[Collagen synthesis in the corneal epithelium. II. Biochemical and electron microscopy studies on cultured epithelial cells of the rabbit cornea]

[Histochemical investigations of acid mucopolysaccharides in corneal wound healing following superficial keratectomy (author's transl)]

In rabbit eyes there was made a central superficial defect into the cornea with a 7.2-mm Trepan/0.35 mm depth. To show alterations in the pattern of acid mucopolysaccharides during wound healing histochemical investigation was carried out in a series of toluidine blue preparations of pH 3,8-5,2 of unfixed frozen corneal sections. Table 1 shows the results of metachromasia after superficial keratectomy. On the first postoperative day metachromasia was extremely reduced in the area of keratectomia. Metachromasia in the surrounding cornea became normal after three days while in the area of corneal defect it lasted a long time, until the normal pattern of acid mucopolysaccharides is reconstructed. After three months the metachromasia was still reduced in the superficial parts of the corneal stroma (Fig. 3). After six months cornea was transparent in the area of ketatectomy with no alterations in the pattern of mucopolysaccharides. This showed the long alterations in the pattern of mucopolysaccharides. This showed the long healing procedure in bradytrophic corneal tissue.

Bilateral recurrence of granular corneal dystrophy in the grafts. A clinico-pathologic study

Clinical, light- and electron-microscopic findings in two sisters with bilateral recurrence of granular corneal dystrophy in the grafts are presented. The clinical pictures and microscopic findings strongly suggest that granular dystrophy may primarily be an epithelial not a stromal disease.

Electron microscopy of the early embryonic development of the human corneal epithelium

The eyes of a human embryo in the 6th week, 11 mm crown-rump (C.R.) length, and of a human embryo in the 7th week, 19 mm C.R. length, were examined. In the embryo of 11 mm C.R. length, the lens vesicle had just detached from the surface ectoderm, the presumptive corneal epithelium. The acellular primary corneal stroma appeared between the lens vesicle and the overlying ectoderm. The fine structure of the ectodermal cells, of their basal lamina, and of the primary stroma is described. In the embryo of 19 mm C.R. length, mesenchymal cells had moved from the periphery into the space between the ectoderm and the lens. There were remarkable changes in the structure of the corneal epithelial cells, in their basal lamina, and in the underlying substances of the primary stroma.

[Contribution to the changes in the epithelium in macular corneal dystrophy (Groenouw's type II) (author's transl)]

In macular corneal dystrophy the epithelial cells display increased activity: they produce proteins and glucosaminoglucans. This may lead to the synthesis of collagen and of pathologic proteoglugans.

Biology in vitro of corneal epithelium and endothelium

Four main areas were explored: 1) the proper medium for culturing corneal tissue; 2) the effect of serum on tissue growth in vitro; 3) the interrelationships in vitro between corneal epithelium and endothelium, and 4) the biology of cultures of whole corneas (organ cultures). Modified Eagle's minimal essential medium (MEM) proved to be an excellent culture fluid. Corneal tissue could be grown in MEM without serum or clot, thus providing a defined culture medium. The biology in vitro of outgrowths of multilayered corneal epithelium and monolayered corneal endothelium are discussed. Contact inhibition between epithelium and endothelium is demonstrated in whole corneal (organ) cultures.

Synthesis of sulfated glycosaminoglycans by the three cell types of the rabbit cornea in culture

Rabbit corneal cells were cultivated for 21 days and then exposed to Na235SO4, a precursor of sulfated glycosaminoglycans (GAG). All 3 cell types of the cornea, the fibroblasts, the epithelial as well as the endothelial cells, synthesize GAG. The fractionation-patterns of the epithelial and endotherlial GAG are almost identical and differ clearly from the one of fibroblastic GAG.

Biosynthesis of glycosaminoglycans by mammalian corneal epithelium and fibroblasts in vitro. I. Isolation and fractionation-differences of GAG from the two cell types

Labeled glycosaminoglycans (GAG) were isolated and fractionated from cultured rabbit corneal epithelium, rabbit or bovine corneal fibroblasts and rabbit bone fibroblasts that had been previously incubated with either Na235SO4 or D-glucosamine-6-3H precursors. Thus it was demonstrated that the epithelium produces GAG. The fractionations indicated that the epithelial cells predominantly synthesize GAG with a lower degree of sulfation than those produced by corneal fibroblasts. The GAG-fractionation-patterns of the corneal epithelium and bone fibroblasts were similar.