Serological and Immunological Characteristics of Maternal Anti-Rh(D) Antibodies in Predicting the Severity of Haemolytic Disease of the Newborn

Abstract

A number of factors were analyzed for their predictive value in indicating the severity of haemolytic disease of the newborn (HDN) in 72 infants. The factors investigated were: maternal antibody titre in the indirect antiglobulin test, the number of antibody molecules on sensitized standard red cells evaluated by a radiometric antiglobulin test, the IgG subclass specificity and the reactivity in monocyte-monolayer assay (MMA) and in the rosette assays with lymphocytes and granulocytes from healthy individuals. The results of the MMA correlate much better with the severity of HDN than the antibody titre. In clinically unaffected infants the reactivity in the MMA never exceeded 20%, while in the severe/very severe group it was always greater than 20% (in 95% of very severe cases even above 50%). The number of IgG-bound molecules was also shown to closely correlate with the clinical severity and there was a much greater proportion of severe/very severe cases exhibiting combined IgG1 and IgG3 specificity. Of all the evaluations performed the rosette assays with lymphocytes and granulocytes were found to be less useful in predicting the severity of HDN.

Distribution of IgG Subtypes in Maternal Anti-D Sera and Their Prognostic Value in Rh Haemolytic Disease of the New-Born

“…Significantly higher activ ity of IgG2 was present in one serum. Our data are in agreement with the studies of Zupanska et al [11]: that IgG2 and IgG4 antibodies may be produced. In our study out of 107 patients 7 had exclusively IgG2 and/or IgG4.…”

“…Mothers pos sessing exclusively IgG3 anti-D showed a direct correla tion between Rh titre and severity of HDN. Our data seems to be consistent with Zupanska et al [11], who sug gested that the combined presence of IgGl and IgG3 leads to very severe disease. In the present study the still birth rate was 34.8% when the maternal anti-D had a combina tion of IgGl and IgG3.…”

“…The significance of IgG subtypes in the management of Rh haemolytic disease of the new-born (HDN) has been emphasized by many workers [9][10][11]. Poor correlation be tween Rh titre and fetal outcome has been reported ear lier by us [12], therefore the prognostic value of IgG subtypes was examined.…”

A variable number of tandem repeats polymorphism influences the transcriptional activity of the neonatal Fc receptor α‐chain promoter

“…Previous studies have failed to demonstrate a direct association between the amount of red cell alloantibodies in maternal serum and the severity of HDN. 15,16 The same seems to be true for platelet alloantibodies, as a large prospective study found no correlation between the titre of anti-HPA-1a and severity of FNAIT, 17 although contrasting data have been published. 18,19 One striking explanation for this noncorrelation between maternal alloantibody titre and severity of fetal/ neonatal disease would be a differentially effective transport of IgG alloantibodies across the maternal-fetal barrier.…”

Antenatal tests in the diagnosis and assessment of severity of haemolytic disease (hd) of the fetus and newborn (hdn).

“…Hence, defining mild to moderate hdn is difficult and many of the controversies around the ability of different assays to predict hdn may partly lie in the criteria used to define hdn by different centres. in good hands, to be a good predictor of severity [10,19], while others have found that the ADCC, using either monocytes [9,13] or lymphocytes [20] as effector cells is better and yet, others rely heavily on a CL assay [21,22], There seems to be a good correlation between the quantity of cell bound IgG subclass of the maternal anti-D and its behaviour in the bioassays: ADCC activity and severity of hdn were correlated with the number of cell bound IgG 1 molecules whereas MMA activity, which was not as closely correlated with severity of hd, was most closely correlated with the number of cell-bound lgG3 [13].…”