Murine CCL22 is a small cytokine protein that induces the migration of CCR4+ Th2 cells, Tregs, dendritic cells, and NK cells. CCL22 gets induced by LPS and CD40 antibody in macrophages, and is upregulated by Th2 cytokines (IL-4 and IL-5) and downregulated by Th1 cytokines (IFNγ) and is able to carry out its functions primarily by interacting with its chemokine receptor, CCR4.