Immunohistochemical study of dermal cell popoulation in psoriatic skin.

As demonstrated by means of an immunoperoxidase technique, the great majority of the infiltrating mononuclear cells located in the superficial and middle dermis of psoriatic skin consisted of T-lymphocytes. On the contrary, immunoglobulin bearing cells, investigated by means of both immunoperoxidase and immunofluorescence methods, were scarce; IgA and IgG cells were predominant, whilst IgM cells were scarcely represented. Macrophages and monocytic cells were observed in the superficial dermis by means of the alpha-naphtyl-acetate-esterase method, in frozen sections. The role of the above mentioned cells and the significance of their reciprocal relationships still remains in discussion.