Arai Shunto
Department of Applied Physics, Graduate School of Engineering, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan.
Int J Mol Sci. 2015 Dec 7;16(12):29148-60. doi: 10.3390/ijms161226149.
Blood vessels are essential organs that are involved in the supply of nutrients and oxygen and play an important role in regulating the body's internal environment, including pH, body temperature, and water homeostasis. Many studies have examined the formation of networks of endothelial cells. The results of these studies have revealed that vascular endothelial growth factor (VEGF) affects the interactions of these cells and modulates the network structure. Though almost all previous simulation studies have assumed that the chemoattractant VEGF is present before network formation, vascular endothelial cells secrete VEGF only after the cells bind to the substrate. This suggests VEGF is not essential for vasculogenesis especially at the early stage. Using a simple experiment, we find chain-like structures which last quite longer than it is expected, unless the energetically stable cluster should be compact. Using a purely physical model and simulation, we find that the hydrodynamic interaction retard the compaction of clusters and that the chains are stabilized through the effects of charge. The charge at the surface of the cells affect the interparticle potential, and the resulting repulsive forces prevent the chains from folding. The ions surrounding the cells may also be involved in this process.
血管是重要的器官，参与营养物质和氧气的供应，并在调节身体内部环境（包括pH值、体温和水平衡）中发挥重要作用。许多研究已经考察了内皮细胞网络的形成。这些研究结果表明，血管内皮生长因子（VEGF）影响这些细胞的相互作用并调节网络结构。尽管几乎所有先前的模拟研究都假定趋化因子VEGF在网络形成之前就已存在，但血管内皮细胞仅在细胞与底物结合后才分泌VEGF。这表明VEGF对于血管生成并非必不可少，尤其是在早期阶段。通过一个简单的实验，我们发现链状结构持续的时间比预期长得多，除非能量稳定的聚集体应该是紧密的。使用一个纯粹的物理模型和模拟，我们发现流体动力相互作用会阻碍聚集体的压实，并且链通过电荷效应得以稳定。细胞表面的电荷影响粒子间的势能，由此产生的排斥力阻止链折叠。细胞周围的离子也可能参与这一过程。
