Immunohistochemical Study of HLA‐G Expression in Lung Transplant Recipients

• Published in: American journal of transplantation Vol. 9; no. 6; pp. 1427 - 1438
• Main Authors: Brugière, O, Thabut, G., Pretolani, M., Krawice‐Radanne, I., Dill, C., Herbreteau, A., Poras, I., Moreau, P., Colombat, M., Danel, C., Dehoux, M., Fournier, M., Carosella, E. D., Rouas‐Freiss, N.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-06-2009; Wiley
• Subjects: Adult; Biological and medical sciences; Bronchi - metabolism; Bronchiolitis Obliterans - immunology; Bronchiolitis obliterans syndrome; Chronic obstructive pulmonary disease, asthma; Cross-Sectional Studies; Female; Graft Rejection - immunology; Histocompatibility Antigens Class I - biosynthesis; HLA Antigens - biosynthesis; HLA-G Antigens; HLA‐G; Humans; Immunohistochemistry; Lung - virology; lung transplantation; Lung Transplantation - immunology; Male; marker; Medical sciences; Middle Aged; Pneumology; rejection; Respiratory Mucosa - metabolism; Retrospective Studies; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Virus Diseases - immunology; Immunohistochemistry; Graft(material); HLA-System; Respiratory disease; Lung; Biological marker; Transplantation; Gene expression; Homotransplantation; Respiratory system; HLA-G; Syndrome; Rejection; Anatomic pathology; Treatment; Bronchiolitis obliterans syndrome; Surgery; marker; Graft; Bronchus disease; Bronchiolitis obliterans; lung transplantation; Class I histocompatibility antigen
• ISSN: 1600-6135; 1600-6143
• DOI: 10.1111/j.1600-6143.2009.02650.x

Human leukocyte antigen‐G (HLA‐G), a nonclassical HLA class I protein, promotes immune tolerance of solid‐organ allografts, yet its role in lung transplantation (LTx) is unknown. We examined the expression of HLA‐G in lung allografts through immunohistochemistry by a cross‐sectional study of 64 LTx recipients, classified into four groups (stable patients, acute rejection [AR], bronchiolitis obliterans syndrome [BOS] and symptomatic viral shedders). A marked expression of HLA‐G in bronchial epithelial cells (BEC) was frequently observed in stable recipients (n = 18/35 [51%]), but not in patients with AR (n = 14) or with BOS (n = 8). HLA‐G was also expressed by 4 of 7 symptomatic viral shedders. In addition, HLA‐G‐positive patients from the stable group (n = 35) experienced lower incidence of resistant AR and/or BOS during long‐term follow‐up, as compared with their HLA‐G‐negative counterparts. Finally, in vitro data showed that interferon‐γ, a cytokine present in lung allograft microenvironment, upregulated HLA‐G mRNA and protein expression in primary cultured human BEC. We conclude that HLA‐G expression in the bronchial epithelium of lung allograft is elevated in some LTx recipients in association with their functional stability, suggesting a potential role of HLA‐G as a tolerance marker.
HLA‐G expression in the bronchial epithelium of lung allograft is elevated in some LTx recipients in association with their functional stability.