Olson Samuel, Finley McKenna, Thakur Raviraj
Cancer Early Detection Advanced Research Center (CEDAR), Knight Cancer Institute, Oregon Health & Science University, USA.
HardwareX. 2024 Oct 11;20:e00595. doi: 10.1016/j.ohx.2024.e00595. eCollection 2024 Dec.
Cells in the body are regularly subjected to mechanical forces that influence their biological fate in terms of morphology, gene expression, and differentiation. The current gold standard method to replicate these effects in vitro is to culture cells on devices with elastic substrates and to impart mechanical stretch using mechanical or pneumatic pull-push methods. Microfluidic device designs offer several advantages in this context for general uniform and controlled stretching. However, the experimental setups are bulky, not user-friendly, and often involve several components that reside outside of the tissue culture incubator. Given the wide utility of mechanical stimulation in in-vitro research, our aim was to create a turn-key research tool that bioengineers can deploy in their cell-stretch assays, without having to deal with the complexity and nuances of ad hoc experimental setups. Here, we present an open-source, battery-powered, dual-channel cyclic pneumatic pulse generator box that can reside within an incubator and is compatible with custom microfluidic cell stretch devices. Our method depends on generating pressure-vacuum pulses simply using a linear miniature pneumatic air cylinder actuated using a continuous servo motor. To the best our knowledge, this is a first example of a completely battery-powered, standalone system that doesn't have any peripherals residing out of the incubator. We provide a detailed list of different components as well as the step-by-step assembly process. We validate its performance in a cell stretch assay using a commercially available microfluidic chip. Our results show an acute stimulation of cyclic stretching over 8 h on human umbilical vein endothelial cells (HUVECs) resulted in preferential alignment of cells perpendicular to the axis of stretch.
体内的细胞经常受到机械力的作用，这些机械力在细胞形态、基因表达和分化方面影响着它们的生物学命运。目前在体外复制这些效应的金标准方法是将细胞培养在具有弹性基质的装置上，并使用机械或气动推拉方法施加机械拉伸。在这种情况下，微流控装置设计在实现一般均匀且可控的拉伸方面具有几个优点。然而，实验装置体积庞大，不便于用户使用，并且通常涉及位于组织培养箱外部的几个组件。鉴于机械刺激在体外研究中的广泛应用，我们的目标是创建一种交钥匙研究工具，生物工程师可以在他们的细胞拉伸试验中部署该工具，而无需处理临时实验装置的复杂性和细微差别。在此，我们展示了一种开源的、电池供电的双通道循环气动脉冲发生器箱，它可以放置在培养箱内，并与定制的微流控细胞拉伸装置兼容。我们的方法仅依靠使用由连续伺服电机驱动的线性微型气缸来产生压力 - 真空脉冲。据我们所知，这是一个完全由电池供电的独立系统的首个示例，该系统没有任何位于培养箱外部的外围设备。我们提供了不同组件的详细列表以及逐步组装过程。我们使用市售的微流控芯片在细胞拉伸试验中验证了其性能。我们的结果表明，在人脐静脉内皮细胞（HUVECs）上进行8小时的循环拉伸急性刺激导致细胞优先沿垂直于拉伸轴的方向排列。
