Generation of Hepatic Progenitor Cells from the Primary Hepatocytes of Nonhuman Primates Using Small Molecules

BACKGROUND@#Since primates have more biological similarities to humans than do other animals, they are a valuable resource in various field of research, including biomedicine, regenerative medicine, and drug discovery. However, there remain limitations to maintenance and expansion of primary hepatocytes derived from nonhuman primates. To overcome these limitations, we developed a novel culture system for primate cells. @*METHODS@#Primary hepatocytes from Macaca fascicularis (mf-PHs) were isolated from hepatectomized liver. To generate chemically derived hepatic progenitor cells (mf-CdHs), mf-PHs were cultured with reprogramming medium containing A83-01, CHIR99021, and hepatocyte growth factor (HGF). The bi-potent differentiation capacity of mf-CdHs into hepatocytes and biliary epithelial cells was confirmed by treatment with hepatic differentiation medium (HDM) and cholangiocytic differentiation medium (CDM), respectively. @*RESULTS@#mf-PHs cultured with reprogramming medium showed rapid proliferation capacity in vitro and expressed progenitor-specific markers. Moreover, when cultured in HDM, these progenitor cells stably differentiated into hepatocytelike cells expressing the mature hepatic markers. On the other hand, when cultured in CDM, the differentiated biliary epithelial cells expressed mature cholangiocyte characteristics. @*CONCLUSION@#The results of the present study demonstrate that we successfully induced the formation of hepatic progenitor cells from mf-PHs by culturing them with a combination of small molecules, including growth factors. These results offer a means of expanding nonhuman primate hepatocytes without genetic manipulation for cellular resource, preclinical applications and regenerative medicine for the liver.

Generation of Hepatic Progenitor Cells from the Primary Hepatocytes of Nonhuman Primates Using Small Molecules

BACKGROUND@#Since primates have more biological similarities to humans than do other animals, they are a valuable resource in various field of research, including biomedicine, regenerative medicine, and drug discovery. However, there remain limitations to maintenance and expansion of primary hepatocytes derived from nonhuman primates. To overcome these limitations, we developed a novel culture system for primate cells. @*METHODS@#Primary hepatocytes from Macaca fascicularis (mf-PHs) were isolated from hepatectomized liver. To generate chemically derived hepatic progenitor cells (mf-CdHs), mf-PHs were cultured with reprogramming medium containing A83-01, CHIR99021, and hepatocyte growth factor (HGF). The bi-potent differentiation capacity of mf-CdHs into hepatocytes and biliary epithelial cells was confirmed by treatment with hepatic differentiation medium (HDM) and cholangiocytic differentiation medium (CDM), respectively. @*RESULTS@#mf-PHs cultured with reprogramming medium showed rapid proliferation capacity in vitro and expressed progenitor-specific markers. Moreover, when cultured in HDM, these progenitor cells stably differentiated into hepatocytelike cells expressing the mature hepatic markers. On the other hand, when cultured in CDM, the differentiated biliary epithelial cells expressed mature cholangiocyte characteristics. @*CONCLUSION@#The results of the present study demonstrate that we successfully induced the formation of hepatic progenitor cells from mf-PHs by culturing them with a combination of small molecules, including growth factors. These results offer a means of expanding nonhuman primate hepatocytes without genetic manipulation for cellular resource, preclinical applications and regenerative medicine for the liver.

Simple Maturation of Direct-Converted Hepatocytes Derived from Fibroblasts

Target cells differentiation techniques from stem cells are developed rapidly. Recently, direct conversion techniques are introduced in various categories. Unlike pluripotent stem cells, this technique enables direct differentiation into the other cell types such as neurons, cardiomyocytes, insulin-producing cells, and hepatocytes without going through the pluripotent stage. However, the function of these converted cells reserve an immature phenotype. Therefore, we modified the culture conditions of mouse direct converted hepatocytes (miHeps) to mature fetal characteristics, such as higher AFP and lower albumin (ALB) expression than primary hepatocytes. First, we generate miHeps from mouse embryonic fibroblasts (MEFs) with two transcription factors HNF4α and Foxa3. These cells indicate typical epithelial morphology and express hepatic proteins. To mature hepatic function, DMSO is treated during culture time for more than 7 days. After maturation, miHeps showed features of maturation such as exhibiting typical hepatocyte-like morphology, increased up-regulated ALB and CYP enzyme gene expression, down-regulated AFP expressions, and acquired hepatic function over time. Thus, our data provides a simple method to mature direct converted hepatocytes functionally and these cells enable them to move closer to generating functional hepatocytes.

An Unusual Case of Tubo-ovarian Abscess by Gemella morbillorum / 감염과화학요법

Gemellae is a gram positive cocci that forms part of the oropharyngeal microflora in humans and is anaerobic to aerotolerant. Unlike the other members of the same genus, G. morbillorum rarely causes human infections. Recently, we experienced a case of tubo-ovarian abscess caused by G. morbillorum which was initially suspected to be actinomycosis associated with intrauterine device. This is the first case in the world on tubo-ovarian abscess with G. morbillorum as the culprit.

An Unusual Case of Tubo-ovarian Abscess by Gemella morbillorum / 감염과화학요법

Gemellae is a gram positive cocci that forms part of the oropharyngeal microflora in humans and is anaerobic to aerotolerant. Unlike the other members of the same genus, G. morbillorum rarely causes human infections. Recently, we experienced a case of tubo-ovarian abscess caused by G. morbillorum which was initially suspected to be actinomycosis associated with intrauterine device. This is the first case in the world on tubo-ovarian abscess with G. morbillorum as the culprit.