概括
纤维细胞结合并内化组织等离子体激活剂 (tPA). 纤维细胞的这种酶封存涉及表面受体,导致tPA降解,并且与蛋白质素介导的结合不同.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生化学
- 酶学 是一种酶学.
背景情况:
- 组织等离子体激活剂 (tPA) 对于纤维素分解至关重要.
- 了解tPA与细胞的相互作用对于其治疗应用至关重要.
- 纤维细胞是参与组织重塑和矩阵动态的常见细胞.
研究的目的:
- 调查纤维细胞与组织等离子体激活剂 (tPA) 相互作用和内化机制.
- 描述结合动力学和参与纤维细胞tPA封存的细胞组件.
- 为了区分这种相互作用与其他已知的tPA结合现象.
主要方法:
- 用含有tPA的介质化活体和固定在乙醇中的纤维细胞.
- 对tPA结合和封存的动态分析.
- 结合tPA的酶活性测定.
- 电泳分析以确定结合元件.
- 研究肝素和血栓素对结合的作用.
主要成果:
- 纤维细胞有效地结合并从介质中去除tPA.
- 结合固定细胞表现出平衡动力学,最大吸收量为2.4个单位/106个细胞.
- 结合的tPA保留了酶活性,激活了等离子体,并引起了类溶解.
- 电泳揭示了tPA与40-50kDa的纤维细胞组成部分共振连接.
- 通过活细胞的隔离遵循非和的第一阶动力学 (k=0.465/hr).
- 结合独立于肝素和血栓,结合分子不会释放到介质中.
结论:
- 纤维细胞具有活性组织等离子体激活剂 (tPA) 的表面受体.
- 结合后,tPA被内部化,随后被纤维细胞降解.
- 这种纤维细胞介导的tPA结合机制与蛋白质素介导的结合有所区别.
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