 계대배양 4, 8, 10번째 시기의 세포의 mRNA 변화를 분석한 결과 Oct-4, HNF-4${\alpha}$, mRNA는 10번째 계대배양까지 지속적으로 발현하였으나 nestin, vimentin mRNA는 지속적으로 발현이 감소하였고 SCF mRNA는 지속적으로 발현이 감소하였다. 이에 반해 HLA-DR${\alpha}$, Pax-6, BMP-2 mRNA는 모든 계대배양 시기의 세포에서 발현되지 않았다. 면역세포화학 분석법을 통한 3, 6, 9번째 계대배양 세포의 단백질 발현 분석 결과 SSEA-3와 SSEA-4는 3, 6, 9번째 계대배양 세포 모두에서 발현하였으나 ICAM-1과 HLA-ABC는 계대배양이 증가함에 따라 발현이 증가되었다. Thy-1 단백질은 p9에서 발현이 증가되었으며 이와 반대로 TRA-1-60와 VCAM-1 단백질은 p6과 p9 시기에 발현이 감소되었다. HLA-DR 단백질은 모든 계대배양 시기에 발현되지 않았다. 결 론: 본 연구결과 탯줄유래 줄기세포는 체외 배양 시 줄기세포 특성이 일부 변하는 것을 관찰하였다. 앞으로 줄기세포의 특성을 유지할 수 있는 체외 배양법의 발달을 위한 연구들이 수행 되야 할 것으로 사료된다.

• BMB Reports
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• 제43권3호
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• pp.164-169
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• 2010

CpG-DNA, which contains unmethylated CpG dinucleotides in the context of specific sequences, has remarkable and diverse immunological effects, including induction of proinflammatory cytokine expression and regulation of the Th1/Th2 immune response. Here, we examined the immunostimulatory activities of double-stranded (ds) CpG-DNA in the human B cell line RPMI8226. To investigate whether dsCpG-DNA stimulates immune cells, we constructed a plasmid containing repeated dsCpG-DNA and produced dsCpG-DNA by PCR amplification and EcoR I digestion. PCR-amplified dsCpG-DNA alone did not have immmunostimulatory activity. However, dsCpGDNA encapsulated with lipofectin induced IL-8 promoter activation, HLA-DRA expression, and IL-8 expression in a CG sequence-independent manner. The effects of encapsulated dsCpGDNA were independent of minor endotoxin contamination. These findings suggest the potential use of dsCpG-DNA as a therapy for immune response regulation.

• Tuberculosis and Respiratory Diseases
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• 제39권4호
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• pp.334-342
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• 1992

