Granulysin-bearing cells in the skin lesions of acute graft-versus-host disease: Possible mechanisms for hypohidrosis in graft-versus-host disease

Graft-versus-host disease (GVHD) is an important complication of bone marrow transplantation and is known to induce sweat gland abnormalities. We employed immunohistochemical staining for granulysin, dermcidin as well as IL-17 and Foxp3 in the lesional skin of 7 patients with acute GVHD. Granulysin-bearing cells were distributed in the epidermis, basal membrane zone of the dermis, and superficial perivascular lesion of the dermis. Interestingly, granulysin-bearing cells were also detected around the secretory portion of the eccrine glands, which might be related to the downregulation of the expression of dermcidin on the secretory portion of the eccrine glands. Differing from a mouse model, in human acute GVHD, IL-17-producing cells and Foxp3⁺ cells were not prominent. Our present observation sheds light on the contribution of granulysin-bearing cells to the decrease of the sweat in patients with acute GVHD. Though we did not assess the function of these infiltrating lymphocytes directly, further analysis of the mechanism of this phenomenon would offer fundamental insight into the establishment of acute GVHD.