HLA-G expression defines a novel regulatory T-cell subset present in human peripheral blood and sites of inflammation

• Published in: Blood Vol. 110; no. 2; pp. 568 - 577
• Main Authors: Feger, Ute, Tolosa, Eva, Huang, Yu-Hwa, Waschbisch, Anne, Biedermann, Tilo, Melms, Arthur, Wiendl, Heinz
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 15.07.2007; The Americain Society of Hematology
• Subjects: Analysis of the immune response. Humoral and cellular immunity; Antigens; Biological and medical sciences; CD4-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - immunology; Dendritic Cells - immunology; DNA Primers; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Histocompatibility antigens (hla, h-2 and other systems); Histocompatibility Antigens Class I - genetics; HLA Antigens - genetics; HLA-G Antigens; Humans; Immunobiology; Immunosuppression; Inflammation - immunology; Lymphocyte Activation; Molecular immunology; Muscle, Skeletal - immunology; Muscle, Skeletal - physiopathology; Organs and cells involved in the immune response; Phenotype; Polymerase Chain Reaction; RNA - genetics; RNA - isolation & purification; T-Lymphocyte Subsets - immunology; T-Lymphocytes - immunology; T-Lymphocytes, Regulatory - immunology; Human; HLA-System; Thymus gland; CD4 T lymphocyte; Major histocompatibility system; Cellular immunity; Inflammation; In vitro; Cell subpopulation; Blood; In vivo; T-Lymphocyte; Regulatory cell; Class I histocompatibility antigen; CD8 T lymphocyte
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2006-11-057125

Regulatory T cells can inhibit harmful immunopathologic responses directed against self and foreign antigens and play a major role in controlling autoimmunity. Here we have identified and characterized a subpopulation of CD4 and CD8 T cells in human peripheral blood expressing the immune tolerizing molecule HLA-G. HLA-G–expressing T cells are hypoproliferative, are CD25- and FOXP3-negative, and exhibit potent suppressive properties that are partially mediated by HLA-G. HLA-G–positive (HLA-Gpos) T cells are found at low percentages among CD4 and CD8 single-positive thymocytes, suggesting a thymic origin. The presence of HLA-Gpos T cells at sites of inflammation such as inflamed skeletal muscle in myositis or the cerebrospinal fluid of patients with acute neuroinflammatory disorders suggests an important function in modulating parenchymal inflammatory responses in vivo.