Modulation of HLA-G expression in human thymic and amniotic epithelial cells.
Expression of the nonclassical HLA class I antigen, HLA-G, is tightly regulated. HLA-G physiologic expression is mostly restricted to some placental and thymic cell types. Only few established cell lines express HLA-G in vitro. Cytokine-induced expression of HLA-G is hardly observed and also depends on the cell lineage. We assessed expression and cytokine regulation of HLA-G in primary cultures derived from human thymus and amnion epithelial cells, which also express HLA-G in vivo. We show that HLA-G cell surface expression is maintained, but decreases gradually, in primary cultures derived from human thymus and amnion epithelial cells. We also show that IFN-gamma re-induces HLA-G cell surface expression and upregulates classical class I gene expression in both primary cultures and in a thymus derived cell line. We further show that IFN-gamma also upregulates levels of HLA-G transcripts in TEC primary cultures. This study provides evidence that IFN-gamma induction of HLA-G expression occurs in the human amnion and the thymus, and is mediated at the transcriptional level in these tissues. These results also suggest a role for the microenvironment in regulating HLA-G in vivo gene expression in the thymus and amnion membrane.
Lefebvre
S
S
Service de Recherches en Hémato-Immunologie, CEA, DSV/DRM, Institut d'Hématologie, Hôpital Saint-Louis, Cedex, Paris, France.
Adrian
F
F
Moreau
P
P
Gourand
L
L
Dausset
J
J
Berrih-Aknin
S
S
Carosella
E D
ED
Paul
P
P
D000650:Amnion / Q000166:cytology / Q000276:immunology*; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects / Q000276:immunology*; D005434:Flow Cytometry; D006680:HLA Antigens / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007371:Interferon-gamma / Q000494:pharmacology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured
D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D007371:Interferon-gamma