CCL22 and vitiligo: Studies have shown that various cytokines including interferon-γ (IFN-γ) [3], [12], tumor necrosis factor α (TNFα) [13], [14] and chemokine (C-C motif) ligand 22 (CCL22) [15] are differentially expressed in the lesional skin and serum of vitiligo patients and health controls, indicating their roles in vitiligo.