TNFα from classically activated macrophages accentuates epithelial to mesenchymal transition in obliterative bronchiolitis.

Abstract

Bronchiolitis obliterans syndrome is characterized by fibrotic obliteration of small airways which severely impairs graft function and survival after lung transplantation. Bronchial epithelial cells from the transplanted lung can undergo epithelial to mesenchymal transition and this can be accentuated by activated macrophages. Macrophages demonstrate significant plasticity and change phenotype in response to their microenvironment. In this study we aimed to identify secretory products from macrophages that might be therapeutic targets for limiting the inflammatory accentuation of epithelial to mesenchymal transition in bronchiolitis obliterans syndrome. TNFα, IL-1β and IL-8 are elevated in bronchoalveolar lavage from lung transplant patients prior to diagnosis of bronchiolitis obliterans syndrome. Classically activated macrophages secrete more TNFα and IL-1β than alternatively activated macrophages and dramatically accentuate TGF-β1-driven epithelial to mesenchymal transition in bronchial epithelial cells isolated from lung transplant patients. Blocking TNFα, but not IL-1β, inhibits the accentuation of epithelial to mesenchymal transition. In a pilot unblinded therapeutic intervention in five patients with progressive bronchiolitis obliterans syndrome, anti-TNFα treatment improved forced expiratory volume in 1 second and 6-min walk distances in four patients. Our data identify TNFα as a potential new therapeutic target in bronchiolitis obliterans syndrome deserving of a randomized placebo controlled clinical trial.

• Authors: L A Borthwick, P A Corris, R Mahida, A Walker, A Gardner, M Suwara, G E Johnson, E J Moisey, M Brodlie, C Ward, J D Perry, A De Soyza, D A Mann, A J Fisher
• Journal: American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons (Am J Transplant) Vol. 13 Issue 3 Pg. 621-33 (Mar 2013) ISSN: 1600-6143 [Electronic] United States
• PMID: 23331923 (Publication Type: Case Reports, Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

Chemical References

• Anti-Inflammatory Agents, Non-Steroidal
• Antibodies, Monoclonal
• Cytokines
• Transforming Growth Factor beta1
• Tumor Necrosis Factor-alpha
• Infliximab

Topics

• Adolescent
• Adult
• Anti-Inflammatory Agents, Non-Steroidal (therapeutic use)
• Antibodies, Monoclonal (therapeutic use)
• Bronchiolitis Obliterans (metabolism, pathology, prevention & control)
• Cytokines (metabolism)
• Epithelial-Mesenchymal Transition (drug effects)
• Female
• Forced Expiratory Volume
• Graft Rejection (metabolism, pathology, prevention & control)
• Humans
• Inflammation (metabolism, pathology, prevention & control)
• Infliximab
• Lung Transplantation
• Macrophage Activation (drug effects)
• Male
• Middle Aged
• Pilot Projects
• Prognosis
• Transforming Growth Factor beta1 (pharmacology)
• Tumor Necrosis Factor-alpha (antagonists & inhibitors, metabolism)
• Young Adult