Corticosteroid and doxycycline suppress MMP-9 and inflammatory cytokine expression, MAPK activation in the corneal epithelium in experimental dry eye.

We investigated the effects of corticosteroid and doxycycline on expression of matrix metalloproteinase (MMP)-9 and inflammatory cytokines and activation of mitogen-activated protein kinase (MAPK) signaling pathways, c-jun N-terminal kinases (JNK), extracellular-regulated kinases (ERK) and p38, in experimental murine dry eye. Experimental dry eye (EDE) was created in C57BL6 mice, with or without or topical treatment consisting of 1% methylprednisolone, 0.025% doxycycline or balanced salt solution four times per day.

Expression and regulation of cornified envelope proteins in human corneal epithelium.

Purpose: Stratified squamous epithelial cells assemble a specialized protective barrier structure on their periphery, termed the cornified envelope. The purpose of this study was to evaluate the presence and distribution of cornified envelope precursors in human corneal epithelium, their expression in human corneal epithelial cell cultures, and the effect of ultraviolet radiation (UVB) and transglutaminase (TG) inhibition on their expression.

Methods: Tissue distribution of small proline-rich proteins (SPRRs) and filaggrin and involucrin was studied in human cornea sections by immunofluorescence staining.

Desiccating stress induces T cell-mediated Sjögren's Syndrome-like lacrimal keratoconjunctivitis.

Chronic dry eye syndrome affects over 10 million people in the United States; it is associated with inflammation of the lacrimal gland (LG) and in some cases involves T cell infiltration of the conjunctiva. We demonstrate that environmental desiccating stress (DS) elicits T cell-mediated inflammation of the cornea, conjunctiva, and LG, but not other organs in mice. The lacrimal keratoconjunctivitis (LKC) was mediated by CD4(+) T cells, which, when adoptively transferred to T cell-deficient nude mice, produced inflammation in the LG, cornea, and conjunctiva, but not in any other organ.

The incidence and risk factors for developing dry eye after myopic LASIK.

Purpose: To determine the incidence of dry eye and its risk factors after myopic laser-assisted in situ keratomileusis (LASIK).

Design: Single-center, prospective randomized clinical trial of 35 adult patients, aged 24 to 54 years, with myopia undergoing LASIK.

Methods: setting and study population: Participants were randomized to undergo LASIK with a superior or a nasal hinge flap.

Gap junction protein connexin 43 serves as a negative marker for a stem cell-containing population of human limbal epithelial cells.

This study evaluated whether the gap junction protein connexin (Cx) 43 could serve as a negative cell surface marker for human corneal epithelial stem cells. Cx43 expression was evaluated in corneo-limbal tissue and primary limbal epithelial cultures. Immunofluorescent staining and laser scanning confocal microscopy showed that Cx43 was strongly expressed in the corneal and limbal suprabasal epithelial cells, but the basal cells of the limbal epithelium were negative.

JNK and ERK MAP kinases mediate induction of IL-1beta, TNF-alpha and IL-8 following hyperosmolar stress in human limbal epithelial cells.

Hyperosmolarity has been recognized to be a pro-inflammatory stress to the corneal epithelium. The cell signalling pathways linking hyperosmolar stress and inflammation have not been well elucidated. This study investigated whether exposure of human limbal epithelial cells to hyperosmotic stress activates the mitogen-activated protein kinase (MAPK) pathways and induces production of pro-inflammatory cytokines, interleukin (IL) -1beta, tumor necrosis factor (TNF) alpha, and the C-X-C chemokine IL-8.

Hyperosmolar saline is a proinflammatory stress on the mouse ocular surface.

Purpose: To investigate whether hyperosmolar stress stimulates production of inflammatory mediators and activates the mitogen-activated protein kinase (MAPK) signaling pathways, c-jun n-terminal kinases (JNKs), extracellular-regulated kinases (ERKs), and p38 on the mouse ocular surface.

Methods: 129SvEv/CD-1 mixed mice were treated with a balanced salt solution (BSS) (305 mOsM) or a hyperosmotic saline solution (HOSS) (500 mOsM). Untreated age-matched mice were used as controls.

Cell size correlates with phenotype and proliferative capacity in human corneal epithelial cells.

