Profiles of Autoantibodies Against Ro/SSA and La/SSB Antigens in Mothers of Infants with Neonatal Lupus Erythematosus

Abstract

The serum samples of 18 mothers of infants with neonatal lupus erythematosus (NLE) observed at Nara Medical University and its associated hospitals over a period of 24 (1977–2000) years were analysed for anti-Ro/SSA and La/SSB antibody profiles. The antibodies were examined by double immunodiffusion (DID), using swine spleen extracts as the antigen source. Molecular analysis of anti-Ro/SSA antibody responses to proteins in the sera was carried out by enzyme-linked immunosorbent assay (ELISA), using recombinant 52 kd and 60 kd fusion proteins ; analysis of anti-La/SSB antibody was performed using recombinant 48 kd fusion protein. The mothers who had both anti-Ro/SSA and La/SSB antibodies had a greater risk of bearing infants with NLE than did the mothers who had only the anti-Ro/SSA antibody. The mothers of children with the skin lesion of NLE were positive for high titers of 48-kd protein. The mothers of children with complete heart block (CHB) were positive for high titers of 52-and 60-kd proteins. The data suggest that anti-La/SSB antibodies influence the development of the skin lesion of NLE, and that anti-52kd Ro/SSA antibodies influence the development of CHB of NLE. Oral corticosteroid therapy beginning before the 16th week of gestation may be effective in the prevention of CHB.