POTENTIAL OF NOVEL ANTI-INFLAMMATORY AGENTS TO SUPPRESS CHRONIC INFLAMMATION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 纤维蛋白原可诱导细胞增殖，但其部分蛋白降解片段可致内皮细胞损伤。已知整合素在纤维蛋白原的信号转导中起关键作用。纤维蛋白原伽马链有一个C-末端球状结构域(伽马链残基151-411，30kD)，几种整合素细胞黏附受体(如血小板αIIbβ3、内皮细胞αvβ3和白细胞αMβ2)与其结合。我们发现，分离的Gamma C片段及其截断突变体(Gamma C399tr，12位残基截断)在体外诱导内皮细胞凋亡，而天然纤维蛋白原或片段D不能诱导内皮细胞凋亡。Gamma C或Gamma C399tr不影响其他几种细胞类型的增殖，包括角质形成细胞和癌细胞。我们发现，在天然纤维蛋白原和蛋白降解片段D中，αvβ3的结合部位是隐蔽的，但在Gamma C和Gamma C399tr中暴露出来。这些结果表明，Gamma C和Gamma C399tr是潜在的抗血管生成药物，Gamma C和Gamma C399tr的决定簇(在纤维蛋白原和片段D中隐藏)参与了内皮细胞的凋亡，整合素可能参与了这一过程。我们还发现，在肿瘤异种移植模型中，伽玛C399tr抑制了肿瘤的生长。这些结果最近发表在[1]上。此外，我们发现伽马C399tr降低了荷瘤小鼠循环内皮细胞(CEC)的水平，循环内皮细胞(CEC)是血管生成的标志(我们的未发表结果)，我们假设这是伽马C399tr抗血管生成作用的潜在机制。近年来，人们认识到血管生成在慢性炎症中起着重要作用。我们最近发现，伽马C399tr显著抑制了实验性变态反应性脑脊髓炎(EAE)的发病，EAE是一种多发性硬化症(MS)样疾病(我们的未发表结果)。我们推测，伽马C399tr也有可能作为抗炎药，并抑制灵长类动物的血管生成和慢性炎症。 我们建议在灵长类动物炎症模型中测试伽马C399tr是否具有抗血管生成和抗炎的潜力。为此，我们将使用已建立的灵长类哮喘模型。我们预计，在该模型中，伽马C399tr将显示出抗血管生成和炎症作用，从而改善哮喘症状。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Fibrin(ogen) induces proliferative signals, but some of its proteolytic fragments induce endothelial cell injury. Integrins are known to play a critical role in signal transduction from fibrin(ogen). The fibrinogen gamma chain has a C-terminal globular domain (gamma C, residues 151-411 of gamma chain, 30 Kd) to which several integrin cell adhesion receptors (e.g., platelet alpha IIb beta 3, endothelial alpha v beta 3, and leukocyte alpha M beta 2) bind. We found that the isolated gamma C fragment and its truncation mutant (gamma C399tr, 12 residue truncation) induced apoptosis of endothelial cells in vitro, while native fibrinogen or fragment D did not. gamma C or gamma C399tr did not affect proliferation of several other cell types tested including keratinocytes and cancer cells. We found that the binding site for alpha v beta 3 is cryptic in native fibrinogen and proteolytic fragment D, but is exposed in gamma C and gamma C399tr. These results suggest that gamma C and gamma C399tr are potential anti-angiogenic agents, that determinants in gamma C and gamma C399tr (which are cryptic in fibrinogen and fragment D) are involved in endothelial cell apoptosis, and that integrins are potentially involved in this process. Also we showed that gamma C399tr suppressed tumor growth in tumor xenograft models. These results were recently published [1]. Furthermore we found that gamma C399tr reduced the level of circulating endothelial cells (CEC), a marker of angiogenesis, in tumor-bearing mice (our unpublished results) and we hypothesize that this is a potential mechanism of anti-angiogenic action by gamma C399tr. It has been recently recognized that angiogenesis plays a role in chronic inflammation. We recently found that gamma C399tr markedly suppressed the onset of experimental allergic encephalomyelitis (EAE), a multiple sclerosis (MS)-like disease in mice (our unpublished results). We hypothesize that gamma C399tr may have potential as an anti-inflammatory agent as well, and suppress angiogenesis and chronic inflammation in primate. We propose to test whether gamma C399tr may have potential as anti-angiogenic and anti-inflammatory agent in primate inflammation models. We will use the well-established primate asthma model for this purpose. We expect that gamma C399tr will show anti-angiogenic and inflammatory effects and thus improve asthma symptoms in this model.