As SEMA class 3 proteins, including SEMA3B, necessitate the presence of coreceptor moieties NRP1 or NRP2 before interacting with their signal transducing receptors plexins A1-4, we assessed whether the expression of the SEMA3B coreceptor NRP1 and NRP2 was also perturbed in the lungs of IPF compared with those of healthy controls (36). This evidence concerns the gene SEMA3B and idiopathic pulmonary fibrosis.