Department of Stem Cell and Developmental Biology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, 514-8507, Japan.
Cell Mol Life Sci. 2022 Feb 27;79(3):159. doi: 10.1007/s00018-022-04203-7.
Yolk sac (YS) CSF1 receptor positive (CSF1R) cells are thought to be the progenitors for tissue-resident macrophages present in various tissues. The YS progenitors for tissue-resident macrophages are referred to as erythroid-myeloid progenitors (EMPs). However, diverse types of hematopoietic progenitors are present in the early YS, thus it is not precisely known which type of hematopoietic cell gives rise to the CSF1R lineage. In this study, an analysis was conducted to determine when CSF1R progenitors appeared in the early YS. It showed that CSF1R cells appeared in the YS as early as embryonic day 9 (E9) and that the earliest hematopoietic progenitors that differentiate into CSF1R cells were found in E8. Since these progenitors possessed the capability to generate primitive erythroid cells, it was likely that primitive erythroid lineages shared progenitors with the CSF1R lineage. Mutual antagonism appears to work between PU.1 and GATA1 when CSF1R cells appear in the early YS. One day later (E9), multiple progenitors, including myeloid-restricted progenitors and multipotent progenitors, in the YS could immediately generate CSF1R cells. These results suggest that EMPs are not an exclusive source for the CSF1R lineage; rather, multiple hematopoietic cell populations give rise to CSF1R lineage in the early YS.
卵黄囊 (YS) CSF1 受体阳性 (CSF1R) 细胞被认为是存在于各种组织中的组织驻留巨噬细胞的祖细胞。组织驻留巨噬细胞的 YS 祖细胞被称为红系-髓系祖细胞 (EMPs)。然而，早期 YS 中存在多种类型的造血祖细胞，因此尚不清楚哪种类型的造血细胞会产生 CSF1R 谱系。在这项研究中，分析了 CSF1R 祖细胞何时出现在早期 YS 中。结果表明，CSF1R 细胞早在胚胎第 9 天 (E9) 就出现在 YS 中，最早分化为 CSF1R 细胞的造血祖细胞出现在 E8。由于这些祖细胞具有生成原始红细胞的能力，因此原始红细胞谱系可能与 CSF1R 谱系共享祖细胞。当 CSF1R 细胞出现在早期 YS 中时，PU.1 和 GATA1 之间似乎存在相互拮抗作用。一天后 (E9)，YS 中的多种祖细胞，包括髓系限制祖细胞和多能祖细胞，能够立即产生 CSF1R 细胞。这些结果表明，EMPs 不是 CSF1R 谱系的唯一来源；相反，多种造血细胞群体在早期 YS 中产生 CSF1R 谱系。
