Neutrophil transit times through pulmonary capillaries: The effects of capillary geometry and fMLP-stimulation
Neutrophil transit times through pulmonary capillaries: The effects of capillary geometry and fMLP-stimulation
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DOI：
10.1016/s0006-3495(02)73955-6
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发表时间：
2002-10-01
影响因子：
3.4
通讯作者：
Kamm, RD
中科院分区：
文献类型：
--
作者：
Bathe, M;Shirai, A;Kamm, RD
当中性粒细胞通过肺微循环时，其变形影响其通过时间、其与内皮表面接触和相互作用的趋势以及潜在地影响其活化程度。在这里，我们将细胞建模为由恒定表面张力约束的粘弹性麦克斯韦材料，并模拟压痕实验以量化（N-甲酰基-L-甲硫氨酰基-L-亮氨酰基-L-苯丙氨酸（fMLP）刺激对其机械性质（弹性剪切模量和粘度）的影响。然后，我们模拟中性粒细胞通过单个肺毛细血管段，以确定毛细血管几何形状和fMLP刺激对通过时间的相对影响。压痕结果表明，中性粒细胞粘度和剪切模量分别比未刺激的细胞值（测定为30.8 Pa.s和185 Pa）增加3.4倍（对于10（-9）M fMLP）和7.3倍（对于10（-6）M fMLP）。毛细管流动的结果表明，毛细管入口曲率半径有显着的影响细胞通过时间，除了最小毛细管半径和中性粒细胞刺激水平。毛细血管几何形状和fMLP对中性粒细胞通过时间的相对影响作为一个简单的无量纲表达式，其生理意义进行了讨论。
The deformations of neutrophils as they pass through the pulmonary microcirculation affect their transit time, their tendency to contact and interact with the endothelial surface, and potentially their degree of activation. Here we model the cell as a viscoelastic Maxwell material bounded by constant surface tension and simulate indentation experiments to quantify the effects of (N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP)-stimulation on its mechanical properties (elastic shear modulus and viscosity). We then simulate neutrophil transit through individual pulmonary capillary segments to determine the relative effects of capillary geometry and fMLP-stimulation on transit time. Indentation results indicate that neutrophil viscosity and shear modulus increase by factors of 3.4, for 10(-9) M fMLP, and 7.3, for 10(-6) M fMLP, over nonstimulated cell values, determined to be 30.8 Pa.s and 185 Pa, respectively. Capillary flow results indicate that capillary entrance radius of curvature has a significant effect on cell transit time, in addition to minimum capillary radius and neutrophil stimulation level. The relative effects of capillary geometry and fMLP on neutrophil transit time are presented as a simple dimensionless expression and their physiological significance is discussed.