IMMUNOHISTOCHEMICAL LOCALIZATION OF INTERLEUKIN-6-LIKE IMMUNOREACTIVITY TO PERIPHERAL NERVE-LIKE STRUCTURES IN NORMAL AND INFLAMED HUMAN SKIN

Interleukin-6-like (IL-6-like) immunoreactivity was sought in inflamed and normal human skin using the same immunohistochemical technique as for detection of neuropeptides, Such immunoreactivity was found in de rmal and in a few intraepidermal nerve-like fibres in biopsy specimens from inflamed skin from patients with positive epicutaneous patch-tes t reactions to nickel sulphate, and in skin specimens from patients wi th atopic dermatitis and prurigo nodularis. However, IL-6-like immunor eactivity was also found in nerve-like fibres in specimens from nonles ional skin, In skin from patients with positive epicutaneous patch-tes t reactions there was a statistically significantly (P < 0.01) higher number of IL-6-positive nerve fibres in the epidermis than in normal s kin, in contrast to the papillary dermis, in which no difference was f ound, Moreover, there were clusters of nerve-like fibres with IL-6-lik e immunoreactivity in the dermis of prurigo nodularis lesions, In thes e nerve-like fibres, the colocalization of the immunoreactivities for IL-6 and calcitonin gene-related peptide was indicated, Localization o f immunoreactivity to nerve-like structures surrounding the eccrine sw eat glands indicates that IL-6 is present in autonomic as well as in s ensory nerve fibres.