OBJECTIVE: Since there is suggestive but, to date, indirect evidence that maternal anti-SSA(Ro) and SSB(La) antibodies are pathogenic in congenital heart block (CHB), we explored the hypothesis that binding to fetal tissues would result in selective depletion of autoantibodies from the neonatal circulation. METHODS: Maternal and umbilical cord levels of anti-48 kDa SSB(La), anti-52 kDa SSA(Ro) and anti-60 kDa SSA(Ro) antibodies were measured by ELISA and immunoprecipitation at parturition in 15 pregnancies complicated by CHB. A control group consisted of 13 pregnancies in which the mother was known to have antibodies to either SSA(Ro) and/or SSB(La) and the children did not have CHB. RESULTS: The ratios of maternal to cord serum levels of anti-48 SSB(La), anti-52 SSA(Ro) and anti-60 kDa SSA(Ro) antibodies ranged from 0.71 to 2.38 in both affected and unaffected pregnancies. The mean ratio obtained for each of the 3 autoantibodies was not significantly different between the 2 groups. Moreover these ratios did not significantly differ from the mean ratios obtained for total IgG levels in either group. CONCLUSION: These data demonstrate that maternal antibodies to all components of the SSA(Ro) SSB(La) system are efficiently transported across the placenta and are not selectively depleted in the circulation of neonates with CHB.
OBJECTIVE: Since there is suggestive but, to date, indirect evidence that maternal anti-SSA(Ro) and SSB(La) antibodies are pathogenic in congenital heart block (CHB), we explored the hypothesis that binding to fetal tissues would result in selective depletion of autoantibodies from the neonatal circulation. METHODS: Maternal and umbilical cord levels of anti-48 kDa SSB(La), anti-52 kDa SSA(Ro) and anti-60 kDa SSA(Ro) antibodies were measured by ELISA and immunoprecipitation at parturition in 15 pregnancies complicated by CHB. A control group consisted of 13 pregnancies in which the mother was known to have antibodies to either SSA(Ro) and/or SSB(La) and the children did not have CHB. RESULTS: The ratios of maternal to cord serum levels of anti-48 SSB(La), anti-52 SSA(Ro) and anti-60 kDa SSA(Ro) antibodies ranged from 0.71 to 2.38 in both affected and unaffected pregnancies. The mean ratio obtained for each of the 3 autoantibodies was not significantly different between the 2 groups. Moreover these ratios did not significantly differ from the mean ratios obtained for total IgG levels in either group. CONCLUSION: These data demonstrate that maternal antibodies to all components of the SSA(Ro) SSB(La) system are efficiently transported across the placenta and are not selectively depleted in the circulation of neonates with CHB.
Authors: Stina Salomonsson; Sven-Erik Sonesson; Lars Ottosson; Saad Muhallab; Tomas Olsson; Maria Sunnerhagen; Vijay K Kuchroo; Peter Thorén; Eric Herlenius; Marie Wahren-Herlenius Journal: J Exp Med Date: 2005-01-03 Impact factor: 14.307