Department of Biomedical Engineering, Rutgers University, Piscataway, NJ, USA.
Cell Cycle. 2010 Jun 1;9(11):2108-17. doi: 10.4161/cc.9.11.11864.
Our recent report suggests that subtle changes in early cytoskeletal protein-level organization correlate with long-term stem cell lineage commitment. In this extra-view, we dissect changes in the expression of both cytoskeletal and nuclear-regulating genes that may precede and, possibly, govern the formative lineage-specific organizational cues. Human mesenchymal stem cells cultured on glass under basal, osteogenic, and adipogenic induction media were analyzed for gene expression profiles within the first 24 hours. Several key actin organization regulating genes and nuclear and cell cycle regulatory genes were found to be upregulated in osteogenic media compared to adipogenic and basal conditions. Given the role of both cytoskeletal and nuclear genes, we examined the possibility of classifying stem cell subpopulations using high content imaging approaches based on the organization of both actin, as previously proposed, as well as nuclear organization and distribution of a nuclear organizational protein, the nuclear mitotic apparatus (NuMA). A pool of combined cytoskeletal and nuclear descriptors were merged into a composite feature space via dimensionality reduction, data fusion, and classification methodologies. This composite approach enabled feature-based identification of specific lineage committed as well as non-differentiating cell populations. Using the improved classification of this high-content imaging-based profiling tool, we demonstrate that MSCs induced to differentiate to either osteogenic or adipogenic lineages are discernable within the first 24 hours from each other and from non-differentiating cells.
我们最近的报告表明，早期细胞骨架蛋白水平组织的细微变化与长期干细胞谱系分化有关。在这篇额外的观点文章中，我们剖析了细胞骨架和核调节基因表达的变化，这些变化可能先于并可能支配形成谱系特异性的组织线索。在基础、成骨和脂肪诱导培养基中培养的人骨髓间充质干细胞在最初的 24 小时内分析了基因表达谱。与脂肪形成条件和基础条件相比，在成骨培养基中发现了几个关键的肌动蛋白组织调节基因和核及细胞周期调节基因上调。鉴于细胞骨架和核基因的作用，我们研究了使用高内涵成像方法基于肌动蛋白组织（如前所述）以及核组织和核组织蛋白核有丝分裂装置（NuMA）的核分布来对干细胞亚群进行分类的可能性。通过降维、数据融合和分类方法将一组组合的细胞骨架和核描述符合并到复合特征空间中。这种组合方法能够基于特征识别特定的谱系定向以及非分化细胞群体。使用这种基于高内涵成像的分析工具的改进分类，我们证明在最初的 24 小时内，诱导分化为成骨或脂肪谱系的 MSC 彼此之间以及与非分化细胞之间是可区分的。