연구배경 : Mycobacteria 감염에 의한 폐결핵은 세포매개성 면역 반응이 관계한다고 알려져 있는 바, 먼저 Mycobacteria가 흡입되면 T 임파구가 활성화되어 세포매개성 면역 반응을 나타낸다. 결핵환자에서 tuberculin-purified protein derivative에 대한 피부 면역반응은 주로 세포매개성 면역반응에 의해 이루어짐으로 활동성 폐결핵 환자에서는 양성반응을 나타내어야하나 활동성 폐결핵 환자에서도 음성반응(anergy)을 나타내는 경우가 있다. 저자들은 폐결핵 환자에서 말초혈액 및 기관지 폐포세액내의 임파구의 세포조성과 이들이 피부반응에 미치는 영향을 조사함으로써 활동성 폐결핵 환자에서의 PPD에 대한 피부반응 검사상 음성으로 나타나는 이유를 알아보고자 하였다. 방법 : 11명의 정상대조군, 20명의 활동성 폐결핵 환자를 대상으로 PPD에 대한 피부 반응 검사 및 말초 혈액 및 기관지 폐포세척액의 임파구의 아형을 분석하였다. 결과 : 1) 기관지 폐포세척액내의 임파구는 환자군에서 정상대조군에 비하여 유의하게 증가되어 있었고($25.2{\pm}4.8$ vs $6.6{\pm}1.3%$, p<0.01), 단구세포(monocyte)는 환자군에서 정상 대조군에 비하여 유의하게 감소되어 있었다($69.6{\pm}5.7$ vs $89.2{\pm}1.4%$, p<0.05). 2) PPD에 대한 양성 반응을 보인 환자군과 음성 반응을 보인 환자군 사이의 기관지 폐포세척 세포 조성의 비는 차이가 없었다. 3) 환자군에서 기관지 폐포세척액 내의 $CD3^+$, $CD4^+$ 임파구의 조성비는 말초혈액보다 유의하게 증가되어 있었고($CD3^+$: $76.56{\pm}2.18$ vs $57.59{\pm}2.17%$, p<0.001; $CD4^+$: $51.24{\pm}2.33$ vs $35.20{\pm}2.32%$, p<0.005), $CD3^+IL-2R^+$, $CD3^+HLA-DR^+$ 임파구의 조성비도 말초혈액보다 증가되어 있었다($CD3^+IL-2R^+$:$2.41{\pm}0.57$ vs $0.93{\pm}0.16%$, p<0.005; $CD3^+$ HLA-$DR^+$: $16.92{\pm}3.89$ vs $3.94{\pm}0.70%$, p<0.005). 4) 환자군중 PPD에 대한 양성반응을 보인 군과 음성반응을 보인 군 사이에는 기관지 폐포세척액내의 임파구의 조성의 차이 및 수에서 차이가 없었다. 5) 환자군에서 PPD에 대한 피부반응과 기관지 폐포세척 세포의 조성비 사이에는 모두 상관관계가 없었으며, PPD에 대한 피부반응과 기관지 폐포세척액 및 말초 혈액내의 임파구아형의 조성과도 상관관계가 없었다. 결론 : 결론적으로 기관지 폐포세척액내의 염증 세포와 세포매개성 면역 반응과는 직접적인 관계가 없음을 알수 있었으며, 활동성 폐결핵 환자에서의 지연성 피부 반응의 저하는 임파구의 구획에 의한 결과라는 것을 배제할 수 없었다.

• 대한세포병리학회지
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• 제6권2호
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• pp.106-115
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• 1995

Reactive humsn mesothelial cells were examined by immunocytochemical stain with intermediate filaments (cytokeratin [CK1, CK7, CK8, CK18, CD19), vimentin, desmin, actin), epithelial membrane antigen, carcinoembryonic antigen (CEA), MHC class II antigen (HLA-DR), LeuM-1 (CD15), $\alpha1-antitrypsin$(ACT), $\alpha1-antichymotrypsin$ (ACHT), CD68(KP-1) and FcyRIII(CD16). The mesothelial cells were isolated from patients with liver cirrhosis and pleural effusion, and short-term cultured in RPMI 1640 media containing 10% heat inactivated fetal calf serum and 1% identical supernatant fluid of the patients' transudates. The results obtained are as follows 1. The cultured-reactive mesothelial cells were positive for the protein of cytoskeleton such as cytokeratin and vimentin, but negative for desmin and actin. The resting mesothelial cells showed positive reactions for cylokeratin, but negative for vimentin, desmin and actin. 2. The primary antibodies to the cytokeratin were strongly reactive for CK1, CK8 and CK18 but negative for CK7 and CK19 in both reactive and resting mesothelial cells. 3. Resting mesothelial cells showed negative reactions for CEA, but strong positive reactions in cultured-reactive mesothelial cells. 4. The markers for the monocytes/histiocytes(CD11b, CD14, CD16, CD68, Iysozyme and $\alpha1-antitrypsin$ and $\alpha1-antichymotrypsin$) were nonreactive in resting mesothelial cells, but lysozyme and $\alpha1-antitrypsin$ were weakly reactive in reactive and proliferative mesothelial cells. 5. MHC Class II molecule(HLA-DR antigen) was negative in both resting and reactive mesothelial cells. These results suggest that the short-term cultured, reactive mesothelial cells show a newly aberrant expression of the vimentin and calcine-embryonic antigen. The reason of the aberrant expression of the intermediate filament and oncofetal antigen in reactive and proliferative mesothelial cells should be further evaluated.

