Keiko Yakura

Multivariate Analyses of Inflammatory Cytokines in Eyes with Branch Retinal Vein Occlusion: Relationships to Bevacizumab Treatment

PURPOSE To characterize the differential expression of intraocular inflammatory cytokines in eyes with branch retinal vein occlusion (BRVO) and to assess their roles as prognostic determinants of BRVO. METHODS A prospective cohort study of 38 eyes with BRVO. Aqueous humor samples were collected just before the intravitreal injection of bevacizumab and were assessed for 18 cytokines, chemokines, and growth factors. For control, aqueous humor was collected from 28 eyes before cataract surgery. RESULTS In the aqueous of eyes with BRVO, the IL-23, IL-8, IL-6, IL-15, IL-12, and IL-17 levels were significantly higher than that in control eyes. Pretreatment visual acuity was significantly correlated with the concentrations of IL-8, IL-10, IL-2, IL-1β, IL-5, IL-6, IL-23, IL-4, MCP-1, IL-1α, IL-12, IL-13, IFN-γ, and IL-15. The pretreatment nonperfused area (NPA) was significantly correlated with the concentrations of IL-8, IL-2, MCP-1, and IL-6. Logistic regression analyses revealed significant associations between the BRVO and the concentrations of IL-8, IL-23, IL-12, IL-15, IL-10, IL-1β, and IL-13. IL-8 had the highest odds ratio (OR) and was significantly associated with NPA, central retinal thickness (CRT), and visual acuity. Bevacizumab treatment significantly improved visual acuity and CRT after 1 month. Refractoriness to bevacizumab (defined as CRT recovery 1 month after treatment by <90%) was significantly associated with the IL-12 level. CONCLUSIONS Of the induced cytokines in eyes with BRVO, IL-8 was the most significantly associated with the disease parameters of BRVO. IL-12 is most likely a factor that blocks the effect of bevacizumab treatment. (www.umin.ac.jp/ctr number, UMIN000003854.).

Ablation of type I hypersensitivity in experimental allergic conjunctivitis by eotaxin-1/CCR3 blockade

The immune response is regulated, in part, by effector cells whose activation requires multiple signals. For example, T cells require signals emanating from the T cell antigen receptor and co-stimulatory molecules for full activation. Here, we present evidence indicating that IgE-mediated hypersensitivity reactions in vivo also require cognate signals to activate mast cells. Immediate hypersensitivity reactions in the conjunctiva are ablated in mice deficient in eotaxin-1, despite normal numbers of tissue mast cells and levels of IgE. To further define the co-stimulatory signals mediated by chemokine receptor 3 (CCR3), an eotaxin-1 receptor, effects of CCR3 blockade were tested with an allergic conjunctivitis model and in ex vivo isolated connective tissue-type mast cells. Our results show that CCR3 blockade significantly suppresses allergen-mediated hypersensitivity reactions as well as IgE-mediated mast cell degranulation. We propose that a co-stimulatory axis by CCR3, mainly stimulated by eotaxin-1, is pivotal in mast cell-mediated hypersensitivity reactions.

Roles played by toll-like receptor-9 in corneal endothelial cells after herpes simplex virus type 1 infection.

PURPOSE To determine the roles played by toll-like receptor 9 (TLR9) in cultured human corneal endothelial (HCEn) cells after herpes simplex virus type 1 (HSV-1) infection and to characterize the TLR9-mediated antiviral responses. METHOD Immortalized HCEn cells were examined for TLR expression. The upregulation of inflammatory cytokines after HSV-1 infection was determined by real-time RT-PCR or protein array analyses. The TLR9-mediated HSV-1 replication was determined by real-time PCR and plaque assay. To determine whether there was an activation of the signal transduction pathway, HCEn cells that were transfected with pathway-focused transcription factor reporters were examined for promoter activity. RESULTS TLR9 was abundantly expressed intracellularly in HCEn cells. The CpG oligonucleotide, a TLR9 ligand, stimulated the NF-κB activity in HCEn cells. HSV-1 infection also stimulated NF-κB and induced NF-κB -related inflammatory cytokines, including RANTES, IP-10, MCP-2, MIF, MCP-4, MDC, MIP-3α, IL-5, TARC, MCP-1, and IL-6. The induction of these cytokines was significantly reduced by blocking the activity of TLR9. In addition, viral replication in HCEn cells was significantly reduced by the inhibition of TLR9, but was preserved by a concomitant activation of the NF-κB cascade. Of the different HSV-1-induced inflammatory cascade-related transcription factors, TLR9 was found to activate NF-κB, cyclic AMP response element (CRE), and the CCAAT-enhancer-binding proteins (C/EBP) the most. CONCLUSIONS Corneal endothelial cells transcriptionally initiate inflammatory programs in response to HSV-1 infection related to NF-κB, CRE, and C/EBP and express arrays of inflammatory cytokine induction by TLR9. On the other hand, HSV-1 exploits TLR9-mediated NF-κB activation for its own replication.

