• Animal cells and systems
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• 제15권1호
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• pp.19-27
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• 2011

Hepatocytes, the major epithelial cells of the liver, maintain their morphology in culture dishes coated with extracellular matrix (ECM) components such as collagen and fibronectin or biodegradable polymers (e.g. chitosan, gelatin). In these coated dishes, survival of cells and maintaining of liver-specific functions may increase. The aim of this study was to determine a suitable, cost-effective and simple system for hepatocyte isolation and culture which may be useful for various applications such as in vitro toxicology studies, hepatocyte transplantation and bioartificial liver (BAL) systems. In order to obtain primary cultures, hepatocytes were isolated from liver by an enzymatic method and cultured on plates coated with collagen, chitosan or gelatin. Collagen, gelatin-sandwich and gelatin-cell mixture methods were also evaluated. Morphology and attachment of the cells were observed by inverted microscope and scanning electron microscope (SEM). An MTT assay was used to determine cell viability and mitochondrial activity.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1419-1426
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• 2008

Fulminant hepatic failure is a clinical syndrome associated with a high mortality rate. Orthotopic liver transplantation is the only clinically proven effective treatment for patients with end-stage liver disease who do not respond to medical management. A major limitation of this treatment modality is the scarcity of donor organs available, resulting in patients dying while waiting for a donor liver. An extracorporeal bioartificial liver (BAL) device containing viable hepatocytes has the potential to provide temporary hepatic support to liver failure patients, serving as a bridge to transplantation while awaiting a suitable donor. In some patients, providing temporary hepatic support may be sufficient to allow adequate regeneration of the host liver, thereby eliminating the need for a liver transplant. Although the BAL device is a promising technology for the treatment of liver failure, there are several technical challenges that must be overcome in order to develop systems with sufficient processing capacity and of manageable size. In this overview, the authors describe the critical issues involved in developing a BAL device. They also discuss their experiences in hepatocyte culture optimization within the context of a microchannel flat-plate BAL device.

• KSBB Journal
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• 제19권3호
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• pp.210-214
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• 2004

본 연구에서는 생분해성 고분자 담체인 PGA 담체에 부착된 간세포의 이식을 통해서 이식된 간세포가 괴사하지 않고 남아 있으며 간 조직 구조의 일종인 담세관 유사구조를 확인하였다. 조직공학적인 간세포 이식 방법의 개발은 간 질환에 새로운 치료방법 개발의 가능성을 열어줄 수 있다.

• IMMUNE NETWORK
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• 제15권2호
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• pp.66-72
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• 2015

Currently, detecting biochemical differences before and after allogeneic stem cell transplantation (SCT) for improved prediction of acute graft-versus-host disease (aGVHD) is a major clinical challenge. In this pilot study, we analyzed the kinetics of circulating adipokine levels in patients with or without aGVHD before and after allogeneic SCT. Serum samples were obtained and stored at $-80^{\circ}C$ within 3 hours after collection, prior to conditioning and at engraftment after transplantation. A protein array system was used to measure the levels of 7 adipokines of patients with aGVHD (n=20) and without aGVHD (n=20). The resistin level at engraftment was significantly increased (p<0.001) after transplantation, regardless of aGVHD occurrence. In the non-aGVHD group, the concentrations of the hepatocyte growth factor (HGF) (mean values${\pm}$SD; $206.6{\pm}34.3$ vs. $432.3{\pm}108.9pg/ml$, p=0.040) and angiopoietin-2 (ANG-2) (mean values${\pm}$SD; $3,197.2{\pm}328.3$ vs. $4,471.8{\pm}568.4pg/ml$, p=0.037) at engraftment were significantly higher than those of the pre-transplant period, whereas in the aGVHD group, the levels of adipokines did not change after transplantation. Our study suggests that changes in serum HGF and ANG-2 levels could be considered helpful markers for the subsequent occurrence of aGVHD.

• KSBB Journal
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• 제29권1호
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• pp.58-66
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• 2014

Demand for in vitro pharmacological evaluation and toxicity test using human hepatocytes has been increasing. In USA and Europe, human hepatocytes obtained from donated whole liver unsuitable for transplantation were distributed to researchers and deposited in cell bank facility as cryopreserved vial. In Korea, however, incidence of transplantation- inappropriate whole liver has been quite low and the whole livers almost have so severe liver disease such as fatty or fibrotic liver that cannot meet the demand. In this study we aimed to isolate human hepatocytes from liver resection surgery-originated partial liver, and assure the isolated human hepatocytes and its cryopreserved hepatocytes to be qualified for the in vitro pharmacological evaluation and drug toxicity tests. We compared those with commercially available human hepatocyte, BD $GenTest^{TM}$ by cell morphology, hepatic gene expression, urea synthesis, albumin secretion, ammonia removal, and cytochrome P450 induction activities. Changes in hepatotoxic gene expression after cryopreservation are evaluated with a typical hepatotoxic drug, acetaminophen. Consequently, the fresh hepatocytes from the partial liver and its cryopreserved hepatocytes expressed their intrinsic hepatic functions well and showed equal hepatotoxicity gene expression trend regardless to cryopreservation. Therefore, liver resection surgery-originated partial liver can be used as a useful source of human hepatocytes for various pharmacological and hepatotoxicity test.

