A 10-year-old Japanese male with multiple blister formation and palpable purpura in the course of anaphylactoid purpura is described. Histologically, the lesions showed leukocytoclastic vasculitis in the upper dermis with subepidermal clefts. Blister fluid showed matrix metalloproteinase (MMP) 2 and MMP-9 gelatinolytic activities using zymography. These enzymatic reactions, especially that involving MMP-9 derived from polymorphonuclear leukocytes, might play an important role in the pathophysiology of this condition.
Two cases are reported of cutaneous anaplastic large-cell lymphoma with the suppressor/cytotoxic (CD8) phenotype. In both cases there was a solitary skin tumour in which there was a dense infiltrate with large irregularly shaped cells which on immunophenotyping expressed CD8. DNA hybridization analysis showed rearrangements of the T-cell-receptor gene in both cases.
We have examined the character and carcinogenic properties of the normal-appearing epidermis overlying basal cell carcinomas by immunohistochemical methods, employing a series of monoclonal antibodies. The labelling index was significantly increased in the atrophic epidermis overlying basal cell carcinomas (solid type, n = 20), compared with the epidermis overlying or adjacent to squamous cell carcinoma (n = 20), keratoacanthoma (n = 10), dermatofibroma (n = 10), neurofibroma (n = 10), soft fibroma (n = 10), pyogenic granuloma (n = 10) and cutaneous leiomyoma (n = 5). Cells which expressed epidermal growth factor (EGF) receptor were detected in all layers of the epidermis over the basal cell carcinomas, but not the other tumours. Basement membrane-related antigens, including bullous pemphigoid antigen and GB3 antigen, were decreased in the epidermis. AE1, the monoclonal antibody against basal cell keratin, reacted with the uppermost layers of the normal-appearing epidermis overlying the basal cell carcinomas. ICAM-1 expression was very weak in the overlying epidermis. The dermis subjacent to the proliferating epidermis showed staining for transforming growth factor-alpha (TGF-alpha), strong positive PECAM-1 staining of endothelium, and numerous HLA-DR-positive cells. From these results, we suggest that the proliferative activity in the epidermis overlying basal cell carcinomas is not a state induced by the dermal infiltrate, but represents carcinogenic activity of the epidermis.
Background: The formation of lacunae and acantholysis as well as dyskeratosis are characteristic features of Hailey-Hailey disease (HHD) and Darier’s disease (DD). Matrix metalloproteinases (MMPs) and their inhibitors like tissue inhibitors of metalloproteinases (TIMPs) have been thought to play major roles in the tissue metabolism. Objective: The aim of this study was to investigate the role of MMP-9 and TIMP-1 in HHD and DD Methods: We examined localizations of these two molecules by immunostaining using specific monoclonal antibodies. Results: MMP-9 was positively stained in dyskeratotic or detaching cells around lacunae in HHD and DD. TIMP-1 showed a positive staining pattern throughout the epidermis. Conclusion: MMP-9 might be involved in the pathophysiological process of HHD and DD in the presence of TIMP-1.
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