McDonnell Emily E, Buckley Conor T
Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin The University of Dublin Dublin Ireland.
Discipline of Mechanical, Manufacturing and Biomedical Engineering, School of Engineering, Trinity College Dublin The University of Dublin Dublin Ireland.
JOR Spine. 2022 Aug 30;5(3):e1222. doi: 10.1002/jsp2.1222. eCollection 2022 Sep.
It is well established that the unique biochemical microenvironment of the intervertebral disc plays a predominant role in cell viability and biosynthesis. However, unless the effect of microenvironmental conditions is primary to a study objective, in vitro culture parameters that are critical for reproducibility are both varied and not routinely reported.
This work aims to investigate the local microenvironments of commonly used culture configurations, highlighting physiological relevance, potential discrepancies, and elucidating possible heterogeneity across the research field.
This work uses nutrient-transport in silico models to reflect on the effect of often underappreciated parameters, such as culture geometry and diffusional distance (vessel, media volume, construct size), seeding density, and external boundary conditions on the local microenvironment of two-dimensional (2D) and three-dimensional (3D) in vitro culture systems.
We elucidate important discrepancies between the external boundary conditions such as the incubator level or media concentrations and the actual local cellular concentrations. Oxygen concentration and cell seeding density were found to be highly influential parameters and require utmost consideration when utilizing 3D culture systems.
This work highlights that large variations in the local nutrient microenvironment can easily be established without consideration of several key parameters. Without careful deliberation of the microenvironment within each specific and unique system, there is the potential to confound in vitro results leading to heterogeneous results across the research field in terms of biosynthesis and matrix composition.
Overall, this calls for a greater appreciation of key parameters when designing in vitro experiments. Better harmony and standardization of physiologically relevant local microenvironments are needed to push toward reproducibility and successful translation of findings across the research field.
众所周知，椎间盘独特的生化微环境在细胞活力和生物合成中起主要作用。然而，除非微环境条件的影响是研究目标的首要因素，否则对于可重复性至关重要的体外培养参数既多样又未被常规报道。
本研究旨在探究常用培养配置的局部微环境，突出其生理相关性、潜在差异，并阐明整个研究领域可能存在的异质性。
本研究使用营养物质传输的计算机模拟模型，以反映诸如培养几何形状和扩散距离（容器、培养基体积、构建体大小）、接种密度以及外部边界条件等常被忽视的参数对二维（2D）和三维（3D）体外培养系统局部微环境的影响。
我们阐明了诸如培养箱水平或培养基浓度等外部边界条件与实际局部细胞浓度之间的重要差异。发现氧浓度和细胞接种密度是极具影响力的参数，在使用3D培养系统时需要充分考虑。
本研究强调，如果不考虑几个关键参数，局部营养微环境很容易出现巨大差异。如果不仔细考虑每个特定且独特系统中的微环境，就有可能混淆体外实验结果，导致整个研究领域在生物合成和基质组成方面出现异质性结果。
总体而言，这要求在设计体外实验时更加重视关键参数。需要更好地协调和标准化生理相关的局部微环境，以推动研究结果在整个研究领域的可重复性和成功转化。
