Different patterns in the corneal endothelial cell loss after pars plana and pars limbal insertion of the Baerveldt glaucoma implant.

PURPOSE: To assess corneal endothelial cell (CE) loss after pars plana (PP) and pars limbal (PL) insertion of a Baerveldt glaucoma implant (BGI). DESIGN: Retrospective multicenter interventional comparative study. METHODS: We studied central CE loss for 5 years after BGI surgery in 192 eyes. RESULTS: The prevalence of bullous keratopathy (BK) was greater in the PL cohort than in the PP cohort (P = .003). The CE loss after simultaneous PP vitrectomy and tube insertion into the vitreous cavity was 11.9% in the first year, which was greater than that of 2.9% in eyes where the tube was inserted simply into the vitreous cavity after a prior vitrectomy (P = .046). The annual percentage CE loss after the first year decreased unidirectionally in both of those groups and was 1.3% and 1.0% in the fifth year, respectively (P < .001). For limbal insertion, the CE loss in the simple PL cohort was biphasic, decreasing from 10.5% in the first year to 7.0% in the fifth year. Simultaneous cataract and BGI surgery enhanced the CE loss slightly in the first year in the PP and PL cohorts to 13.0% and 14.0%, respectively. However, these increases were not significant (P = .816 and .358, respectively). Low preoperative CE density (P < .001) and insertion site (P = .020) were significant risk factors for the development of BK. CONCLUSIONS: CE loss in the PL and PP cohorts was biphasic and unidirectional, respectively. The difference in annual CE loss became evident over time. PP tube implantation may be advantageous when the preoperative CE density is low.

Novel immunotherapeutic effects of topically administered ripasudil (K-115) on corneal allograft survival.

Corneal allograft survival is mediated by the variety of immunological reactions and wound healing process. Our aim was to explore the effects of topical administration of ripasudil, a selective Rho-associated coiled-coil protein kinase inhibitor, on corneal allograft survival. Ripasudil was administered to mice thrice a day after allogeneic corneal transplantation. Corneal graft survival, opacity, neovascularization, re-epithelization, immune cell infiltration, and mRNA levels of angiogenic and pro-inflammatory factors in the grafted cornea and draining lymph nodes (dLNs) were evaluated with slit-lamp microscopy, immunohistochemistry, flow cytometry, and polymerase chain reaction. Graft survival was significantly prolonged with lower graft opacity and neovascularization scores in 0.4% and 2.0% ripasudil-treated groups, and mRNA levels of angiogenic and pro-inflammatory factors in ripasudil-treated grafted corneas were reduced. Moreover, 0.4% and 2.0% ripasudil reduced CD45+-infiltrated leukocyte frequency, Cd11b and Cd11c mRNA levels, and the frequencies of mature dendritic cells, IFNγ-, and IL-17- producing CD4+T cells in the dLNs of recipients. Re-epithelization rate of the grafted cornea was significantly higher in the 0.4% and 2.0% ripasudil groups than in the control. Topically applied ripasudil prolonged graft survival by downregulating neovascularization and inflammation factors, while promoting corneal re-epithelization, suggesting that ripasudil may be useful for suppressing immunological rejection in corneal transplantation.

Blockade of costimulatory CD27/CD70 pathway promotes corneal allograft survival.

PURPOSE: To determine whether the CD27/CD70 pathway plays a significant role in corneal allograft rejection by investigating the effect of blocking the CD27/CD70 pathway by anti-CD70 antibody on corneal allograft survival. METHODS: Orthotopic penetrating keratoplasty was performed using C57BL/6 donor grafts and BALB/c recipients. Expression of CD27 and CD70 on rejected cornea was examined by immunohistochemistry. Corneal transplant recipients received intraperitoneal injection of anti-CD70 antibody (FR70) or control rat IgG. Alloreactivity was measured by mixed lymphoid reaction (MLR) in recipients administered control rat IgG and those administered anti-CD70 antibody. Corneal expression of IFN-γ and IL-12 was also examined in both groups. Graft opacity was assessed over an 8-week period and graft survival was evaluated using Kaplan-Meier survival curves. Proportion of CD4+CD44+ memory T cells in lymph nodes was measured by flow cytometry. RESULTS: CD4+CD27+ cells and CD11c+CD70+ cells were present in rejected cornea. Anti-CD70 antibody administration suppressed alloreactivity in corneal allograft recipients, and inhibited IFN-γ expression in recipient cornea (p < 0.05). Anti-CD70 antibody suppressed opacity score of recipient cornea and prolonged corneal allograft survival (p < 0.05). Proportion of CD4+CD44+ memory T cells in recipient lymph nodes was reduced by anti-CD70 antibody treatment. CONCLUSION: The CD27/CD70 pathway plays a significant role in corneal allograft rejection by initiating alloreactive Th1 cells and preserving memory T cells. Anti-CD70 antibody administration prolongs corneal allograft survival indicating the potential therapeutic effect of CD27/CD70 pathway blockade on corneal allograft rejection.

