Henn V, Slupsky J R, Gräfe M, Anagnostopoulos I, Förster R, Müller-Berghaus G, Kroczek R A
Molecular Immunology, Robert Koch-Institute, Berlin, Germany.
Nature. 1998 Feb 5;391(6667):591-4. doi: 10.1038/35393.
CD40 ligand (CD40L, CD154), a transmembrane protein structurally related to the cytokine TNF-alpha, was originally identified on stimulated CD4+ T cells, and later on stimulated mast cells and basophils. Interaction of CD40L on T cells with CD40 on B cells is of paramount importance for the development and function of the humoral immune system. CD40 is not only constitutively present on B cells, but it is also found on monocytes, macrophages and endothelial cells, suggesting that CD40L has a broader function in vivo. We now report that platelets express CD40L within seconds of activation in vitro and in the process of thrombus formation in vivo. Like TNF-alpha and interleukin-1, CD40L on platelets induces endothelial cells to secrete chemokines and to express adhesion molecules, thereby generating signals for the recruitment and extravasation of leukocytes at the site of injury. Our results indicate that platelets are not only involved in haemostasis but that they also directly initiate an inflammatory response of the vessel wall.
CD40配体（CD40L，CD154）是一种结构上与细胞因子肿瘤坏死因子-α相关的跨膜蛋白，最初在活化的CD4 + T细胞上被鉴定出来，后来在活化的肥大细胞和嗜碱性粒细胞上也被发现。T细胞上的CD40L与B细胞上的CD40相互作用对于体液免疫系统的发育和功能至关重要。CD40不仅组成性地存在于B细胞上，还存在于单核细胞、巨噬细胞和内皮细胞上，这表明CD40L在体内具有更广泛的功能。我们现在报告，血小板在体外活化后数秒内以及在体内血栓形成过程中表达CD40L。与肿瘤坏死因子-α和白细胞介素-1一样，血小板上的CD40L诱导内皮细胞分泌趋化因子并表达黏附分子，从而产生损伤部位白细胞募集和外渗的信号。我们的结果表明，血小板不仅参与止血，还直接引发血管壁的炎症反应。
