Corneal scarring, a significant cause of global blindness, results from various insults, including trauma, infections, and genetic disorders. The conventional treatment to replace scarred corneal tissues includes partial or full-thickness corneal transplantation using healthy donor corneas. However, only 1 in 70 individuals with treatable corneal scarring can undergo surgery, due to the limited supply of transplantable donor tissue.
View Article and Find Full Text PDFStem Cell Res Ther
January 2024
Background: Mesenchymal stem cells in the adult corneal stroma (named corneal stromal stem cells, CSSCs) inhibit corneal inflammation and scarring and restore corneal clarity in pre-clinical corneal injury models. This cell therapy could alleviate the heavy reliance on donor materials for corneal transplantation to treat corneal opacities. Herein, we established Good Manufacturing Practice (GMP) protocols for CSSC isolation, propagation, and cryostorage, and developed in vitro quality control (QC) metric for in vivo anti-scarring potency of CSSCs in treating corneal opacities.
View Article and Find Full Text PDFFront Cell Infect Microbiol
December 2023
Introduction: causes vision threatening keratitis. The transcription factor regulates virulence factors in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. isolates with mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone.
View Article and Find Full Text PDFPurpose: Descemet stripping only (DSO) is a relatively novel treatment for Fuchs endothelial corneal dystrophy (FECD). In this procedure, a central area of Descemet membrane and endothelium is removed without the insertion of donor tissue. Evaluation of long-term outcomes (≥5 years) after DSO is imperative to establish the validity of this procedure and to determine its role in the management of Fuchs endothelial dystrophy.
View Article and Find Full Text PDFcauses severe vision threatening keratitis. LasR is a transcription factor that regulates virulence associated genes in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. isolates with mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone.
View Article and Find Full Text PDFContact lenses are a safe and effective method for correction of refractive error and worn by an estimated 45 million Americans. Because of the widespread availability and commercial popularity of contact lenses, it is not well appreciated by the public that contact lenses are U.S.
View Article and Find Full Text PDFCorneal blindness due to scarring is conventionally treated by corneal transplantation, but the shortage of donor materials has been a major issue affecting the global success of treatment. Pre-clinical and clinical studies have shown that cell-based therapies using either corneal stromal stem cells (CSSC) or corneal stromal keratocytes (CSK) suppress corneal scarring at lower levels. Further treatments or strategies are required to improve the treatment efficacy.
View Article and Find Full Text PDFPurpose: To assess the incremental burden of corneal transplant surgery for US commercially insured patients with Fuchs endothelial corneal dystrophy (FECD) treated with endothelial keratoplasty (EK) compared to controls.
Methods: The study design was retrospective cohort using IBM MarketScan claims (January 2014-September 2019) and included EK-treated (N=1562) and control patients (N=23,485) having ≥12 months' enrollment before and after diagnosis, who were subsequently matched on select characteristics. The index date was the beginning of the pre-operative period (3 months before EK); synthetic EK index was assigned for controls.
Purpose: Females and males respond differently to a number of systemic viral infections. Differences between females and males with respect to the severity of keratitis caused by Gram-negative bacteria such as are less well established.
Methods: In this study, we injected female and male New Zealand White rabbit corneas with a keratitis isolate of and evaluated the eyes after 48 hours for a number of clinical and microbiological parameters.
Purpose: Prophylactic topical antiseptics used to eliminate bacteria on the ocular surface prior to ocular surgery should be both effective and non-irritating. Five percent povidone iodine (PI) is an accepted antiseptic used for prophylaxis. Dilute 2.
View Article and Find Full Text PDFEnterococcus faecalis are hospital-associated opportunistic pathogens and also causative agents of post-operative endophthalmitis. Patients with enterococcal endophthalmitis often have poor visual outcomes, despite appropriate antibiotic therapy. Here we investigated the genomic and phenotypic characteristics of E.
View Article and Find Full Text PDFIn this study, we tested the hypothesis that the conserved bacterial IgaA-family protein, GumB, mediates microbial pathogenesis associated with Serratia marcescens ocular infections through regulation of the Rcs stress response system. The role of the Rcs system and bacterial stress response systems for microbial keratitis is not known, and the role of IgaA proteins in mammalian pathogenesis models has only been tested with partial-function allele variants of Salmonella. Here, we observed that an Rcs-activated mutant had a >50-fold reduction in proliferation compared to the wild type within rabbit corneas at 48 h and demonstrated a notable reduction in inflammation based on inflammatory signs, including the absence of hypopyons, and proinflammatory markers measured at the RNA and protein levels.
View Article and Find Full Text PDFPurpose: To compare the outcomes of Pseudomonas aeruginosa keratitis (PAK) in contact lens wearers (CLWs) and non-contact lens wearers (non-CLWs) and identify risk factors for poor visual acuity (VA) outcomes in each group.
Design: Retrospective cohort study METHODS: Two hundred fourteen consecutive cases of PAK were included between January 2006 and December 2019. Clinical features, microbiologic results, and treatment course were compared between CLW and non-CLW groups.
Purpose: To determine the clinical outcomes of corneal transplant patients that had positive rim cultures for fungi.
Methods: Retrospective study.
Results: Of 1276 rim cultures obtained between 2009 and 2019, 16 were positive for fungus (incidence of 1.
The corneal endothelium located on the posterior corneal surface is responsible for regulating stromal hydration. This is contributed by a monolayer of corneal endothelial cells (CECs), which are metabolically active in a continuous fluid-coupled efflux of ions from the corneal stroma into the aqueous humor, preventing stromal over-hydration and preserving the orderly arrangement of stromal collagen fibrils, which is essential for corneal transparency. Mature CECs do not have regenerative capacity and cell loss due to aging and diseases results in irreversible stromal edema and a loss of corneal clarity.
View Article and Find Full Text PDFPurpose: To analyze the clinical characteristics, management choices, and outcomes of cases of methicillin-resistant Staphylococcus aureus (MRSA) keratitis.
Design: Retrospective interventional case series.
Methods: Fifty-two culture-proven (52 eyes) cases of MRSA keratitis diagnosed and treated at the University of Pittsburgh Medical Center were identified and reviewed.
Fungal infection after corneal transplantation is a rare, yet potentially devastating, postoperative complication and has become a growing concern for the transplant surgeon and eye banking community. The Eye Bank Association of America (EBAA) has reported an increasing trend in the rate of postkeratoplasty fungal infections and a reversal in the previously documented predominance of bacterial over fungal infections. Additionally, several studies have confirmed a high correlation between positive corneoscleral donor rim fungal cultures and postoperative infections.
View Article and Find Full Text PDFPurpose: Topical vancomycin 5% (50 mg/mL) has been used for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) keratitis, but patient comfort has many clinicians using lower concentrations. We compared the efficacy of different concentrations of vancomycin in the treatment of experimental MRSA keratitis.
Methods: The corneas of 45 rabbits were infected with 2000 colony-forming units (CFUs) of MRSA.
Purpose: The definitive identification of ocular pathogens optimizes effective treatment. Although the types of ocular pathogens are known; there is less definitive information on the prevalence of causative infections including viruses, fungi, and protozoa, which is the focus of this retrospective laboratory review.
Methods: Data used for laboratory certification were reviewed for the detection of bacteria, viruses, fungi, and protozoa, from patients with infectious keratitis, endophthalmitis, and conjunctivitis.