Efficacy and safety of retinol palmitate ophthalmic solution in the treatment of dry eye: a Japanese Phase II clinical trial.

PURPOSE: The purpose of this study was to investigate the efficacy and safety of the administration of retinol palmitate (VApal) ophthalmic solution (500 IU/mL) for the treatment of patients with dry eye. PATIENTS AND METHODS: This study included 66 patients with dry eye. After a 2-week washout period, patients were randomized (1:1) into either a VApal ophthalmic solution or a placebo group, and a single drop of either solution was administered six times daily for 4 weeks. Efficacy measures were 12 subjective symptoms, rose bengal (RB) and fluorescein staining scores, tear film breakup time, and tear secretion. Safety measures included clinical blood and urine analyses and adverse event recordings. RESULTS: In comparisons of the two groups, the mean change in RB staining score from baseline was significantly lower in the VApal group at 2 and 4 weeks (P<0.05 and P<0.01, respectively). Furthermore, the fluorescein clearance rate (fluorescein staining score) was significantly higher in the VApal group at 4 weeks (P<0.05). The VApal group showed a significant improvement in blurred vision at 1 and 2 weeks (P<0.01 and P<0.05, respectively), and the mean change in the total score for subjective symptoms from baseline was significantly lower in the VApal group at 1 week (P<0.05). In before- and after-intervention comparisons, the fluorescein and RB staining scores showed improvement in both groups. Improvement was noted for 11 subjective symptoms in the VApal group and for seven symptoms in the placebo group. No significant differences in adverse events and reactions were found between the groups. CONCLUSION: VApal ophthalmic solution (500 IU/mL) is safe and effective for the treatment of patients with dry eye.

[Two cases of conjunctival intraepithelial neoplasia in immunosuppressed patients].

UNLABELLED: Background: Conjunctival intraepithelial neoplasia (CIN) is a precursor lesion of conjunctival squamous cell carcinoma (SCC). CIN recurs frequently but progresses less aggressively than SCC. We report 2 cases of recurrent CIN in immunosuppressed patients. CASE 1: A 60-year-old woman had been taking oral immunosuppressive drugs for 30 years for systemic lupus erythematosus. In 2005, both conjunctival tumor and high serum SCC levels were noted. Biopsy revealed right eye CIN and left eye SCC, and extended resection was performed. In 2008, right eye CIN recurred accompanied by high serum SCC levels and another extended resection was performed. The patient was free from recurrence for 1 year until her death. CASE 2: A 43-year-old woman who had been taking oral immunosuppressive drugs for 3 years for nephrotic syndrome. She had twice undergone right corneal transplantation for keratoconus. In 2011, right conjunctival tumor and high serum SCC levels were noted. Biopsy revealed right eye CIN, for which an extended resection was performed. At present she remains free from recurrence. CONCLUSION: CIN can recur in immunosuppressed patients. We suggest that serum SCC levels be monitored to help detect recurrence.

Atopic Glaucoma: Clinical and Pathophysiological Analysis.

