Table 2.

HSC niches during development

Development Stage	Niche Cells	Hematopoietic Supporting Factors
AGM	Mesenchymal Cells Mφ	Notch1 and Wnt, IFN-γ, IL-3, TNF, IFNα and IFNβ
FL	Endothelial cells[121, 217] Desmin+ Stellate Cells[114, 121] p75NTR+ Stellate Cells[110] Dlk1+ or CD3+DLK1+SCF+ Hepatocyte Progenitors[105, 109, 111, 112, 120, 121] Lyve-1+ Sinusoidal Network Nestin+NG2+ Pericytes of Portal vessels[117] Neutrophils	CXCL12, KITL, WNT5A IL-3, IL-6, CSFs and EPO CSF1, IGF2, THCO, KITL, EPO, IGF1, IL-1, FLT3 Ligand and Oncostatin M KITL, IGF2, Angpt2, Angpt3, THPO, CXCL12, α-fetoprotein, bile acids, VCAM1, Fibronectin1, Vitronectin1, Laminin-b1 and Laminin-c1, DHA Undefined factor(s) maintain slow cycling state of HSCs KITL, Angptl2, and IGF2 MMP9 for HSCs release from FL
Fetal BM	Osterix+ Stromal Progenitors[128–130]	CXCL12, Osteopontin, VEGF, Slit, and SCF, Collagen, N-cadherin, VCAM, Selectins, Fibronectin, Integrins