Multiple AhR ligands can promote Treg development, leading to increased Treg numbers and improved outcomes in experimental autoimmune diseases.215 AhR activation enhances the expression of gut-homing molecules such as CD103, CCR6, Gpr15, and CCL20 in peripheral Tregs, facilitating their recruitment to the intestinal mucosa (Figure 4). This evidence concerns the gene AHR and autoimmune disease.