title: Antigens of human trophoblasts: a working hypothesis for their role in normal and abnormal pregnancies.
abstract: This report describes the preparation and characterization of antisera to human trophoblast membranes. Rabbit antisera were raised to trophoblast microvilli prepared by differential ultracentrifugation. Antibodies to serum proteins were removed by solid-phase immunoabsorption with normal human serum, and indirect immunofluorescence experiments with cryostat sections of human placentas showed that the absorbed anti-trophoblast sera reacted with trophoblasts as well as with stromal cells and endothelium of chorionic villi. The antisera also produced membrane fluorescence when studied on viable lymphocytes and certain human cell lines. These anti-trophoblast sera were also lymphocytotoxic, and this reaction was abolished by prior absorption of the antisera with leukocytes. The leukocyte-absorbed anti-trophoblast sera retained their ability to react with trophoblasts and certain human cell lines, but no longer reacted with lymphocytes or placental stromal cells and endothelium. Two categories of trophoblast membrane antigens are thus defined: one present on trophoblasts and certain human cells lines (tentatively designated TA(1)), and the other on trophoblasts and lymphocytes, villous fibroblasts, and endothelium (tentatively designated TA(2)). A working hypothesis is proposed stating that normal pregnancy involves the generation of anti-TA(2) subsequent to blastocyst implantation and entrance of trophoblasts into the maternal circulation. This involves a mechanism similar to allogeneic cell stimulation and results in antibodies that block either the recognition or cytotoxicity of TA(1). Failure to mount this response allows TA(1) recognition and trophoblast immunopathology. Experimental and clinical studies in support of this working hypothesis, particularly involving abortion and toxemia, are cited from published reports.
mesh_terms: D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000276:immunology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology*; D014327:Trophoblasts / Q000276:immunology* / Q000648:ultrastructure
references.citation: Lancet. 1977 Dec 10;2(8050):1205-7
references.pmid: 73904
references.citation: Lancet. 1977 Apr 23;1(8017):874-5
references.pmid: 67285
references.citation: Lancet. 1977 Feb 12;1(8007):331-3
references.pmid: 64859
references.citation: Transplant Proc. 1977 Jun;9(2):1379-84
references.pmid: 327635
references.citation: Clin Exp Immunol. 1977 Feb;27(2):365-75
references.pmid: 321168
references.citation: Clin Immunol Immunopathol. 1977 May;7(3):330-5
references.pmid: 872457
references.citation: Transplantation. 1976 Dec;22(6):595-603
references.pmid: 795110
references.citation: Immunology. 1976 Oct;31(4):659-64
references.pmid: 789232
references.citation: N Engl J Med. 1976 Nov 25;295(22):1209-13
references.pmid: 790183
references.citation: Prog Allergy. 1972;16:9-39
references.pmid: 4117680
references.citation: J Exp Med. 1971 Jan 1;133(1):1-18
references.pmid: 4099714
references.citation: Lancet. 1973 Feb 3;1(7797):226-30
references.pmid: 4119376
references.citation: Ann Rheum Dis. 1973 Jul;32(4):283-93
references.pmid: 4131672
references.citation: Adv Immunol. 1971;14:1-84
references.pmid: 4399966
references.citation: Transplant Rev. 1972;12:141-79
references.pmid: 4405567
references.citation: J Clin Invest. 1974 Nov;54(5):1011-9
references.pmid: 4278853
references.citation: Nature. 1976 Aug 26;262(5571):799-802
references.pmid: 60709
references.citation: J Exp Med. 1972 May 1;135(5):1177-84
references.pmid: 4623318
references.citation: JAMA. 1976 Jan 26;235(4):402-4
references.pmid: 54446
references.citation: Nature. 1974 Nov 22;252(5481):302-3
references.pmid: 4431448
references.citation: J Biol Chem. 1976 Jul 10;251(13):4139-46
references.pmid: 932024
references.citation: J Immunol Methods. 1975 Jan;6(3):301-4
references.pmid: 1167882