Is CCR7 a potential target for biologic therapy in psoriasis?: Increased expression of CCR7 in psoriasis vulgaris

Abstract

Activated T cells present in psoriatic plaques play a key role in the pathogenesis of psoriasis. CCR7 on T cells plays a crucial role in native immune response and formation of secondary lymphoid organ. To determine whether differential expression and functions of the CCR7 occur in psoriasis patients in China, we examined CCR7 on T cells from normal and psoriasis subjects. Skin specimens and T cells from 33 patients and 22 healthy controls were analyzed by immunohistology, flow cytometry, and RT-PCR. Patients with psoriasis had a skewed distribution of T lymphocytes, with an increased level of CCR7+ T lymphocytes compared to healthy controls (P<0.01) By flow cytometry, it was found that CCR7 was selectively, frequently, and functionally expressed on CD4+ (20.5+/-6.8%)but not on CD8+ (9.5+/-3.4%) T cells from patients with psoriasis, whereas this phenomenon was not seen in normal subjects. Through RT-PCR it was also found that CCR7 was highly expressed on T cells in patients with psoriasis than in healthy controls in the level of gene. Patients with psoriasis had a skewed distribution of T lymphocytes, with an increased level of CCR7+ T lymphocytes compared to healthy controls. CD4+ CCR7+ T cells had abnormal expression, which might induce protraction and persistence of psoriasis.