Bleomycin-induced pulmonary fibrosis in animals (IPF model)

Idiopathic pulmonary fibrosis (IPF) is a severe chronic lung disease causing irreversible dysfunction of the organ. It is characterized by an abnormal repair process, causing uncontrolled deposition of extracellular matrix (ECM) including collagen, excessive proliferation of fibroblasts, and destruction of the cellular architecture of the lung. Bleomycin-induced pulmonary fibrosis in laboratory animals is a very well-characterized model, which can be used to study pathomechanisms directly related to human pulmonary fibrosis.

The challenge involves single or repeated exposure to bleomycin using a three or four-week protocol. This exposure has been shown to reproduce hallmarks of human fibrosis, including interstitial lung fibrosis, multifocal alveolar emphysema, accumulation of pigment-laden macrophages, and chronic active inflammation.

• In-life assessment of lung function: invasive, repetitive technique; dynamic compliance and lung resistance
• Animal and gross pathology: animal survival, decrease in body weight, increase in lung weight, weight of right ventricle and Fulton index to quantify right heart hypertrophy
  
• Bronchoalveolar lavage: total and differential cell counts by flow cytometry, cytokine levels by ELISA or MSD
• Histology imaging: conventional stainings, histopathology, histomorphometrical analysis, immunohistochemistry, and pathology scoring of fibrosis
  
• Lung tissue analysis: RNA isolation for gene expression analysis, cytokine levels by ELISA or MSD, hydroxyproline assay