70 research outputs found
Conjunctival Lymphatic Response to Corneal Inflammation in Mice
Due to its unique characteristics, the cornea has been widely used for vascular research. However, it has never been studied whether lymphatic vessels in the conjunctiva, its neighboring tissue, are affected by corneal lymphangiogenesis (LG). The purpose of this study was to investigate whether the distribution pattern of conjunctival lymphatic vessels changes during LG using a standardized two-suture placement model. Our data from immunofluorescent microscopic studies demonstrate, for the first time, that conjunctival lymphatic vessels were more distributed in the nasal side under both normal and inflamed conditions. Additionally, under the inflamed condition, conjunctival lymphatic vessels showed a higher density and more branching points, indicating that LG occurs in the conjunctiva in response to corneal inflammation. This study not only provides novel insights into lymphatic events in the ocular surface but also offers new guidelines for developing therapeutic strategies to treat lymphatic diseases at related sites
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Characterization of Effector T Cells in Dry Eye Disease
purpose. Dry eye disease (DED) is associated with ocular surface inflammation that is thought to be mediated primarily by CD4 T cells. The purpose of this study was to investigate whether this T cell–mediated immune response is generated in the lymphoid compartment and to characterize the functional phenotype of the T cells activated in DED.
methods. DED was induced in female C57BL/6 mice by exposure to a desiccating environment in the controlled environment chamber and to systemic scopolamine. T cells from regional draining lymph nodes (LNs) of DED mice and normally sighted mice were analyzed for surface activation markers (CD69 and CD154), chemokine and cytokine receptors, and proliferation potential.
results. Draining LNs of DED mice showed increased frequencies of CD69- and CD154-expressing T cells with higher proliferative capacity. In addition, these LN T cells primarily showed a helper T-cell (Th)1 phenotype, expressing significantly higher levels of IFN-γ and IL-12Rβ2 but not IL-4R. Similarly, the LNs of DED mice showed significantly increased frequencies of T cells expressing CXCR3 and CCR5, but not CCR4, suggesting a bias toward a Th1 phenotype.
conclusions. These data demonstrate that a Th1-type immune response is induced in the regional LNs of DED mice. The identification of specific cytokine/chemokine receptors overexpressed by these T cells may signify potential novel targets/strategies for the treatment of DED
Novel Characterization of Lymphatic Valve Formation during Corneal Inflammation
Lymphatic research has progressed rapidly in recent years. Though lymphatic dysfunction has been found in a wide array of disorders from transplant rejection to cancer metastasis, to date, there is still little effective treatment for lymphatic diseases. The cornea offers an optimal site for lymphatic research due to its accessible location, transparent nature, and lymphatic-free but inducible features. However, it still remains unknown whether lymphatic valves exist in newly formed lymphatic vessels in the cornea, and how this relates to an inflammatory response. In this study, we provide the first evidence showing that lymphatic valves were formed in mouse cornea during suture-induced inflammation with the up-regulation of integrin alpha 9. The number of corneal valves increased with the progression of inflammatory lymphangiogenesis. Moreover, we have detected lymphatic valves at various developmental stages, from incomplete to more developed ones. In addition to defining the average diameter of lymphatic vessels equipped with lymphatic valves, we also report that lymphatic valves were more often located near the branching points. Taken together, these novel findings not only provide new insights into corneal lymphatic formation and maturation, but also identify a new model for future investigation on lymphatic valve formation and possibly therapeutic intervention
. DS-70, a novel and potent \uf0614 integrin antagonist, is an effective treatment for experimental allergic conjunctivitis in guinea pigs
BACKGROUND AND PURPOSE
Allergic conjunctivitis is an eye inflammation that involves the infiltration of immune cells into the conjunctiva via cell surfaceadhesion
receptors, such as integrin \u3b14\u3b21. These receptors interact with adhesion molecules expressed on the conjunctival
endothelium and may be a target to treat this disease. We synthesized DS-70, a novel \u3b1/\u3b2-peptidomimetic \u3b14 integrin antagonist,
to prevent the conjunctival infiltration of immune cells and clinical symptoms in a model of allergic conjunctivitis.
EXPERIMENTAL APPROACH
In vitro, DS-70 was pharmacologically characterized using a scintillation proximity procedure to measure its affinity for \u3b14\u3b21
integrin, and its effect on cell adhesion mediated by different integrins was also evaluated. The effects of DS-70 on vascular cell
adhesion molecule-1 (VCAM-1)-mediated degranulation of a human mast cell line and an eosinophilic cell line, which both
express \u3b14\u3b21, and on VCAM-1-mediated phosphorylation of ERK 1/2 in Jurkat E6.1 cells were investigated. Effects of DS-70
administered in the conjunctival fornix of ovalbumin-sensitized guinea pigs were evaluated.
