急性早幼粒细胞白血病凝血和细胞信号通路的干预

The mechanism of coagulopathy in acute promyelocytic leukemia (APL) is not clear and blocking tissue factor (TF) do not work. Phosphatidylserine (PS) is an important signal molecule on the cell aging, death and blood coagulation pathway. We first reported the localization of PS and lactadherin in cells (Science 2008;319:210-3); PS exposure is a major mechanism through which APL cells support procoagulant activity (J Thromb Haemost 2010;8:773-82); Lactadherin and phagocytosis could cooperatively reduce procoagulant and fibrinolytic activity of APL blasts (Blood. 2012; 119(10):2325-2334). For the study of APL cells, the C2 domain of lactadherin (Lact-C2) is used to tracing the localization of PS in subcellular structure of APL cells, dynamically monitoring PS in subcellular structure of APL cells after treatment with cytotoxic chemotherapy. Aims of this study is to elucidate the role that PS receptor (T-cell immunoglobin mucin (Tim-4)) plays in clearance of APL cells, investigate the rules of PS changing caused by the alteration of transmembrane protein 16F (TMEM16F) and protein disulfide isomerase (PDI), regulate PS mobile and blood coagulation from molecular and signal transduction level, and establish theoretical and technical basis for the treatment of APL clotting disorder.

急性早幼粒细胞白血病（APL）高凝血机制不清，阻断组织因子不能纠正。我们首次报道磷脂酰丝氨酸（PS）／乳粘素的细胞内外定位（Science 2008;319:210-3）、APL细胞表达PS并促进凝血（J Thromb Haemost. 2010;8:773-82）、乳粘素和吞噬协同抑制APL细胞的促凝和纤溶活性（Blood. 2012; 119（10）：2325-2334）。本项目以APL细胞为研究对象，利用我们合成的Lact-C2作为检测信号转导过程的小分子探针，活性示踪APL细胞表面及亚细胞结构上的PS，对抗肿瘤药物处理前后的APL细胞中亚细胞分布的PS进行原位、实时、动态监测；进一步研究PS受体参与的APL细胞清除途径，深入系统的研究跨膜蛋白16F和蛋白质二硫键异构酶对双向转运酶的调节，从分子和信号转导水平调控PS的移动和凝血，为治疗APL凝血紊乱奠定理论和技术基础。

急性早幼粒细胞白血病（APL）凝血病机制不清，阻断组织因子不能纠正。我们利用荧光标记技术同位示踪磷酯酰丝氨酸（PS）在药物处理前后急性早幼粒细胞白血病细胞内膜和细胞外表面的分布及动态变化。建立体外吞噬模型，检测T细胞免疫球蛋白黏液素（Tim4）在巨噬细胞和内皮细胞表面的分布，应用Tim4单克隆抗体有效抑制吞噬细胞对表达PS的NB4/APL细胞的清除。乳粘素能够协同Tim4共同参与这一吞噬过程。乳粘素竞争结合白血病细胞表面PS 从而抑制凝血通路，同时协同吞噬细胞进一步降低NB4/APL细胞凝血活性。此外，我们还完成了一些其他与本课题相关的研究，包括用乳黏素检测脓毒症，炎症性肠病及肝硬化，IgA肾病及尿毒症，结肠癌及胃癌，脑卒中及颈动脉支架等患者血细胞/内皮细胞膜表面PS及相关促凝活性的研究。我们从分子和信号转导水平调控PS的移动和凝血，为治疗APL凝血紊乱奠定理论和技术基础。