Figure 2

Healing of an incision-injured cornea of wild-type (WT) or tenascin C-null (knockout (KO)) mouse. Immediately after the incision, the injury in a KO cornea (b) was similar to that in a WT mouse (a). At a higher magnification, epithelium and stroma were found to be perpendicularly cut in both WT (a′) and KO (b′) mice. At day 5, the wound was sealed with fibrotic scar tissue in a WT mouse (c). Arrows indicate the cutting edge of the Descemet’s membrane, although the stromal wound was not closed in a KO mouse (d). In a KO cornea, the epithelium (arrowheads) of the each side of the injury was not connected to each other, remaining the injury unclosed. Higher magnification pictures show that healing epithelium covers the granulation tissue formed in the wound in a WT mouse (c′), whereas in a KO cornea (d′) the healing epithelium does not migrate over the edge of the stromal injury (arrowhead). Arrows indicate the cutting edge of the Descemet’s membrane. At day 10, the granulation (glan) tissue formed in the incision wound seemed more packed in a WT cornea (e), whereas the stromal injury was sealed with an epithelial growth (asterisk) in a KO cornea (f). At a higher magnification the healing epithelium (Epi) covers the granulation tissue (glan) in a WT tissue and in a KO cornea, healing epithelial cells (Epi) seem to fail to connect to the epithelium from the opposite side of the injury and is terminated at the end of the cutting edge of the stroma (arrowhead). Stroma of KO mice at day 5 and 10 was much thicker and seems swollen and acellular as compared with WT stroma (star). Arrows indicate the cutting edge of the Descemet’s membrane. Frames (a′–f′) show the higher magnification pictures of the quadrilateral area in each of Frames (a–f). Epi, corneal epithelium; stroma, corneal stroma; lens, crystalline lens; glan, granulation tissue, black arrows, the break of the Descemet’s membrane; scale bar, 100 μm (a–f) and 25 μm (a′–f′).