NFKBIZ and idiopathic pulmonary fibrosis: We therefore performed immunostaining of control and IPF lung tissue, identifying IκBζ expression within control alveolar epithelial cells and that this was reduced within IPF alveolar septae (Figure S7D), and confirming through RNA-ISH that NFKBIZ was expressed within alveolar type 2 cells identified by the cell marker surfactant protein C (SFTPC) (Figure 7O).