Department of Chemical and Biomolecular Engineering and Johns Hopkins Physical Sciences-Oncology Center, Johns Hopkins University, 3400 N Charles St., Baltimore, MD 21218, USA.
Biomed Microdevices. 2012 Feb;14(1):145-52. doi: 10.1007/s10544-011-9592-9.
The ability to control the oxygen level to which cells are exposed in tissue culture experiments is crucial for many applications. Here, we design, develop and test a microbioreactor (MBR) for long-term cell culture studies with the capability to accurately control and continuously monitor the dissolved oxygen (DO) level in the cell microenvironment. In addition, the DO level can be controlled independently from other cues, such as the viscous shear-stress acting on the cells. We first analyze the transport of oxygen in the proposed device and determine the materials and dimensions that are compatible with uniform oxygen tension and low shear-stress at the cell level. The device is also designed to culture a statistically significant number of cells. We use fully transparent materials and the overall design of the device is compatible with live-cell imaging. The proposed system includes real-time read-out of actual DO levels, is simple to fabricate at low cost, and can be easily expanded to control the concentration of other microenvironmental solutes. We performed control experiments in the absence of cells to demonstrate that the MBR can be used to accurately modulate DO levels ranging from atmospheric level to 1%, both under no flow and perfusion conditions. We also demonstrate cancer cell attachment and viability within the MBR. The proposed MBR offers the unprecedented capability to perform on-line measurement and analysis of DO levels in the microenvironment of adherent cultures and to correlate them with various cellular responses.
在组织培养实验中控制细胞暴露于氧气水平的能力对于许多应用至关重要。在这里，我们设计、开发和测试了一种用于长期细胞培养研究的微生物反应器（MBR），该反应器具有精确控制和连续监测细胞微环境中溶解氧（DO）水平的能力。此外，DO 水平可以独立于其他信号（如作用于细胞的粘性剪切应力）进行控制。我们首先分析了所提出的设备中的氧气传输，并确定了与细胞水平的均匀氧张力和低剪切应力兼容的材料和尺寸。该设备还设计用于培养具有统计学意义数量的细胞。我们使用全透明材料，并且设备的整体设计与活细胞成像兼容。所提出的系统包括对实际 DO 水平的实时读取，制造简单且成本低，并可轻松扩展以控制其他微环境溶质的浓度。我们在没有细胞的情况下进行了控制实验，以证明 MBR 可用于在无流动和灌注条件下精确调节从大气水平到 1%的 DO 水平。我们还在 MBR 内展示了癌细胞的附着和活力。所提出的 MBR 提供了在线测量和分析贴壁培养物微环境中 DO 水平的前所未有的能力，并将其与各种细胞反应相关联。
