Okada H, Woodcock-Mitchell J, Fujii S
Department of Medicine, College of Medicine, University of Vermont, Burlington 05405, USA.
Coron Artery Dis. 1996 Aug;7(8):561-7. doi: 10.1097/00019501-199608000-00001.
Pathogenetic effects of active immune cell products on the coagulation and fibrinolytic system proteins in liver and endothelial cells--primary sites of synthesis of these proteins--have not been elucidated.
We incubated highly differentiated human hepatoma cells (Hep G2) and human umbilical vein endothelial cells (HUVECs) for 24 h with recombinant human leukaemia inhibitory factor (LIF) and oncostatin M (OSM)--cytokines that are implicated in acute phase reactions during inflammation and which bind to the same cell surface receptor unit (glycoprotein gp 130). LIF was also given to mice in vivo. Contents of coagulation and fibrinolytic system proteins in cell culture supernatants and in mouse liver were determined.
LIF increased the accumulation of urokinase plasminogen activator (u-PA) in the Hep G2 cell culture supernatants determined by enzyme-linked immunosorbent assay (ELISA) (0.21 +/- 0.03 (SE) ng/ml at baseline; 0.40 +/- 0.05 ng/ml at 100 U/ml, P < 0.05; 0.57 +/- 0.06 ng/ml at 500 U/ml, P < 0.01; n = 9) without altering total protein content. OSM elicited a similar effect (0.25 +/- 0.04 ng/ml at baseline, 0.62 +/- 0.19 ng/ml at 1 ng/ml; P < 0.05, n = 6). A monoclonal antibody against gp 130 abrogated the response to both agents (n = 9). Plasminogen activator inhibitor type-1 (PAI-1) (assayed by ELISA, n = 9), the PAI-1 binding protein, vitronectin (immunoprecipitation, n = 3) and tissue factor (ELISA, n = 3) were not affected by LIF, but fibrinogen production increased up to twofold with LIF (500 U/ml; Western blot, n= 3). In HUVECs, synthesis of tissue type plasminogen activator or PAI-1 was not altered by LIF or OSM (ELISA, n = 9). In vivo, intraperitoneal recombinant murine LIF (2 mu g) increased liver concentrations of u-PA by 30% and fibrinogen by 220% in mice.
LIF and OSM produced by immune cells may modify fibrinolysis and coagulation by altering expression of u-PA and fibrinogen, thereby contributing to coagulopathy.
活性免疫细胞产物对肝脏和内皮细胞（这些蛋白质的主要合成部位）中凝血和纤维蛋白溶解系统蛋白的致病作用尚未阐明。
我们将高分化人肝癌细胞（Hep G2）和人脐静脉内皮细胞（HUVECs）与重组人白血病抑制因子（LIF）和制瘤素M（OSM）一起孵育24小时，这两种细胞因子参与炎症期间的急性期反应，并与相同的细胞表面受体单位（糖蛋白gp 130）结合。LIF也在体内给予小鼠。测定细胞培养上清液和小鼠肝脏中凝血和纤维蛋白溶解系统蛋白的含量。
通过酶联免疫吸附测定（ELISA）测定，LIF增加了Hep G2细胞培养上清液中尿激酶型纤溶酶原激活物（u-PA）的积累（基线时为0.21±0.03（SE）ng/ml；100 U/ml时为0.40±0.05 ng/ml，P<0.05；500 U/ml时为0.57±0.06 ng/ml，P<0.01；n = 9），而总蛋白含量未改变。OSM产生了类似的效果（基线时为0.25±0.04 ng/ml，1 ng/ml时为0.62±0.19 ng/ml；P<0.05，n = 6）。抗gp 130单克隆抗体消除了对这两种药物的反应（n = 9）。1型纤溶酶原激活物抑制剂（PAI-1）（通过ELISA测定，n = 9）、PAI-1结合蛋白玻连蛋白（免疫沉淀，n = 3）和组织因子（ELISA，n = 3）不受LIF影响，但LIF使纤维蛋白原产量增加了两倍（500 U/ml；蛋白质印迹法，n = 3）。在HUVECs中，LIF或OSM未改变组织型纤溶酶原激活物或PAI-1的合成（ELISA，n = 9）。在体内，腹腔注射重组鼠LIF（2μg）使小鼠肝脏中u-PA浓度增加30%，纤维蛋白原浓度增加220%。
免疫细胞产生的LIF和OSM可能通过改变u-PA和纤维蛋白原的表达来改变纤维蛋白溶解和凝血，从而导致凝血病。