PURPOSE: Open-angle glaucoma associated with severe atopic dermatitis (atopic glaucoma) tends to be severe and difficult to treat because of ocular surface/eye lid inflammation. To determine the validity of regarding atopic glaucoma as a clinical entity, we carried out retrospective analysis and pathologic investigations. MATERIALS AND METHODS: Forty-five cases (62 eyes) of atopic glaucoma were reviewed retrospectively. During surgical treatment, aqueous humor and trabeculectomy specimens were obtained. The aqueous humor samples were analyzed by multiplex cytokine assay. The surgical specimens were analyzed histologically. RESULTS: Atopic glaucoma was often associated with atopic cataracts (43 eyes) and retinal detachments (19 eyes). A history of glucocorticoid medications was absent in 12 cases. A total of 50 eyes required surgical interventions because of advanced visual field defects and/or high intraocular pressures. Bleb-associated postsurgical infections were observed in 7 eyes. Elevated levels of inflammatory cytokines (IL-8 and CCL2) were observed in the aqueous humor samples obtained from atopic glaucoma patients compared with those from senile cataract patients. Ultrastructural analysis of trabecular meshwork tissues obtained from atopic glaucoma patients showed abnormal accumulation of 10 to 30 nm fibers in the corneoscleral meshwork. CONCLUSIONS: We would like to propose atopic glaucoma as a new clinical entity, ranging from pure atopic glaucoma to a mixed type of atopic/steroid-induced glaucoma that should be considered as one of the clinical features of atopic ocular complications.

Genetic characteristics of Haemophilus influenzae and Streptococcus pneumoniae isolated from children with conjunctivitis-otitis media syndrome.

Acute conjunctivitis is the most common ocular disorders among children and frequently concomitant with acute otitis media (AOM) as conjunctivitis-otitis syndrome. In this study, we evaluated prevalence of causative pathogens and PCR-based genotypes of Haemophilus influenzae and Streptococcus pneumoniae among children with conjunctivitis-otitis media syndrome. Nontypeable H. influenzae (NTHi) is identified most often at 61.8% in conjunctiva exudates followed by S. pneumoniae at 28.2% and Moraxella catarrhalis at 19.1%. Genetic ß-lactamase nonproducing ampicillin resistant (gBLNAR) strains of NTHi and genetic penicillin resistant S. pneumoniae (gPRSP) were identified at 72.1% and at 74.2% among conjunctiva isolates by polymerase chain reaction (PCR), respectively. Pneumococcal strains having either ermB or mefE genes were identified at 93.5% among conjunctiva isolates. The restriction fragment of patterns of 89.7% pairs of H. influenzae isolates and 100% pairs of pneumococcal isolates from conjunctiva exudates, middle ear fluids (MEFs) and nasopharyngeal swabs were identical. In contrast to the previous reports, most prevalent strains from conjunctivitis-otitis media syndrome was BLNAR H. influenzae in this study. The causative pathogen responsible for acute conjunctivitis will be originated from the nasopharynx. In the absence of MEFs one can possibly rely on the nasopharyngeal culture to guide an appropriate treatment.

Vernal keratoconjunctivitis with giant papillae on the inferior tarsal conjunctiva.

PURPOSE: In vernal keratoconjunctivitis (VKC), giant papillae are commonly observed on the superior tarsal conjunctiva. We found 3 cases of giant papillae on the inferior tarsal conjunctiva, and diagnosed them as being VKC based on their clinical and histopathological features. METHODS: Three patients with inferior tarsal giant papillae were studied. In 2 patients, the giant papillae were resected for therapeutic purposes. Immunohistochemical analysis was carried out by indirect immunofluorescent staining using anti-CD3, anti-CD20, anti-CD35 antibodies. RESULTS: In all 3 patients, giant papilla formation was observed on the inferior lid margin. Clusters of CD20 B lymphocytes with CD35 follicular dendritic cells, and CD3 marginal zone T lymphocytes, common features of lymphoid neogenesis, were observed. In 2 patients, typical giant papillary formation was also observed on the superior tarsal conjunctiva. In all the patients, topical dexamethasone and tacrolimus treatments were found to be effective. CONCLUSIONS: The giant papillae of VKC can occur not only on the superior tarsal conjunctiva but also on the inferior tarsal conjunctiva. The possibility of the presence of giant papillae on the inferior tarsal conjunctiva should be considered in the clinical examination of patients with VKC.

Establishment of a human corneal epithelial cell line lacking the functional TACSTD2 gene as an in vitro model for gelatinous drop-like dystrophy.

