Brown adipose tissue monocytes support tissue expansion.
Alexandre GallerandMarion I StunaultJohanna MerlinHannah P LuehmannDeborah H SultanMaria M FirulyovaVirginie MagnoneNarges KhedherAntoine JalilBastien DolfiAlexia CastiglioneAdelie DumontMarion AyraultNathalie VaillantJérôme GilleronPascal BarbryDavid DombrowiczMatthias MackDavid MassonThomas BerteroBurkhard BecherJesse W WilliamsKonstantin ZaitsevYongjian LiuRodolphe R GuinamardLaurent Yvan-CharvetStoyan IvanovPublished in: Nature communications (2021)
Monocytes are part of the mononuclear phagocytic system. Monocytes play a central role during inflammatory conditions and a better understanding of their dynamics might open therapeutic opportunities. In the present study, we focused on the characterization and impact of monocytes on brown adipose tissue (BAT) functions during tissue remodeling. Single-cell RNA sequencing analysis of BAT immune cells uncovered a large diversity in monocyte and macrophage populations. Fate-mapping experiments demonstrated that the BAT macrophage pool requires constant replenishment from monocytes. Using a genetic model of BAT expansion, we found that brown fat monocyte numbers were selectively increased in this scenario. This observation was confirmed using a CCR2-binding radiotracer and positron emission tomography. Importantly, in line with their tissue recruitment, blood monocyte counts were decreased while bone marrow hematopoiesis was not affected. Monocyte depletion prevented brown adipose tissue expansion and altered its architecture. Podoplanin engagement is strictly required for BAT expansion. Together, these data redefine the diversity of immune cells in the BAT and emphasize the role of monocyte recruitment for tissue remodeling.
Keyphrases
- adipose tissue
- dendritic cells
- peripheral blood
- positron emission tomography
- single cell
- insulin resistance
- bone marrow
- regulatory t cells
- immune response
- computed tomography
- high fat diet
- endothelial cells
- mesenchymal stem cells
- pet imaging
- pet ct
- genome wide
- social media
- machine learning
- minimally invasive
- fatty acid
- deep learning
- binding protein
- big data
- genetic diversity
- data analysis