白细胞以生理流速在选择蛋白上滚动:与整合素的粘附有区别,也是通过整合素粘附的先决条件
1Center for Blood Research, Boston, Massachusetts 02115.
Cell
|May 31, 1991
概括
白细胞在选择蛋白上滚动是炎症的关键早期步骤. 这项研究表明,选择介导的滚动对于在流动下中性粒细胞中基于整合素的粘附强化是必要的.
科学领域:
- 细胞生物学 细胞生物学
- 免疫学 免疫学 免疫学
- 生物物理学的生物物理.
背景情况:
- 炎症涉及白细胞在内皮细胞上滚动,这是由CD62.2等选择因介导的早期事件.
- 中性粒细胞对内皮细胞的粘附对于免疫反应至关重要,但需要特定的分子相互作用.
- 在生理流动条件下理解这些相互作用对于理解炎症过程至关重要.
研究的目的:
- 为了研究选择介导滚动在流动下中性粒细胞粘附中的作用.
- 确定整合素 (LFA-1,Mac-1) 在选择素和ICAM-1的存在下对中性粒细胞粘附的贡献.
- 为了阐明导致在炎症期间稳定中性粒细胞粘附的事件序列.
主要方法:
- 在体外实验中,使用人工脂质双层与纯化的选择蛋白CD62和ICAM-1重复组合.
- 在受控的流量条件下研究中性粒细胞滚动和粘附,模仿毛囊后静脉.
- 评估与人工表面相互作用的中性粒细胞的粘附强度和剪切阻力,有或没有化学吸引剂刺激.
主要成果:
- 在生理剪切应力下,中性粒细胞在含有CD62的脂质二层上滚动.
- 在生理剪切时,因特林介导的粘附于ICAM-1是最小的,但在静态化激活中性粒细胞时显著增加.
- 化学吸引剂诱导的整合素激活导致 CD62 和 ICAM-1 含有双层的滚动中性粒细胞停止,表明粘附强化.
结论:
- 选择蛋白依赖的白细胞滚动是随后在中性粒细胞中因整蛋白介导的粘附强化的先决条件.
- 从滚动到稳定的粘附的过渡是由激素吸引剂信号调节的,这些信号会激活整合素.
- 这项研究提供了体外证据,证明了在炎症期间控制中性粒细胞招募的序列分子事件.
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