Table 2.

Direct Effects of AhR ligands on T cells in experimental asthma models.

Experimental Model	AhR Ligand	T Cell Response	Ref
Non-eosinophilic asthma model	2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)	Treg induction and inhibition of Th17 activation.	[21]
Ozone induced airway inflammation	Lipoxin A4	Inhibition of Th17/22 response	[20]
Ovalbumin-induced allergic asthma	Indoxyl 3-sulfate (I3S)	Inhibition of Th2 differentiation	[14]
	4-nonylphenol	Increased secretion of Th2 cytokines	[28,29]
	Indeno[1,2,3-cd]pyrene
House Dust Mite-induced allergic asthma	Benzo(a)pyrene (B(a)P) or particle matter 2.5µm (PM2.5)	Increased secretion of Th2 but not Th1 or Th17 cytokines	[26,32]
Cockroach-sensitized mouse model	PM2.5	Increased Th17 cells and decreased Foxp3 regulatory T cells	[35]