COL15A1 and idiopathic pulmonary fibrosis: S8B, data file S2); 3) up-regulation of collagen and fibrotic gene signatures containing multiple human IPF genes [COL1A1, COL15A1, FBN1, FN1, TNC, consistent with mouse gene signatures; (Fig. 6A, B, F, and H)] with increased collagen and SMA protein shown by IHC (fig.