Abstract: Objective: To detect the level of CD103+T lymphocytes in psoriatic lesions and to determine the relationship with the severity of psoriasis. Methods: CD103+T lymphocytes in dermis?and?epidermis of the lesions and non-lesional skin from 29 patients with psoriasis and skin from 6 healthy controls were detected by immunohistochemical staining. Results：CD103+T lymphocytes mainly distributed in dermis. The mean percentage of CD103+T lymphocytes in lesions, non-lesional skin and normal skin was (26.06±11.72%), (12.82±4.50%) and (7.47±1.30%) and there?were significant differences among the groups (P<0.05). There was a positive correlation between the level of CD103+T lymphocytes and the PASI score (P<0.05). Conclusion：CD103+T lymphocytes in the dermis may associate with the occurrence and severity of psoriasis.

Key words: psoriasis, CD103+T lymphocytes, immunohistochemical staining