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Induction of Mouse Lung Injury by Endotracheal Injection of Bleomycin
Published on: April 30, 2019
Bone marrow-derived progenitor cells in pulmonary fibrosis
Naozumi Hashimoto1, Hong Jin, Tianju Liu
1Department of Pathology, University of Michigan, Ann Arbor, Michigan 48109, USA.
The Journal of Clinical Investigation
|January 15, 2004
Summary
Pulmonary fibrosis may involve fibroblasts originating from bone marrow (BM) progenitor cells, not just the lungs. This study shows BM-derived cells contribute to collagen production in fibrotic lung lesions.
Area of Science:
- Pulmonary Medicine
- Cell Biology
- Immunology
Background:
- Pulmonary fibrosis pathogenesis is incompletely understood.
- Fibroblast origin in pulmonary fibrosis is debated, with intrapulmonary sources assumed.
- Extrapulmonary origins, particularly from bone marrow (BM), remain unconfirmed.
Purpose of the Study:
- To investigate the potential extrapulmonary origin of fibroblasts in pulmonary fibrosis.
- To determine if bone marrow progenitor cells contribute to fibroblast populations in fibrotic lung tissue.
Main Methods:
- Utilized chimeric mice engrafted with enhanced Green Fluorescent Protein (GFP)-expressing bone marrow.
- Induced pulmonary fibrosis using endotracheal bleomycin (BLM) injection.
- Analyzed GFP-positive cells in fibrotic lesions via flow cytometry and immunohistochemistry.
Main Results:
- Significant increase in GFP-positive cells observed in BLM-induced fibrotic lesions compared to controls.
- A subset of GFP-positive lung cells expressed type I collagen, indicating fibroblast differentiation.
- Isolated GFP-positive fibroblasts produced collagen but did not differentiate into alpha-smooth muscle actin-expressing myofibroblasts.
Conclusions:
- Bone marrow progenitor cells can differentiate into collagen-producing lung fibroblasts during pulmonary fibrosis.
- These BM-derived fibroblasts contribute to fibrotic lesions.
- Further research into the role of BM-derived cells in fibrotic lung diseases is warranted.
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