• Biomolecules & Therapeutics
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• 제17권3호
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• pp.219-240
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• 2009

Since NF-${\kappa}B$ has been identified as a transcription factor associated with immune cell activation, groups of researchers have dedicated to reveal detailed mechanisms of nuclear factor of ${\kappa}B$ (NF-${\kappa}B$) in inflammatory signaling for decades. The various molecular components of NF-${\kappa}B$ transcription factor pathway have been being evaluated as important therapeutic targets due to their roles in diverse human diseases including inflammation, cystic fibrosis, sepsis, rheumatoid arthritis, cancer, atherosclerosis, ischemic injury, myocardial infarction, osteoporosis, transplantation rejection, and neurodegeneration. With regards to new drugs directly or indirectly modulating the NF-${\kappa}B$ pathway, FDA recently approved a proteasome inhibitor bortezomib for the treatment of multiple myeloma. Many pharmaceutical companies have been trying to develop new drugs to inhibit various kinases in the NF-${\kappa}B$ signaling pathway for many therapeutic applications. However, a gene knock-out study for $IKK{\beta}$ in the NF-${\kappa}B$ pathway has given rise to controversies associated with efficacy as therapeutics. Mice lacking hepatocyte $IKK{\beta}$ accelerated cancer instead of preventing progress of cancer. However, it is clear that pharmacological inhibition of $IKK{\beta}$ appears to be beneficial to reduce HCC. This article will update issues of the NF-${\kappa}B$ pathway and inhibitors regulating this pathway.

• Biomolecules & Therapeutics
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• 제30권5호
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• pp.391-398
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• 2022

Polyploidization is a process by which cells are induced to possess more than two sets of chromosomes. Although polyploidization is not frequent in mammals, it is closely associated with development and differentiation of specific tissues and organs. The liver is one of the mammalian organs that displays ploidy dynamics in physiological homeostasis during its development. The ratio of polyploid hepatocytes increases significantly in response to hepatic injury from aging, viral infection, iron overload, surgical resection, or metabolic overload, such as that from non-alcoholic fatty liver diseases (NAFLDs). One of the unique features of NAFLD is the marked heterogeneity of hepatocyte nuclear size, which is strongly associated with an adverse liver-related outcome, such as hepatocellular carcinoma, liver transplantation, and liver-related death. Thus, hepatic polyploidization has been suggested as a potential driver in the progression of NAFLDs that are involved in the control of the multiple pathogenicity of the diseases. However, the importance of polyploidy in diverse pathophysiological contexts remains elusive. Recently, several studies reported successful improvement of symptoms of NAFLDs by reducing pathological polyploidy or by controlling cell cycle progression in animal models, suggesting that better understanding the mechanisms of pathological hepatic polyploidy may provide insights into the treatment of hepatic disorders.

• Biomolecules & Therapeutics
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• 제24권3호
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• pp.260-267
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• 2016

Mesenchymal stem cells (MSCs) offer significant therapeutic promise for various regenerative therapies. However, MSC-based therapy for injury exhibits low efficacy due to the pathological environment in target tissues and the differences between in vitro and in vivo conditions. To address this issue, we developed adipose-derived MSC spheroids as a novel delivery method to preserve the stem cell microenvironment. MSC spheroids were generated by suspension culture for 3 days, and their sizes increased in a time-dependent manner. After re-attachment of MSC spheroids to the plastic dish, their adhesion capacity and morphology were not altered. MSC spheroids showed enhanced production of hypoxia-induced angiogenic cytokines such as vascular endothelial growth factor (VEGF), stromal cell derived factor (SDF), and hepatocyte growth factor (HGF). In addition, spheroid culture promoted the preservation of extracellular matrix (ECM) components, such as laminin and fibronectin, in a culture time- and spheroid size-dependent manner. Furthermore, phosphorylation of AKT, a cell survival signal, was significantly higher and the expression of pro-apoptotic molecules, poly (ADP ribose) polymerase-1 (PARP-1) and cleaved caspase-3, was markedly lower in the spheroids than in MSCs in monolayers. In the murine hindlimb ischemia model, transplanted MSC spheroids showed better proliferation than MSCs in monolayer. These findings suggest that MSC spheroids promote MSC bioactivities via secretion of angiogenic cytokines, preservation of ECM components, and regulation of apoptotic signals. Therefore, MSC spheroid-based cell therapy may serve as a simple and effective strategy for regenerative medicine.

• 대한임상검사과학회지
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• 제51권3호
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• pp.370-378
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• 2019

허혈 재관류 손상은 기관 이식, 외과적 혈관 재개통 및 출혈시에 발생하며 조직 및 기관 기능 장애를 유발한다. 최근 허혈 재관류 손상의 기전적 연구를 위해 간장 허혈 모델을 많이 이용하고 있다. 본 연구는 허혈 재관류 랫드 모델을 이용하여 항산화와 항염증 효과를 가진 것으로 알려진 Vanillin에 의한 간장 및 신장 손상에 대한 보호 효과를 알아보고 관련된 기전을 조사하기 위하여 실시하였다. 시험물질은 각각 100 mg/kg의 농도로 3일간 투여한 후, 60분동안 간을 결찰하여 허혈 재관류를 유도하여 관찰하였으며, 음성대조군, sham대조군 및 허혈재관류만 실시한 허혈 재관류대조군을 따로 두어, 약물투여군과 비교하였다. Vanillin 처치군에서는 AST, ALT 활성이 허혈 재관류대조군에 비해 유의하게 억제되었고, 조직병리학적 관찰에서도 염증 부분과 괴사부분이 현저하게 감소하였다. MDA와 SOD는 허혈 재관류군에 비해 유의적인 변화를 보였다. 이상의 결과를 종합하면 Vanillin은 간장 허혈 재관류에 의한 세포염증 및 세포괴사를 완화시켜 간세포 보호작용을 나타내었고, 신장의 사구체 및 원위세뇨관에 염증 변화를 완화 시키고 있어 세포 손상을 방어하는 것으로 생각되며, 이러한 방어효과는 항산화 기능에 의한 영향으로 사료된다.