PURPOSE: Gelatinous drop-like corneal dystrophy (GDLD) is characterized by subepithelial amyloid deposition that engenders severe vision loss. The exact mechanism of this disease has yet to be elucidated. No fundamental treatment exists. This study was conducted to establish an immortalized corneal epithelial cell line to be used as a GDLD disease model. METHODS: A corneal tissue specimen was obtained from a GDLD patient during surgery. Corneal epithelial cells were enzymatically separated from the cornea and were dissociated further into single cells. The epithelial cells were immortalized by the lentiviral transduction of the simian virus 40 (SV40) large T antigen and human telomerase reverse transcriptase (hTERT) genes. For the immortalized cells, proliferative kinetics, gene expressions, and functional analyses were performed. RESULTS: The immortalized corneal epithelial cells continued to proliferate despite cumulative population doubling that exceeded 100. The cells showed almost no sign of senescence and displayed strong colony-forming activity. The cells exhibited a low epithelial barrier function as well as decreased expression of tight-junction-related proteins claudin 1 and 7. Using the immortalized corneal epithelial cells derived from a GDLD patient, we tested the possibility of gene therapy. CONCLUSIONS: We established an immortalized corneal epithelial cell line from a GDLD patient. The immortalized cells exhibited cellular phenotypes similar to those of in vivo GDLD. The immortalized cells are thought to be useful for the development of new therapies for treating GDLD corneas and for elucidation of the pathophysiology of GDLD.

Involvement of plasminogen activator inhibitor-1 in the pathogenesis of atopic cataracts.

PURPOSE: Further to our previous report of a genetic association between interferon-gamma (IFN-γ) receptor 1 gene and atopic cataract, we investigated the roles of plasminogen activator inhibitor-1 (PAI-1), a fibrosis-related, IFN-γ downstream molecule, in the pathogenesis of atopic cataracts. METHODS: Cultured lens epithelial cells (LECs) were stimulated by IFN-γ and quantified by PAI-1 mRNA/protein expression. PAI-1 and TGF-ß mRNA expression was quantified using cDNA samples obtained from the lens epithelium of atopic cataract patients (n = 7) and of senile cataract patients (n = 8). The anterior capsules obtained from atopic cataracts (n = 9) were immunostained with anti-PAI-1 and anti-alpha smooth muscle actin (α-SMA) antibodies. PAI-1 gene expression was knocked down by PAI-1 siRNA, and α-SMA expression was examined under TGF-ß1 stimulation. Expression of α-SMA was examined as a pathological hallmark of anterior subcapsular cataracts, commonly observed in atopic cataracts. RESULTS: The IFN-γ stimulation induced PAI-1 mRNA/protein expression in the LECs from 24 to 48 hours after stimulation. The expression of PAI-1 mRNA and TGF-ß1 mRNA was significantly higher in the cDNA samples obtained from the atopic cataracts than those obtained from the senile cataracts. PAI-1-positive immunostaining was observed at the fibrotic lesion of the atopic cataracts, and α-SMA-positive myofibroblasts were observed at the vicinity of the PAI-1-positive lesion in all nine samples examined. PAI-1 gene knockdown resulted in reduced α-SMA expression in the LECs. CONCLUSIONS: The findings of this study suggest that the IFN-γ, PAI-1, and TGF-ß1 are involved in the pathophysiology of atopic cataracts.

Donor-derived, tolerogenic dendritic cells suppress immune rejection in the indirect allosensitization-dominant setting of corneal transplantation.

Significant interest has been focused on the use of ex vivo-manipulated DCs to optimally induce transplant tolerance and promote allograft survival. Although it is understood that donor-derived, tolerogenic DCs suppress the direct pathway of allosensitization, whether such DCs can similarly suppress the indirect pathway remains unclear. We therefore used the murine model of corneal transplantation to address this, as these allografts are rejected in an indirect pathway-dominant manner. Interestingly, recipients administered with donor bone marrow-derived DCregs, generated via culturing with GM-CSF, IL-10, and TGF-ß1, significantly prolonged survival of corneal allografts. Correspondingly, these recipients demonstrated a potent reduction in the frequency of indirectly allosensitized T cells, as determined by ELISPOT. Examination of DCregs relative to mDCs or iDCs showed a resistance to up-regulation of MHC-II and costimulatory molecules, as well as an impaired capacity to stimulate MLRs. In vivo, DCreg administration in corneal-allografted recipients led to inhibition of CD4(+)IFN-γ(+) T cell frequencies and an associated increase in Foxp3 expression in the Treg compartment. We conclude that donor-derived, tolerogenic DCs significantly suppress the indirect pathway, thereby identifying a novel regulatory mechanism for these cells in transplantation.

