标题： 共轭脉动上皮中的集体同步性 显示英文标题

标题： Collective synchrony in confluent, pulsatile epithelia

摘要： 集体细胞迁移位于发育生物学和非平衡物理学的交叉点，其中主动过程产生具有生物学意义的涌现模式。 在这里，我们研究上皮单层中的膨胀模式——扩张和收缩的循环，并表明速度场的散度表现出稳健的大尺度时间振荡。 这些振荡模式类似于可激发介质及其生物类似物，从主动搏动细胞的耦合动力学中自发出现。 我们发现这些振荡的时间持续性随着细胞密度的变化呈非单调变化：同步性最初随密度增加，在中间密度时达到最大值，随后在较高密度时消失。 这一趋势与细胞间相互作用的空间相关长度以及系统中拓扑缺陷的密度变化相呼应，表明它们有共同的物理起源。 我们开发了一个连续体模型，其中复数形式的Ginzburg-Landau型场控制振荡的幅度和相位，并与局部细胞密度耦合。 模拟再现了观察到的行为，揭示了局部密度适应相位模式，从而在临界密度之前增强时间相干性，并随着细胞密度变化表现出拓扑缺陷密度的变化。 将我们的分析扩展到侵袭性逐渐增强的乳腺癌细胞系，我们发现恶性细胞表现出更长的相位持续性和更少的拓扑缺陷，这表明时间相干性与转移潜力之间存在机制上的联系。 综上所述，这些结果突显了密度依赖的同步动力学作为活性上皮物质中一种基本且可量化的集体行为模式的作用，对形态发生、癌症进展和组织诊断具有重要意义。 显示英文摘要

摘要： Collective cell migration lies at the intersection of developmental biology and non-equilibrium physics, where active processes give rise to emergent patterns that are biologically relevant. Here, we investigate dilatational modes--cycles of expansion and contraction--in epithelial monolayers, and show that the divergence of the velocity field exhibits robust, large-scale temporal oscillations. These oscillatory patterns, reminiscent of excitable media and their biological analogs, emerge spontaneously from the coupled dynamics of actively pulsing cells. We find that the temporal persistence of these oscillations varies non-monotonically with cell density: synchrony initially increases with density, reaches a maximum at intermediate densities and is lost at higher values. This trend mirrors changes in the spatial correlation length of cell-cell interactions, and the density of topological defects in the system, suggesting a shared physical origin. We develop a continuum model in which a complex-valued Ginzburg-Landau-type field that governs the amplitude and phase of oscillations is coupled to local cell density. Simulations reproduce the observed behavior, revealing that local density adapts to phase patterns, reinforcing temporal coherence up to a critical density, and variations in the density of topological defects as a function of cell density. Extending our analysis to breast cancer cell lines with increasing invasiveness, we find that malignant cells exhibit longer phase persistence and fewer topological defects, suggesting a mechanistic link between temporal coherence and metastatic potential. Together, these results highlight the role of density-dependent synchrony dynamics as a fundamental, quantifiable mode of collective behavior in active epithelial matter, with implications for morphogenesis, cancer progression, and tissue diagnostics.