CD274 and pulmonary fibrosis: As PD-L1 inhibition most likely does not limit pulmonary fibrosis by its immune modulatory effects, one could however envision to use inhibitors targeting the underlying mediators of PD-L1 signalling relevant in IPF (i.e., STAT3 and/or antibodies directed against IL-17A; see Figure 1) instead of targeting PD-L1 itself.