• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권2호
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• pp.55-62
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• 2013

Bone tissue engineering is one of the important therapeutic approaches to the regeneration of bones in the entire field of regeneration medicine. Mesenchymal stem cells (MSCs) are actively discussed as material for bone tissue engineering due to their ability to differentiate into autologous bone. MSCs are able to differentiate into different lineages: osteo/odontogenic, adipogenic, and neurogenic. The tissue of origin for MSCs defines them as bone marrow-derived stem cells, adipose tissue-derived stem cells, and, among many others, dental stem cells. According to the tissue of origin, DSCs are further stratified into dental pulp stem cells, periodontal ligament stem cells, stem cells from apical papilla, stem cells from human exfoliated deciduous teeth, dental follicle precursor cells, and dental papilla cells. There are numerous in vitro/in vivo reports suggesting successful mineralization potential or osteo/odontogenic ability of MSCs. Still, there is further need for the optimization of MSCs-based tissue engineering methods, and the introduction of genes related to osteo/odontogenic differentiation into MSCs might aid in the process. In this review, articles that reported enhanced osteo/odontogenic differentiation with gene introduction into MSCs will be discussed to provide a background for successful bone tissue engineering using MSCs with artificially introduced genes.

• IMMUNE NETWORK
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• 제1권1호
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• pp.87-94
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• 2001

목적 : 제대혈의 조혈모세포 체외확장 시 조혈세포 증폭과 더불어 조혈미세환경의 변화가 일어난다. 이때 제대혈 $CD34^+$ 세포에서 유래되는 지지세포의 계열 분석조혈성장인자 분비능력을 알아보고 지지세포 증식 조건을 확립하여 효과적인 제대혈의 체외증폭을 제시하고자 하였다. 방법 : 제대혈부터 $CD34^+$ 세포를 분리하여 실험에 사용하였다. 무혈청배지에서 각종 조혈성장인자를 다양한 조합으로 첨가하여 배양하였고 증식정도는 현미경으로 관찰하여 배양용기를 점유한 면적 비율로 계산하였다. 세포외간질 단백의 효과를 분석하기 위하여 collagen S, fibronectin, laminin 및 poly-L-ly sine를 미리 coating한 용기에 배양하여 분석하였다. 제대혈 $CD34^+$ 세포를 조혈성장인자의 첨가 없이 3주간 액체배양하였다. 배양 시, 1주, 2주 및 3주에 상층액을 얻어 $-80^{\circ}C$에 보관하였다가 한꺼번에 IL-3, IL-6, GM-CSF, IL-$1{\beta}$ 및 TNF-$\alpha$등을 ELISA 방법으로 내부적으로 분비되는 량을 측정하였다. 분화된 지지세포의 계열을 분석하기 위해 E-selectin, VCAM-1, ICAM-1, PECAM-1, vWF, vimentin 및 CD 14 항체를 이용하여 면역화학염색 후 형광현미경으로 관찰하였다. 결과 : 제대혈 $CD34^+$ 세포 체외증폭시키는 과정에서 배양 4일에 지지세포가 출현하기 시작하여 7-10일이 지나면서 증식하기 시작하였고 14-2 1일 경에 서로 뭉치는 양상을 보여주었다. 제대혈 $CD34^+$ 세포 배양하면서 내부적으로 분비되는 GM-CSF, IL-6의 측정치는 시간이 지남에 따라 증가되었다. 제대혈 $CD34^+$ 세포 체외확장 시 지지세포의 증식 정도는 TPO+FL+SCF+LIF의 조합의 조혈성장인자가 첨가되었을 때 그리고 세포외간질 단백 성분 중 1% poly-L-lysine으로 처리한 경우 가장 효과적이었다. 결론 : 체외 증폭시 제대혈 $CD34^+$ 세포로부터 지지세포가 나타났으며 적절한 조혈성장인자의 첨가나 세포외간질 단백의 첨가에 의해 증폭될 수 있다.

