The heart, which is the first organ to develop, is highly dependent on its form to function^1,2. However, how diverse cardiac cell types spatially coordinate to create the complex morphological structures that are crucial for heart function remains unclear. Here we integrated single-cell RNA-sequencing with high-resolution multiplexed error-robust fluorescence in situ hybridization to resolve the identity of the cardiac cell types that develop the human heart. This approach also provided a spatial mapping of individual cells that enables illumination of their organization into cellular communities that form distinct cardiac structures. We discovered that many of these cardiac cell types further specified into subpopulations exclusive to specific communities, which support their specialization according to the cellular ecosystem and anatomical region. In particular, ventricular cardiomyocyte subpopulations displayed an unexpected complex laminar organization across the ventricular wall and formed, with other cell subpopulations, several cellular communities. Interrogating cell–cell interactions within these communities using in vivo conditional genetic mouse models and in vitro human pluripotent stem cell systems revealed multicellular signalling pathways that orchestrate the spatial organization of cardiac cell subpopulations during ventricular wall morphogenesis. These detailed findings into the cellular social interactions and specialization of cardiac cell types constructing and remodelling the human heart offer new insights into structural heart diseases and the engineering of complex multicellular tissues for human heart repair.

心脏是第一个发育的器官，其功能高度依赖于其形态^1,2。然而，不同的心脏细胞类型如何在空间上协调以创建对心脏功能至关重要的复杂形态结构仍不清楚。在这里，我们将单细胞 RNA 测序与高分辨率多重抗误差荧光原位杂交相结合，以解析发育人类心脏的心脏细胞类型的身份。这种方法还提供了单个细胞的空间映射，从而能够将其组织照明到形成不同心脏结构的细胞群落中。我们发现，许多心脏细胞类型进一步被指定为特定群落独有的亚群，这支持它们根据细胞生态系统和解剖区域的专业化。特别是，心室心肌细胞亚群在心室壁上表现出意想不到的复杂层状组织，并与其他细胞亚群一起形成了几个细胞群落。使用体内条件遗传小鼠模型和体外人类多能干细胞系统来探究这些群落内的细胞-细胞相互作用，揭示了在心室壁形态发生过程中协调心脏细胞亚群空间组织的多细胞信号传导途径。这些关于构建和重塑人类心脏的细胞社会相互作用和心肌细胞类型专业化的详细发现为结构性心脏病和用于人类心脏修复的复杂多细胞组织工程提供了新的见解。