title: Immunoglobulin subclass (IgG3) restriction of anti-P and anti-Pk antibodies in patients of the rare p blood group.
abstract: Serum antibodies against globoside and ceramide trihexoside, two major glycolipids in human erythrocytes, were investigated in 29 individuals with the rare p blood group. Antibodies of the IgM and of the IgG3 classes were detected. In AB Rh(-) blood donors, who were not of the p blood group, low levels of antibodies of the IgM class were found against P and Pk, whereas no antibodies were detected in cord blood. The increased number of spontaneous abortions and stillbirths observed among the p individuals may relate to the presence of IgG3 antibodies, because such antibodies pass the placental barrier and are efficient in complement activation and in mediating antibody-dependent cytotoxicity.
mesh_terms: D000022:Abortion, Spontaneous; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000032:analysis*; D001789:Blood Group Antigens / Q000276:immunology*; D005260:Female; D005312:Fetal Blood / Q000276:immunology; D005313:Fetal Death; D006017:Glycolipids / Q000302:isolation & purification; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D010127:P Blood-Group System / Q000276:immunology*; D011247:Pregnancy
chemical_list: D000906:Antibodies; D001789:Blood Group Antigens; D006017:Glycolipids; D007074:Immunoglobulin G; D010127:P Blood-Group System