• 한국수정란이식학회지
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• 제30권3호
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• pp.249-255
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• 2015

Diabetes mellitus, the most common metabolic disorder, is divided into two types: type 1 and type 2. The essential treatment of type 1 diabetes, caused by immune-mediated destruction of ${\beta}-cells$, is transplantation of the pancreas; however, this treatment is limited by issues such as the lack of donors for islet transplantation and immune rejection. As an alternative approach, stem cell therapy has been used as a new tool. The present study revealed that bone marrowderived mesenchymal stromal cells (BM-MSCs) could be transdifferentiated into pancreatic cells by the insertion of a key gene for embryonic development of the pancreas, the pancreatic and duodenal homeobox factor 1 (PDX1). To avoid immune rejection associated with xenotransplantation and to develop a new cell-based treatment, BM-MSCs from ${\alpha}$-1,3-galactosyltransferase knockout (GalT KO) pigs were used as the source of the cells. Transfection of the EGFP-hPDX1 gene into GalT KO pig-derived BM-MSCs was performed by electroporation. Cells were evaluated for hPDX1 expression by immunofluorescence and RT-PCR. Transdifferentiation into pancreatic cells was confirmed by morphological transformation, immunofluorescence, and endogenous pPDX1 gene expression. At 3~4 weeks after transduction, cell morphology changed from spindle-like shape to round shape, similar to that observed in cuboidal epithelium expressing EGFP. Results of RT-PCR confirmed the expression of both exogenous hPDX1 and endogenous pPDX1. Therefore, GalT KO pig-derived BM-MSCs transdifferentiated into pancreatic cells by transfection of hPDX1. The present results are indicative of the therapeutic potential of PDX1-expressing GalT KO pig-derived BM-MSCs in ${\beta}-cell$ replacement. This potential needs to be explored further by using in vivo studies to confirm these findings.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1519-1529
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• 2016

Background: Matrix metalloproteinase -2 (gelatinase-A, Mr 72,000 type IV collagenase, MMP-2) and -9 (gelatinase-B, Mr 92,000 type IV collagenase, MMP-9) are key molecules that play roles in tumor growth, invasion, tissue remodeling, metastasis and stem-cell regulation by digesting extracellular matrix barriers. MMP-2 and -9 are well known to impact on solid cancer susceptibility, whereas, in hematological malignancies, a paucity of data is available to resolve the function of these regulatory molecules in bone marrow mononuclear cells (BM-MNCs) and stromal cells of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Objectives: The present study aimed to investigate mRNA expression and gelatinase A and B secretion from BM-MNCs in vitro and genotypic associations of MMP-2 (-1306 C/T; rs243865), MMP-9 (-1562 C/T; rs3918242), tissue inhibitor of metalloproteinase -1 (TIMP-1) (372T/C; rs4898, Exon 5) and TIMP-2 (-418G/C; rs8179090) in MDS and AML. Results: The study covered cases of confirmed MDS (n=50), AML (n=32) and healthy controls (n=110). MMP-9 mRNA expression revealed 2 fold increased expression in MDS-RAEB II and 2.5 fold in AML M-4 (60-70% blasts). Secretion of gelatinase-B also revealed the MMP-9 mRNA expression and ELISA data also supported these data. We noted that those patients having more blast crises presented with more secretion of MMP-9 and its mRNA expression. In contrast MMP-9 (-1562 C/T) showed significant polymorphic associations in MDS (p<0.02) and AML (p<0.02). MMP-9 mRNA expression of C/T and T/T genotypes were 1.5 and 2.5 fold increased in MDS and AML respectively. In AML, MMP-2 C/T and T/T genotypes showed 2.0 fold mRNA expression. Only MMP-9 (-1306 C/T) showed significant 4 fold (p<0.001) increased risk with chemical and x-ray exposed MDS, while tobacco and cigarette smokers have 3 fold (p<0.04) risk in AML. Conclusions: In view of our results, MMP-9 revealed synergistic secretion and expression in blast crises of MDS and AML with 'gene' polymorphic effects and is significantly associated with increased risk with tobacco, cigarette and environmental exposure. Release and secretion of these enzymes may influence hematopoietic cell behavior and may be important in the clinical point of view. It may offer valuable tools for diagnosis and prognosis, as well as possible targets for the treatments.

• 통합자연과학논문집
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• 제12권4호
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• pp.133-141
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• 2019