Vascular endothelial growth factor-C promotes alloimmunity by amplifying antigen-presenting cell maturation and lymphangiogenesis.

PURPOSE: To investigate the role of anti-vascular endothelial growth factor (VEGF)-C therapy in corneal graft survival and concomitant suppression of hem- and lymph-angiogenesis. METHODS: Corneal suture model in BALB/c mice was placed and immunohistochemical staining was performed with CD31/PECAM-1 and LYVE-1 to quantify the level of blood and lymphatic vessels. Corneal transplants were done in BALB/c mice from C57BL/6 mice donors; grafts were subsequently scored for opacity. VEGF-C was blocked in the angiogenesis and transplant model using neutralizing monoclonal anti-VEGF-C (VGX-100) by intraperitoneal injection. To determine the function of VEGF-C in maturation of antigen-presenting cells (APCs), bone marrow-derived dendritic cells were generated and matured in the presence or absence of VEGF-C. RESULTS: VEGF-C expression was demonstrated to be markedly upregulated in corneal graft rejection. VEGF-C blockade, through administration of a VEGF-C blocking monoclonal antibody, suppresses corneal angiogenic responses, inhibits trafficking and maturation of APCs, and significantly improves allotransplant survival. CONCLUSIONS: These data suggest VEGF-C as a potentially important target in corneal transplant pharmacotherapy and immunobiology.

Perlecan-deficient mutation impairs corneal epithelial structure.

PURPOSE: To elucidate the role of perlecan (Hspg2), a large multidomain heparan sulfate proteoglycan expressed in the basement membrane, in the structure of the corneal epithelium. METHODS: A previously developed perlecan-deficient (Hspg2⁻/⁻-Tg) mouse model was used. Histologic analysis of their corneas was performed by light and transmission electron microscopy. The localization of perlecan in the corneas of wild-type (WT) mice and Hspg2⁻/⁻-Tg mice was examined by immunohistochemistry. The effects of perlecan deficiency on corneal epithelial structure was analyzed with respect to the expression of corneal epithelial proliferation and differentiation markers, such as Ki67, cytokeratin12 (K12), connexin43 (Cx43), Notch1, and Pax6 by immunohistochemistry and real-time polymerase chain reaction (PCR). RESULTS: The Hspg2⁻/⁻-Tg mice had microphthalmos and a thinner corneal epithelium compared with that of the WT mice. Perlecan was localized in the corneal epithelial basement membrane in the WT mice, but not in the Hspg2⁻/⁻-Tg mice. The Hspg2⁻/⁻-Tg corneal epithelium exhibited thinner wing cell layers and a decreased number of Ki67-positive cells, but no dead cells, compared with the WT corneal epithelium. Immunohistochemistry and real-time PCR analysis revealed a significantly decreased expression of corneal epithelial differentiation markers such as K12, Cx43, Notch1, and Pax6 in Hspg2⁻/⁻-Tg mice, compared with those of the WT mice. CONCLUSIONS: The findings of this study highlight a strong correlation between the presence of perlecan in the basement membrane and the structure of corneal epithelium and that the perlecan-deficient mutation impairs corneal epithelial structure.

Adhesion, migration, and proliferation of cultured human corneal endothelial cells by laminin-5.

PURPOSE: To investigate the expression of laminin-5 (LM5) and its receptors by human corneal endothelial cells (HCECs) and whether recombinant human LM5 influences adhesion, proliferation, and migration of cultured HCECs. METHODS: The expression of LM5 and its receptors was examined in human donor corneas by immunohistochemistry, reverse transcription-polymerase chain reaction, and flow cytometry. HCECs cultured under serum-free conditions were used for analysis of the biological effects of LM5. Changes in HCEC adhesion and proliferation due to LM5 were evaluated by counting the number of cells. HCEC migration was assessed by quantifying the percentage of wound closure in the wound-healing assay with an image-processing and -analysis software program. RESULTS: Adult HCECs expressed the LM5 receptor α3ß1 integrin, but not LM5 itself. Significantly more cells became adherent to recombinant LM5 (1.0 µg/mL)-coated dishes than to uncoated dishes in the cell adhesion assay. The proliferation of cultured HCECs was moderately promoted by LM5 (1.0 µg/mL) and soluble LM5 (20 ng/mL and 50 ng/mL) in the cell proliferation assay. A significantly higher percentage of wound closure was obtained with medium containing soluble LM5 than with control medium in the wound-healing assay. CONCLUSIONS: HCECs express the LM5 receptor α3ß1 integrin. Recombinant LM5 promotes adhesion, migration, and moderate proliferation of cultured HCECs. It may be a critical factor in promoting HCEC culture and may contribute to the practical use of tissue-engineered HCECs.

