Pathogenesis of idiopathic pulmonary fibrosis - 2011 Lancet review

Idiopathic pulmonary fibrosis (IPF) is a devastating, age-related lung disease of unknown cause that has few treatment options.

IPF was once thought to be a chronic inflammatory process, but current evidence indicates that the fibrotic response is driven by abnormally activated alveolar epithelial cells (AECs).


Interstitial Lung Diseases (ILD) (click to enlarge the image).

Alveolar epithelial cells (AECs) produce mediators that induce the formation of fibroblast and myofibroblast foci through:

- proliferation of mesenchymal cells
- attraction of circulating fibrocytes
- stimulation of the epithelial to mesenchymal transition

The fibroblast and myofibroblast foci secrete excessive amounts of extracellular matrix (collagen), resulting in scarring and destruction of the lung architecture.


Mechanisms of IPF (click to enlarge the image). Image source: PLoS Medicine, Creative Commons license.

References:

Idiopathic pulmonary fibrosis. The Lancet, Volume 378, Issue 9807, Pages 1949 - 1961, 3 December 2011.

Interstitial Lung Diseases (ILD)