Mesenchymal stem cells (MSCs) are known to differentiate into multiple lineages, making neurogenic differentiation an important target in the clinical field. In the present study, we induced the neurogenic differentiation of cells using histone deacetylase (HDAC) inhibitors and studied their mechanisms for further differentiation in vitro. We treated cells with the HDAC inhibitors, MS-275 and NaB; and found that the cells had neuron-like features such as distinct bipolar or multipolar morphologies with branched processes. The mRNA expressions encoding for NEFL, MAP2, TUJ1, OLIG2, and SYT was significantly increased following HDAC inhibitors treatment compared to without HDAC inhibitors; high protein levels of MAP2 and Tuj1 were detected by immunofluorescence staining. We examined the mechanisms of differentiation and found that the Wnt signaling pathway and downstream mitogen-activate protein kinase were involved in neurogenic differentiation of MSCs. Importantly, Wnt4, Wnt5a/b, and Wnt11 protein levels were highly increased after treatment with NaB; signals were activated through the regulation of Dvl2 and Dvl3. Interestingly, NaB treatment increased the levels of JNK and upregulated JNK phosphorylation. After MS-275 treatment, Wnt protein levels were decreased and GSK-3β was phosphorylated. In this cell, HDAC inhibitors controlled the non-canonical Wnt expression by activating JNK phosphorylation and the canonical Wnt signaling by targeting GSK-3β.

• Molecules and Cells
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• 제40권2호
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• pp.133-142
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• 2017

Previous studies have shown that bone marrow mesenchymal stromal cell (MSC) transplantation significantly improves the recovery of neurological function in a rat model of intracerebral hemorrhage. Potential repair mechanisms involve anti-inflammation, anti-apoptosis and angiogenesis. However, few studies have focused on the effects of MSCs on inducible nitric oxide synthase (iNOS) expression and subsequent peroxynitrite formation after hypertensive intracerebral hemorrhage (HICH). In this study, MSCs were transplanted intracerebrally into rats 6 hours after HICH. The modified neurological severity score and the modified limb placing test were used to measure behavioral outcomes. Blood-brain barrier disruption and neuronal loss were measured by zonula occludens-1 (ZO-1) and neuronal nucleus (NeuN) expression, respectively. Concomitant edema formation was evaluated by H&E staining and brain water content. The effect of MSCs treatment on neuroinflammation was analyzed by immunohistochemical analysis or polymerase chain reaction of CD68, Iba1, iNOS expression and subsequent peroxynitrite formation, and by an enzyme-linked immunosorbent assay of pro-inflammatory factors (IL-$1{\beta}$ and TNF-${\alpha}$). The MSCs-treated HICH group showed better performance on behavioral scores and lower brain water content compared to controls. Moreover, the MSC injection increased NeuN and ZO-1 expression measured by immunochemistry/immunofluorescence. Furthermore, MSCs reduced not only levels of CD68, Iba1 and pro-inflammatory factors, but it also inhibited iNOS expression and peroxynitrite formation in perihematomal regions. The results suggest that intracerebral administration of MSCs accelerates neurological function recovery in HICH rats. This may result from the ability of MSCs to suppress inflammation, at least in part, by inhibiting iNOS expression and subsequent peroxynitrite formation.

• 생명과학회지
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• 제17권5호
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• pp.678-686
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• 2007

인간중간엽줄기세포는(Human mesenchymal stem cells, hMSC) 골수, 지방, 피부, 근육, 혈액에 존재하며, 뼈, 연골, 지방, 근육, 신경세포로 분화가능성이 보고되어 손상조직의 재생을 위한 재료로서뿐만 아니라 유전자치료의 매개체로 이용될 수 있는 가능성이 제안되고 있다. 인간중간엽줄기세포의 적절한 배양조건에는 소 태아혈청(fetal bovine serum, FBS)이 요구되어지므로 세포치료에는 소 태아혈청이 다수 포함되어 있을 것이며 세포배양 배지 유래 소 태아혈청의 단백질에 의한 면역거부반응이 우려된다. 이미 앞선 연구에서 자가혈청 하에서 인체지방줄기세포 분리와 계속적인 세포배양을 실시하였을 때 인체지방줄기세포의 증식능력과 다 분화 능이 유지되며 면역결핍 생쥐에 골수의 말초혈액에서 유래된 CD34세포 이식 시 안착 능을 촉진함을 보였다. 본 연구에서 인체지방줄기세포가 인체혈청 하에서 배양되었을 때 소 태아혈청 하에서 배양할 때 발현하는 표면항원을 유지함을 확인했으며 microarray를 사용하여 유전자 발현을 비교했다. 유 세포 분석을 통하여 인체혈청 하에서 계속적으로 배양된 인체유래지방줄기세포에서 HLA-DR, CD117, CD29 와 CD44 의 발현이 소 태아혈청 하에서 배양했을 때와 비슷함을 밝혔다. 그러나 인체혈청 하에서 배양된 인체지방줄기세포의 유전자 발현형태와 소 태아혈청 하에서 배양된 세포의 유전자 발현형태 간에는 상당한 차이를 보였다. 그러므로 본 연구는 인체혈청 하에서 배양된 인체지방기질줄기세포가 임상적용을 위한 선행 데이터로써 직접적인 추정을 하기 위해서는 인체지방기질줄기세포 이식연구에 in vivo 동물실험연구가 수행되어져야 함을 제시하고 있다.

