Figure 2. Lateral association of CD69 with the amino acid transporter LAT1-CD98 complex regulates TH1/TH17/Treg balance.
Cartoon depicts the lateral interactions of CD69 with the LAT1-CD98 amino acid transporter complex. CD69 increase Trp transport through LAT1-CD98 and favors AHR activation through binding of the Trp-derived FICZ ligand. Activation of AHR-transcriptional activity favors IL-22 secretion. Amino acid uptake through CD69/LAT1-CD98 complex also favors mTOR activation, which promotes TH1 and TH17 development and prevents Treg-cell differentiation. mTOR also controls HIF-1α, which negatively regulates Treg-cell function by promoting Foxp3 degradation. AHR expression attenuates HIF-1α-mediated effects and modulates the TH-phenotype of effector T cells.