Single-cell analysis is a valuable tool for dissecting cellular heterogeneity in complex systems¹. However, a comprehensive single-cell atlas has not been achieved for humans. Here we use single-cell mRNA sequencing to determine the cell-type composition of all major human organs and construct a scheme for the human cell landscape (HCL). We have uncovered a single-cell hierarchy for many tissues that have not been well characterized. We established a ‘single-cell HCL analysis’ pipeline that helps to define human cell identity. Finally, we performed a single-cell comparative analysis of landscapes from human and mouse to identify conserved genetic networks. We found that stem and progenitor cells exhibit strong transcriptomic stochasticity, whereas differentiated cells are more distinct. Our results provide a useful resource for the study of human biology.

单细胞分析是剖析复杂系统中细胞异质性的宝贵工具¹. 然而，人类尚未获得全面的单细胞图谱。在这里，我们使用单细胞 mRNA 测序来确定所有主要人体器官的细胞类型组成，并构建人类细胞景观 (HCL) 的方案。我们发现了许多尚未很好表征的组织的单细胞层次结构。我们建立了一个“单细胞 HCL 分析”管道，有助于定义人类细胞身份。最后，我们对人和小鼠的景观进行了单细胞比较分析，以确定保守的遗传网络。我们发现干细胞和祖细胞表现出很强的转录组随机性，而分化的细胞则更加明显。我们的研究结果为人类生物学研究提供了有用的资源。