• 폴리머
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• 제30권3호
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• pp.196-201
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• 2006

온도감응성 고분자인 폴리 (에틸렌 글리콜)을 기본으로 하는 다이블록 및 트리블록 폴리에스테르 공중합체들은 비독성과 생체적합성 그리고 생분해성 특징 때문에 조직공학 분야 및 주사제형의 약물전달체에서 많은 응용이 이루어지고 있다. 본 연구에서는 다이블록 공중합체를 이용한 솔-젤 전이 현상을 갖는 고분자를 평균분자량 750 g/mole의 메톡시 폴리 (에틸렌 글리콜)과 카프로락톤을 실온에서 HCl $Et_2O$ 존재 하에서 개환중합을 통하여 합성하였다. 이 공중합체를 이용하여 in vivo상에서 골수간엽줄기세포와 골유도물질인 덱사메타손의 존재 여부에 따라 골분화의 가능성을 조사하였다. 조직을 파라핀으로 고정시켜 슬라이드를 제조한 후 hematoxylin & eosin, 본쿠사 및 오스테오칼신 염색을 통하여 골형성 정도를 확인하였다. 결론적으로 덱사메타손이 함유된 젤이 골형성에 도움을 주지만 젤만으로는 강한 골형성을 유도할 수 없으므로 줄기세포나 다른 골형성 유도재료를 사용하면 우수하게 골형성 효과를 가져올 것이라고 판단되었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권3호
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• pp.217-224
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• 2008

Angiogenesis plays an important role in bone development and postnatal bone fracture repair. Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) have been thought to be primarily involved in promoting angiogenesis. It is well known that VEGF and its receptors have been reported to play an important role in the regulation of the interaction between angiogenesis and osteogenesis during bone repair processes. Dexamethasone, a potent synthetic glucocorticoid, promotes phenotype markers of osteoblast differentiation, such as ALP and osteocalcin. It stimulates in vitro osteogenesis of human bone marrow osteogenic stromal cells. Dexamethasone has been reported to suppress VEGF gene expression in some cells. However, our previous study demonstrated VEGF quantification increased in a time-dependent manner in periosteal-derived osteogenesis under dexamethasone. So, the purpose of this study was to examine the angiogenic phenotypes in cultured human periosteal-derived cells under high-dose dexamethasone. Periosteal-derived cells were cultured using a technique previously described. After passage 3, the periosteal-derived cells were further cultured for 28 days in an osteogenic inductive culture medium containing ascorbic acid, ${\beta}$-glycerophosphate and high-dose dexamethasone, We evaluated the expression of VEGF isoforms, VEGFR-1, VEGFR-2, and neuropilin-1, ALL VEGF isoforms ($VEGF_{121},\;VEGF_{165},\;VEGF_{189}$, and $VEGF_{206}$) expression was observed by RT-PCR analysis. VEGFR-1, VEGFR-2 and neuropilin-1 expression increased up to day 14, particularly during the early stage of mineralization. Our results suggest the involvement of direct VEGFs/VEGFRs system on periosteal-derived cells during early mineralization phase under high-dose of dexamethasone. These also suggest that VEGF might act as an autocrine growth molecule during osteoblastic differentiation of cultured human periosteal-derived cells.

• BMB Reports
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• 제44권10호
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• pp.686-691
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• 2011

Granulocyte colony-stimulating factor (G-CSF) is a cytokine secreted by stromal cells and plays a role in the differentiation of bone marrow stem cells and proliferation of neutrophils. Therefore, G-CSF is widely used to reduce the risk of serious infection in immunocompromised patients; however, its use in such patients is limited because of its non-persistent biological activity. We created an N-linked glycosylated form of this cytokine, hG-CSF (Phe140Asn), to assess its biological activity in the promyelocyte cell line HL60. Enhanced biological effects were identified by analyzing the JAK2/STAT3/survivin pathway in HL60 cells. In addition, mutant hG-CSF (Phe140Asn) was observed to have enhanced chemoattractant effects and improved differentiation efficiency in HL60 cells. These results suggest that the addition of N-linked glycosylation was successful in improving the biological activity of hG-CSF. Furthermore, the mutated product appears to be a feasible therapy for patients with neutropenia.