CCL22 Gene - C-C Motif Chemokine Ligand 22 | Function, Expression & Disease

CCL22 (C-C Motif Chemokine Ligand 22) is a chemokine gene that encodes a small cytokine belonging to the CC chemokine family. The encoded protein, also known as Macrophage-Derived Chemokine (MDC), is secreted by dendritic cells, macrophages, and other immune cells. It binds to the chemokine receptor CCR4, playing a critical role in the recruitment of regulatory T cells (Tregs), Th2 cells, and other leukocytes to sites of inflammation and tumors. CCL22 is involved in immune homeostasis, allergic responses, and cancer immune evasion.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Chemokine signaling pathway (KEGG: hsa04062)

• Cytokine-cytokine receptor interaction (KEGG: hsa04060)

• T cell receptor signaling pathway (KEGG: hsa04660)

CCL22 is a 93-amino acid secreted chemokine (precursor 93 aa, mature 69 aa) with a typical CC chemokine structure containing four conserved cysteine residues. It is produced primarily by macrophages, dendritic cells, and certain tumor cells. The protein binds specifically to CCR4, a G protein-coupled receptor expressed on Th2 cells, Tregs, and some cancer cells. CCL22 plays a dual role in immune regulation: it mediates allergic inflammation by recruiting Th2 cells, and it promotes immune evasion in cancer by attracting Tregs into the tumor microenvironment. Elevated CCL22 levels are associated with poor prognosis in several cancers.