Figure 5

Representative histology (A, C [close-up view]; H&E staining) and immunohistochemistry for epimorphin (B, F [close-up view]) and α-smooth muscle actin (D [close-up view]) of scattered fibroblastic foci in early fibrotic areas as Alcian blue positive area (E; AB-PAS staining) for patients with UIP. (A and C) Honeycombing with complete architectural destruction occurred in fibrotic zones. (C and E) Arrowheads indicate scattered fibroblastic foci. In addition to clear immunostaining in the vascular and alveolar walls (arrows), only weak epimorphin immunostaining was seen in scattered fibroblastic foci (arrowheads) (B and F); many α-smooth muscle actin-positive cells (D) and desquamative regenerated alveolar epithelial cells (C) were found. Scale bars = A, B: 200 μm; C–E: 80 μm.