CCR4(+) memory CD4(+) T lymphocytes are increased in peripheral blood and lesional skin from patients with atopic dermatitis

Background: Recent studies have reported that T(H)1 and T(H)2 cells express CXCR3 and CCR4, respectively. Objective: Our goal was to assess the association of CCR4 and CXCR3 express ion with T(H)2 and T(H)1 cells and association of CCR4 and CXCR3 expression with inflammation in patients with atopic dermatitis (AD). Methods: Intracellular cytokine production and chemokine receptor expressio n in blood T cells were examined by flow cytometry. Immunohistochemical exp ression of chemokine receptors was also investigated in chronically lesiona l skin. Results: CCR4(+) and CXCR3(+) CD4(+) T cells predominantly produced IL-4 an d IFN-gamma, respectively. Although the frequency of CXCR3(+) cells among C D4(+) CD45RO(+) T cells was similar for patients with AD (n = 29) and healt hy control subjects (n = 19), patients with severe AD (n = 14) had a reduce d frequency of CXCR3(+) cells. In contrast, the frequency of CCR4(+) cells and the CCR4/CXCR3 ratio were higher in patients with AD (n = 22) than heal thy control subjects (n = 16) and correlated with disease severity of AD. T he frequency of CCR4(+) cells correlated positively with eosinophil numbers and serum IgE levels, whereas the frequency of CXCR3+ cells correlated inv ersely with eosinophil numbers. The frequency of CCR4+ or CXCR3(+) cells wa s similar in patients with psoriasis (n = 6) and healthy control subjects. Immunohistochemical analysis showed that the frequency of CCR4(+) cells amo ng CD4(+) T cells in chronically lesional skin of patients with AD (n = 9) was higher than that of patients with psoriasis (n = 4). Conclusion: Our data suggest the association of CCR4(+) expression with T(H )2 cells, the predominance of CCR4(+) cells in blood from patients with AD, and an important role of CCR4 in the migration of T(H)2 cells from blood i nto AD lesional skin.