CCR9 and allergic disease: • Exacerbate inflammation in allergies (45, 56)• Th2 cytokine expression (45, 56)• ICOS-ICOSL dependent cytokine production (56)• Enriched transcripts of bZIP and NF-kB family (44)• CCR4, CCR9, and CXCR6 for migration and maintenance (41, 57)