IL-6 was shown to be upregulated in IPF patients 43 and animal models of pulmonary fibrosis 44; furthermore, JAK2 and STAT3 were increased and activated in the hyperplastic alveolar cells of IPF patients 42, which suggested that IL-6/JAK/STAT3 plays a role in lung fibrosis. Here, JAK2 is linked to pulmonary fibrosis.