Defining the mechanisms that generate specialized cell types and coordinate their functions is critical for understanding organ development and renewal. New tools and discoveries are challenging and refining our definitions of a cell type. A rapidly growing toolkit for single-cell analyses has expanded the number of markers that can be assigned to a cell simultaneously, revealing heterogeneity within cell types that were previously regarded as homogeneous populations. Additionally, cell types defined by specific molecular markers can exhibit distinct, context-dependent functions; for example, between tissues in homeostasis and those responding to damage. Here we review the current technologies used to identify and characterize cells, and we discuss how experimental and pathological perturbations are adding increasing complexity to our definitions of cell identity.

中文翻译：

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用于询问和定义细胞身份的工具和概念。


定义产生特殊细胞类型并协调其功能的机制对于理解器官发育和更新至关重要。新的工具和发现正在挑战和完善我们对细胞类型的定义。快速发展的单细胞分析工具包扩大了可同时分配给细胞的标记数量，揭示了以前被视为同质群体的细胞类型内的异质性。此外，由特定分子标记定义的细胞类型可以表现出独特的、依赖于背景的功能；例如，处于稳态的组织和对损伤做出反应的组织之间。在这里，我们回顾了当前用于识别和表征细胞的技术，并讨论了实验和病理扰动如何增加我们对细胞身份的定义的复杂性。