Macrophage markers 25F9 and 27E10 on human keratinocytes in normal and diseased skin

In the present study, an immunohistochemical analysis was made of the expression pattern of different macrophage markers such as 25F9, 27E10 and RM 3/1 on the surface of human keratinocytes (HK) in biopsies obtained from healthy volunteers and from patients with lichen planus, chronic cutaneous graft-versus-host reaction, mycosis fungoides, and purpura pigmentosa chronica. In biopsies from the healthy volunteers and from both clinically involved and uninvolved skin of the patients, the HK of the basal cell layer exhibited a specific peroxidase-positive reaction when the monoclonal antibody against 25F9 was used. Lesional HK from all patients studied displayed 25F9 and 27E10 in nearly the entire epidermis. The present findings provide further evidence that HK and macrophages share a number of common cell surface moieties.