• Archives of Plastic Surgery
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• 제34권1호
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• pp.1-7
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• 2007

Purpose: Human adipose tissue-derived stromal cells(hADSCs) can be expanded in vitro and induced to differentiate into multiple mesenchymal cell types. In this study we have examined various neuronal phenotypes and gene expression profiles of the hADSCs in the neuronal induction. Methods: The hADSCs were isolated from human adipose tissue and they were characterized by the flow cytometry analysis using CD13, CD29, CD34, CD45, CD49d, CD90, CD105 and HLA-DR cell surface markers. We differentiated the hADSCs into the neuronal lineage by using chemical induction medium and observed the cells with contrast microscopy. The immunocytochemistry and western blotting were performed using the NSE, NeuN, Trk-A, Vimentin, N-CAM, S-100 and ${\beta}$-Tubulin III antibodies. Results: The hADSCs were positive for CD13($90.3{\pm}4%$), CD29($98.9{\pm}0.7%$), CD49d($13.6{\pm}6%$), CD90 ($99.4{\pm}0.1%$), CD105($96%{\pm}2.8%$) but negative for CD34, CD45 and HLA-DR. The untreated cultures of hADSCs predominately consisted of spindle shaped cells and a few large, flat cells. Three hours after the addition of induction medium, the hADSCs had changed morphology and adopted neuronal-like phenotypes. The result of immunocytochemistry and western blotting showed that NSE, NeuN, Trk-A, Vimentin, N-CAM, S-100 and ${\beta}$-Tubulin III were expressed. However, NSE, NeuN, Vimentin were weakly expressed in the control. Conclusion: Theses results indicate that hADSCs have the capabillity of differentiating into neuronal lineage in a specialized culture medium. hADSCs may be useful in the treatment of a wide variety of neurological disorders.

• 대한임상검사과학회지
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• 제40권2호
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• pp.106-112
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• 2008

Bone marrow derived mesenchymal stem cells (BMSCs) are largely studied for their potential clinical use. But it is hard to get enough number of those cells for clinical trials and give serious pain to the patients. Adipose tissue is derived from the embryonic mesenchyme and contains a stroma that is easily isolated with large amount. This cell population (adipose derived stem cells: ADSCs) can be isolated from human lipoaspirates and like MSCs, differentiate toward the osteogenic, adipogenic, myogenic and chondrogenic lineages. To confirm whether adipose tissue contains stem cells, the ADSCs extracted from omental or subcutaneous fat tissue were expanded during third to fifth passages. The phenotype of the ADSCs was identified by the conventional cell surface markers using flow cytometry: positive for CD29 and CD44, but negative for CD34, CD45, CD117 and HLA-DR that similar to those observed on BMSCs. The ADSCs were able to differentiate into the osteoblast or adipocytes with induction media. Finally, ADACs expressed multiple CD marker antigens similar to those observed on BMSCs and differentiated into osteoblast, adipocyte. With this, human adipotissue contains multipotent cells and may represent an alternative stem cell source to bone marrow-derived MSCs.

• 한국발생생물학회지:발생과생식
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• 제23권2호
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• pp.79-92
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• 2019

Humanized mice, containing engrafted human cells and tissues, are emerging as an important in vivo platform for studying human diseases. Since the development of Nod scid gamma (NSG) mice bearing mutations in the IL-2 receptor gamma chain, many investigators have used NSG mice engrafted with human hematopoietic stem cells (HSCs) to generate functional human immune systems in vivo, results in high efficacy of human cell engraftment. The development of NSG mice has allowed significant advances to be made in studies on several human diseases, including cancer and graft-versus-host-disease (GVHD), and in regenerative medicine. Based on the human HSC transplantation, organ transplantation including thymus and liver in the renal capsule has been performed. Also, immune reconstruction of cells, of the lymphoid as well as myeloid lineages, has been partly accomplished. However, crosstalk between pluripotent stem cell derived therapeutic cells with human leukocyte antigen (HLA) mis/matched types and immune CD3 T cells have not been fully addressed. To overcome this hurdle, human major histocompatibility complex (MHC) molecules, not mouse MHC molecules, are required to generate functional T cells in a humanized mouse model. Here, we briefly summarize characteristics of the humanized mouse model, focusing on development of CD3 T cells with MHC molecules. We also highlight the necessity of the humanized mouse model for the treatment of various human diseases.