AUTHOR=Gao Hanchao , Cao Mengtao , Deng Kai , Yang Yang , Song Jinqi , Ni Ming , Xie Chuntao , Fan Wenna , Ou Chunpei , Huang Dinggen , Lin Lizhong , Liu Lixia , Li Yangyang , Sun Huimin , Cheng Xinyu , Wu Jinmei , Xia Cuilan , Deng Xuefeng , Mou Lisha , Chen Pengfei TITLE=The Lineage Differentiation and Dynamic Heterogeneity of Thymic Epithelial Cells During Thymus Organogenesis JOURNAL=Frontiers in Immunology VOLUME=13 YEAR=2022 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2022.805451 DOI=10.3389/fimmu.2022.805451 ISSN=1664-3224 ABSTRACT=

Although much progress has been made recently in revealing the heterogeneity of the thymic stromal components, the molecular programs of cell lineage divergency and temporal dynamics of thymic epithelial cell (TEC) development are largely elusive. Here, we constructed a single-cell transcriptional landscape of non-hematopoietic cells from mouse thymus spanning embryonic to adult stages, producing transcriptomes of 30,959 TECs. We resolved the transcriptional heterogeneity of developing TECs and highlighted the molecular nature of early TEC lineage determination and cortico-medullary thymic epithelial cell lineage divergency. We further characterized the differentiation dynamics of TECs by clarification of molecularly distinct cell states in the thymus developing trajectory. We also identified a population of Bpifa1+ Plet1+ mTECs that was preserved during thymus organogenesis and highly expressed tissue-resident adult stem cell markers. Finally, we highlighted the expression of Aire-dependent tissue-restricted antigens mainly in Aire+ Csn2+ mTECs and Spink5+ Dmkn+ mTECs in postnatal thymus. Overall, our data provided a comprehensive characterization of cell lineage differentiation, maturation, and temporal dynamics of thymic epithelial cells during thymus organogenesis.