Alexa Fluor(R) 647 anti-human CD194 (CCR4)

CCR4 is a CC chemokine receptor, and it was clone from a human basophylic cell line KU-812 in 1995. (1). CCR4 binds CCL17 and CCL22 and is expressed on stimulated and unstimulated T, and B cells, basophils, monocytes, and NK cells. Human Th2 cells are characterized by the expression of CCR4 and CCR8 (2), and these receptors are regulated differently during Th2 development (3). Human peripheral blood Tregs can be divided into two distinct populations based on the expression of CCR4. Freshly isolated Tregs express CCR4 and presumably represent memory-type Tregs, and CCR4(-) Tregs require anti-CD3 Ab-mediated activation to acquire a regulatory activity. Depletion of CCR4(+) T cells leads to Th1-type polarization of CD4(+) T cells and augmentation of CD8(+) T cell responses to tumor Ags (4). CCR4 and its ligands are important for the recruitment of memory T cells into the skin in various cutaneous immune diseases (5).