氨酸抑制了对白细胞整体蛋白Mac-1 (CD11b/CD18) 的连接
K Peter1, M Schwarz, C Conradt
1Department of Internal Medicine III, University of Heidelberg, Germany. peter@mm31.ukl.uni-freiburg.de
Circulation
|October 6, 1999
概括
氨酸与整合素Mac-1结合,抑制其功能和白细胞的粘附. 这一发现解释了氨酸除了抗凝固之外的临床益处,影响炎症和细胞增殖.
科学领域:
- 免疫学 免疫学 免疫学
- 血液学 血液学 血液学
- 药理学 药理学是指药理学的学科.
背景情况:
- 氨酸表现出除了抗凝固之外的临床益处.
- 白细胞对肝素的粘附是由整体蛋白Mac-1 (CD11b/CD18) 介导的.
- 抑制Mac-1可以解释肝素的有益作用.
研究的目的:
- 为了研究是否可溶性氨酸在体外和体内调节Mac-1功能.
- 探索肝素在白细胞粘附和整蛋白活性中的作用.
主要方法:
- 流细胞计测试以证明肝素在刺激的白细胞上与Mac-1结合.
- 测试以评估抑制Mac-1连接物结合 (纤维原,X因子,iC3b).
- 在ICAM-1上使用单细胞细胞系和初级白细胞进行细胞粘附测定.
主要成果:
- 未分离的肝素在刺激的单细胞和颗粒细胞上与Mac-1结合.
- 氨酸抑制纤维素素,X因子和IC3b与Mac-1的结合.
- 肝素会损害白细胞对ICAM-1的粘附,这与抑制Mac-1抗体相当.
- 低分子量肝素也抑制了纤维素原与Mac-1的结合.
- 在体内,肝素抑制纤维素-Mac-1结合与aPTT延长相关.
结论:
- 氨酸与Mac-1结合,这是一个新的药理学相关性质.
- 这种相互作用抑制了Mac-1连接体的结合,调节凝血和炎症.
- 肝素对Mac-1的影响可能有助于其广泛的临床益处.
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