Data Sheet 1_A multimodal microfluidic-based platform integrating topographical and equibiaxial mechanical cues for next-generation in vitro cell microenvironment mimicking.pdf

The cellular microenvironment is a powerful regulator of the cell state and function. Both biochemical and morphophysical environmental cues have been shown to profoundly influence cellular decisions. However, the fundamental principles governing the intricate crosstalk between microenvironmental manipulation and the modulation of cell functions remain largely elusive. To unravel the regulatory role of the microenvironment in determining cellular fate and state, it is essential to develop tools capable of precisely presenting and integrating these signals. In this context, we propose a next-generation cell culture system that synergistically combines microfluidic and biomechanical platforms. This system is designed to systematically deliver microenvironmental stimuli to condition cell state. As a notable use case, we selected cardiomyocytes (CMs) given the well-documented influence of biochemical and morphophysical cues on cardiac tissue homeostasis. The platform features a multilayer design integrating complex mechanical stimulation, such as equibiaxial strain, on a deformable membrane equipped with microchannels for nutrient delivery. A radial micropattern was fabricated on the membrane to guide cell alignment along the direction of stretching, thereby homogenizing cellular response. The functionality of the device was first validated through COMSOL simulations and subsequently experimentally tested to confirm the interplay between equibiaxial mechanical stimulation and fluid flow. When HL-1 rat atrial CMs were seeded on the platform, they proliferated, aligned with the micropattern, and exhibited persistent migration along the stretching direction under equibiaxial deformation. These findings demonstrate that the combination of microenvironmental signals is critical for enhancing cellular activity and underscore the importance of accurately replicating the cell microenvironment in lab-on-chip applications.

细胞微环境（cellular microenvironment）是调控细胞状态与功能的强效调控因子。生物化学与形态物理层面的环境信号，均已被证实会对细胞命运决策产生深远影响。然而，介导微环境干预与细胞功能调控之间复杂串扰的核心原理，目前仍在很大程度上不甚明晰。为了揭示微环境在决定细胞命运与状态中的调控作用，开发能够精准呈现并整合这些信号的工具至关重要。在此背景下，本研究提出一种新一代细胞培养系统，该系统协同集成了微流控平台（microfluidic platforms）与生物力学平台（biomechanical platforms）。本系统旨在系统性地递送微环境刺激，以调控细胞状态。作为典型应用场景，我们选取了心肌细胞（cardiomyocytes, CMs）进行研究，这是因为生物化学与形态物理信号对心脏组织稳态的影响已有充分文献记载。该平台采用多层设计，在配备用于营养输送的微通道的可变形膜上，集成了等双轴应变（equibiaxial strain）等复杂力学刺激。研究人员在膜上制备了径向微图案（radial micropattern），以引导细胞沿拉伸方向对齐，从而实现细胞响应的均一化。该装置的功能首先通过COMSOL仿真进行验证，随后通过实验测试证实了等双轴力学刺激与流体流动之间的相互作用。当将HL-1大鼠心房心肌细胞接种至该平台后，细胞发生增殖、沿微图案对齐，并在等双轴形变条件下沿拉伸方向持续迁移。上述研究结果表明，微环境信号的协同组合对增强细胞活性至关重要，同时也凸显了在芯片实验室（lab-on-chip）应用中精准复现细胞微环境的重要性。