The Ro60 autoantigen binds endogenous retroelements and regulates inflammatory gene expression.

Autoantibodies target the RNA binding protein Ro60 in systemic lupus erythematosus (SLE) and Sjögren's syndrome. However, it is unclear whether Ro60 and its associated RNAs contribute to disease pathogenesis. We catalogued the Ro60-associated RNAs in human cell lines and found that among other RNAs, Ro60 bound an RNA motif derived from endogenous Alu retroelements. Alu transcripts were induced by type I interferon and stimulated proinflammatory cytokine secretion by human peripheral blood cells. Ro60 deletion resulted in enhanced expression of Alu RNAs and interferon-regulated genes. Anti-Ro60-positive SLE immune complexes contained Alu RNAs, and Alu transcripts were up-regulated in SLE whole blood samples relative to controls. These findings establish a link among the lupus autoantigen Ro60, Alu retroelements, and type I interferon.

Anti-D concentrations in fetal and maternal serum and amniotic fluid in rhesus allo-immunised pregnancies.

OBJECTIVE: To investigate the relation between anti-D concentrations in maternal serum, fetal serum and amniotic fluid, and the development of fetal anaemia. DESIGN: Observational cross sectional and longitudinal study. SETTING: Regional referral centre. SUBJECTS: Sixty-one women undergoing fetal blood sampling at 19 to 36 weeks' gestation for fetal blood and haematocrit estimation for the management of Rh (D) allo-immunisation. Thirty-eight pregnancies (7 with an Rh (D) negative fetus) were tested only once but the rest had two to five fetal blood samplings. INTERVENTIONS: Ultrasound guided fetal blood sampling and amniocentesis, and automated analysis of anti-D antibody quantitation. RESULTS: There were strong correlations between maternal serum, fetal serum and amniotic fluid anti-D concentrations. Analyses of both longitudinal and cross sectional data demonstrated a decrease of the maternal/fetal serum anti-D ratio with gestation. In pregnancies with Rh (D) negative fetuses the maternal/fetal anti-D ratio was significantly lower (P < 0.0001) than in those with Rh (D) positive fetuses. The degree of fetal anaemia (delta haematocrit) was correlated with maternal serum and amniotic fluid anti-D concentrations (r = -0.55, n = 54, P < 0.0001; r = -0.57, n = 44, P < 0.0001, respectively) but there was a weaker correlation with fetal serum anti-D (r = 0.37, n = 54, P < 0.01). CONCLUSION: Anti-D concentrations in maternal serum, fetal serum and amniotic fluid are correlated with fetal anaemia. The decrease in maternal/fetal anti-D ratio with gestation suggests an increase in placental permeability for anti-D with advancing pregnancy.

The significance of anti-Kell sensitization in pregnancy.

In a 10-year period, 407 of 350,000 pregnancies showed maternal anti-Kell allo-immunization, i.e., an incidence of 1.16 per 1000 pregnancies. About 88% of Kell immunized women gave a history of previous transfusion. There were 51 pregnancies with Kell positive partners (all Kk) resulting in 10 Kell positive babies, of whom six had a positive direct antiglobulin test (DAGT). There were two stillbirths due to haemolytic disease of the newborn, when the maternal anti-Kell titres were 1/256. One baby was severely anaemic and given a top-up transfusion, and two babies were jaundiced and given phototherapy. A policy for management of Kell sensitized pregnancies is outlined, based upon maternal anti-Kell titre and where appropriate fetal blood sampling.

Production of additional atypical alloantibodies in Rh(D)-sensitized pregnancies managed by intrauterine investigation methods.

The production of additional atypical alloantibodies by previously Rh(D)-alloimmunized antenatal patients can complicate the clinical management of both mother and fetus. The relative risks of stimulating additional antibodies following the use of intrauterine investigation methods currently used for the management of haemolytic disease of the newborn have been assessed. A significantly (P less than 0.05, X2) greater number of additional antibodies were detected during pregnancy in the group of pregnancies managed by intrauterine transfusion (IUT) (3/29) than in those managed without recourse to intrauterine investigation (0/50), although one of the patients in the IUT group produced a further antibody following a fetal blood sample but before an IUT had been carried out. The number of additional antibodies detected post-delivery was significantly greater (P less than 0.02) in pregnancies managed by intrauterine transfusion (2/10) than in those managed by fetal haematocrit determination alone (0/28).