Idiopathic Pulmonary Fibrosis (IPF)

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease that causes shortness of breath. The lungs become scarred, stiff and thick and the damage is irreversible. It can be caused by exposure to some environmental pollutants or certain medicines.

The chemicals cause injury to alveolar epithelial cells and this promotes an immuno-inflammatory phase. This phase leads to the expansion of fibroblasts and myofibroblasts which in turn leads to the destruction of the parenchyma – the part of the lung that is responsible for gas transfer.

Interleukin-33 (IL-33) is a cytokine. Cytokines are cell signaling proteins that aid cell-cell communication in an immune response. After pro-inflammatory stimulation expression of IL-33 is upregulated. One way it mediates its biological effects is via interaction with the receptor ST2. However, the role of IL-33 and IL-33/ST2 signaling in establishment of pulmonary inflammation and fibrosis is not well understood.

Fanny et al has studied the role of IL-33, in the regulation of pulmonary inflammation and fibrosis, in a bleomycin induced inflammation and fibrosis model, by immunologic methods and magnetic resonance imaging.  Their results showed that regulation of the IL-33/ST2 axis may attenuate pulmonary fibrosis and enhance recovery.

Reference
Fanny,M., Nascimento,M., Baron,L., Schricke,C., Maillet,I., Akbal,M., Riteau,N., Le bert,M., Quesniaux,v., Ryffel,B., Gombault,A., Meme,S., Meme,W. and Couillin,I. (2018) The IL-33 Receptor ST2 Regulates Pulmonary Inflammation and Fibrosis to Bleomycin. Frontiers in Immunology, volume 9, Article 1476, doi: 10.3389/fimmu.2018.01476.20, 46.