title: Adaptive and innate immune responses in a rat orthotopic lung transplant model of chronic lung allograft dysfunction.
abstract: Acute rejection and respiratory infections are major risk factors for chronic lung allograft dysfunction (CLAD) after lung transplantation. To shed light on the enigmatic etiology of CLAD, we test the following hypotheses using a new experimental model: (i) Alloimmune-independent pulmonary inflammation reactivates alloimmunity. (ii) Alloimmunity enhances the susceptibility of the graft toward pathogen-associated molecular patterns. Pulmonary Fischer 344 to Lewis rat allografts were treated with lipopolysaccharide (LPS), which consistently results in lesions typical for CLAD. Grafts, local lymph nodes, and spleens were harvested before (day 28) and after LPS application (days 29, 33, and 40) for real-time RT-PCR and immunohistochemistry. Mixed lymphocyte reactions were performed on day 33. Four weeks after transplantation, lung allografts displayed mononuclear infiltrates compatible with acute rejection and overexpressed most components of the toll-like receptor system. Allografts but not secondary lymphoid organs expressed increased levels of Th1-type transcription factors and cytokines. LPS induced macrophage infiltration as well as mRNA expression of pro-inflammatory cytokines and effector molecules of innate immunity. Unexpectedly, T-cell reactivity was not enhanced by LPS. We conclude that prevention of CLAD might be accomplished by local suppression of Th1 cells in stable grafts and by controlling innate immunity during alloimmune-independent pulmonary inflammation.
authors.affiliation: Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Member of the German Centre for Lung Research, Justus-Liebig-University Giessen, Giessen, Germany.
authors.forename: Alena
authors.initials: A
authors.lastname: Evers
authors.forename: Srebrena
authors.initials: S
authors.lastname: Atanasova
authors.forename: Gabriele
authors.initials: G
authors.lastname: Fuchs-Moll
authors.forename: Kathrin
authors.initials: K
authors.lastname: Petri
authors.forename: Sigrid
authors.initials: S
authors.lastname: Wilker
authors.forename: Anna
authors.initials: A
authors.lastname: Zakrzewicz
authors.forename: Markus
authors.initials: M
authors.lastname: Hirschburger
authors.forename: Winfried
authors.initials: W
authors.lastname: Padberg
authors.forename: Veronika
authors.initials: V
authors.lastname: Grau
mesh_terms: D064591:Allografts; D000818:Animals; D001989:Bronchiolitis Obliterans / Q000601:surgery; D049109:Cell Proliferation; D002908:Chronic Disease; D016207:Cytokines / Q000378:metabolism; D006085:Graft Survival; D007113:Immunity, Innate; D007150:Immunohistochemistry; D007249:Inflammation; D007962:Leukocytes / Q000166:cytology; D008070:Lipopolysaccharides / Q000737:chemistry; D008168:Lung / Q000473:pathology / Q000503:physiopathology*; D008171:Lung Diseases / Q000601:surgery; D016040:Lung Transplantation; D008264:Macrophages / Q000166:cytology / Q000473:pathology; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D011917:Rats, Inbred Lew; D018417:Th1 Cells / Q000166:cytology
chemical_list: D016207:Cytokines; D008070:Lipopolysaccharides; D012333:RNA, Messenger
keywords: bronchiolitis obliterans syndrome; chronic lung allograft damage; experimental; innate immunity; pulmonary transplantation; rat