Simon M Jr, Heese A, Götz A.
DOI: 10.2340/000155556910110

We studied the cell infiltrates and antigenic characteristics of keratinocytes in biopsies from purpura pigmentosa chronica (PPC), with eleven monoclonal antibodies against several cell surface markers of effector and/or accessory cells of the immune system and compared the reactivity patterns with those in biopsies from uninvolved skin. Immunohistochemical staining revealed a predominance of activated helper T lymphocytes in the cutaneous inflammatory infiltrate. In contrast to uninvolved skin, lesional keratinocytes were found to express HLA-DR, OKM5, Leu-8 and Leu-11b (CD16) antigens in all biopsies from the involved skin. We demonstrate here for the first time the in vivo expression of several effector and/or accessory cell markers on lesional keratinocytes and infiltrate cells in PPC.