Ribosomal Protein S6-Ps240 Is Expressed in Lesional Skin from Patients with Autoimmune Skin Blistering Diseases

BACKGROUND: The in situ signaling transduction within skin biopsies from patients affected by autoimmune skin blistering diseases is not well-characterized. AIM: In autoimmune skin blistering diseases, autoantibodies seem to trigger several intracellular signaling pathways and we investigated the presence of the phosphorylated form of ribosomal protein S6-pS240 within autoimmune skin blistering diseases biopsies. MATERIALS AND METHODS: We utilized immunohistochemistry to evaluate the presence of S6-pS240 in lesional skin biopsies of patients affected by autoimmune skin blistering diseases including patients with an endemic and nonendemic pemphigus foliaceus (non EPF), with bullous pemphigoid (BP), pemphigus vulgaris (PV), dermatitis herpetiformis (DH), and the respective controls. RESULTS: Most autoimmune bullous skin diseases biopsies stained positive for S6-pS240 around lesional blisters, including adjacent areas of the epidermis; and within upper dermal inflammatory infiltrates, and/or mesenchymal-endothelial cell junctions within the dermis. CONCLUSIONS: We document that S6-pS240 is expressed in lesional areas of skin biopsies from patients with autoimmune skin blistering diseases, as well as on eccrine glands and piloerector muscles. Thus, the role of this molecule in autoimmune skin blistering diseases warrants further study.