单个细胞级别的粘附力测定（二）
FluidFM 测定细胞粘附力的应用
随着时间推移，越来越多的学者开始使用FluidFM 技术进行测定细胞粘附力。以下就近五年的具有代表性的应用进行总结。
Cohen 等使用FluidFM 技术对MCF7-MCF10A、MCF7-HS5 的细胞粘附力进行了测定，并与以往的文献进行对比，发现其数据与Hossein 等测定的结果相符。如下图所示：
使用FluidFM 技术对MCF7-MCF10A、MCF7-HS5 细胞粘附力进行测定 a. 使用FluidFM 测定细胞粘附力全过程；b. MCF7-HS5 的细胞粘附力测试结果；c. MCF7-MCF10A 的细胞粘附力测试结果。
Jaatinen 等通过使用FluidFM 技术研究外加电流对C2C12 小鼠成肌细胞粘附力的影响中发现随着外周电流的增加，细胞形态发生改变，与基质接触面积降低。当电流剂量高过11As/m2后细胞形态
FluidFM 测定C2C12 细胞粘附力 a.使用FluidFM 测定粘附力显微镜图；b.施加12.3As/m2电流和空白对照组的粘附力谱线；c.粘附力与电流之间的量效关系图。
Sankaran 等使用FluidFM 来研究共价和非共价的表面整合素受体对细胞粘附力的影响。通过测定发现两者均可有效增加细胞的粘附能力，并且效果近似。
使用FluidFM 技术测定共价键与非共价键之间的整合素受体RGD 之间的区别 a. FluidFM 测定粘附力的示意图； b. 细胞粘附力测定前后显微镜示意图； c.测定粘附力时候的力学曲线图；d. 最
Sancho 等通过FluidFM 技术使用了一种非常有趣的测量方法来测量MSX1 过表达对细胞骨架的影响，他们首先将10μm 的小胶球固定在探针上，之后使用探针去压细胞直到探针压力达到2 nN，通过压痕曲线来分析细胞骨架变化。通过对比发现过量表达MSX1 细胞的硬度显著比普通细胞高。如下图所示：
使用FluidFM 技术测定HUAEC 中MSX1
过表达对细胞骨架的影响。a. HUAEC
细胞的免疫荧光染色phalloidin（上）、vimentin（下）（绿色）Hoechst（蓝色）；b. HUAEC
细胞的免疫荧光染色phalloidin（红色）、vinculin（绿色）TOPRO-3（蓝色）；c. 每个克隆中vinculin 阳性面积；d.
使用FluidFM 技术压细胞的示意图；e. 吸取10μm 珠子；f. 空白细胞下压时的力学谱线；g. MSX
过表达细胞下压时的力学谱线，更深的凹陷和平滑的斜率表示较低的刚度； h.用胶体压痕法测定细胞刚度的测量结果。
总结
细胞粘附力测定在细胞生命科学研究中起着至关重要的作用，然而传统手段中有着各种各样的局限性，这主要原因是缺乏一种有效能够抓取细胞并进行力学测定的手段。现如今FluidFM
技术在细胞粘附力测定中的使用，使得研究者们有了一种能够有效、低损的方式抓取细胞，并配合着原子力显微镜的精确测量的特性，从而能够真正意义上的做到精准、无损、快速的测量单细胞粘附力，帮助研究者寻找细胞粘附力与细胞生命发展、肿瘤细胞转移之间的关系。
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