Abstract
Background: Skin lesions from graft-versus-host disease (GVHD) show histological features of epidermal cell death with lymphocyte infiltration. Perforin and granzyme B are involved in the process of apoptosis induced by cytotoxic T lymphocytes (CTL). Objective: To elucidate the role of CTL in the mechanism of epidermal injury in GVHD. Methods: We studied immunohistochemical staining for granzyme B and perforin in the skin lesions of 8 patients who developed GVHD after bone marrow transplantation. Results: Granzyme-B-positive lymphocytes were CD8 positive and were observed in the epidermis of 3 out of 6 specimens in acute GVHD, and of 5 specimens of chronic GVHD except for 1 sclerotic type in which it was negative. Perforin-positive lymphocytes were observed in the epidermis of the specimens from 1 acute and 1 chronic GVHD. Conclusions: Granzyme B derived from CTL may be involved in the mechanisms of epidermal injury in GVHD.