Single Cell Transcriptomes, Lineage, and Differentiation of Functional Airway Microfold Cells.
Single Cell Transcriptomes, Lineage, and Differentiation of Functional Airway Microfold Cells.
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功能性气道微褶皱细胞的单细胞转录组、谱系和分化。
DOI：
10.1101/2023.08.06.552176
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Rajagopal,Jayaraj
中科院分区：
文献类型：
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作者：
Surve,ManaleeV;Lin,Brian;Reedy,JenniferL;Crossen,ArianneJ;Xu,Anthony;Klein,BruceS;Vyas,JatinM;Rajagopal,Jayaraj
对气道内内容物取样的细胞仍然不完全确定。在肠道中，微折叠(M)细胞长期以来一直被认为专门吸收肠道内容物，随后它们将其内吞的货物转移到肠道相关淋巴组织的免疫细胞，经典地称为Peyeres斑块（1-4）。在上呼吸道，M细胞位于鼻相关淋巴组织附近（5-7），但它们在正常肺中的存在尚不确定。然后，在2019年，使用小鼠炎症模型明确证明可以诱导肺M细胞，并且它们与伴随诱导的支气管相关淋巴组织相关(8)。鉴于最近发现的气道上皮M细胞，控制其分化和发育起源的关键信号通路尚未被描述。尽管小鼠气道炎症明显导致大量气道M细胞的分化(8)，但我们推断，稳态M细胞可能由于其稀缺性而未引起注意，就像难以捉摸的肺离子细胞一样(9)。因此，我们重新分析了先前包含69,607个小鼠气管上皮细胞的单细胞转录组学数据(9)，并探索了典型的M细胞标记物。我们发现了一组我们之前错误标注的上皮细胞（数据补充中的图E1A）。该集群的特征是经典M细胞标记基因的表达，包括Spib和Sox8转录因子，趋化因子Ccl9和Ccl20，以及Tnfrsf11a (NF-κB受体激活因子；RANK)，已知其参与肠道M细胞分化（10）（图1A和E1B和表E1）。我们还发现了细菌摄取受体基因Gp2(4)和一系列与肠道M细胞相关的基因，包括Tnfaip2、Marcksl1和Anxa5（图1A）(1)。我们之前错误地将这些M细胞称为免疫细胞，因为由于它们共享趋化因子表达，它们与免疫细胞群聚集在一起。事实上，我们在69,607个气道上皮细胞中仅鉴定出58个M细胞，即使与离子细胞、神经内分泌细胞和簇状细胞相比，M细胞也是气道上皮中最稀少的细胞群（0.08%）（见图E1C）(9)。在肠道中，通过非典型NF-κB通路的RANK信号足以诱导M细胞从lgr5阳性肠道干细胞分化（10,11）。事实上，气道M细胞是在RANKL （RANK配体）诱导下首次被鉴定出来的（6,8）。在肠道中，TNF-α-诱导的典型NF-κB通路信号与rankl介导的非典型NF-κB通路激活协同作用，进一步促进M细胞分化（12）。考虑到这些分化途径在肠道和气道中是保守的，我们假设TNF-α可能会增强rankl诱导的气道
The cells that sample the luminal contents of the airway remain incompletely defined. In the gut, microfold (M) cells have long been known to specialize in the uptake of luminal contents, and they subsequently transfer their endocytosed cargo to the immune cells of gut-associated lymphoid tissue, classically known as Peyeres patches (1-4). In the upper airway, M cells are located adjacent to nasalassociated lymphoid tissues (5-7), but their presence in the normal lung remained uncertain. Then, in 2019, murine inflammatory models were used to definitively demonstrate that lung M cells could be induced and that they were associated with concomitantly induced bronchus-associated lymphoid tissue (8). Given the very recent discovery of airway epithelial M cells, the key signaling pathways governing their differentiation and developmental origins have not been delineated.Although murine airway inflammation clearly resulted in the differentiation of abundant airway M cells (8), we reasoned that homeostatic M cells might have escaped attention as a result of their scarcity, as was the case with the elusive pulmonary ionocyte (9). Therefore, we reanalyzed our prior single-cell transcriptomic data containing 69,607 murine tracheal epithelial cells (9) and probed for canonical M cell markers. We uncovered a cluster of epithelial cells that we had previously misannotated (Figure E1A in the data supplement). This cluster is characterized by the expression of classical M cell marker genes, including the Spib and Sox8 transcription factors, the chemokines Ccl9 and Ccl20, and Tnfrsf11a (the receptor activator of NF-κB; RANK), which is known to be involved in gut M cell differentiation (10)(Figures 1A and E1B and Table E1). We also identified the bacterial uptake receptor genes Gp2 (4) and a host of genes associated with gut M cells, including Tnfaip2, Marcksl1, and Anxa5 (Figure 1A)(1). We previously miscalled these M cells as immune cells because they had been clustered together with immune cell populations as a result of their shared chemokine expression. Indeed, we identified only 58 M cells among 69,607 airway epithelial cells, making them the single most scarce population in the airway epithelium (0.08%) even when compared with ionocytes, neuroendocrine cells, and tuft cells (see Figure E1C)(9). In the gut, RANK signaling through the noncanonical NF-κB pathway is sufficient to induce M cell differentiation from Lgr5-positive intestinal stem cells (10, 11). Indeed, airway M cells were first identified following RANKL (RANK ligand) induction (6, 8). In the gut, TNF-α-induced canonical NF-κB pathway signaling cooperates with RANKL-mediated noncanonical NF-κB pathway activation to further increase M cell differentiation (12). Reasoning that these pathways of differentiation would be conserved in the gut and airway, we hypothesized that TNF-α might enhance RANKL-induced airway