AI 中文总结
本研究结合实验与模拟发现，致密HeLa细胞单层在强拥挤下仍保持液态弛豫，持续运动性是维持高密度结构弛豫的关键，为癌症转移提供启示。
AI 中文摘要
致密细胞单层中的集体动力学由拥挤与细胞运动性之间的相互作用所控制。尽管增加密度可以减缓细胞运动并促进类玻璃行为，但致密HeLa单层的动力学状态仍不清楚。在此，我们将HeLa细胞单层的体外延时成像与可变形活性细胞模型的模拟相结合，以研究细胞密度和运动性如何调节集体弛豫。在实验可及的密度和时间范围内，未经处理的HeLa单层保持液态：结构弛豫随密度增加而逐渐减慢，但在整个研究范围内仍可观察到。在低营养条件下，细胞运动性大幅降低，结构弛豫变得显著更慢。为了阐明这些实验观察背后的机制，我们进一步使用可变形细胞模型进行了模拟。该模型定性地重现了结构弛豫时间随密度增加的现象，并进一步表明，在高堆积分数下，降低自推进力会促进长寿命的笼蔽动力学。这些结果表明，致密HeLa单层在未经处理的条件下能够维持缓慢、异质但仍可弛豫的集体动力学，并表明持续性的细胞运动性是维持高密度下结构弛豫的重要因素，这可能为癌细胞的转移潜能提供见解。
英文摘要
Collective dynamics in dense cell monolayers are governed by the interplay between crowding and cellular motility. Although increasing density can slow cellular motion and promote glass-like behaviour, the dynamical state of dense HeLa monolayers remains unclear. Here, we combine in vitro time-lapse imaging of HeLa cell monolayers with simulations of a deformable active-cell model to examine how cell density and motility regulate collective relaxation. Within the experimentally accessible density and time ranges, untreated HeLa monolayers remain liquid-like: structural relaxation progressively slows down with increasing density but remains observable throughout the investigated range. Under low-nutrient conditions, cell motility is strongly reduced, and structural relaxation becomes substantially slower. To elucidate the mechanisms underlying these experimental observations, we further performed simulations using a deformable-cell model. The model qualitatively reproduces the density-dependent increase in structural relaxation time and further shows that reducing self-propulsion promotes long-lived caging dynamics at high packing fractions. These results show that dense HeLa monolayers can sustain slow, heterogeneous, yet relaxing collective dynamics under untreated conditions, and indicate that persistent cellular motility is an important factor in maintaining structural relaxation at high density, which may provide insight into the metastatic potential of cancer cells.
Comments15 pages, 4 main figures, 1 supplementary figure
