Thymic Epithelial Cell Development and Its Dysfunction in Human Diseases

Table 2

Molecules involved in TEC development.

Family	Molecule	Receptor	Source	Function	References
TNF	RANKL	RANK	Embryonic: LTi, DETC	Thymic medulla formation	[17, 18]
			Postnatal: positively selected thymocytes	mTEC development	[19, 20]
	CD40L	CD40	Positively selected thymocytes	mTEC development	[19–22]
				mTEC proliferation	[19–22]
	LT𝛼1𝛽2, LIGHT	LT𝛽R	Positively selected thymocytes	mTEC development	[23–25]
				Promote RANK signals	[26]
				mTEC terminal differentiation	[27]
FGFs	FGF8		Pharyngeal region	Thymopoiesis	[28]
	FGF10	FGFR2IIIb	Positively selected thymocytes	mTEC proliferation	[29]
	FGF7	FGFR2IIIb	Positively selected thymocytes	mTEC and thymocyte Proliferation	[30, 31]
				Protect thymus damage	[32–34]
				Enhance thymopoiesis	[35, 36]
Wnt	wnt4	Frizzled	TECs, fibroblast	Regulate Foxn1 expression	[37]
				Thymopoiesis	[38–40]
Notch	Jagged, Delta	Notch	Thymocyte progenitor	TEC survival and development	[41–43]

DETC: invariant V𝛾5⁺ dendritic epidermal T cells; RA: retinoic acid.