In particular, the highly upregulated Wnt5a in mesenchymal cells further mediates the occurrence of bronchopulmonary dysplasia (BPD) with impaired alveolar formation and septal thickening.98–100 In acute lung inflammation, the canonical Wnt signalling pathway in alveolar epithelial cells is usually inhibited by platelet-derived Dickkopf-1 (DKK1). The gene discussed is WNT5A; the disease is bronchopulmonary dysplasia.