Assessment of Real-Time Polymerase Chain Reaction Detection of Acanthamoeba and Prognosis Determinants of Acanthamoeba Keratitis

OBJECTIVE To evaluate the diagnostic value of real-time polymerase chain reaction (PCR) for detecting Acanthamoeba in eyes diagnosed with Acanthamoeba keratitis (AK) by conventional tests. In addition, to determine the preoperative prognosis-determining factors in eyes with AK. DESIGN Retrospective, cross-sectional study. PARTICIPANTS A total of 104 eyes of 103 patients who were diagnosed with AK or with bacterial or bacteria-associated keratitis (BK) by conventional tests. METHODS Twenty-nine eyes with AK and 75 eyes with BK were evaluated for Acanthamoeba and bacterial DNA by real-time PCR. The Acanthamoeba copy numbers, bacterial load, and clinical parameters in the patients with AK were assessed for those significantly associated with poor outcome, that is, final visual acuity of <20/50 or requiring keratoplasty, by logistic regression analysis. MAIN OUTCOME MEASURES Acanthamoeba DNA copy number, bacterial DNA copy number, and odds ratio (OR) for poor prognosis. RESULTS The detection of amoebic DNA was 50 times more sensitive by real-time PCR than by conventional cyst counting. The Acanthamoeba copy numbers at the first visit (mean: 4.7×10(5)±3.2×10(5) copies) were significantly correlated with the AK stage, and both were significant risk factors for a poor outcome. The Acanthamoeba DNA copy numbers at the first visit and AK stage had a significantly high risk for poor outcome (OR of Acanthamoeba DNA copy per logarithm of copy numbers: 3.48, 95% confidence interval [CI], 1.04-111.63, P<0.05; OR of AK stage: 2.8 per stage increase, 95% CI, 1.07-7.30, P<0.05, after adjustment of age). In the AK cases with poor outcome, the amoebic DNA was not reduced by more than 90% after 1 month of treatment. The weak amoebic reduction was significantly associated with advanced AK stages or previous use of steroids. Bacterial 16S rDNA was detected in 53.6% of the eyes with AK, but it was not associated with any risk for refractoriness. CONCLUSIONS Real-time PCR was effective in detecting and managing AK. The Acanthamoeba copy number and AK stage at the first visit were significantly associated with poor outcome. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Blocking Mast Cell—Mediated Type I Hypersensitivity in Experimental Allergic Conjunctivitis by Monocyte Chemoattractant Protein-1/CCR2

PURPOSE To characterize the roles played by monocyte chemoattractant protein-1 and its preferential receptor CCR2 (MCP-1/CCL2) in acute allergic inflammation. METHODS The direct effects of MCP-1 were evaluated histologically after a subconjunctival injection of recombinant MCP-1 into naïve mice. The mice were sensitized to ragweed pollen, and allergic conjunctivitis was induced by an allergen challenge. The location of the induced MCP-1 was determined by immunohistochemistry. Anti-MCP-1 antibody and CCR2-specific antagonist, RS 504393, were used to determine whether an inhibition of MCP-1 or CCR2 signals would suppress the allergen-induced immediate hypersensitivity reaction. The effect of blocking CCR2 was tested in vitro with isolated mast cells from connective tissue, to evaluate the co-stimulatory signals mediated by CCR2 in mast cells directly. RESULTS A subconjunctival injection of MCP-1 stimulated conjunctival mast cell degranulation and recruited monocytes/macrophages. In the allergic conjunctivitis model, the allergen-induced MCP-1 protein was located in the monocytes/macrophages in the substantia propria of the conjunctiva. Blocking MCP-1 significantly suppressed the allergen-induced clinical signs and mast cell degranulation without affecting the allergen-specific IgE, or the release of Th2 cytokine from the isolated draining lymph node cells. Inhibition of CCR2 similarly suppressed the acute inflammatory responses. Consistent with the outcome of the disease model, inhibition of CCR2 suppressed allergen-specific degranulation of IgE-primed, isolated conjunctival mast cells. CONCLUSIONS Stimulation of the co-stimulatory axis of CCR2 by MCP-1 is essentially required for mast cell-mediated hypersensitivity reactions in mouse eyes.

