The Human Testis Cell Atlas via Single-cell RNA-seq (Infant scRNA-seq data set). The Human Testis Cell Atlas via Single-cell RNA-seq (Infant scRNA-seq data set)

Human adult spermatogenesis involves a balance of spermatogonial stem cell self renewal and differentiation, alongside complex germline-niche interactions. To better understand, we performed single cell RNA sequencing of ~7000 testis cells from three healthy men of peak reproductive age. Our analyses revealed multiple distinctive transcriptional ‘states’ of self-renewing and differentiating spermatogonia, the cellular stages of gametogenesis, five niche cells (Leydig, Myoid, Sertoli, Endothelial, macrophage) and insights into germline-niche communication. Spermatogenesis was reconstructed computationally, which identified sequential coding, noncoding, and repeat-element transcriptional signatures. A new, developmentally early and likely quiescent spermatogonial state is identified (GFRA1-/ETV5-/ID4+/UTF1+/FGFR3+). Notably, certain epigenetic features combined with nascent transcription analyses suggest considerable plasticity within certain spermatogonial populations/states. Key findings were validated via RNA and protein staining. Taken together, we provided the first “Cell Atlas” of the adult human testis, and provide multiple new insights into germ cell development and germ cell – niche interaction. Overall design: We isolated single testicular cell from two infant (13 months old). Two technical replicates were performed for each individual.

人类成年精子发生过程需维持精原干细胞（spermatogonial stem cell）自我更新与分化的动态平衡，同时伴随复杂的生殖细胞龛（germline niche）互作。为深入解析该生物学过程，我们对3名处于生殖巅峰年龄的健康男性的约7000个睾丸细胞开展了单细胞RNA测序。分析结果揭示了自我更新型与分化型精原细胞——配子发生（gametogenesis）的核心细胞阶段——的多种特征性转录状态，同时鉴定出5类龛细胞：莱迪希细胞（Leydig）、肌样细胞（Myoid）、支持细胞（Sertoli）、内皮细胞（Endothelial）与巨噬细胞（macrophage），并为生殖细胞-龛互作提供了全新视角。我们通过计算建模重构了精子发生过程，鉴定出其依次呈现的编码基因、非编码基因以及重复元件的转录特征谱。本研究还鉴定出一种全新的发育早期且大概率处于静息状态的精原细胞状态（GFRA1-/ETV5-/ID4+/UTF1+/FGFR3+）。值得注意的是，结合表观遗传特征与新生转录本分析的结果表明，部分精原细胞群体/状态具备显著的细胞可塑性。核心研究结论均通过RNA与蛋白质染色实验得到了独立验证。综上，本研究构建了首个成人睾丸细胞图谱（Cell Atlas），并为生殖细胞发育以及生殖细胞-龛互作领域提供了多项突破性见解。实验设计概述：我们从2名13月龄的婴儿体内分离出单个睾丸细胞，每名个体均设置2次技术重复。