De Minicis Samuele, Seki Ekihiro, Uchinami Hiroshi, Kluwe Johannes, Zhang Yonghui, Brenner David A, Schwabe Robert F
Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, New York 10032, USA.
Gastroenterology. 2007 May;132(5):1937-46. doi: 10.1053/j.gastro.2007.02.033. Epub 2007 Feb 21.
BACKGROUND & AIMS: Following hepatic injury, hepatic stellate cells (HSCs) transdifferentiate to become extracellular matrix-producing myofibroblasts and to promote hepatic fibrogenesis. In this study, we determine gene expression changes in 3 different models of HSC activation and investigate whether HSC culture activation reproduces gene expression changes of HSC in vivo activation.
HSCs were isolated by density centrifugation and magnetic antibody cell sorting from normal mice, CCl(4)-treated mice, and mice that underwent bile duct ligation (BDL). Gene expression was analyzed by microarray and confirmed by polymerase chain reaction and Western blot analysis.
Two thousand seventy-three probe sets were differentially expressed in at least 1 of 3 models of HSC activation, including novel genes that encode proinflammatory and antiapoptotic mediators; transcription factors; cell surface receptors; and cytoskeleton components such as CXCL14, survivin, septin 4, osteopontin, PRX1, LMCD1, GPR91, leiomodin, and anillin. BDL- and CCl(4)-activated HSCs showed highly correlated gene expression patterns, whereas culture activation only partially reproduced the gene expression changes observed during BDL- and CCl(4)-induced activation. Coculture with Kupffer cells or lipopolysaccharide treatment during culture activation shifted the expression of most examined genes toward the pattern observed during in vivo activation, suggesting a role for these factors in the microenvironment that drives HSC activation.
The almost identical HSC gene expression patterns after BDL or CCl(4) treatment indicate that HSCs exert similar functions in different types of liver injury. Because culture activation does not properly regulate gene expression in HSCs, in vivo activation should be considered the gold standard for the study of HSC biology.
肝损伤后，肝星状细胞（HSCs）转分化为产生细胞外基质的肌成纤维细胞，促进肝纤维化形成。在本研究中，我们确定了3种不同的肝星状细胞激活模型中的基因表达变化，并研究肝星状细胞培养激活是否能重现其体内激活时的基因表达变化。
通过密度离心和磁珠抗体细胞分选技术，从正常小鼠、四氯化碳（CCl₄）处理的小鼠和胆管结扎（BDL）小鼠中分离肝星状细胞。通过微阵列分析基因表达，并通过聚合酶链反应和蛋白质印迹分析进行验证。
在3种肝星状细胞激活模型中的至少1种中，有2073个探针集存在差异表达，包括编码促炎和抗凋亡介质、转录因子、细胞表面受体以及细胞骨架成分（如CXCL14、生存素、septin 4、骨桥蛋白、PRX1、LMCD1、GPR91、平滑肌动蛋白和网蛋白）的新基因。BDL和CCl₄激活的肝星状细胞显示出高度相关的基因表达模式，而培养激活仅部分重现了BDL和CCl₄诱导激活过程中观察到的基因表达变化。在培养激活过程中与库普弗细胞共培养或用脂多糖处理，可使大多数检测基因的表达向体内激活时观察到的模式转变，表明这些因素在驱动肝星状细胞激活的微环境中起作用。
BDL或CCl₄处理后肝星状细胞几乎相同的基因表达模式表明，肝星状细胞在不同类型的肝损伤中发挥相似的功能。由于培养激活不能正确调节肝星状细胞中的基因表达，体内激活应被视为肝星状细胞生物学研究的金标准。
