In situ production of innate immune cells in murine white adipose tissue.
White adipose tissue (WAT) is the focus of new interest because of the presence of an abundant and complex immune cell population that is involved in key pathologies such as metabolic syndrome. Based on in vivo reconstitution assays, it is thought that these immune cells are derived from the bone marrow (BM). However, previous studies have shown that WAT exhibits specific hematopoietic activity exerted by an unknown subpopulation of cells. In the present study, we prospectively isolated a peculiar hematopoietic stem/progenitor cell population from murine WAT. The cells are phenotypically similar to BM hematopoietic stem cells and are able to differentiate into both myeloid and lymphoid lineages in vitro. In competitive repopulation assays in vivo, they reconstituted the innate immune compartment in WAT preferentially and more efficiently than BM cells, but did not reconstitute hematopoietic organs. They were also able to give rise to multilineage engraftment in both secondary recipients and in utero transplantation. Therefore, we propose that WAT hematopoietic cells constitute a population of immature cells that are able to renew innate immune cell populations. Considering the amount of WAT in adults, our results suggest that WAT hematopoietic activity controls WAT inflammatory processes and also supports innate immune responses in other organs.
Centre National de la Recherche Scientifique 5273, Unité Mixte de Recherche STROMA Lab, Toulouse, France.
Sandrine
S
Poglio
Fabienne
F
De Toni
Daniel
D
Lewandowski
Adeline
A
Minot
Emmanuelle
E
Arnaud
Vilma
V
Barroca
Patrick
P
Laharrague
Louis
L
Casteilla
Béatrice
B
Cousin
D052436:Adipose Tissue, White / Q000166:cytology* / Q000276:immunology* / Q000637:transplantation; D000818:Animals; D000950:Antigens, Ly / Q000032:analysis; D002454:Cell Differentiation; D005260:Female; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D007113:Immunity, Innate; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology; D008214:Lymphocytes / Q000166:cytology* / Q000276:immunology; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D022423:Myeloid Cells / Q000166:cytology* / Q000276:immunology; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis
D000950:Antigens, Ly; C074650:Ly6a protein, mouse; D008565:Membrane Proteins; D019009:Proto-Oncogene Proteins c-kit