Significance of the Ro antigen system.

Knowledge about antibodies to the Ro/SSA and La/SSB antigens has expanded greatly. Recognition of these antibodies was probably achieved 25 years ago but their macromolecular structure, clinical associations, and genetic relationships have come to light only in the past 7 years. It seems clear that these antibodies have a special place in the nosology of SLE and SS and that in certain instances (e.g., neonatal LE) the antibodies play a direct pathogenic role, while in other circumstances (e.g., vasculitis, nephritis, SS) tissue damage might result from immune complex deposition on vascular structures. Certainly, the latter problems will be active areas of investigation in the coming years. If the pace of recent progress continues, many of the questions raised in this review should soon have clear answers.