Cell adhesion glycoproteins in the human lamina cribrosa

PURPOSE: The distribution of the cell adhesion glycoproteins, laminin, fibronectin, tenascin, vitronectin, thrombospondin, and entactin/nidogen, was examined in the human lamina cribrosa. METHODS: Frozen sections of the optic nerve head from 7 normal human elderly donors were stained by immunohistochemistry. RESULTS: All six glycoproteins were detected in this tissue. While laminin and entactin/nidogen were observed linearly, reflecting the localization of basement membranes, fibronectin was identified diffusely. Marked tenascin immunoreactivity was apparent in the lamina cribrosa, but little or no tenascin staining was detected in the sclera. Vitronectin showed a fine fibrillar staining pattern in the lamina cribrosa, and, to a lesser extent, in the sclera and pial septa. Thrombospondin staining was apparent only in the sclera and the lamina cribrosa, which traversed the optic nerve. CONCLUSIONS: These results indicate that extracellular matrix components in the lamina cribrosa differ from those in the sclera or pial septa. This study is the first report that the human lamina cribrosa includes vitronectin and thrombospondin.