• Animal cells and systems
• /
• v.15 no.1
• /
• pp.19-27
• /
• 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.

• Proceedings of the KSME Conference
• /
• 2008.11a
• /
• pp.1419-1426
• /
• 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
• /
• v.19 no.3
• /
• pp.210-214
• /
• 2004

Whole liver transplantation, the currently available treatment of end-stage liver disease, has limitations including serious donor shortage, fatal surgical complications, risk of allograft rejection, and the requirement of life-long immunosuppression. In this study, we investigated the possibility of reconstructing liver tissues in vivo by implanting fetal hepatocytes on polymer scaffolds as a potential method to replace the current treatments. Fetal hepatocytes were freshly isolated from mice and seeded onto porous mesh scaffolds fabricated from polyglycolic acid, a biodegradable synthetic polymer. The seeded scaffolds were implanted into peritoneal cavity of athymic mice for one week. As a control, fetal hepatocytes were implanted without scaffold. One week after transplantation, liver-like tissues formed. Histological and immunohistochemical analyses indicated that the hepatocyles and liver tissue structures (bile ducts) were present in the newly formed tissues. In the control group, no transplanted hepatocytes were observed. Theses preliminary results suggest that liver tissues may be regeneration by transplanting fetal hepatocytes on polymer scaffolds.

• IMMUNE NETWORK
• /
• v.15 no.2
• /
• pp.66-72
• /
• 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
• /
• v.29 no.1
• /
• pp.58-66
• /
• 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
• /
• v.17 no.3
• /
• pp.219-240
• /
• 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
• /
• v.30 no.5
• /
• pp.391-398
• /
• 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
• /
• v.24 no.3
• /
• pp.260-267
• /
• 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.

• Korean Journal of Clinical Laboratory Science
• /
• v.51 no.3
• /
• pp.370-378
• /
• 2019

The hepatic ischemic model has recently been widely used for the epidemiological study of ischemic reperfusion injury. This study was carried out to investigate the protective effect of vanillin, which is known to have antioxidant and anti-inflammatory effects, against hepatic and renal injury using an ischemia-reperfusion rat model, and we also investigated the mechanism related to vanillins' protective effect. The test material was administered at a concentration of 100 mg/kg for 3 days, followed by ligation of the liver for 60 minutes to induce ischemia reperfusion. As control groups, there was a negative control, sham control and ischemia-reperfusion-only ischemia reperfusion control, and the controls groups were compared with the drug administration group. In the vanillin group, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were significantly inhibited compared with the AST and ALT activities of the ischemia-reperfusion group, and histopathological examination showed significant reduction of both inflammation and necrosis. The malondialdehyde (MDA) and superoxide dismutase (SOD) levels were significantly different from the ischemia-reperfusion group. In conclusion, vanillin showed a hepatocyte protective action by alleviating the cellular inflammation and cell necrosis caused by hepatic ischemia-reperfusion, and vanillin mitigated inflammatory changes in the kidney glomeruli and distal tubules. The protective effect is considered to be caused by vanillin's antioxidant function. Further studies such as on cell death and possibly vanillin's same effect on damaged tissue will be necessary for clinical applications such as organ transplantation.