BSG and idiopathic pulmonary fibrosis: EMMPRIN is expressed in type II alveolar epithelial cells at the edges of the fibrotic areas in IPF lung sections [23] and its expression is associated with an induction of MMP-1, -2, -3, -9 as well as α-SMA in the neighboring stromal area [24] implying a role of EMMPRIN in IPF epithelial-stromal interactions [22, 23, 25].