Pulmonary Fibrosis: Causes, Development, Diagnosis, and Treatment withEmphasis on Murine and In vitro Models

Abstract: Excessive extracellular matrix accumulation characterizes pulmonary fibrosis (PF), a degenerative disease of the interstitial lung that worsens with time and leads to respiratory failure. The current review emphasizes the complicated etiology of PF, which includes environmental exposures, genetic predispositions, and concomitant conditions such as autoimmune diseases, followed by its pathophysiology, diagnosis, and treatment strategies. Murine models have significantly improved our understanding of the pathogenesis of PF. For example, studies of bleomycin-induced lung fibrosis in mice have improved our understanding of the inflammation-fibrosis nexus and revealed new treatment targets. Genetic animal models that lack certain cytokines or signaling pathways (e.g., TGF-γ, IL-13) have helped clarify the role of these mediators in fibrosis formation. In vitro studies with fibroblasts and lung epithelial cells have supplemented these findings by allowing for the analysis of cellular responses to fibrogenic stimuli as well as medication screening. The primary methods for diagnosing PF include histopathological exams, imaging examinations, and pulmonary function testing. New non-invasive biomarkers have the potential to improve early monitoring and identification. Antifibrotic drugs, as well as lung transplantation in severe cases, are the only therapy options available at this time. To improve outcomes for patients with pulmonary fibrosis, this review highlights the need for novel therapies that target key pathophysiological processes and are supported by preclinical models.