Pluripotency of human embryonic stem cell (hESC) is one of the most valuable ability of hESCs for applying cell therapy field, but also showing side effect, for example teratoma formation. When transplant multipotent stem cell, such as mesnchymal stem cell (MSC) which retains similar differentiation ability, they do not form teratoma in vivo, but there exist limitation of cellular source supply. Accordingly, differentiation of hESC into MSC will be promising cellular source with strong points of both hESC and MSC line. In this study, we described the derivation of MSC like cell population from feeder free cultured hESC (hESC- MSC) using direct differentiation system. Cells population, hESC-MSC and bone marrow derived MSC (BM-MSC) retained similar characteristics in vitro, such as morphology, MSC specific marker expression and differentiation capacity. At the point of differentiation of both cell populations, differentiation rate was slower in hESC-MSC than BM-MSC. As these reason, to verify differentially expressed molecular condition of both cell population which bring out different differentiation rate, we compare the molecular condition of hESC-MSC and BM-MSC using 2-D proteomic analysis tool. In the proteomic analysis, we identified 49 differentially expressed proteins in hESC-MSC and BM-MSC, and they involved in different biological process such as positive regulation of molecular function, biological process, cellular metabolic process, nitrogen compound metabolic process, macromolecule metabolic process, metabolic process, molecular function, and positive regulation of molecular function and regulation of ubiquitin protein ligase activity during mitotic cell cycle, cellular response to stress, and RNA localization. As the related function of differentially expressed proteins, we sought to these proteins were key regulators which contribute to their differentiation rate, developmental process and cell proliferation. Our results suggest that the expressions of these proteins between the hESC-MSC and BM-MSC, could give to us further evidence for hESC differentiation into the mesenchymal stem cell is associated with a differentiation factor. As the initial step to understand fundamental difference of hESC-MSC and BM-MSC, we sought to investigate different protein expression profile. And the grafting of hESC differentiation into MSC and their comparative proteomic analysis will be positively contribute to cell therapy without cellular source limitation, also with exact background of their molecular condition.

Cardiovascular diseases (CVDs) are one of the most cause of death around the world and fields of interest for cardiac stem cells. Also, current use of terminally differentiated adult cardiomyocytes for CVDs has limited regenerative capacity therefore any significant cell loss may result in the development of progressive heart failure. Human embryonic stem cells (hESCs) derived from blastocyst‐stage embryos spontaneously have ability to differentiate via embryo‐like aggregates (endoderm, ectoderm and mesoderm) in vitro into various cell types including cardiomyocyte. However, most effective molecule or optimized condition which can induce cardiac differentiation of hESCs is rarely studied. In this study, we developed both spontaneous and inductive cardiomyocyte‐like cells differentiation from hESCs by treatment of induced‐factors, 5‐azacytidine, BMP‐4 and cardiogenol C. On the one hand, spontaneous and inductive cardiomyocyte‐like cells showed that cardiac markers are expressed for further analysis by RT‐PCR and immunocytochemistry. Interestingly, BMP‐4 greatly improved mogeneous population of the cardiomyocyte‐like cells from hESCs CHA15 and H09. In conclusion, we verified that spontaneously differentiated cells showed cardiac specific markers which characterize cardiac cells, treated extrinsic factors can manage cellular signals and found that hESCs can undergo differentiation into cardiomyocytes better than spontaneous group. This finding offers an insight into the inductive factor of differentiated cardiomyocytes and provides some helpful information that may offer the potential of cardiomyocytes derived from hESCs using extrinsic factors.

Hepatocytes derived from human embryonic stem cells (hESCs) may be a useful source for the treatment of diseased or injured liver. However, a low survival rate of grafted hepatocytes and immune rejection are still major obstacles to be overcome. We previously showed that secreted proteins (secretome) from hESC-derived hepatocytes had a potential therapeutic power in the tissue repair of injured liver without cell transplantation. The purpose of the present study was to discover key protein(s) in the secretome of hESC-derived hepatocytes using proteomic analysis and to study the tissue repair mechanism which may be operated by the secretomes. Purified indocyanine green+ hepatocytes derived from hESCs displayed multiple hepatic features, including expression of hepatic genes, production of albumin, and glycogen accumulation. The nano-LC/ESI-QTOF-MS analysis identified 365 proteins in the secretome of hESC-derived hepatocytes and the protein functional network analysis was conducted using the MetaCore TM from GeneGO. In addition, 20 tissue regeneration-related transcription factors (TFs) were extrapolated through further proteomic analysis. After intraperitoneal injection, the secretome significantly promoted the liver regeneration in a mouse model of acute liver injury. Protein functional network analysis on the secretome-induced regenerating liver confirmed 20 transcription factors (TFs) which were identified in the ICGhigh cells. The upreguation of these tissue repair-related TFs were validated by qPCR and western blotting on the regenerating liver tissues. These results demonstrate that application of the secretome analysis in combination with the protein functional network mapping would provide a reliable tool to discover new tissue-regenerating proteins as well as to expand our knowledge of the mechanisms of tissue regeneration.