. Author manuscript; available in PMC: 2024 Mar 7.

Published in final edited form as: Cell Metab. 2023 Mar 7;35(3):386–413. doi: 10.1016/j.cmet.2023.02.002

Table 2.

Adipose stromal subpopulations identified by single-cell transcriptomics

Subtypes	Depot	Published nomenclature	Signature transcripts	Functional properties	Human correlate (blank if unknown)	Published isolation strategies (CD45− CD31− = Lin−)	Tissue localization
Preadipocytes (proposed nomenclature)	iWAT	• P2¹⁶⁷ • Group2/committed preadipocytes/ICAM1+ cells¹⁶⁰ • ASC1¹⁶⁴ • DPP4− PDGFRβ+ cells²³ • CD81^High APCs¹⁶⁸ • IS3¹⁶⁶	Pparg Icam1 Pref1 Col4a2	committed preadipocytes	yes	Lin− ICAM1+ CD142− (Merrick et al.¹⁶⁰) Lin− PDGFRβ+ DPP4−(Shao et al.¹⁶²)	perivascular
	eWAT	• APCs⁷⁴ • ASC1¹⁶¹ • VmSC4/5¹⁶⁵ • FAP1/2¹²³ • ES2/3¹⁶⁶ • mASPC1/5¹²¹	Pparg Cd36 Fabp4 Cd34 ^Lo	• committed preadipocytes	yes	Lin− PDGFRβ+ LY6C− CD9− (Hepler et al.¹⁶³)	perivascular
FAPs (proposed nomenclature)	iWAT	• P1¹⁶⁷ • Group1/interstitial progenitor cells/DPP4+ cells¹⁶⁰ • ASC2¹⁶⁴ • DPP4+ PDGFRβ+ cells²³ • CD81^Low cell¹⁶⁸ • IS1¹⁶⁶	Dpp4 Wnt2 Anxa3 Pi16 Cd55	• multi-mesenchymal lineage potential in vitro • adipogenic in vivo; give rise to preadipocytes • cold responsive; secrete IL-33	yes	Lin− DPP4+ CD142− (Merrick et al.¹⁶⁰) Lin− PDGFRβ+ DPP4+ (Shao et al.¹⁶²) Lin− SCA1+ CD55+ (Schwalie et al.¹⁶⁷)	reticular interstitium proximity to blood vessels
	eWAT	• FIPs⁷⁴ • ASC2¹⁶¹ • VmSC1/2/3¹⁶⁵ • FAP3/4¹²³ • CD34^High cells¹⁶⁹ • ES1¹⁶⁶ • mASPC2/3¹²¹	Dpp4 Ly6c Fn1 Pi16 Il33 CD55 Cd34 ^High	• resistant to adipogenesis (adulthood) • anti-adipogenic (adulthood) • robust proinflammatory response; promote macrophage accrual • robust collagen deposition • secrete IL-33; promote Treg accrual	yes	Lin− PDGFRβ+ LY6C+ (Hepler et al.¹⁶³)	within tissue mesothelium proximity to blood vessels
Additional stromal subpopulations	iWAT	• Aregs¹⁶⁰ • Group3¹⁶⁰	Cd142, Clec11a Fmo2	• secrete RSPO2, inhibit preadipocyte commitment (adulthood)	yes	Aregs: Lin− SCA1+ CD142++ (Dong et al.¹⁷⁰)	–
Additional stromal subpopulations	iWAT	ARCs¹⁷¹	CD36, Lgals3 Ccl6	• secrete CCL6; inhibit AP differentiation and proliferation	yes	Lin− CD36+ Lgals3+	–
Brown adipocyte precursors	Interscapular BAT	ASC1¹⁷²	Col5a3 Cxcl14 Bmper	• ASC1: upregulation of proliferation and adipogenesis gene profiles upon cold exposure	–		mixed location: tissue fascia; interstitial; surrounding vessels; contact F4/80+ immune cells
		ASC2¹⁷²	DPP4 Pi16
		ASC3¹⁷²	Clec11a Gdf10
		Trpv1+ VSM-APCs¹⁷³	Trpv1 Sca1− Cd81−	• proliferate upon cold exposure • give rise to brown and white adipocytes	yes	Trpv1^Cre reporter mice	vascular smooth muscle cells
	perivascular BAT (PVAT)	intermediate cells¹⁷⁴	Vipr2 Gli1	• resistant to adipogenesis	–	PDGFRa+ CD200+	in between the vascular SMCs and adventitial progenitors
	perivascular BAT (PVAT)	SMC-2 (adult)¹⁷⁴	Pparg Trpv1 Myh11	• adipogenesis	yes	MCAM+ CD200−	aortic adventitia/vascular smooth muscle cells
Skeletal bone marrow APCs	bone marrow adipose tissue	MALPs¹⁷⁵	Adipoq Pparg Vegfa	• committed preadipocytes lacking Plin1 expression and lipid droplets • expressed RANKL and promotes osteoclastogenesis	–	–	bone marrow pericytes
Skeletal bone marrow APCs	bone marrow adipose tissue	EMPs¹⁷⁵	Ly6a Cd34 Thy1 Mfap5 Clec3b	• number reduces with age • prefer adipogenesis to osteogenesis with age	–	–	–

Single-cell/nuclei RNA sequencing identified adipose stromal cell populations in WAT and BAT depots. Proposed nomenclature, published nomenclature, defining transcripts, proposed presence in human adipose tissue, experimentally validated isolation strategy, and tissue localization are indicated.