1. FK506-Binding Protein 13 Expression Is Upregulated in Interstitial Lung Disease and Correlated with Clinical Severity. A Potentially Protective Role
- Author
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Spencer Revill, Pierre-Simon Bellaye, Martin Kolb, Karun Tandon, Kjetil Ask, Nathan Hambly, Ehab A. Ayaub, Jean-Claude Cutz, Philipp Kolb, Asghar Naqvi, Tamana Yousof, Martha M. Vaughan, Jiro Kato, Safaa Naiel, Megan Vierhout, Soumeya Abed, Anmar Ayoub, Joel Moss, Manreet Padwal, Anna Dvorkin-Gheva, Victor Tat, and Olivia Mekhael
- Subjects
0301 basic medicine ,Pulmonary and Respiratory Medicine ,Pathology ,medicine.medical_specialty ,Clinical Biochemistry ,Inflammation ,Lung injury ,Bleomycin ,Extracellular matrix ,Idiopathic pulmonary fibrosis ,chemistry.chemical_compound ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Fibrosis ,Pulmonary fibrosis ,medicine ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,Lung ,business.industry ,Interstitial lung disease ,Cell Biology ,respiratory system ,medicine.disease ,respiratory tract diseases ,3. Good health ,medicine.anatomical_structure ,030104 developmental biology ,FKBP ,chemistry ,030228 respiratory system ,Cancer research ,Unfolded protein response ,medicine.symptom ,business ,Myofibroblast ,Hypersensitivity pneumonitis - Abstract
Pulmonary fibrosis is a progressive lung disease characterized by myofibroblast accumulation and excessive extracellular matrix deposition. Endoplasmic reticulum (ER) stress initiates the unfolded protein response (UPR), a cellular stress response pathway that has been implicated in both inflammatory and fibrotic processes. Here, we sought to investigate the role of the 13 kDa FK506-binding protein (FKBP13), an ER stress-inducible molecular chaperone, in various forms of pulmonary fibrosis. We first characterized the gene and protein expression of FKBP13 in lung biopsy samples from 24 patients with idiopathic pulmonary fibrosis (IPF) and 17 control subjects. FKBP13 expression was found to be elevated in the fibrotic regions of IPF lung tissues, and within this cohort, was correlated with declining forced vital capacity and dyspnea severity. FKBP13 expression was also increased in lung biopsies of patients with hypersensitivity pneumonitis, rheumatoid arthritis, and sarcoidosis-associated interstitial lung disease. We next evaluated the role of this protein using FKBP13-/- mice in a bleomycin model of pulmonary fibrosis. Animals were assessed for lung function and histopathology at different stages of lung injury including the inflammatory (Day 7), fibrotic (Day 21) and resolution (Day 50) phase. FKBP13-/- mice showed increased infiltration of inflammatory cells and cytokines at Day 7, increased lung elastance and fibrosis at Day 21, and impaired resolution of fibrosis at Day 50. These changes were associated with an increased number of cells that stained positive for TUNEL and cleaved caspase 3 in the FKBP13-/- lungs, indicating a heightened cellular sensitivity to bleomycin. Our findings suggest that FKBP13 is a potential biomarker for severity or progression of interstitial lung diseases, and that it has a biologically relevant role in protecting mice against bleomycin-induced injury, inflammation and fibrosis.
- Published
- 2021