CCL26 (C-C motif chemokine ligand 26) is a chemotactic cytokine that functions primarily as a chemoattractant for eosinophils and basophils through binding to the C-C chemokine receptor CCR3, triggering calcium mobilization in target cells 123. Additionally, CCL26 can bind to CX3C chemokine receptor CX3CR1 to induce cell chemotaxis 4. The protein plays a crucial role in type 2 inflammatory responses, with elevated expression observed in atopic dermatitis lesions as part of the disease's characteristic inflammatory profile 5. CCL26 expression is regulated by IL-4 and IL-13 signaling pathways, as evidenced by its downregulation following dupilumab treatment (an IL-4 receptor α antagonist) in atopic dermatitis patients 56. The chemokine is also involved in macrophage polarization, being transcribed by M(IL-4) polarized macrophages 7. In the tumor microenvironment, CCL26 participates in crosstalk between tumor cells and tumor-associated macrophages through CX3CR1 signaling 8. Clinically, CCL26 serves as a biomarker for monitoring type 2 inflammation and treatment response across various atopic diseases 910.