Induction of IL-6 in transcriptional networks in corneal epithelial cells after herpes simplex virus type 1 infection.

PURPOSE To determine the transcriptional responses of human corneal epithelial cells (HCECs) after herpes simplex virus type (HSV)-1 infection and to identify the critical inflammatory element(s). METHOD Immortalized HCECs were infected with HSV-1, and the global transcriptional profile determined. Molecular signaling networks were constructed from the HSV-1-induced transcriptomes. The relationships of the identified networks were confirmed by real-time-PCR and ELISA. Contributions of the critical network nodes were further evaluated by protein array analyses as candidates for inflammatory element induction. RESULTS HSV-1 infection induced a global transcriptional response, with 412 genes significantly activated or suppressed compared with mock-infected HCECs (P < 0.05, 2< or 0.5> threshold). Infection by UV-inactivated HSV-1 did not induce significant transcriptional activity. Network analysis showed that the HSV-1-induced transcriptomes were associated with JUN N-terminal kinase, p38, extracellular signal-regulated kinase, and nuclear factor kappa-B signaling pathways. These findings indicate that interleukin (IL)-6 and vascular endothelial growth factor (VEGF) probably serve as critical nodes of signaling events. ELISA and protein array analyses verified the induction of the inflammatory elements by HSV infection. Blocking the induction of IL-6 significantly reduced the expression of 21 cytokines, including CCL7, CCL8, CXCL6, transforming growth factor-beta2, platelet-derived growth factor, interferon-gamma, IL-2, and VEGF, thus confirming the critical role of IL-6. CONCLUSIONS HCECs respond to HSV-1 infection by initiating mitogen-activated protein kinase-related transcriptional events, and IL-6 may serve to induce expression of an array of inflammatory mediators.

Herpes simplex virus type 1-induced transcriptional networks of corneal endothelial cells indicate antigen presentation function.

PURPOSE To determine the transcriptional response of cultured human corneal endothelial (HCEn) cells after herpes simplex virus type (HSV-1) infection and to characterize the primary functional elements and antiviral responses. METHODS Immortalized HCEn cells were infected with HSV-1, and the global transcriptional profile was determined. The transcriptional networks of HCEn cells were constructed, and the inflammatory network nodes were evaluated for induction of candidate inflammatory mediators by protein array analyses. HSV-1-specific allogeneic T cells isolated from HSV-1-infected donors were co-cultured with HSV-1-pulsed HCEn cells, and T cell activation was assessed for antigen-specific proliferation. RESULTS HSV-1 infection induced a global transcriptional activation with 331 genes significantly up- or downregulated compared with mock-infected HCEn cells (P < 0.01; 4< or 0.25> threshold). Network analysis showed that the HSV-1-induced transcriptome was specifically associated with antigen presentation, interferon-related responses, and cellular development, and was characterized by NF-κB and extracellular signal-regulated kinase signaling pathways. The primary associated function in the transcriptome was antigen presentation. Protein array analysis identified significant elevation of genes related to antigen presentation: IL-6, IP-10, HVEML, and interferon-γ. In addition, inflammatory cytokines including IL-8, MCP-1, TIMP-1, RANTES, I-309, MIF, MCP-2, IL-10, and SDF-1, in descending order, were significantly elevated. Mixed lymphocyte reaction assays showed that HSV-1-pulsed HCEn cells stimulated antigen-specific proliferation of allogeneic T lymphocytes. CONCLUSIONS HCEn cells respond to HSV-1 infection by initiating antigen presentation-related inflammatory responses, and they may serve as antigen-presenting cells.

Role of periostin and interleukin-4 in recurrence of pterygia.

