HLA-G mRNA forms in human trophoblasts and peripheral blood lymphocytes: potential use in prenatal diagnosis.
HLA-G limited polymorphic gene maps to the human major histocompatibility complex (MHC) class I subregion and encodes the molecule which is the only MHC class I antigen expressed on cytotrophoblast cells at the maternal-fetal interface. In this tissue, HLA-G primary mRNA is differentially spliced. We have used a sensitive hot start reverse transcriptase-polymerase chain reaction (RT-PCR) technique to investigate the expression of HLA-G gene in first trimester trophoblasts and adult peripheral blood cells. PCR amplification with HLA-G primers specific of exon 3 has enabled us to demonstrate a novel alternatively spliced form of HLA-G mRNA present in fetal first trimester trophoblasts and lacking exon 4 (HLA-G4). Cloning the whole PCR product and hybridizing recombinant bacterial colonies with specific probes has permitted evaluation of HLA-G4 vs. full length mRNA frequency at approximately 1:200. Moreover, the presence of HLA-G transcripts was found at a very weak level in adult peripheral blood lymphocytes and equally in B- and T-cell populations. These results are relevant in the context of immune tolerance and in the potential use of HLA-G transcripts as a marker for RT-PCR detection of the fetal cells in maternal as a marker for RT-PCR detection of the fetal cells in maternal blood.
Moreau
P
P
CEA-DSV-DPTE, Laboratoire d'Immunoradiobiologie, Hôpital Saint-Louis, Centre Hayem, Paris, France.
Teyssier
M
M
Kirszenbaum
M
M
Gluckman
E
E
Gourand
L
L
Carosella
E
E
Dausset
J
J
D000028:Abortion, Induced; D000328:Adult; D017398:Alternative Splicing; D017931:DNA Primers; D004622:Embryo, Mammalian; D005091:Exons; D005260:Female; D015870:Gene Expression; D006680:HLA Antigens / Q000096:biosynthesis* / Q000235:genetics; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D008214:Lymphocytes / Q000276:immunology*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012333:RNA, Messenger / Q000096:biosynthesis*; D014158:Transcription, Genetic; D014327:Trophoblasts / Q000276:immunology*
D017931:DNA Primers; D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D012333:RNA, Messenger