title: Preadipocyte conversion to macrophage. Evidence of plasticity.
abstract: Preadipocytes are present throughout adult life in adipose tissues and can proliferate and differentiate into mature adipocytes according to the energy balance. An increasing number of reports demonstrate that cells from adipose lineages (preadipocytes and adipocytes) and macrophages share numerous functional or antigenic properties. No large scale comparison reflecting the phenotype complexity has been performed between these different cell types until now. We used profiling analysis to define the common features shared by preadipocyte, adipocyte, and macrophage populations. Our analysis showed that the preadipocyte profile is surprisingly closer to the macrophage than to the adipocyte profile. From these data, we hypothesized that in a macrophage environment preadipocytes could effectively be converted into macrophages. We injected labeled stroma-vascular cells isolated from mouse white adipose tissue or 3T3-L1 preadipocyte cell line into the peritoneal cavity of nude mice and investigated changes in their phenotype. Preadipocytes rapidly and massively acquired high phagocytic activity and index. 60-70% of preadipocytes also expressed five macrophage-specific antigens: F4/80, Mac-1, CD80, CD86, and CD45. These values were similar to those observed for peritoneal macrophages. In vitro experiments showed that cell-to-cell contact between preadipocytes and peritoneal macrophages partially induced this preadipocyte phenotype conversion. Overall, these results suggest that preadipocyte and macrophage phenotypes are very similar and that preadipocytes have the potential to be very efficiently and rapidly converted into macrophages. This work emphasizes the great cellular plasticity of adipose precursors and reinforces the link between adipose tissue and innate immunity processes.
authors.affiliation: Unité Mixte de Recherche 5018 Université Paul Sabatier CNRS, IFR31, Bat L1, Centre Hospitalier Universitaire Rangueil, 31403 Toulouse, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Charrière
authors.forename: Béatrice
authors.initials: B
authors.lastname: Cousin
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Arnaud
authors.forename: Mireille
authors.initials: M
authors.lastname: André
authors.forename: Francis
authors.initials: F
authors.lastname: Bacou
authors.forename: Luc
authors.initials: L
authors.lastname: Penicaud
authors.forename: Louis
authors.initials: L
authors.lastname: Casteilla
mesh_terms: D016475:3T3 Cells; D017667:Adipocytes / Q000166:cytology*; D000465:Algorithms; D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis; D018122:B7-1 Antigen / Q000096:biosynthesis; D051940:B7-2 Antigen; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D019070:Cell Lineage; D018920:Coculture Techniques; D018076:DNA, Complementary / Q000378:metabolism; D007150:Immunohistochemistry; D017493:Leukocyte Common Antigens / Q000096:biosynthesis; D008264:Macrophages / Q000166:cytology*; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D010586:Phagocytes / Q000166:cytology / Q000378:metabolism; D010587:Phagocytosis; D010641:Phenotype; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; C497965:Cd86 protein, mouse; D018076:DNA, Complementary; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D017493:Leukocyte Common Antigens