A monoclonal Ro‐antibody and the serum of a Ro‐positive patient with subacute cutaneous lupus erythematosus (SCLE) react with basal layers of human epidermis

Publisher Website
Google Scholar
Abstract
Skin lesions, especially at areas exposed to sunlight, prove to be a major form of manifestation of diseases related to Ro-antibodies and neonatal-,''ANA-negative-'', and cutaneous types of lupus erythematosus. A monoclonal Ro-antibody established by our group reacts with a 60 kD polypeptide in extracts from human spleen, whereas in extracts from human epidermis the monoclonal Ro-antibody and a purified Ro-antibody from a monospecific serum of a patient with subacute cutaneous lupus erythematosus reacted with a 60 kD and a 48 kD protein. Performing immunofluorescence microscopy on HEp2-cells both antibodies showed a nuclear speckled staining pattern and a reaction with cytokeratin filaments. On skin biopsies obtained from the patient, predominantly the basal layers of the proliferative stratum germinativum demonstrated a high rate of immunofluorescence; antigen-expression seems to depend on sunlight exposure. From these data we assume that, especially in subacute cutaneous lupus erythematosus, cross-reaction of the Ro-antibody with one of the lower molecular keratins happens in that area of human epidermis which histologically shows cellular destruction.