The epithelium takes center stage in allergic keratoconjunctivitis.

PURPOSE: To investigate the role of the epithelium in severe allergic conjunctivitis. METHODS: We first investigated the expression of protease-activated receptors (PARs) in cultured human conjunctival epithelial cells and fibroblasts by reverse transcription-polymerase chain reaction. Next, we examined whether mite allergen-stimulated cells release chemokines and whether physiological protease inhibitors such as secretory leukocyte protease inhibitor (SLPI) and α1-antitrypsin can inhibit their production. We also looked at the expression of thymic stromal lymphopoietin (TSLP) in giant papillae of patients with vernal keratoconjunctivitis and examined whether the as Toll-like receptor 3 ligand polyinosinic:polycytidylic acid (poly I:C) can induce expression of TSLP in cultured human conjunctival epithelial cells. RESULTS: PAR 1, PAR2, and PAR3 were expressed in cultured human conjunctival epithelial cells and fibroblasts at mRNA level. These epithelial cells released interleukin (IL) 6 and IL-8, with an upregulation in their gene expression, in response to the serine protease activity of mite allergens. This response was inhibited by SLPI and α1-antitrypsin. Transforming growth factor ß1 decreased the production of SLPI in corneal and conjunctival epithelial cells. TSLP was expressed in giant papillae epithelium in patients with vernal keratoconjunctivitis at mRNA and protein levels. Poly I:C induced expression of TSLP in cultured conjunctival epithelial cells at mRNA level. Costimulation with TSLP and IL-33 had a synergistic effect for IL-13 mRNA expression in cultured human mast cells. CONCLUSIONS: Imbalance between protease of mite allergens and innate protease inhibitors of the epithelium may induce inflammation and disrupt barrier function. Viral infection may induce expression of TSLP via Toll-like receptors and release IL-33 by necrosis. These phenomena promote excessive allergic reactions; hence, the epithelium takes "center stage" in allergic conjunctivitis.

Role of TGF-ß in tissue eosinophilia associated with vernal keratoconjunctivitis.

To determine the role of TGF-ß(1) in the tissue eosinophilia associated with vernal keratoconjunctivitis (VKC), we investigated the immunohistochemical expression of TGF-ß(1) and TGF-ß(1)-related proteins in giant papillae obtained from VKC patients. We also investigated the effect of TGF-ß(1) on production of eotaxin by cultured conjunctival and corneal fibroblasts using ELISA. Finally, the effects of glucocorticoids, cyclosporine, and tacrolimus on eotaxin production by corneal fibroblasts were assessed. Our investigations revealed that eosinophils expressing TGF-ß(1) and TGF-ß(1)-related proteins (such as phosphorylated Smad2, integrin αvß(6), α-smooth muscle actin, type I procollagen, and tenascin-C) were expressed in the giant papillae. TGF-ß(1) and IL-4/IL-13 caused a synergistic increase of eotaxin production in cultured conjunctival and corneal fibroblasts. This effect of TGF-ß(1) and IL-4/IL-13 was inhibited by glucocorticoids, but neither by cyclosporine nor by tacrolimus. In conclusion, TGF-ß(1) has an important role in the tissue eosinophilia associated with VKC.

Evidence of oxidative stress in the pathogenesis of fuchs endothelial corneal dystrophy.

