Table 1.

Summary of Wnt Ligands and Their Functions^a

Wnt ligand	Cellular sources	Target cells	Function
Wnt3a	Unknown	Tregs Cord blood cells CD8 T cells	Inhibition of suppressor function [76] (m,h) Enhancing human Th2 cell differentiation [64] (h) Inhibits proliferation/effector differentiation [58] (m)
	Stromal cells	HSC cells	Promotes HSC self-renewal/progenitor cell differentiation [83] (m)
	Macrophages	HPCs Thymocytes	Normal T cell development [9] (m) Transition from HPCs to hepatocytes [38] (m,h)
Wnt5a	Melanoma cells	DCs (m)	Fatty acid oxidation to induce tolerogenic DCs [24] (m)
	Macrophages	Kidney cells	Wound healing [37] (m)
	DCs	CD4 T cells T cells	Enhances IL-2 and IFN-γ secretion [29] (h)
	Thymic stromal epithelium	Thymocytes	Sensitizes T cells to CXCL12-mediated migration (h,m) [71]
	Follicular DCs	GC B cells	Inhibits apoptosis of αβ TcR+ thymocytes [9] (m) Protects GC B cells from apoptosis [28] (h)
Wnt 2b	Macrophages	Unknown	Wound healing in the TNBS colitis model [6] (m)
Wnt 7b	Myeloid cells	Unknown	Angiogenic switch/supports macrophage-mediated lung metastasis [39] (m,h)
	Macrophages	Unknown	Metabolic sepsis, cancer, obesity, atherosclerosis
	Macrophages	Unknown	Induce immunosuppressive macrophages in sepsis and breast cancer [40] (m,h) Required for kidney injury repair [37] (m)
Wnt 10a	Macrophages	Unknown	Required for kidney injury repair [37] (m)
Wnt 10b	Unknown	CD4 T cells	Inhibiting Th2-mediated asthma [65] (m)
DKK-1	Platelets	T cells	Th2 cell differentiation [5] (h,m)
	Cancer cells	NK cells	Inducing senescence of cancer cells to evade NK cell-mediated cytolysis [4] (m)
	Myeloid cells	Unknown	Promoting cancer inflammation [87] (m)
	Osterix-1+ cells	HSCs	Promoting HSC compartment repopulation [85] (m)
	Tregs	Effector CD4 T cells	Preventing T cell-mediated colitis [92] (m)
DKK-2	Unknown	CD8 T cells/NK cells	Inhibition of cytotoxic activity [89] (m)
DKK-3	Tubular epithelial cells	Unknown	Promoting kidney disease with more Th1 cell differentiation in Dkk3-deficient condition [90] (m)
	CD8 T cells	Unknown	CD8 T cell-mediated tolerance induction [91] (m)
sFRP5	Adipocytes	Unknown	Anti-inflammatory role in obesity-related inflammation [110] (m)
	Unknown	B cells	Decreases B cell progenitor development [106] (m)
sFRP1	Synovial fluid	CD4+ T cells	Promotes Th17 cells [112] (h)

^ah, human; m, mouse.