|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Departments of Internal Medicine and Surgery, University of Michigan, Ann Arbor, Michigan
Submitted 28 July 2006 ; accepted in final form 20 March 2007
Chronic airway rejection, characterized by lymphocytic bronchitis, epithelial cell damage, and obliterative bronchiolitis (OB), limits long-term survival after lung transplantation. The transcription factor early growth response gene-1 (Egr-1) induces diverse inflammatory mediators, some involved in OB pathogenesis. An orthotopic mouse tracheal transplant model was used to determine whether Egr-1 promotes development of airway allograft rejection. Significantly higher Egr-1 mRNA levels were seen in allografts (3.2-fold increase vs. isografts, P = 0.012). Allografts revealed thickening of epithelial and subepithelial airway layers (51 ± 4% luminal encroachment for allografts vs. 20 ± 3% for isografts, P < 0.0001) marked by significant lymphocytic infiltration. Absence of the Egr-1 gene in donor (but not recipient) tissue resulted in significant reduction in luminal narrowing (34 ± 4%, P = 0.0001) with corresponding diminution of T cell infiltration. Egr-1 null allografts exhibited a striking reduction in inducible nitric oxide synthase (iNOS) expression. Effector cytokines previously implicated in OB pathogenesis with known Egr-1 promoter motifs (IL-1
and JE/monocyte chemoattractant protein-1) were reduced in Egr-1 null allografts. These data suggest a paradigm wherein local induction of Egr-1 in tracheal allografts drives expression of inflammatory mediators responsible for lymphocyte recruitment and tissue destruction characteristic of airway rejection.
transplantation; inflammation; lymphocytic bronchiolitis; obliterative bronchiolitis
This article has been cited by other articles:
![]() |
E. Nozik-Grayck, H. B. Suliman, S. Majka, J. Albietz, Z. Van Rheen, K. Roush, and K. R. Stenmark Lung EC-SOD overexpression attenuates hypoxic induction of Egr-1 and chronic hypoxic pulmonary vascular remodeling Am J Physiol Lung Cell Mol Physiol, September 1, 2008; 295(3): L422 - L430. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |