武汉云克隆科技股份有限公司

Abstract:

BACKGROUND:

When the prekallikrein-high molecular weight kininogen complex (PK-HK) is bound to endothelial cells, prekallikrein is stoichiometrically converted to kallikrein due to release of heat shock protein-90 (Hsp90).

RATIONALE:

Since attacks of hereditary angioedema can be related to infection or to estrogen we questioned whether estrogen or cytokine stimulation of endothelial cells could augment release of Hsp90 and prekallikrein activation. We also tested release of profibrinolytic enzymes, urokinase (UK) and tissue plasminogen activator (TPA).

METHODS: 

Cells were stimulated with agonists and Hsp90, UK, and TPA were measured in the culture supernatants by ELISA. Activation of the PK-HK complex was measured employing pro-phe-arg-p-nitroanilide reflecting kallikrein formation.

RESULTS: 

Hsp90 release was stimulated with optimal doses of estradiol, IL-1, and TNFa (10ng/ml) from 15 min to 120 min. TPA release was not augmented by any of the agonists tested but UK was released by IL-1, TNFa and thrombin (positive control) but not estrogen. Augmented activation of PK-HK was seen with each agonist that releases Hsp90. Addition of 0.1molar factor XII relative to PK-HK leads to rapid formation of kallikrein; factor XII alone does not autoactivate.

CONCLUSIONS: 

Interleukin-1, TNFa, and estrogen stimulate release of Hsp90 and augment activation of the PK-HK complex. IL-1 and TNFa stimulate release of urokinase which can augment fibrinolysis.

CLINICAL IMPLICATION:

Attacks of angioedema in patients with HAE may be initiated by use of estrogen or infection.Cytokine or estrogen stimulation of endothelial cells and activation of the PK-HK complex may contribute to this process.

摘要：

背景：

当激肽释放酶-高分子激肽原复合物(pk-hk)与内皮细胞结合时，热休克蛋白-90(Hsp90)释放，前激肽释放酶转化为激肽释放酶。

原理：

由于遗传性血管水肿的发作可能与感染或雌激素有关，我们猜想雌激素或细胞因子对内皮细胞的刺激可能会促进Hsp90的释放和前激肽释放酶的活化。此外我们也检测了纤溶酶原、尿激酶(UK)和组织纤溶酶原激活物(TPA)的释放。

方法：

激动剂刺激细胞，采用ELISA法测定培养上清液中HSP 90、UK和TPA的含量。对硝基苯胺反射激肽释放酶的形成用于检测PK-HK复合物的活性。

结果：

最佳剂量的雌二醇、IL-1和TNFa(10ng/ml)刺激HSP90释放15分钟至120分钟。任何一种激动剂对TPA释放不起作用，但IL-1、TNFa和凝血酶(阳性对照)对UK释放起作用，而雌激素无作用。每一种释放Hsp 90的激动剂都能增强PK-HK的活性。在pk-hk的基础上加入0.1mol因子XII，可使激肽释放酶迅速形成；因子XII本身并不是自激活的。

结论：

IL-1，TNFa和雌激素刺激HSP 90的释放和PK-HK复合体的活化。IL-1和TNFa刺激尿激酶的释放，从而增加纤维蛋白溶解。

临床意义：

HAE患者血管水肿的发病可能是由雌激素或感染引起的。细胞因子或雌激素刺激内皮细胞和激活PK-HK复合物可能参与了这一过程。