Department of Materials, Imperial College London, London, United Kingdom.
Biophys J. 2010 Apr 21;98(8):1703-11. doi: 10.1016/j.bpj.2009.12.4289.
Researchers have previously questioned the suitability of cell lines as models for primary cells. In this study, we used Raman microspectroscopy to characterize live A549 cells from a unique molecular biochemical perspective to shed light on their suitability as a model for primary human pulmonary alveolar type II (ATII) cells. We also investigated a recently developed transduced type I (TT1) cell line as a model for alveolar type I (ATI) cells. Single-cell Raman spectra provide unique biomolecular fingerprints that can be used to characterize cellular phenotypes. A multivariate statistical analysis of Raman spectra indicated that the spectra of A549 and TT1 cells are characterized by significantly lower phospholipid content compared to ATII and ATI spectra because their cytoplasm contains fewer surfactant lamellar bodies. Furthermore, we found that A549 spectra are statistically more similar to ATI spectra than to ATII spectra. The spectral variation permitted phenotypic classification of cells based on Raman spectral signatures with >99% accuracy. These results suggest that A549 cells are not a good model for ATII cells, but TT1 cells do provide a reasonable model for ATI cells. The findings have far-reaching implications for the assessment of cell lines as suitable primary cellular models in live cultures.
研究人员先前曾质疑细胞系作为原代细胞模型的适用性。在这项研究中，我们使用拉曼微光谱技术从独特的分子生化角度对活的 A549 细胞进行了特征描述，以期阐明其作为原代人肺Ⅱ型肺泡（ATII）细胞模型的适用性。我们还研究了最近开发的转导Ⅰ型（TT1）细胞系作为Ⅰ型肺泡（ATI）细胞模型的适用性。单细胞拉曼光谱提供了独特的生物分子指纹，可以用于表征细胞表型。拉曼光谱的多元统计分析表明，与 ATII 和 ATI 光谱相比，A549 和 TT1 细胞的光谱特征是由于其细胞质中含有较少的表面活性剂板层小体，因此磷脂含量明显较低。此外，我们发现 A549 光谱在统计学上与 ATI 光谱比与 ATII 光谱更相似。基于拉曼光谱特征的表型分类可以实现细胞的分类，准确率>99%。这些结果表明，A549 细胞不是 ATII 细胞的良好模型，但 TT1 细胞确实为 ATI 细胞提供了合理的模型。这些发现对评估细胞系作为活培养中合适的原代细胞模型具有深远的意义。
