Role of Fibroblast Growth Factor Receptor 2 (FGFR2) in Corneal Stromal Thinning.

Purpose: To determine the role of fibroblast growth factor receptor 2 (FGFR2)-mediated signaling in keratocytes during corneal development, a keratocyte-specific FGFR2-knockout (named FGFR2cKO) mouse model was generated, and its phenotypic characteristics were determined.

Methods: A FGFR2cKO mouse model was generated by the following method: FGFR2 flox mice were crossed with the inducible keratocyte specific-Cre mice (Kera-rtTA/tet-O-Cre). Both male and female FGFR2cKO- and control mice (1 to 3-months-old) were analyzed for changes in corneal topography and pachymetry maps using the optical coherence tomography (OCT) method.

Modeling Keratoconus Using Induced Pluripotent Stem Cells.

Purpose: To model keratoconus (KC) using induced pluripotent stem cells (iPSC) generated from fibroblasts of both KC and normal human corneal stroma by a viral method.

Methods: Both normal and KC corneal fibroblasts from four human donors were reprogramed directly by delivering reprogramming factors in a single virus using 2A "self-cleaving" peptides, using a single polycistronic lentiviral vector coexpressing four transcription factors (Oct 4, Sox2, Klf4, and Myc) to yield iPSC. These iPS cells were characterized by immunofluorescence detection using of stem cell markers (SSEA4, Oct4, and Sox2).

Downregulation of β-actin gene and human antigen R in human keratoconus.

Purpose: The purpose of this study was to determine the expression levels and regulation of β-actin in the stroma of keratoconus (KC) and normal corneas.

Methods: A total of 15 different human corneas from both KC and normal individuals were used for this study. Additionally, 3 Fuch's dystrophic corneas were also used.

Stem cell markers in the human posterior limbus and corneal endothelium of unwounded and wounded corneas.

Purpose: The corneal endothelium is a monolayer of cells in the posterior cornea that is responsible for maintaining a clear cornea. Corneal endothelial cells may be induced to divide, but it has been held that they do not divide in the normal cornea of an adult human. Some studies have suggested that a stem cell population for the corneal endothelium exists.

Molecular changes in selected epithelial proteins in human keratoconus corneas compared to normal corneas.

Purpose: The purpose of the study was to determine molecular changes in selected epithelial proteins in human keratoconus (KC) corneas compared to normal corneas.

Methods: Two-dimensional (2-D) gel electrophoretic profiles of epithelial cell proteins from normal and keratoconus corneas were compared, and the selected protein spots that showed either up- or downregulation were identified. The desired spots were identified after trypsin digestion and mass spectrometric analysis.

L-arginine-threonine-arginine (RTR) tetramer peptide inhibits ulceration in the alkali-injured rabbit cornea.

Purpose: Proline-glycine-proline (PGP) peptides have been identified as inflammatory mediators initiating neutrophil invasion into alkali-injured cornea. The complementary peptide, arginine-threonine-arginine (RTR), has been shown to bind to the PGP sequence and impede neutrophil infiltration. A prior study showed that L-RTR tetramer and D-RTR tetramer, used alternately (14 times a day), resulted in significantly reduced incidences of corneal ulceration and severity.

Fibrin sealant in corneal stem cell transplantation.

Purpose: To determine if transplanted corneal epithelial stem cells are safely and efficiently attached to the deficient limbal niche with use of fibrin sealant. The primary outcome is measured with respect to the stability of the transplant, with secondary qualitative evaluations of inflammation, patient comfort, speed of operation, and incidence of complications.

Methods: This retrospective case study examined a total of 114 corneal stem cell reconstructions performed in 95 patients from 1996 to 2004 using corneal stem cells primarily, with a minority of amnion alone, or both.

Permanent corneal edema resulting from the treatment of PTK corneal haze with mitomycin: a case report.

A 39-year-old man underwent phototherapeutic keratectomy via excimer laser for recurrent corneal erosions secondary to basement membrane dystrophy with the subsequent development of irregular astigmatism and central stromal opacity. The cornea was scraped and treated with 0.02% mitomycin C using a total of 14 drops over a period of 6 days.