Figure 4. Immunohistochemistry for fibrin in open TMs in WT (A), tPA^−/− (B), uPA^−/− (C) mice and the only closed TM in uPA^−/− (D) mice at day 9 after perforation.

Arrows indicate fibrin deposition. Scale bar, 200 µm. EEC, external ear canal; MEC, middle ear cavity; TM, tympanic membrane.