Results of tests with different cellular bioassays in relation to severity of RhD haemolytic disease. Report from nine collaborating laboratories.
Nine different laboratories collaborated in testing sera containing anti-D using various assays with antibody-coated red cells, including antibody-dependent cell-mediated cytotoxicity, either with monocytes (ADCC(M)) or K-lymphocytes (ADCC(L)), monocyte-mediated chemiluminescence and adherence to, and phagocytosis by, peripheral monocytes, U937 cells or cultured macrophages. The samples tested included 14 from 11 mothers of infants with Rh haemolytic disease, 2 monoclonal anti-Ds and 3 samples containing hyperimmune anti-D. The results of the bioassays were graded on a scale of 1-3, as were the degrees of severity of haemolytic disease; results were regarded as correct when the grades of the bioassay result and of the degree of severity were the same. Overall, correct results were obtained with the various assays as follows: ADCC(M), 60%; ADCC(L), 57%; chemiluminescence, 50%; adherence and phagocytosis with peripheral monocytes, 41% (but 71% in one laboratory), and with U937 cells or cultured macrophages, 32%. The ADCC(M) assay, compared with the ADCC(L) assay, not only gave better correlations with the severity of haemolytic disease but also gave higher grades of results with hyperimmune sera and with the monoclonal anti-Ds. Because many of the samples tested were taken after delivery rather than during pregnancy, and because of variations between laboratories, the present results do not conclusively establish the superiority of the ADCC(M) assay in predicting the severity of Rh haemolytic disease.
D000920:Antibody-Dependent Cell Cytotoxicity; D002448:Cell Adhesion; D004899:Erythroblastosis, Fetal / Q000097:blood / Q000276:immunology*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007518:Isoantibodies / Q000032:analysis*; D007753:Laboratories / Q000592:standards*; D008163:Luminescent Measurements; D010587:Phagocytosis; D049590:Postpartum Period; D011247:Pregnancy; D011379:Prognosis; D012204:Rh-Hr Blood-Group System
D007518:Isoantibodies; C033242:RH-antibodies; D012204:Rh-Hr Blood-Group System