International Immunology, Vol. 11, No. 6, 889-898,
June 1999
© 1999 Japanese Society for Immunology
HLA-G in the human thymus: a subpopulation of medullary epithelial but not CD83+ dendritic cells expresses HLA-G as a membrane-bound and soluble protein
INSERM U395, CHU Purpan, BP 3028, 31024 Toulouse Cedex 3, France
1 Institute of Histology and Embryology, Karl-Franzens-University, 8010 Graz, Austria
2 Department of Molecular and Experimental Medicine, The Scripps Research Institute, SBR5, La Jolla, CA 92037, USA
3 CNRS UMR 7627, CHU Pitié Salpétrière, 75013 Paris, France
4 Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
Correspondence to: P. Le Bouteiller
The human MHC class Ib gene HLA-G is transcribed and translated in different placental cell subpopulations during pregnancy. In addition to this restricted tissue distribution, HLA-G proteins were also recently detected in the thymus of HLA-G transgenic mice, as well as in some human thymic epithelial cells (TEC). There was a need to further define the phenotype of the HLA-G-expressing cells in the human thymus as well as the type of translated forms that they produce. Using several HLA-G-specific mAb and immunohistochemistry performed on cryosections of human thymi at different ages, we found that the HLA-G-expressing cells are present on medullary cells exhibiting the epithelial morphological type 6. Co-localization experiments performed by double or triple immunofluorescence staining demonstrate that these HLA-G-expressing cells express various cytokeratins, epithelial cell markers but not the CD83 dendritic cell marker. We further show by ELISA measurements that a subset of primary cultured human TEC also expresses soluble HLA-G. Therefore, HLA-G protein tissue distribution is not restricted solely to placental cells. A subpopulation of medullary TEC also expresses HLA-G both at their cell surface and in secreted form, raising the question of the functional significance of such MHC class Ib molecules. Whether thymic soluble and/or membrane-bound HLA-G contribute to inhibit NK cells or to a negative selection of autoreactive T cells which could be harmful in case of pregnancy and/or to a positive selection of viral peptides/HLA-G-restricted CD8+ T cells remains to be demonstrated.
Keywords: ELISA, immunohistochemistry, thymic epithelial cells
The first two authors contributed equally to this work
Transmitting editor: L. Moretta
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  C. Helige, H. Ahammer, A. Hammer, B. Huppertz, H.-G. Frank, and G. Dohr Trophoblastic invasion in vitro and in vivo: similarities and differences Hum. Reprod., October 1, 2008; 23(10): 2282 - 2291. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Moreau, L. Contu, F. Alba, S. Lai, R. Simoes, S. Orru, C. Carcassi, M. Roger, M. Rabreau, and E. D. Carosella HLA-G Gene Polymorphism in Human Placentas: Possible Association of G*0106 Allele with Preeclampsia and Miscarriage Biol Reprod, September 1, 2008; 79(3): 459 - 467. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. D. Carosella, B. Favier, N. Rouas-Freiss, P. Moreau, and J. LeMaoult Beyond the increasing complexity of the immunomodulatory HLA-G molecule Blood, May 15, 2008; 111(10): 4862 - 4870. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S.-m. Yie, L.-h. Li, G.-m. Li, R. Xiao, and C. L. Librach Progesterone enhances HLA-G gene expression in JEG-3 choriocarcinoma cells and human cytotrophoblasts in vitro Hum. Reprod., January 1, 2006; 21(1): 46 - 51. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Wiendl, U. Feger, M. Mittelbronn, C. Jack, B. Schreiner, C. Stadelmann, J. Antel, W. Brueck, R. Meyermann, A. Bar-Or, et al. Expression of the immune-tolerogenic major histocompatibility molecule HLA-G in multiple sclerosis: implications for CNS immunity Brain, November 1, 2005; 128(11): 2689 - 2704. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Blaschitz, H. Juch, A. Volz, H. Hutter, C. Daxboeck, G. Desoye, and G. Dohr The soluble pool of HLA-G produced by human trophoblasts does not include detectable levels of the intron 4-containing HLA-G5 and HLA-G6 isoforms Mol. Hum. Reprod., October 1, 2005; 11(10): 699 - 710. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.S. Hunt, J.L. Pace, P.J. Morales, and C. Ober Immunogenicity of the soluble isoforms of HLA-G Mol. Hum. Reprod., November 1, 2003; 9(11): 729 - 735. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Lenfant, N. Pizzato, S. Liang, C. Davrinche, P. Le Bouteiller, and A. Horuzsko Induction of HLA-G-restricted human cytomegalovirus pp65 (UL83)-specific cytotoxic T lymphocytes in HLA-G transgenic mice J. Gen. Virol., January 1, 2003; 84(2): 307 - 317. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. F. Ryan, R. L. Grendell, D. E. Geraghty, and T. G. Golos A Soluble Isoform of the Rhesus Monkey Nonclassical MHC Class I Molecule Mamu-AG Is Expressed in the Placenta and the Testis J. Immunol., July 15, 2002; 169(2): 673 - 683. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Copeman, R. N.N. Han, I. Caniggia, M. McMaster, S. J. Fisher, and J. C. Cross Posttranscriptional Regulation of Human Leukocyte Antigen G During Human Extravillous Cytotrophoblast Differentiation Biol Reprod, June 1, 2000; 62(6): 1543 - 1550. [Abstract] [Full Text]
|
|