Comparison of two mouse ameloblast-like cell lines for enamel-specific gene expression.

Ameloblasts are ectoderm-derived cells that produce an extracellular enamel matrix that mineralizes to form enamel. The development and use of immortalized cell lines, with a stable phenotype, is an important contribution to biological studies as it allows for the investigation of molecular activities without the continuous need for animals. In this study we compare the expression profiles of enamel-specific genes in two mouse derived ameloblast-like cell lines: LS8 and ALC cells. Quantitative PCR analysis indicates that, relative to each other, LS8 cells express greater mRNA levels for genes that define secretory-stage activities (Amelx, Ambn, Enam, and Mmp20), while ALC express greater mRNA levels for genes that define maturation-stage activities (Odam and Klk4). Western blot analyses show that Amelx, Ambn, and Odam proteins are detectable in ALC, but not LS8 cells. Unstimulated ALC cells form calcified nodules, while LS8 cells do not. These data provide greater insight as to the suitability of both cell lines to contribute to biological studies on enamel formation and biomineralization, and highlight some of the strengths and weaknesses when relying on enamel epithelial organ-derived cell lines to study molecular activities of amelogenesis.

成釉细胞是外胚层衍生的细胞，它们产生细胞外釉质基质，该基质矿化形成釉质。具有稳定表型的永生化细胞系的开发和使用对生物学研究是一项重要贡献，因为它允许在不需要持续使用动物的情况下对分子活动进行研究。在这项研究中，我们比较了两种源自小鼠的成釉细胞样细胞系（LS8和ALC细胞）中釉质特异性基因的表达谱。定量PCR分析表明，相对于彼此，LS8细胞表达更高水平的定义分泌期活动的基因（Amelx、Ambn、Enam和Mmp20）的mRNA，而ALC细胞表达更高水平的定义成熟期活动的基因（Odam和Klk4）的mRNA。蛋白质印迹分析显示，Amelx、Ambn和Odam蛋白在ALC细胞中可检测到，但在LS8细胞中检测不到。未受刺激的ALC细胞形成钙化结节，而LS8细胞则不会。这些数据使我们更深入地了解了这两种细胞系对釉质形成和生物矿化生物学研究的适用性，并突出了在依靠釉质上皮器官衍生的细胞系研究成釉过程分子活动时的一些优势和劣势。