在MAdCAM-1上滚动的L-selectin介导淋巴细胞
E L Berg1, L M McEvoy, C Berlin
1Department of Pathology, Stanford University, California 94305.
Nature
|December 16, 1993
概括
粘膜血管地址因MAdCAM-1是L-选择因的选择性连接体,支持淋巴细胞在粘膜血管上滚动. 这种相互作用对于淋巴细胞定位和粘膜组织中的免疫监测至关重要.
科学领域:
- 免疫学 免疫学 免疫学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- L-selectin是一种C型莱克,对淋巴细胞向淋巴结和皮耶斑块的流通至关重要.
- 它还调解白细胞与炎症静脉的相互作用,这是免疫细胞招募的关键过程.
- 了解淋巴细胞指导机制对于开发针对性治疗炎症和自身免疫性疾病至关重要.
研究的目的:
- 调查粘膜血管地址因MAdCAM-1是否作为L-选择因的配体.
- 描述MAdCAM-1的结合特性及其在剪切条件下的淋巴细胞粘附中的作用.
- 阐明MAdCAM-1在支持选择因和整因介导的淋巴细胞相互作用中的双重作用.
主要方法:
- 从中枢淋巴结和培养内皮瘤细胞中分离MAdCAM-1.
- 在剪切应力下使用L-选择素转移的淋巴细胞进行功能粘附测试.
- 对MAdCAM-1上的碳水化合物结构的分析,包括酸含量和N-甘氨酶耐药性.
- 对MAdCAM-1作为α4β7整合蛋白的配体的研究.
主要成果:
- 粘膜血管地址因MAdCAM-1被确定为L-选择因的可选配体.
- 来自中腔淋巴结的MAdCAM-1,但不是来自培养细胞的,支持在剪切下L-selectin介导的淋巴细胞粘附.
- 这种粘附涉及MAdCAM-1上的耐N-糖甘酶,含有酸的碳水化合物.
- 淋巴细胞在MAdCAM-1上表现出滚动行为,模仿炎症静脉中的选择依赖滚动.
- MAdCAM-1还可以作为α4β7整合蛋白的配体.
结论:
- MAdCAM-1 是一个关键的粘附分子,参与淋巴细胞向粘膜组织的指导.
- 它支持选择性介导的淋巴细胞滚动和整合性介导的粘附,促进淋巴细胞在体内被捕.
- 在粘膜部位的免疫细胞监测中,MAdCAM-1的独特特性至关重要.
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