Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, United States.
University of Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, United States.
Elife. 2020 Jun 1;9:e57438. doi: 10.7554/eLife.57438.
Tissue-resident macrophages in the mammary gland are found in close association with epithelial structures and within the adipose stroma, and are important for mammary gland development and tissue homeostasis. Macrophages have been linked to ductal development in the virgin mammary gland, but less is known regarding the effects of macrophages on the adipose stroma. Using transcriptional profiling and single-cell RNA sequencing approaches, we identify a distinct resident stromal macrophage subpopulation within the mouse nulliparous mammary gland that is characterized by the expression of Lyve-1, a receptor for the extracellular matrix (ECM) component hyaluronan. This subpopulation is enriched in genes associated with ECM remodeling and is specifically associated with hyaluronan-rich regions within the adipose stroma and fibrous capsule of the virgin mammary gland. Furthermore, macrophage depletion leads to enhanced accumulation of hyaluronan-associated ECM in the adipose-associated stroma, indicating that resident macrophages are important for maintaining homeostasis within the nulliparous mammary gland stroma.
乳腺组织驻留巨噬细胞与上皮结构密切相关，并存在于脂肪基质中，对乳腺发育和组织稳态至关重要。巨噬细胞与未孕乳腺的导管发育有关，但关于巨噬细胞对脂肪基质的影响知之甚少。我们使用转录谱和单细胞 RNA 测序方法，在未孕小鼠乳腺中鉴定出一种独特的驻留基质巨噬细胞亚群，其特征是表达 Lyve-1，这是细胞外基质（ECM）成分透明质酸的受体。这个亚群富含与 ECM 重塑相关的基因，并且与脂肪基质和未孕乳腺的纤维囊中的透明质酸丰富区域特异性相关。此外，巨噬细胞耗竭导致脂肪相关基质中透明质酸相关 ECM 的积累增加，表明驻留巨噬细胞对维持未孕乳腺基质的内稳态很重要。
