LOXL4 and idiopathic pulmonary fibrosis: In our previous work comparing human IPF lung tissue with age-matched control lung tissue, we identified that in bulk IPF lung tissue lysates there are significant increases in the relative expression levels of the collagen modifying enzymes LOXL2, LOXL3, and LOXL4, as well as PLOD2 (also known as lysyl hydroxylase or LH2) (Jones et al., 2018).