Corneal neovascularization is a sight-threatening condition caused by angiogenesis in the normally avascular cornea. Neovascularization of the cornea is often associated with an inflammatory response, thus targeting VEGF-A alone yields only a limited efficacy. The NF-κB signaling pathway plays important roles in inflammation and angiogenesis. Here, we study consequences of the inhibition of NF-κB activation through selective blockade of the IKK complex IκB kinase β (IKK2) using the compound IMD0354, focusing on the effects of inflammation and pathological angiogenesis in the cornea. In vitro, IMD0354 treatment diminished HUVEC migration and tube formation without an increase in cell death and arrested rat aortic ring sprouting. In HUVEC, the IMD0354 treatment caused a dose-dependent reduction in VEGF-A expression, suppressed TNFα-stimulated expression of chemokines CCL2 and CXCL5, and diminished actin filament fibers and cell filopodia formation. In developing zebrafish embryos, IMD0354 treatment reduced expression of Vegf-a and disrupted retinal angiogenesis. In inflammation-induced angiogenesis in the rat cornea, systemic selective IKK2 inhibition decreased inflammatory cell invasion, suppressed CCL2, CXCL5, Cxcr2, and TNF-α expression and exhibited anti-angiogenic effects such as reduced limbal vessel dilation, reduced VEGF-A expression and reduced angiogenic sprouting, without noticeable toxic effect. In summary, targeting NF-κB by selective IKK2 inhibition dampened the inflammatory and angiogenic responses in vivo by modulating the endothelial cell expression profile and motility, thus indicating an important role of NF-κB signaling in the development of pathologic corneal neovascularization.

Background and Purpose: The connexin 43 (Cx43) mimetic peptide Gap27 was designed to transiently block the function of this gap junction. This study was undertaken to investigate the effect of Gap27 on corneal healing, inflammation and neovascularization.Experimental Approach: The effect of Gap27 on wound healing, inflammation and vascularization was assessed in primary human corneal epithelial cells (HCEC)in vitroand whole human corneasex vivo, and in anin vivorat wound healing model.Key Results: Gap27 enhanced the wound closure of HCECin vitroand accelerated wound closure and stratification of epithelium in human corneasex vivo, but did not suppress the corneal release of inflammatory mediators IL‐6 or TNF‐αin vivo. In human corneasex vivo, F4/80 positive macrophages were observed around the wound site.In vivo, topical Gap27 treatment enhanced the speed and density of early granulocyte infiltration into rat corneas. After 7 days, the expressions of TNF‐α and TGFβ1 were elevated and correlated with inflammatory cell accumulation in the tissue. Additionally, Gap27 did not suppress VEGF release in organotypic culture, nor did it suppress early or late VEGFA expression or neovascularizationin vivo.Conclusions and Implications: Gap27 can be effective in promoting the healing of superficial epithelial wounds, but in deep stromal wounds it has the potential to promote inflammatory cell migration and accumulation in the tissue and does not suppress the subsequent neovascularization response. These results support the proposal that Gap27 acts as a healing agent in the transient, early stages of corneal epithelial wounding.

Rosai-Dorfman disease (RDD) is a rare non-neoplastic histiocytic proliferative disorder characterized by painless lymphadenopathy. Extranodal lesions frequently occur in the head and neck regions. We report the clinical and histological features of extranodal RDD in a 43-year-old man with a previously unreported combination of multiple gross anterior epibulbar nodules in the right eye, submucosal masses of nasal septum and trachea, and no lymphadenopathy during the 12-year follow-up. The patient underwent ophthalmological, otolaryngological and systemic evaluation; gallium 67 scintigraphy; bronchoscopy; ophthalmic ultrasound; head and neck CT scan; biopsies of epibulbar, nasal and tracheal tissues; and septoplasty. Histological specimens showed lymphocytophagocytosis and positive immunoperoxidase staining for S100 protein in foamy histiocytes; both features were typical for RDD. No response to topical or systemic steroids or to radiation therapy was recorded. Removal of nasal septum masses resolved nasal obstruction. The diagnosis of RDD requires histological and, in challenging cases, immunohistological specimens and is difficult – especially with pure extranodal localizations as in our case. RDD should be suspected in cases of subconjunctival mass and/or submucosal nasal and tracheal swellings not responding to systemic steroids.

Inflammation in the normally immune-privileged cornea can initiate a pathologic angiogenic response causing vision-threatening corneal neovascularization. Inflammatory pathways, however, are numerous, complex and are activated in a time-dependent manner. Effective resolution of inflammation and associated angiogenesis in the cornea requires knowledge of these pathways and their time dependence, which has, to date, remained largely unexplored. Here, using a model of endogenous resolution of inflammation-induced corneal angiogenesis, we investigate the time dependence of inflammatory genes in effecting capillary regression and the return of corneal transparency. Endogenous capillary regression was characterized by a progressive thinning and remodeling of angiogenic capillaries and inflammatory cell retreat in vivo in the rat cornea. By whole-genome longitudinal microarray analysis, early suppression of VEGF ligand-receptor signaling and inflammatory pathways preceded an unexpected later-phase preferential activation of LXR/RXR, PPARα/RXRα and STAT3 canonical pathways, with a concurrent attenuation of LPS/IL-1 inhibition of RXR function and Wnt/β-catenin signaling pathways. Potent downstream inflammatory cytokines such as Cxcl5, IL-1β, IL-6 and Ccl2 were concomitantly downregulated during the remodeling phase. Upstream regulators of the inflammatory pathways included Socs3, Sparc and ApoE. A complex and coordinated time-dependent interplay between pro- and anti-inflammatory signaling pathways highlights a potential anti-inflammatory role of LXR/RXR, PPARα/RXRα and STAT3 signaling pathways in resolving inflammatory corneal angiogenesis.