Identification and characterization of novel dermal Thy-1 antigen-bearing dendritic cells in murine skin

Using immunofluorescence on dermal sheets of mouse ear, we identified novel Thy-1⁺ dermal dendritic cells in murine skin. These cells are resistant to topical corticosteroid treatment. The number of these dermal Thy-1⁺ dendritic cells is not altered with aging of the mice or with 3 d of culture. Dermal Thy-1⁺ dendritic cells have melanosomes in their cytoplasm; hence, phagocytic activity is likely to be present. Double immunofluorescence revealed that most of these dermal Thy-1⁺ dendritic cells express CD45. Furthermore, conventional immunofluorescence and confocal laser scanning microscopic findings showed that most of these Thy-1⁺ dermal dendritic cells express γδ and Vγ₃ T-cell receptors. The relationship between these dermal Thy-1⁺ dendritic cells and dendritic epidermal T cells is discussed.