This study investigated whether cell size correlates with phenotype and proliferative capacity in human corneal epithelial cells. Primary cultured human corneal epithelial cells were sorted by flow cytometry based on forward scatter profile in comparison with the profile of beads of known size. Four fractions (A, B, C, and D) of cells ranging in size from 10 to 16, 17 to 23, 24 to 30, and >or=31 microm in diameter, respectively, were collected to evaluate their 5-bromo-2-deoxyuridine (BrdU) label retention properties, cell phenotype, and clonal growth capacity on a 3T3 fibroblast feeder layer.

Phase III safety evaluation of cyclosporine 0.1% ophthalmic emulsion administered twice daily to dry eye disease patients for up to 3 years.

Objective: To evaluate cyclosporine 0.1% ophthalmic emulsion over a 1- to 3-year period in moderate to severe dry eye disease patients.

Design: Nonrandomized, multicenter, open-label clinical trial extending 2 ophthalmic cyclosporine phase III clinical trials.

Effect of experimental dry eye on tear sodium concentration in the mouse.

Purpose: To examine the changes in tear volume, sodium concentration, and osmolarity in BALB/c and C57BL/6J mice in response to experimental dry eye (EDE).

Methods: Tear volumes were determined at baseline and after 2 days of EDE using phenol red-impregnated cotton thread. Tear fluid was collected by instilling 1 microl of distilled water into the conjunctival sac and collecting the diluted tear fluid in a 0.

Therapy of progressive rheumatoid arthritis-associated corneal ulceration with infliximab.

Purpose: To review the relative efficacy of the TNFalpha antagonist infliximab in treating 3 patients with rheumatoid arthritis-associated peripheral ulcerative keratitis.

Methods: Review of the clinical course of 3 nonconsecutive patients with progressive rheumatoid arthritis-associated peripheral ulcerative keratitis who were initially treated with conventional immunosuppressant therapy and subsequently treated with infliximab.

Results: All 3 patients experienced progressive corneal ulceration on oral prednisone and weekly oral or intramuscular methotrexate.

Partial enrichment of a population of human limbal epithelial cells with putative stem cell properties based on collagen type IV adhesiveness.

The concept that corneal epithelium stem cells reside in limbus has been recognized for more than a decade, but isolation of these stem cells has not been accomplished. This study was an initial attempt to isolate a population of human limbal epithelial cells enriched for certain putative stem cell properties based on their phenotype. Epithelial cells harvested from fresh human limbal rings and their primary cultures were allowed to adhere to collagen IV-coated dishes for 20 min and 2 hr, sequentially.

Doxycycline inhibits TGF-beta1-induced MMP-9 via Smad and MAPK pathways in human corneal epithelial cells.

Purpose: To evaluate the effects of TGF-beta1 and doxycycline on production of gelatinase MMP-9 and activation of Smad, c-Jun N-terminal kinase (JNK), extracellular-regulated kinase (ERK), and p38 mitogen-activated protein kinase (MAPK) signaling pathways in human corneal epithelial cells.

Methods: Primary human corneal epithelial cells were cultured to confluence. The cells were treated with different concentrations of TGF-beta1 (0.

Matrix metalloproteinase-9 knockout confers resistance to corneal epithelial barrier disruption in experimental dry eye.

Altered corneal epithelial barrier function is the cause for ocular irritation and visual morbidity in dry eye disease. Increased matrix metalloproteinase (MMP)-9 activity has been observed in the tear fluid of dry eye patients. To determine the pathogenic role of MMP-9 in the corneal epithelial disease of dry eye, the effects of experimentally induced dry eye on corneal epithelial morphology and barrier function were compared in MMP-9 knockout mice and their wild-type littermates.

ABCG2 transporter identifies a population of clonogenic human limbal epithelial cells.

ABCG2, a member of the ATP binding cassette (ABC) transporters, has been identified as a molecular determinant for bone marrow stem cells and proposed as a universal marker for stem cells. This study investigates ABCG2 expression and its potential as a marker that identifies human limbal epithelial stem cells. ABCG2 expression was evaluated by immunofluorescent and immunohistochemical staining, laser scanning confocal microscopy, flow cytometry, and semiquantitative reverse transcription-polymerase chain reaction.

Topical cyclosporine inhibits conjunctival epithelial apoptosis in experimental murine keratoconjunctivitis sicca.

Purpose: Increased apoptosis in the conjunctival epithelium has been observed in experimental murine keratoconjunctivitis sicca (KCS). Topical cyclosporine (CsA) has been noted to reduce conjunctival epithelial apoptosis in chronic canine and human KCS. The purpose of this study is to determine if topical CsA treatment inhibits conjunctival epithelial apoptosis in a murine model of KCS.

