Maternal blocking factors in human pregnancy are found in plasma not serum.
Pregnancy plasma and sera were evaluated for differential blocking effects in mixed lymphocyte culture reactions. Autologous pregnancy plasma, but not serum was found to contain a specific allogeneic inhibitor for paternal lymphocytes.
D000017:ABO Blood-Group System; D000022:Abortion, Spontaneous / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007959:Lymphocyte Culture Test, Mixed; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D010949:Plasma / Q000276:immunology*; D011247:Pregnancy; D014327:Trophoblasts / Q000276:immunology
D000017:ABO Blood-Group System