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Kim J.,CHA Bio and Diostech Co. | Shin J.M.,CHA Bio and Diostech Co. | Jeon Y.J.,Chonbuk National University | Chung H.M.,CHA Bio and Diostech Co. | And 2 more authors.
PLoS ONE | Year: 2012

Mesenchymal stem cells (MSCs) are one of the most attractive therapeutic resources in clinical application owing to their multipotent capability, which means that cells can differentiate into various mesenchymal tissues such as bone, cartilage, fat, tendon, muscle and marrow stroma. Depending on the cellular source, MSCs exhibit different application potentials according to their different in vivo functions, despite similar phenotypic and cytological characteristics. To understand the different molecular conditions that govern the different application or differentiation potential of each MSC according to cellular source, we generated a proteome reference map of MSCs obtained from bone marrow (BM), umbilical cord blood (CB) and peripheral blood (PB). We identified approximately 30 differentially regulated (or expressed) proteins. Most up-regulated proteins show a cytoskeletal and antioxidant or detoxification role according to their functional involvement. Additionally, these proteins are involved in the increase of cell viability, engraftment and migration in pathological conditions in vivo. In summary, we examined differentially expressed key regulatory factors of MSCs obtained from several cellular sources, demonstrated their differentially expressed proteome profiles and discussed their functional role in specific pathological conditions. With respect to the field of cell therapy, it may be particularly crucial to determine the most suitable cell sources according to target disease. © 2012 Kim et al.

Park J.S.,CHA Medical University | Shim M.-S.,CHA Medical University | Shim S.H.,CHA Medical University | Yang H.N.,CHA Medical University | And 5 more authors.
Biomaterials | Year: 2011

In this study, several types of hMSCs, derived from bone marrow, adipose tissue, or amniotic fluid, were encapsulated in a fibrin hydrogel mixed with TGF-β3 and then evaluated for their capacity for differentiation in vitro and in vivo. For determination of stem cell differentiation, RT-PCR, real time quantitative PCR (qPCR), histology, and immunohistochemical assays were used for analysis of chondrogenesis. Using these analysis methods, several of the cultured hMSCS were found to highly express genes and proteins specific to cartilage forming tissues. Additionally, similar trends in expression were found in tissue recovered from nude mice transplanted with several types of hMSCs encapsulated in a fibrin hydrogel containing TGF-β3. The results of both in vitro and in vivo analyses showed that cultured or transplanted hMSCs mixed with TGF-β3 in a fibrin hydrogel differentiated into chondrocytes, suggesting that these cells would be suitable for reconstruction of hyaline articular cartilage. © 2011 Elsevier Ltd.

Lee H.-J.,CHA Bio and Diostech Co. | Cha K.E.,CHA Medical University | Hwang S.-G.,Korea University | Kim J.K.,Korea University | Kim G.J.,CHA Medical University
Journal of Cellular Biochemistry | Year: 2011

Stem cells have unique properties such as self-renewal, plasticity to generate various cell types, and availability of cells of human origin. The characteristics are attentive in the toxicity screening against chemical toxicants. Placenta-derived stem cells (PDSCs) have been spotlighted as a new cell source in stem cell research recently because they are characterized by their capacity to differentiate into multilineages. However, the use of PDSCs as an in vitro screening model for potential drug candidates has not yet been studied. Here, we analyzed the potentials for bone-marrow-derived mesenchymal stem (BM-MSCs), which is a representative adult stem cells and PDSCs as an in vitro hepatotoxicity screening system, using well-known hepatotoxicants. BM-MSCs and PDSCs were analyzed to the potential for hepatogenic differentiation and were cultured with different concentrations of hepatotoxicants for time courses. The viability and ATP-binding cassette (ABC) transporters were measured by the MTT assay and RT-PCR, respectively. The sensitivities of PDSCs to hepatotoxicants are more sensitive than those of BM-MSCs. The viability (IC 50) to in PDSCs was less than that of BM-MSCs after 48 and 72 h (P<0.05) of CCl4 exposure. The toxicities of CCl4 were decreased by fourfold in hepatogenic differentiation inducing PDSCs compared to the undifferentiated cells. The alteration of ABCGs was observed in PDSCs during differentiation. These findings suggest that the naïve PDSCs expressing ABCGs can be used as a source for in vitro screening system as well as the expression patterns of ABCG1 and ABCG2 might be involved in the sensitivity of PDSCs to hepatotoxicants. © 2010 Wiley-Liss, Inc.

Park S.G.,CHA Medical University | Kim J.H.,CHA Medical University | Kim J.H.,CHA Bio and Diostech Co. | Xia Y.,University of Houston | Sung J.-H.,CHA Medical University
Expert Opinion on Therapeutic Targets | Year: 2011

Introduction: Reactive oxygen species (ROS) participate in cellular apoptosis and are involved in pathophysiological etiology of degenerative diseases. However, recent studies suggest that ROS at low levels may play a pivotal role as second messengers and activate normal cellular processes. Intracellular ROS increase the proliferation, migration, and regenerative potential of adipose-derived stem cells (ASCs). In contrast, manipulations that diminish intracellular ROS levels interfere with normal ASC function. ROS generation therefore acts like a double-edged sword. Areas covered: This review discusses the following research questions: i) Do ROS stimulate or suppress ASCs? ii) How are ROS generated from ASCs? iii) Which function(s) is/are regulated by intracellular ROS generation? In addition, the antioxidant/ antiapoptotic effect of ASCs is briefly introduced. Expert opinion: Whether ROS is harmful or beneficial is primarily a question of dosage. Low or moderate ROS generation increases the proliferation, migration and regenerative potential of ASCs. Therefore, it is beneficial to expose ASCs to moderate oxidative stress during manipulation. The addition of a ROS donor in culture can reduce the cost for the expansion of ASCs and a ROS preconditioning can enhance the regenerative potential of ASCs. © 2011 Informa UK, Ltd.

Moon S.-H.,Konkuk University | Ju J.,Korea University | Park S.-J.,Konkuk University | Bae D.,CHA Bio and Diostech Co. | And 2 more authors.
Biomaterials | Year: 2014

Human embryonic stem cells (hESCs) are generally induced to differentiate by forming spherical structures termed embryoid bodies (EBs) in the presence of soluble growth factors. hEBs are generated by suspending small clumps of hESC colonies; however, the resulting hEBs are heterogeneous because this method lacks the ability to control the number of cells in individual EBs. This heterogeneity affects factors that influence differentiation such as cell-cell contact and the diffusion of soluble factors, and consequently, the differentiation capacity of each EB varies. Here, we fabricated size-tunable concave microwells to control the physical environment, thereby regulating the size of EBs formed from single hESCs. Defined numbers of single hESCs were forced to aggregate and generate uniformly sized EBs with high fidelity, and the size of the EBs was controlled using concave microwells of different diameters. Differentiation patterns in H9- and CHA15-hESCs were affected by EB size in both the absence and presence of growth factors. By screening EB size in the presence of various BMP4 concentrations, a two-fold increase in endothelial cell differentiation was achieved. Because each hESC line has unique characteristics, the findings of this study demonstrate that concave microwells could be used to screen different EB sizes and growth factor concentrations to optimize differentiation for each hESC line. © 2014 Elsevier Ltd.

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