Stimulation of matrix metalloproteinases by hyperosmolarity via a JNK pathway in human corneal epithelial cells.

Purpose: To investigate whether exposure of human corneal epithelial cells to hyperosmotic stress activates the c-Jun NH(2)-terminal kinase (JNK) stress-activated protein kinase (SAPK) pathway, and stimulates production of the matrix metalloproteinases (MMPs): gelatinase (MMP-9), collagenases (MMP-1 and -13), and stromelysin (MMP-3).

Methods: Primary human corneal epithelial cells cultured in normal osmolar medium (312 mOsM) were exposed to media with higher osmolarity (350-500 mOsM) achieved by adding NaCl, with or without SB202190, an inhibitor of the JNK pathway; dexamethasone; or doxycycline for different lengths of time. The conditioned media were collected after 24 hours of exposure for zymography and ELISA.

Experimental dry eye stimulates production of inflammatory cytokines and MMP-9 and activates MAPK signaling pathways on the ocular surface.

Purpose: To evaluate whether experimentally induced dry eye in mice activates mitogen-activated protein kinase (MAPK) signaling pathways, c-Jun N-terminal kinases (JNK), extracellular-regulated kinases (ERK), and p38 and stimulates ocular surface inflammation.

Methods: 129SvEv/CD-1 mixed mice aged 6 to 8 weeks were treated with systemic scopolamine and exposure to an air draft for different lengths of time, from 4 hours to 10 days. Untreated mice were used as the control.

Mucous membrane pemphigoid in a patient with chronic lymphocytic leukemia.

Purpose: To describe a case of mucous membrane pemphigoid (MMP) with ocular manifestations in a patient subsequently diagnosed with B-cell chronic lymphocytic leukemia (CLL).

Methods: Case report and literature review.

Results: A 64-year-old man presented with redness and irritation of both eyes.

A randomized, double-masked, placebo-controlled, multicenter comparison of loteprednol etabonate ophthalmic suspension, 0.5%, and placebo for treatment of keratoconjunctivitis sicca in patients with delayed tear clearance.

Purpose: To evaluate loteprednol etabonate ophthalmic 0.5% suspension, versus placebo for treatment of the inflammatory component of keratoconjunctivitis sicca in patients with delayed tear clearance.

Design: Randomized, double-masked, placebo-controlled clinical trial.

TGF-beta1 stimulates production of gelatinase (MMP-9), collagenases (MMP-1, -13) and stromelysins (MMP-3, -10, -11) by human corneal epithelial cells.

Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of ocular surface diseases. This study investigated the regulated expression of gelatinases (MMP-2 and -9), collagenases (MMP-1 and -13) and stromelysins (MMP-3, -10, and -11) by TGF-beta1 in cultured human corneal epithelial cells. Primary human corneal epithelial cell cultures were grown to confluence and treated with different concentrations (0.

Phenotypic characterization of human corneal epithelial cells expanded ex vivo from limbal explant and single cell cultures.

Cultivated human corneal epithelial cells have been successfully used for corneal reconstruction. Explant and single cell systems are currently used for human corneal epithelial cultivation. This study was conducted to characterize the phenotypes of human corneal epithelial cells expanded ex vivo by these two culture systems with regard to their growth potential, morphology and antigen expression patterns.

Characterization of putative stem cell phenotype in human limbal epithelia.

This study evaluated proposed molecular markers related to stem cell (SC) properties with the intention of characterizing a putative SC phenotype in human limbal epithelia. Human corneal and limbal tissues were cut in the vertical and horizontal meridians for histology, transmission electron microscopy (TEM), and immunostaining. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization were used to evaluate gene expression.

The role of the lacrimal functional unit in the pathophysiology of dry eye.

The majority of dry eye symptoms are due to a chronic inflammation of the lacrimal functional unit resulting in a loss of tear film integrity and normal function. This leads to a reduction in the ability of the ocular surface to respond to environmental challenges. The underlying cause of tear film dysfunction is the alteration of tear aqueous, mucin, and lipid components.

Tear clearance implications for ocular surface health.

Tear clearance/turnover provides a global assessment of the function of the lacrimal functional unit and of tear exchange on the ocular surface. It is an indirect measure of dry eye induced inflammation on the ocular surface. It shows better correlation with the severity of ocular irritation symptoms and corneal epithelial disease in dry eye than the Schirmer 1 test.