Perforin expression is upregulated in the epidermis of psoriatic lesions

There are currently very few data regarding the role of cell-mediated cytotoxicity in psoriasis. Both cytotoxic T lymphocytes and natural killer (NK) cells mediate cytotoxicity reactions, mainly by two distinct pathways, the perforin/granzyme and the Fas/Fas ligand pathway.

To study the expression and distribution of perforin, T- and NK-cell subsets in psoriatic lesional and nonlesional skin.

Skin biopsy specimens from both lesional and nonlesional skin of 11 patients with chronic plaque psoriasis and eight healthy controls were analysed by immunohistochemistry.

We found a significant increase in CD4+ and CD8+ cells in psoriatic lesions compared with nonlesional and healthy skin. The expression of CD16+ NK cells was significantly lower in lesions compared with healthy skin. Perforin expression was significantly enhanced in the epidermis of psoriatic lesions.

Perforin expression is upregulated in the epidermis of psoriatic lesions, suggesting a potential role for perforin in the creation of the psoriatic plaque.