Distribution of Type VI Collagen in the Bovine Cornea

Abstract

Using a specific polyclonal antibody against type VI collagen, the distribution of type VI collagen in the bovine cornea was investigated by indirect immunofluorescence microscopy and immunoelectron microscopy. By immunofluorescence, type VI collagen was detectable throughout the stroma. In addition to the uniform but relatively weak signals, a laminar pattern similar to the arrangement of stromal lamellae was clearly seen. Consistent with the immunofluorescent pattern, immunoelectron micrographs showed strong linear reactions located in the interlamellar spaces. The reactions were also observed in the pericellular region of the keratocytes. Epithelium, Descemet’s membrane and endothelium were negative.

Type VI Collagen in Healing Rabbit Corneal Wounds

“…Subsequently, type VI collagen increased during wound healing and was distributed throughout the wounded area. The electron-microscopic immunolo calization for anti-type VI collagen antibody showed the presence of reaction products in the pericellular region of fibroblastic cells as seen in that of keratocytes in normal bovine corneal stroma [9], In these wounds, therefore, type VI colla gen seems to originate from the fibroblastic cells. Moreover, in the 3-week-old wounds, the immunofluorescence showed a laminar pattern as seen in normal corneal stroma, suggesting the regeneration of the lamellar structure by the fibroblastic cells, although the laminar pattern was irregular and incom plete.…”

“…A previous immunohistochemical study by Linsenmayer et al [8] using embryonal chicken cornea (secondary stroma) showed that type VI collagen within each lamella was not a component of the striated collagen fibrils, but was assembled in the form of thin filaments. We have reported that type VI collagen is present in the interlamellar space and in the pericellular region of keratocytes [9]. In the present study, the role of type VI collagen in the healing process of full-thick ness trephinized corneal wounds was investi gated by immunohistochemistry.…”

“…The corneas for the immunohistochemical study were prepared as described previously [9], Briefly, the tissues were fixed in periodate-lysineparaformaldehyde fixative, washed with phosphatebuffered saline (PBS) containing gradient concentra tions of sucrose and embedded in Tissue-Tek OCT compound (Miles Laboratories, Elkhart, Ind., USA) for cryostat sectioning.…”

“…The control sections were exposed to the same staining sequence, except that nonimmunized mouse IgG was substituted for anti-type VI collagen antibody. All other steps were performed as described previously [9], FITC-conjugated goat antimouse im munoglobulins were purchased from Cappel.…”

“…In the control sections, nonimmunized mouse IgG was used in place of anti type VI collagen antibody. All other steps were per formed as described previously [9].…”