Inflammatory cell types in normal human epidermis--an immunohistochemical and morphometric study.

Inflammatory cells in 15 specimens of normal human epidermis were selectively stained by a monoclonal antibody immunoperoxidase technique. The quantitative assessment using an interactive image analysis system revealed OKT 11 positive cells (T lymphocytes) and Leu 2a positive cells (suppressor/cytotoxic cells). As there was no significant difference in the distribution of these markers, helper/inducer cells obviously are not present in considerable amounts. OKM 5 positive cells outnumbered OKM 1 positive cells, indicating the presence of a OKM 5+, OKM 1-macrophage subset. The epidermal dendritic cells clearly showed a striking heterogeneity regarding the expression of HLA-DR (62% of OKT 6-positive cells) and Leu 3a (47%), suggesting the existence of immunologically distinct subsets of human epidermal dendritic cells.