|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Medicine, Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States; Department of Veterans Affairs Medical Center, Nashville, Tennessee, United States
2 Department of Medicine, Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
3 Department of Medicine, Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States; Hospital Universitari Germans Trias i Pujol, Badalona, Spain
4 Department of Medicine, Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
5 Department of Medicine, Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States; Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States; Department of Veterans Affairs Medical Center, Nashville, Tennessee, United States
* To whom correspondence should be addressed. E-mail: william.lawson{at}vanderbilt.edu.
Recent evidence suggests that dysfunctional type II alveolar epithelial cells (AECs) contribute to the pathogenesis of idiopathic pulmonary fibrosis (IPF). Based on the hypothesis that disease causing mutations in surfactant protein C (SFTPC) provide an important paradigm for studying IPF, we investigated a potential mechanism of AEC dysfunction suggested to result from mutant SFTPC expression - induction of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR). We evaluated biopsies from 23 IPF patients (including 3 family members with L188Q SFTPC mutations, 10 individuals with familial interstitial pneumonia without SFTPC mutations, and 10 individuals with sporadic IPF) and sections from 10 control lungs. After demonstrating UPR activation in cultured A549 cells expressing mutant SFTPC, we identified prominent expression of UPR markers in AECs in the lungs of patients with SFTPC mutation-associated fibrosis. In individuals with familial interstitial pneumonia without SFTPC mutations and patients with sporadic IPF, we also found UPR activation selectively in AECs lining areas of fibrotic remodeling. Because herpesviruses are found frequently in IPF lungs and can induce ER stress, we investigated expression of viral proteins in lung biopsies. Herpesvirus protein expression was found in AECs from 15/23 IPF patients and co-localized with UPR markers in AECs from these patients. ER stress and UPR activation are found in the alveolar epithelium in patients with IPF and could contribute to disease progression. Activation of these pathways may result from altered surfactant protein processing or chronic herpesvirus infection.
This article has been cited by other articles:
![]() |
D. Xu, R. E. Perez, M. H. Rezaiekhaligh, M. Bourdi, and W. E. Truog Knockdown of ERp57 increases BiP/GRP78 induction and protects against hyperoxia and tunicamycin-induced apoptosis Am J Physiol Lung Cell Mol Physiol, July 1, 2009; 297(1): L44 - L51. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. D. Hardie, S. W. Glasser, and J. S. Hagood Emerging Concepts in the Pathogenesis of Lung Fibrosis Am. J. Pathol., July 1, 2009; 175(1): 3 - 16. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Behr and V. J. Thannickal Update in Diffuse Parenchymal Lung Disease 2008 Am. J. Respir. Crit. Care Med., March 15, 2009; 179(6): 439 - 444. [Full Text] [PDF] |
||||
![]() |
P. W. Noble Epithelial fibroblast triggering and interactions in pulmonary fibrosis Eur. Respir. Rev., December 1, 2008; 17(109): 123 - 129. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Korfei, C. Ruppert, P. Mahavadi, I. Henneke, P. Markart, M. Koch, G. Lang, L. Fink, R.-M. Bohle, W. Seeger, et al. Epithelial Endoplasmic Reticulum Stress and Apoptosis in Sporadic Idiopathic Pulmonary Fibrosis Am. J. Respir. Crit. Care Med., October 15, 2008; 178(8): 838 - 846. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |