Ramadori G, Armbrust T
Department of Gastroenterology and Endocrinology, Georg-August-University Göttingen, Göttingen, Germany.
Eur J Gastroenterol Hepatol. 2001 Jul;13(7):777-84. doi: 10.1097/00042737-200107000-00004.
Cytokines comprise a group of small proteins released from cells in order to influence the function of other cells. By binding to highly specific cell-surface receptors, they trigger a vast array of intracellular signalling cascades. Cytokines have been described as interleukins, growth factors, interferons and chemokines. Unlike hormones, which act in a similar way, cytokines are produced by many different types of cell and act on many other types. Most of them are produced only after certain stimuli. The most intense field of cytokine activity is without doubt host defence. The liver resembles a central organ of cytokine activity due to the fact that it hosts hepatocytes, which are highly susceptible to the activity of cytokines in a variety of physiological and pathophysiological processes. Moreover, the non-parenchymal cells of the liver, in particular Kupffer cells (KCs), the resident tissue macrophages of the liver, are able to synthesize a variety of cytokines that may act systemically on any other organ of the body, or in a paracrine manner on hepatocytes and other non-parenchymal liver cells. A classic example of how cytokines act can be observed during the acute phase reaction discussed in this article. The role of cytokines in liver development, acute liver injury, liver regeneration, liver fibrosis and liver metastasis is also discussed.
细胞因子是一组从细胞中释放出来以影响其他细胞功能的小蛋白质。通过与高度特异性的细胞表面受体结合，它们触发大量的细胞内信号级联反应。细胞因子已被描述为白细胞介素、生长因子、干扰素和趋化因子。与以类似方式起作用的激素不同，细胞因子由许多不同类型的细胞产生，并作用于许多其他类型的细胞。它们中的大多数仅在特定刺激后产生。细胞因子活性最活跃的领域无疑是宿主防御。肝脏类似于细胞因子活性的中心器官，因为它含有肝细胞，肝细胞在各种生理和病理生理过程中对细胞因子的活性高度敏感。此外，肝脏的非实质细胞，特别是库普弗细胞（KCs），即肝脏的常驻组织巨噬细胞，能够合成多种细胞因子，这些细胞因子可以全身性地作用于身体的任何其他器官，或以旁分泌方式作用于肝细胞和其他肝脏非实质细胞。本文讨论的急性期反应期间可以观察到细胞因子作用的一个经典例子。还讨论了细胞因子在肝脏发育、急性肝损伤、肝再生、肝纤维化和肝转移中的作用。