PURPOSE To identify the candidate genes for pterygia recurrence from a pterygia transcriptome and to analyze their transcriptional regulation and functional relationships. METHODS Transcriptional networks for pterygia recurrence were constructed using network analysis that was applied to 184 genes that showed a significant twofold change in the whole genome. Of the identified recurrence-related candidate genes in the major networks, periostin and IL-4 were analyzed for transcriptional relationships using pterygia-derived fibroblasts. Immunohistochemical analysis was used to study pterygia tissue. Effector candidate molecule for recurrence periostin was analyzed for cell adhesive function. RESULTS The pterygia transcriptome was divided into four major biological networks with high significance scores (P < 10(-17)). The classifier with the highest accuracy using the support vector machine algorithm was periostin, which was successfully linked to the network of cell cycle, connective tissue development and function, and cell morphology. Analyses using pterygia-derived fibroblasts showed that periostin was required for cell adhesion that was mediated by a presumed pterygia-related extracellular matrix protein, fibronectin. Periostin was found to be transcriptionally induced by IL-4. The IL-4-stimulated periostin induction was suppressed by MAP kinase/ERK kinase 1 inhibitor, indicating an involvement of the MAP kinase pathway. Pathologically, IL-4 was transcriptionally elevated in recurrent pterygia tissue and was localized to perivascular tissues and endothelial cells in the stroma of the subconjunctiva of pterygia. CONCLUSIONS Periostin is induced by IL-4 and is involved in the fibronectin-mediated pterygia fibroblast adhesion. These findings indicate that periostin probably promotes the recurrence of pterygia.

Corneal endothelial cells activate innate and acquired arm of anti-viral responses after cytomegalovirus infection

ABSTRACT Infection of the corneal endothelial cells by human cytomegalovirus (CMV) is an important cause of corneal endotheliitis. CMV endotheliitis is difficult to completely cure and relapses are frequent. This can cause blinding corneal bullous keratopathy. However, the pathogenesis of CMV endotheliitis remains undetermined. To understand the immunopathology of endotheliitis, we examined how corneal endothelial cells prime the anti‐viral immunity after CMV infection based on global transcriptional responses. To accomplish this, human corneal endothelial (HCEn) cells were infected with CMV, and the global transcriptional responses were determined by microarray analyses for primary anti‐viral responses using network analysis. Real‐time reverse transcriptase‐polymerase chain reaction (RT‐PCR) and protein array analyses were used to examine whether anti‐viral cytokines were induced, i.e., to determine whether innate immune responses were activated. To examine whether priming of acquired immune response was activated, CMV‐infected HCEn cells were co‐cultured with allogeneic CD8+ T cells from CMV seropositive donors and tested for priming activity for the CD8+ effector T cells by measuring interferon‐&ggr; secretion. The CMV‐induced responses of HCEn cells were characterized by type I interferon and pattern recognition receptor pathways which represent innate immune priming. The global transcriptional activation was specifically associated with antigen presentation with the antimicrobial response functions. Protein array analyses indicated a significant increase in the secretion of anti‐viral inflammatory cytokines including CXCL10 as innate immune responses. When HCEn cells were examined to determine whether CMV infection activated anti‐viral acquired immunity, CMV‐infected HCEn cells directly stimulated the proliferation of CD8+ T cells from CMV‐seropositive donors, and pp65 viral epitope induced interferon‐&ggr; secretion from the CD8+ T cells. We conclude that CMV‐infected HCEn cells induce innate immune priming along with provisions of acquired immune priming of CD8+ effector T cells. This information should help in the development of useful diagnostic procedures and efficacious therapeutic strategy to treat refractory corneal endotheliitis. HIGHLIGHTSCorneal endothelial cells initiate innate immune response after CMV infection.Transcriptional profiling indicates antigen presenting function.CMV‐infected‐corneal endothelial cells activate cytotoxic T lymphocytes.

Efficacy of herpes virus helicase-primase inhibitor, ASP2151, for treating herpes simplex keratitis in mouse model

Aims To determine the efficacy of a new helicase-primase inhibitor, ASP2151, for treating herpetic keratitis. Methods Murine corneas were infected with herpes simplex virus type 1 (HSV-1). ASP2151 was administered orally or topically, and the severity of epithelial dendritic keratitis was determined. The effectiveness of ASP2151 was compared with that of acyclovir and valacyclovir. The reduction of the amount of HSV in tears, enucleated eyes and trigeminal ganglia was determined by real-time PCR or plaque assay. Results Orally administered ASP2151 reduced the epithelial keratitis score significantly more than that of the vehicle-treated group (p<0.01). It also lowered the HSV-DNA levels in the tears significantly more than that by valacyclovir (p<0.01). ASP2151 ointment resulted in the same reduction of the keratitis score as acyclovir ointment, and lowered the HSV DNA in tears more than acyclovir ointment. Topical instillation of ASP2151 improved the herpetic dendritic keratitis score significantly and reduced the titre of HSV DNA in the tears in a dose-responsive way. Conclusions ASP2151 had significantly better anti-HSV activity against herpes simplex keratitis than valacyclovir and acyclovir after systemic or topical use. These findings indicate that ASP2151 should be considered as an alternative treatment for herpes simplex keratitis.