Brody J P, Han Y, Austin R H, Bitensky M
Department of Physics, Princeton University, New Jersey 08544, USA.
Biophys J. 1995 Jun;68(6):2224-32. doi: 10.1016/S0006-3495(95)80443-1.
We introduce the use of microfabrication techniques to construct on a silicon wafer a synthetic capillary bed with 2.5- to 4-micron (mu)-wide channels. Establishment of a fluid pressure gradient allowed us to observe simultaneously using optical microscopy hundreds of cells flowing through the bed at physiological speeds. We find a large distribution of mobilities among red cells flowing through the structure; smaller channels provide a greater impedance to flow than larger ones, indicating that kinetic drag variations provide the origin of the distribution. The mobility of a particular cell is not correlated with the cell diameter but appears to be inversely correlated with intracellular calcium concentration of the cell, as determined by fluorescence of the calcium-binding dye fluo-3 AM. Also, we are able to use the parallel processing nature of our arrays to observe isolated events where the rigidity of the red cell seems to change suddenly over several orders of magnitude as it blocks a channel in the array.
我们介绍了利用微加工技术在硅片上构建具有2.5至4微米宽通道的合成毛细血管床。建立流体压力梯度使我们能够使用光学显微镜同时观察数百个细胞以生理速度流过该床。我们发现流经该结构的红细胞之间迁移率分布范围很大；较小的通道比较大的通道对流动的阻碍更大，这表明动力学阻力变化是该分布的根源。特定细胞的迁移率与细胞直径无关，但似乎与细胞内钙浓度呈负相关，这是通过钙结合染料fluo-3 AM的荧光测定的。此外，我们能够利用阵列的并行处理特性来观察孤立事件，即红细胞在阻塞阵列中的通道时，其刚性似乎会在几个数量级上突然变化。
