Langerhans cells in normal human skin capillaries

Rod-shaped bodies resembling birbeck granule-like structures in endothelial cells of dermal capillaries in generalized granuloma annulare

A previous study demonstrated that, in generalized granuloma annulare in the epidermis, the Langerhans' cell section area and the number of Langerhans' cell granules or Birbeck granules per cell section were increased, suggesting an active state of these Langerhans' cells. Reexamination by transmission electron microscopy of the same tissue, but in samples also containing dermal tissue, from the same subjects revealed endothelial cells with rod-shaped bodies resembling Birbeck granules or Birbeck granule-like structures. This finding has not been previously described in blood vessels of human skin and is described here.

Studies on human epidermal Langerhans cells III. Induction of T lymphocyte response to nickel sulphate in sensitized individuals

Human epidermis from nickel sensitive patients was separated from dermis by means of a suction blister device and dissociated with trypsin. The epidermal cell suspensions obtained contained 3--5% Langerhans cells as judged by immunofluorescence staining of the cells with a rabbit anti-DR antiserum. The epidermal cells were co-cultured with purified autologous T lymphocytes with or without nickel sulphate. A strong proliferative T lymphocyte response to nickel sulphate was obtained provided epidermal cells were also present. Pretreatment of the epidermal cells with anti-DR antiserum abolished or greatly reduced the response. These data indicate that epidermal cells are able to present nickel sulphate to T lymphocytes in an immunogenic way. Since the responsible cells were DR antigen positive, it is highly probable that the cells responsible for these functions are the Langerhans cells.