[Cytotoxic effect on human keratinocytes caused by anti-Ro-(SS-A) antibodies and UVA in vitro].

It is supposed that anti-Ro(SS-A) antibodies play an important role in the development of photosensitive skin disease in subacute cutaneous lupus erythematosus and neonatal lupus erythematosus. The aim of the experiments was to demonstrate that anti-Ro(SS-A) antibodies and UVA-light cause a cytotoxic effect on human keratinocytes in vitro. Keratinocytes are irradiated with UVA-light in presence of serum containing anti-Ro(SS-A) antibodies (62 E, ELISA). After application of 20 J/cm2 UVA-light only 48.5% of the irradiated cells are still vital (standard trypan blue exclusions test). Examination by scanning electron microscopy shows plain depressions on the surface of the keratinocytes, which were irradiated in presence of anti-Ro(SS-A) antibodies.