title: Immunoregulatory Role of HLA-G in Allergic Diseases.
abstract: Allergic diseases are sustained by a T-helper 2 polarization leading to interleukin-4 secretion, IgE-dependent inflammation, and mast cell and eosinophil activation. HLA-G molecules, both in membrane-bound and in soluble forms, play a central role in modulation of immune responses. Elevated levels of soluble HLA-G (sHLA-G) molecules are detected in serum of patients with allergic rhinitis to seasonal and perennial allergens and correlate with allergen-specific IgE levels, clinical severity, drug consumption, and response to allergen-specific immunotherapy. sHLA-G molecules are also found in airway epithelium of patients with allergic asthma and high levels of sHLA-G molecules are detectable in plasma and bronchoalveolar lavage of asthmatic patients correlating with allergen-specific IgE levels. Finally, HLA-G molecules are expressed by T cells, monocytes-macrophages, and Langerhans cells infiltrating the dermis of atopic dermatitis patients. Collectively, although at present it is difficult to completely define the role of HLA-G molecules in allergic diseases, it may be suggested that they are expressed and secreted by immune cells during the allergic reaction in an attempt to suppress allergic inflammation.
authors.affiliation: Department of Internal Medicine, Scleroderma Unit, Clinical Immunology Unit, University of Genova, 16132 Genova, Italy.
authors.forename: Giuseppe
authors.identifier: 0000-0002-6403-6905
authors.initials: G
authors.lastname: Murdaca
authors.affiliation: Department of Internal Medicine, Scleroderma Unit, Clinical Immunology Unit, University of Genova, 16132 Genova, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Contini
authors.affiliation: Department of Internal Medicine, Scleroderma Unit, Clinical Immunology Unit, University of Genova, 16132 Genova, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Negrini
authors.affiliation: Department of Internal Medicine, Respiratory and Allergy Diseases Unit, University of Genova, 16132 Genova, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Ciprandi
authors.affiliation: Department of Internal Medicine, Scleroderma Unit, Clinical Immunology Unit, University of Genova, 16132 Genova, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Puppo
mesh_terms: D000483:Alleles; D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000628:therapy; D003876:Dermatitis, Atopic / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000628:therapy; D005260:Female; D059951:HLA-G Antigens / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism / Q000628:therapy; D056747:Immunomodulation; D011247:Pregnancy; D020033:Protein Isoforms; D065631:Rhinitis, Allergic / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000628:therapy
chemical_list: D000485:Allergens; D059951:HLA-G Antigens; D020033:Protein Isoforms