Edwards R L, Perla D
Blood. 1984 Sep;64(3):707-14.
Human monocytes generate the procoagulant tissue factor (MTF) following exposure to a variety of immune stimuli in vitro. The generation of MTF is modified by T cells, lymphokines, and immunoregulatory lipoproteins, and recent studies have shown that MTF can be activated in an immune-specific manner following exposure to antigen. We have examined the role of serum factors in the regulation of MTF generation. Low concentrations (less than 1%) of heat-inactivated normal human serum greatly enhanced MTF generation in cultures of normal peripheral blood mononuclear cells. The stimulatory effect was observed in cultures of both unstimulated cells and cells exposed to bacterial lipopolysaccharide. Stimulation was not observed at high serum concentrations (greater than 10%) and could not be explained by endotoxin contamination or activation of the assay system. Stimulatory activity was present in plasma and BaSO4-adsorbed plasma as well as autologous and allogeneic serum, was not abolished by removal of serum lipoproteins, and did not require the presence of T cells for its expression. Sera from 28 different normal volunteers were screened for stimulatory activity and demonstrated a wide variation in potency. These results suggest that a potent factor is present in sera that enhances the expression of MTF activity in vitro. This factor is distinct from previously described lipoprotein regulators and may play a role in the initiation of coagulation in both normal hemostasis and pathologic states.
人单核细胞在体外暴露于多种免疫刺激后会产生促凝血组织因子（MTF）。MTF的产生会受到T细胞、淋巴因子和免疫调节脂蛋白的影响，最近的研究表明，MTF在暴露于抗原后可通过免疫特异性方式被激活。我们研究了血清因子在MTF产生调节中的作用。低浓度（低于1%）热灭活的正常人血清可显著增强正常外周血单个核细胞培养物中MTF的产生。在未刺激细胞和暴露于细菌脂多糖的细胞培养物中均观察到这种刺激作用。在高血清浓度（大于10%）时未观察到刺激作用，且这不能用内毒素污染或检测系统的激活来解释。刺激活性存在于血浆、硫酸钡吸附血浆以及自体和异体血清中，去除血清脂蛋白并不能消除这种活性，且其表达不需要T细胞的存在。对28名不同正常志愿者的血清进行了刺激活性筛选，结果显示其效力存在很大差异。这些结果表明，血清中存在一种强效因子，可在体外增强MTF活性的表达。该因子不同于先前描述的脂蛋白调节因子，可能在正常止血和病理状态下的凝血启动过程中发挥作用。
