Department of Mechanical and Aerospace Engineering, The George Washington University School of Engineering and Applied Science, Washington, DC, USA.
Section on Mechanobiology, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA.
Commun Biol. 2022 Jan 11;5(1):17. doi: 10.1038/s42003-021-02959-5.
Countless biophysical studies have sought distinct markers in the cellular mechanical response that could be linked to morphogenesis, homeostasis, and disease. Here, an iterative-fitting methodology visualizes the time-dependent viscoelastic behavior of human skin cells under physiologically relevant conditions. Past investigations often involved parameterizing elastic relationships and assuming purely Hertzian contact mechanics, which fails to properly account for the rich temporal information available. We demonstrate the performance superiority of the proposed iterative viscoelastic characterization method over standard open-search approaches. Our viscoelastic measurements revealed that 2D adherent metastatic melanoma cells exhibit reduced elasticity compared to their normal counterparts-melanocytes and fibroblasts, and are significantly less viscous than fibroblasts over timescales spanning three orders of magnitude. The measured loss angle indicates clear differential viscoelastic responses across multiple timescales between the measured cells. This method provides insight into the complex viscoelastic behavior of metastatic melanoma cells relevant to better understanding cancer metastasis and aggression.
无数生物物理研究都在寻找细胞力学响应中的独特标志物，这些标志物可能与形态发生、内稳态和疾病有关。在这里，一种迭代拟合方法可视化了在生理相关条件下人类皮肤细胞的时变黏弹性行为。过去的研究通常涉及参数化弹性关系和假设纯赫兹接触力学，这不能正确地解释可用的丰富时间信息。我们证明了所提出的迭代黏弹性特征化方法优于标准的开放式搜索方法的性能优势。我们的黏弹性测量结果表明，与正常细胞（黑素细胞和成纤维细胞）相比，二维贴壁转移性黑素瘤细胞的弹性降低，并且在跨越三个数量级的时间尺度上，其粘性明显低于成纤维细胞。测量的损耗角表明，在测量的细胞之间，多个时间尺度上存在明显的差异黏弹性响应。这种方法提供了对转移性黑素瘤细胞复杂黏弹性行为的深入了解，有助于更好地理解癌症转移和侵袭。
