IL17A and pulmonary fibrosis: In acute exacerbation of pulmonary fibrosis, the levels of IL17 and IL23 are increased, and treatment with interleukin-23 antibody can significantly attenuate airway inflammation and fibrosis and reduce IL17 level, suggesting IL23 is essential for the development of acute exacerbation of pulmonary fibrosis (Senoo et al., 2021).