title: Early Growth Response-1 Plays an Important Role in Ischemia-Reperfusion Injury in Lung Transplants by Regulating Polymorphonuclear Neutrophil Infiltration.
abstract: BACKGROUND
  Early growth response-1 (Egr-1) has been shown to be a trigger-switch transcription factor that is involved in lung ischemia-reperfusion injury (IRI).
  
  
  METHODS
  Mouse lung transplants were performed in wild-type (WT) C57BL/6 and Egr1-knockout (KO) mice in the following donor → recipient combinations: WT → WT, KO → WT, WT → KO, and KO → KO to determine whether the presence of Egr-1 in the donor or recipient is the most critical factor for IRI. Pulmonary grafts were retrieved after 18 hours of ischemia after 4 hours of reperfusion. We analyzed graft function by analyzing arterial blood gas and histology in each combination and assessed the effects of Egr1 depletion on inflammatory cytokines that are regulated by Egr-1 as well on polymorphonuclear neutrophil (PMN) infiltration.
  
  
  RESULTS
  Deletion of Egr1 improved pulmonary graft function in the following order of donor → recipient combinations: WT → WT < WT → KO < KO → WT < KO → KO. Polymerase chain reaction assays for Il1B, Il6, Mcp1, Mip2, Icam1, and Cox2 showed significantly lower expression levels in the KO → KO group than in the other groups. Immunohistochemistry demonstrated clear Egr-1 expression in the nuclei of pulmonary artery endothelial cells and PMN cytoplasm in the WT grafts. Flow cytometry analysis showed that Egr1 deletion reduced PMN infiltration and that the extent of reduction correlated with graft function.
  
  
  CONCLUSIONS
  Both graft and recipient Egr-1 played a role in lung IRI, but the graft side contributed more to this phenomenon through regulation of PMN infiltration. Donor Egr-1 expression in pulmonary artery endothelial cells may play an important role in PMN infiltration, which results in IRI after lung transplantation.
authors.affiliation: 1 Department of General Thoracic Surgery and Breast and Endocrinological Surgery, Okayama University Graduate School of Medicine, Okayama, Japan. 2 Department of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Okayama, Japan.
authors.forename: Sumiharu
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Masaomi
authors.initials: M
authors.lastname: Yamane
authors.forename: Osamu
authors.initials: O
authors.lastname: Yoshida
authors.forename: Naohisa
authors.initials: N
authors.lastname: Waki
authors.forename: Mikio
authors.initials: M
authors.lastname: Okazaki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Matsukawa
authors.forename: Takahiro
authors.initials: T
authors.lastname: Oto
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Miyoshi
mesh_terms: D000818:Animals; D002634:Chemotaxis, Leukocyte; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D004195:Disease Models, Animal; D051766:Early Growth Response Protein 1 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D042783:Endothelial Cells / Q000276:immunology / Q000378:metabolism; D018836:Inflammation Mediators / Q000276:immunology / Q000378:metabolism; D008168:Lung / Q000098:blood supply / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D055370:Lung Injury / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D016040:Lung Transplantation / Q000009:adverse effects*; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D020556:Neutrophil Infiltration; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism*; D011651:Pulmonary Artery / Q000276:immunology / Q000378:metabolism; D015427:Reperfusion Injury / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D015398:Signal Transduction; D013997:Time Factors
chemical_list: D016207:Cytokines; D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse; D018836:Inflammation Mediators