Mechanism of growth stimulatory effect of vascular endothelial cells by Bartonella henselae.

汉赛巴尔通体刺激血管内皮细胞生长的机制。

基本信息

批准号：
09670290
负责人：
ODA Hiroshi
金额：
$ 1.41万
依托单位：
Kagoshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

We studied on the mechanism of growth stimulatory effect of vascular endothelial cells by Bartonella henselae, and obtained the following results ;1. Interaction between B, henselae and human umbilical vein endothelial cells (HUVECs) : B.henselae ATCC 49882 (10^7 CFU/ml) was cocultivated with HUVECs, and the growth of HUVECs was estimated by MTT assay. The proliferation of HUVECs cocultivated with live B.henselae was enhanced in inoculated-bacterial dose dependent manner, and the stimulatory effect was specific for vascular endothelial cells. Similar growth enhancement effect was also observed in endothelial cells from rabbits or dogs.2. Active component and mechanism of growth enhancement : B.henselae killed by UV irradiation or heat treatment abolished its stimulatory activity, suggesting that the effect was exhibited by some action of live bacteria, not only by the existence of bacterial cells. To investigate the role of direct contact, live B.henselae were separated from HUVECs by membrane filter (Millicell-CM). Even under this condition, the HUVECs proliferation stimulating effect was observed. However, the morphological changes of HUVECs were not apparent compared to B.henselae infected cells. Furthermore, we isolated a nonpiliated B.henselae strain which was unable to attach to and entry into endothelial cells. The nonpiliated strain possessed the ability to stimulate the proliferation of HUVECs same as piliated strain. Our results suggested that B.henselae might produce some angiogenic factor(s) and secrete it. Further study is currently under way to purify and characterize this angiogenic factor.3. In vivo study : B.henselae was inoculated into chorioallantoic membrane of embryonated eggs, mice and guinea pigs (subcutaneous or intradermal routs), however, no angiogenic lesion was observed in the animals.

我们研究了Bartonella henselae的血管内皮细胞生长刺激作用的机理，并获得了以下结果； 1。 B，Henseleae和人脐静脉内皮细胞（HUVEC）之间的相互作用：B.henselae ATCC 49882（10^7 CFU/ml）与HUVEC共培养，并通过MTT分析估算HUVEC的生长。在接种剂量依赖性的方式中，与活芽孢杆菌共培养的HUVEC的增殖得到了增强，刺激作用是血管内皮细胞的特异性。在兔子或狗的内皮细胞中也观察到了类似的增强作用。2。活性成分和增强的机制：芽孢杆菌被紫外线照射或热处理杀死的刺激性消除了其刺激活性，这表明这种作用是通过活细菌的某些作用所表现出来的，不仅是通过细菌细胞的存在。为了研究直接接触的作用，通过膜过滤器（Millicell-CM）将活芽孢杆菌与HUVEC分离。即使在这种情况下，也观察到HUVEC的增殖刺激作用。然而，与光明乳杆菌感染的细胞相比，HUVEC的形态变化并不明显。此外，我们分离了无法附着并进入内皮细胞的非纤维化链球菌菌株。非纤维化菌株具有刺激与堆积菌株相同的HUVEC增殖的能力。我们的结果表明，B.henselae可能会产生一些血管生成因子并分泌它。目前正在进行进一步的研究以净化和表征这种血管生成因子3。体内研究：将芽孢杆菌接种到胚胎，小鼠和豚鼠的绒毛膜膜中（皮下或皮内旋转），但是，在动物中未观察到血管生成。