Carloni V, Romanelli R G, Pinzani M, Laffi G, Gentilini P
Istituto di Medicina Interna-Centro Interuniversitario di Fisiopatologia Epatica, Universita di Firenze, Italy.
Gastroenterology. 1996 Apr;110(4):1127-36. doi: 10.1053/gast.1996.v110.pm8613002.
BACKGROUND & AIMS: Human hepatic stellate cells (HSCs), liver-specific pericytes, are currently considered major producers of extracellular matrix (ECM) components and key elements in the development of liver fibrogenesis. However, little is known about the possible functional interactions between HSCs and the various ECM components. Therefore, the present study was designed to evaluate the expression of integrins, the major family of extracellular matrix receptors.
Integrin expression was evaluated by immunoprecipitation and confirmed by immunocytochemistry and flow cytometry.
Human HSCs were shown to express alpha1beta1, alpha2beta1, alpha(v)beta1. Adhesion to type IV collagen, type I collagen, fibronectin, and laminin 1 was inhibited by anti-beta1 antibody identifying beta1-containing integrins as possible receptors for these components. In addition, we showed that HSCs express alpha6beta4, a heterodimer known to mediate adhesion of epithelial cells to laminin and not previously characterized in mesenchymal cells. Adhesion to laminin 1 was not inhibited by antibodies specific for alpha6 or beta4, thus establishing that laminin 1 is not a ligand for alpha6beta4 in this cell type.
These findings represent the first description of integrin receptors in HSC and provide an attempt to cover the gap of information in the field of HSC-ECM interactions.
人肝星状细胞（HSCs），即肝脏特异性周细胞，目前被认为是细胞外基质（ECM）成分的主要产生者以及肝纤维化发生发展的关键因素。然而，关于HSCs与各种ECM成分之间可能存在的功能相互作用，我们了解甚少。因此，本研究旨在评估整合素（细胞外基质受体的主要家族）的表达情况。
通过免疫沉淀评估整合素表达，并通过免疫细胞化学和流式细胞术进行确认。
研究表明，人HSCs表达α1β1、α2β1、α(v)β1。识别含β1整合素的抗β1抗体可抑制HSCs与IV型胶原、I型胶原、纤连蛋白和层粘连蛋白1的黏附，这表明含β1整合素可能是这些成分的受体。此外，我们发现HSCs表达α6β4，这是一种已知可介导上皮细胞与层粘连蛋白黏附的异二聚体，此前在间充质细胞中未被鉴定。α6或β4特异性抗体不能抑制HSCs与层粘连蛋白1的黏附，因此确定层粘连蛋白1不是该细胞类型中α6β4的配体。
这些发现首次描述了HSCs中的整合素受体，并试图填补HSC-ECM相互作用领域的信息空白。
