Abstract：
The cleavage of zygotes generates totipotent blastomeres. In human 8-cell blastomeres, zygotic genome activation (ZGA) occurs to initiate the ontogenesis program. However, capturing and maintaining totipotency in human cells pose significant challenges. Here, we realize culturing human totipotent blastomere-like cells (hTBLCs). We find that splicing inhibition can transiently reprogram human pluripotent stem cells into ZGA-like cells (ZLCs), which subsequently transition into stable hTBLCs after long-term passaging. Distinct from reported 8-cell-like cells (8CLCs), both ZLCs and hTBLCs widely silence pluripotent genes. Interestingly, ZLCs activate a particular group of ZGA-specific genes, and hTBLCs are enriched with pre-ZGA-specific genes. During spontaneous differentiation, hTBLCs re-enter the intermediate ZLC stage and further generate epiblast (EPI)-, primitive endoderm (PrE)-, and trophectoderm (TE)-like lineages, effectively recapitulating human pre-implantation development. Possessing both embryonic and extraembryonic developmental potency, hTBLCs can autonomously generate blastocyst-like structures in vitro without external cell signaling. In summary, our study provides key criteria and insights into human cell totipotency.
摘要：
受精卵的分裂产生全能卵裂球。在人类8细胞卵裂球中，发生合子基因组激活（ZGA）以启动个体发育程序。然而,在人体细胞中捕获和维持全能性构成了重大挑战。这里,我们实现了培养人类全能卵裂球样细胞（hTBLC）。我们发现剪接抑制可以将人类多能干细胞瞬时重编程为ZGA样细胞（ZLCs），其随后在长期传代后转变为稳定的hTBLC。与报道的8细胞样细胞（8CLC）不同，ZLC和hTBLC都广泛沉默多能基因。有趣的是,ZLCs激活一组特定的ZGA特异性基因，和hTBLC富含前ZGA特异性基因。在自发分化过程中,hTBLC重新进入中间ZLC阶段，并进一步产生外爆炸（EPI）-，原始内胚层（PrE）-，和类似滋养外胚层（TE）的谱系，有效地概括了人类植入前的发育。具有胚胎和胚胎外发育能力，hTBLC可以在体外自主产生胚泡样结构而没有外部细胞信号传导。总之,我们的研究提供了人类细胞全能性的关键标准和见解.
