title: In situ localization of interleukin-6 in normal skin and atrophic cutaneous disease.
abstract: Interleukin-6 (IL-6) is a multifunctional cytokine that participates in the inflammatory and immune responses. In human skin, keratinocytes produces IL-6, although the in vivo role of this cytokine is unknown. In the present study we investigated the in situ localization of IL-6 in normal epidermis (n = 10) and in a group of skin diseases characterized by epidermal atrophy. Formalin-fixed paraffin-embedded skin biopsies from patients with clinical and histopathological features consistent with localized scleroderma (n = 10), systemic scleroderma (n = 5), lichen sclerosus et atrophicus (n = 9) and balanitis xerotica obliterans (n = 7) were tested using polyclonal antibodies and avidin-biotin-peroxidase immunostaining. We demonstrated the presence of IL-6 in normal epidermis and in atrophic skin diseases. In normal skin there was moderate intercellular and intracellular reactivity detected using a high antibody concentration. In specimens with epidermal atrophy we detected intense cytoplasmic and intercellular immunostaining using a lower antibody concentration. The immunoreactivity was independent of the epidermal thickness. Plasma IL-6, measured by radioimmunoassay, was not elevated in plasma from patients with localized or systemic scleroderma. Increased IL-6 in the epidermis of selected skin diseases suggests that IL-6 may be related to the pathophysiology of dermatologic diseases characterized by epidermal atrophy.
authors.affiliation: Department of Dermatology, New England Medical Center Hospital, Tufts University School of Medicine, Boston, Mass.
authors.forename: L I
authors.initials: LI
authors.lastname: Romero
authors.forename: S H
authors.initials: SH
authors.lastname: Pincus
mesh_terms: D000918:Antibody Specificity; D001284:Atrophy; D001323:Autoantibodies / Q000032:analysis; D001446:Balanitis / Q000276:immunology; D004817:Epidermis / Q000276:immunology / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D015850:Interleukin-6 / Q000032:analysis*; D017512:Lichenoid Eruptions / Q000276:immunology; D008297:Male; D011863:Radioimmunoassay; D012594:Scleroderma, Localized / Q000276:immunology; D012595:Scleroderma, Systemic / Q000276:immunology; D012867:Skin / Q000276:immunology*; D012871:Skin Diseases / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D015850:Interleukin-6