Fuchs endothelial corneal dystrophy (FECD) is a progressive, blinding disease characterized by corneal endothelial (CE) cell apoptosis. Corneal transplantation is the only measure currently available to restore vision in these patients. Despite the identification of some genetic factors, the pathophysiology of FECD remains unclear. In this study, we observed a decrease in the antioxidant response element-driven antioxidants in FECD corneal endothelium. We further demonstrated that nuclear factor erythroid 2-related factor 2, a transcription factor known to bind the antioxidant response element and activate antioxidant defense, is down-regulated in FECD endothelium. Importantly, we detected significantly higher levels of oxidative DNA damage and apoptosis in FECD endothelium compared with normal controls and pseudophakic bullous keratopathy (iatrogenic CE cell loss) specimens. A marker of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine, colocalized to mitochondria, indicating that the mitochondrial genome is the specific target of oxidative stress in FECD. Oxidative DNA damage was not detected in pseudophakic bullous keratopathy corneas, whereas it colocalized with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells in FECD samples. Ex vivo, oxidative stress caused characteristic morphological changes and apoptosis of CE, suggestive of findings that characterize FECD in vivo. Together, these data suggest that suboptimal nuclear factor erythroid 2-related factor 2-regulated defenses may account for oxidant-antioxidant imbalance in FECD, which in turn leads to oxidative DNA damage and apoptosis. This study provides evidence that oxidative stress plays a key role in FECD pathogenesis.

Corneal abnormalities in the NC/Nga mouse: an atopic dermatitis model.

PURPOSE: To study corneal abnormalities in the NC/Nga mouse, which is an animal model of atopic dermatitis. METHODS: To study histopathologic changes of the eyelid, conjunctiva, and cornea, we extracted the eyeballs together with upper and lower eyelids and fixed them for examination by light and electron microscopy or snap-froze them for immunohistochemistry. Transferase mediated-dUTP digoxigenin nick-end labeling staining was performed to detect apoptotic cells. In order to assess eye scratching behavior and the effect of tacroliums hydrate ointment, we made video recordings. RESULTS: Mice kept in a conventional room suffered from various grades of blepharoconjunctivitis and scratched their eyes furiously. Tacrolimus hydrate ointment reduced their eye-scratching behavior. Histopathologic study of the eyelid and conjunctiva showed that this blepharoconjunctivitis was caused by allergic inflammation. Mice with severe blepharoconjunctivitis showed thinning of the corneal epithelium, an irregular interface between the epithelium and stroma, subepithelial deposition of materials, and neovascularization of the stroma. Their corneas were cone shaped. Many transferase mediated-dUTP digoxigenin nick-end labeling-positive cells were recognized among superficial epithelial cells and keratocytes. CONCLUSIONS: NC/Nga mice are a useful animal model of atopic blepharoconjunctivitis. Various corneal disorders in these mice may depend on their eye-scratching behavior.

Ex vivo transfer of Smad7 decreases damage to the corneal endothelium after penetrating keratoplasty.

PURPOSE: To determine whether transient gene transfer and expression of the intracellular antagonist of transforming growth factor beta (TGF-beta), Smad7, to corneal endothelial cells decreases corneal endothelial cell damage after penetrating keratoplasty in a rabbit model. METHODS: Rabbit corneas were transfected ex vivo with replication-deficient adenoviruses encoding Flag-tagged Smad7, Flag-tagged Smad3, or LacZ (termed AdCMV-Smad7, AdCMV-Smad3, AdCMV-LacZ) and then transplanted to normal rabbits. Expression of the exogenous Smads and phosphorylation of endogenous Smad2 in the transplanted corneal endothelium were examined by immunoblotting and immunohistochemistry with anti-Flag or anti-phosphorylated Smad2 antibodies. Cellular density and morphological changes in the corneal endothelium of the transplanted cornea were evaluated by scanning electron microscopy after transplantation of the Smad-transfected corneas. RESULTS: Transplanted AdCMV-Smad7-transfected corneas significantly inhibited the decrease in cellular density and accelerated wound healing at the host-graft junction when compared with transplanted AdCMV-LacZ-transfected corneas. Transplanted AdCMV-Smad3-transfected corneas showed decreased cellular density and delayed wound healing at the host-graft junction. CONCLUSIONS: Ex vivo gene transfer of Smad7 to corneal endothelial cells inhibits the decrease in cellular density and accelerates wound healing after penetrating keratoplasty in rabbits. Thus, modulation of Smad7 expression in corneal endothelial cells may decrease corneal endothelial cell damage after penetrating keratoplasty.