Role of T-cell derived prothrombin in septicemia

丝氨酸蛋白酶凝血酶参与止血以外的许多生理功能，包括血管生成、胚胎发生、肿瘤发生和炎症。凝血酶原的血清水平来源于肝脏中的蛋白质合成，但凝血酶原（F2）基因在各种其他组织中的表达已被证明发生在胚胎发生期间。虽然已经获得了相当多的见解，凝血酶如何发挥其重要作用，在各种病理，很少有人知道的（病理）生理功能的肝外凝血酶原表达。通过产生骨髓嵌合体动物，其中凝血酶原在骨髓隔室中被选择性地消融，我们最近观察到骨髓来源的凝血酶原在败血症中的关键功能。在骨髓来源的细胞中特异性地消融凝血酶原表达导致败血症中较高的存活率，尽管凝血酶原的血清水平未改变。为了鉴定在骨髓隔室中表达凝血酶原的细胞类型，我们采用磁性（MACS）和荧光激活细胞分选（FACS），然后基于从新设计的转基因小鼠模型（称为“D-Insight”）获得的纯化细胞进行光度测定，其中内源性凝血酶原表达被荧光素酶报告基因标记。通过MACS和FACS分离不同的骨髓来源的细胞群，然后进行光度测定，我们鉴定了表达凝血酶原的抗原经历的CD 4和CD 8阳性T细胞。我们现在想解释骨髓来源的凝血酶原表达在败血症调节中的神秘功能作用。为此，我们将利用组织特异性凝血酶原基因敲除小鼠，并将其与体内和体外功能研究、组学和药理学方法结合联合收割机，以解开T细胞来源的凝血酶原在败血症中的作用。阐明凝血成分在止血功能之外的非规范功能是阐明其对非常常见和最具破坏性疾病的病理生理学的贡献的核心。这也可能有助于新的途径，以确定合理的目标，以打击败血症，一个最新的致命条件，为一个显着比例的受影响的患者在地球仪。

The serine protease thrombin is involved in a number of physiological functions beyond hemostasis including angiogenesis, embryogenesis, tumorigenesis and inflammation. Serum levels of prothrombin derive from protein synthesis in the liver, yet expression of the prothrombin (F2) gene in a variety of other tissues has been demonstrated to occur during embryogenesis. While considerable insights have been obtained on how thrombin exerts its crucial function in various pathologies, little is known about the (patho)physiological functions of extrahepatic prothrombin expression. By generating bone marrow chimeric animals in which prothrombin is selectively ablated in the bone marrow compartment, we recently observed a critical function of bone marrow-derived prothrombin in septicemia. Ablation of prothrombin expression specifically in bone marrow-derived cells led to a higher survival rate in septicemia despite unaltered serum levels of prothrombin. To identify cell type(s) expressing prothrombin in the bone marrow compartment, we employed magnetic- (MACS) and fluorescence-activated cell sorting (FACS) followed by luminometry based on purified cells obtained from a newly designed transgenic mouse model (termed ‘D-Insight’) in which endogenous prothrombin expression is tagged by luciferase reporters. Isolating different bone marrow-derived cell populations by MACS and FACS followed by luminometry, we identified antigen-experienced CD4- and CD8- positive T-cells to express prothrombin. We now want to decipher the enigmatic functional role of bone marrow-derived prothrombin expression in the modulation of septicemia. To this end, we will make use of tissue-specific prothrombin knock-out mice and combine this with functional studies in vivo and in vitro, omics and pharmacological approaches to disentangle the role of T-cell derived prothrombin in septicemia. Illuminating non-canonical functions of coagulation components beyond their hemostatic functions is central to elucidate their contribution to the pathophysiologies of very common and most devastating disorders. This may also aid novel avenues to identify rationalized targets for combatting septicemia, an up-to-date fatal condition for a significant proportion of affected patients around the globe.