KEY RESULTS
DS-70 bound to integrin \u3b14\u3b21 with nanomolar affinity, prevented the adhesion of \u3b14 integrin-expressing cells, antagonized VCAM-1-
mediated degranulation of mast cells and eosinophils and ERK 1/2 phosphorylation. Only 20% was degraded after an 8 h incubation
with serum. DS-70 dose-dependently reduced the clinical symptoms of allergic conjunctivitis, conjunctival \u3b14 integrin expression
and conjunctival levels of chemokines and cytokines in ovalbumin-sensitized guinea pigs.
CONCLUSIONS AND IMPLICATIONS
These findings highlight the role of \u3b14 integrin in allergic conjunctivitis and suggest that DS-70 is a potential treatment for this
condition
Disruption of TGF-β Signaling Improves Ocular Surface Epithelial Disease in Experimental Autoimmune Keratoconjunctivitis Sicca
TGF-β is a pleiotropic cytokine that can have pro- or anti-inflammatory effects depending on the context. Elevated levels of bioactive TGF-β1 in tears and elevated TGF-β1mRNA transcripts in conjunctiva and minor salivary glands of human Sjögren's Syndrome patients has also been reported. The purpose of this study was to evaluate the response to desiccating stress (DS), an experimental model of dry eye, in dominant-negative TGF-β type II receptor (CD4-DNTGFβRII) mice. These mice have a truncated TGF-β receptor in CD4(+) T cells, rendering them unresponsive to TGF-β.DS was induced by subcutaneous injection of scopolamine and exposure to a drafty low humidity environment in CD4-DNTGFβRII and wild-type (WT) mice, aged 14 weeks, for 5 days. Nonstressed (NS) mice served as controls. Parameters of ocular surface disease included corneal smoothness, corneal barrier function and conjunctival goblet cell density. NS CD4-DNTGFβRII at 14 weeks of age mice exhibited a spontaneous dry eye phenotype; however, DS improved their corneal barrier function and corneal surface irregularity, increased their number of PAS+ GC, and lowered CD4(+) T cell infiltration in conjunctiva. In contrast to WT, CD4-DNTGFβRII mice did not generate a Th-17 and Th-1 response, and they failed to upregulate MMP-9, IL-23, IL-17A, RORγT, IFN-γ and T-bet mRNA transcripts in conjunctiva. RAG1KO recipients of adoptively transferred CD4+T cells isolated from DS5 CD4-DNTGFβRII showed milder dry eye phenotype and less conjunctival inflammation than recipients of WT control.Our results showed that disruption of TGF-β signaling in CD4(+) T cells causes paradoxical improvement of dry eye disease in mice subjected to desiccating stress
Erreurs diagnostiques en médecine d'urgence (étude rétrospective de 50 dossiers d'erreurs diagnostiques au Service d'accueil des urgences du CHU de Toulouse-Purpan)
TOULOUSE3-BU Santé-Centrale (315552105) / SudocTOULOUSE3-BU Santé-Allées (315552109) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Differential distribution of blood and lymphatic vessels in the murine cornea. Invest Ophthalmol Vis Sci. 2010;51(5):2436-40. Rev Bras Oftalmol. 2015; 74 (1): 24-9 The main findings in histopathological examination of human corneal buttons with lymphangio
PURPOSE. Because of its unique characteristics, the cornea has been widely used for blood and lymphatic vessel research. However, whether limbal or corneal vessels are evenly distributed under normal or inflamed conditions has never been studied. The purpose of this study was to investigate this question and to examine whether and how the distribution patterns change during corneal inflammatory lymphangiogenesis (LG) and hemangiogenesis (HG). METHODS. Corneal inflammatory LG and HG were induced in two most commonly used mouse strains, BALB/c and C57BL/6 (6 -8 weeks of age), by a standardized two-suture placement model. Oriented flat-mount corneas together with the limbal tissues were used for immunofluorescence microscope studies. Blood and lymphatic vessels under normal and inflamed conditions were analyzed and quantified to compare their distributions. RESULTS. The data demonstrate, for the first time, greater distribution of both blood and lymphatic vessels in the nasal side in normal murine limbal areas. This nasal-dominant pattern was maintained during corneal inflammatory LG, whereas it was lost for HG. CONCLUSIONS. Blood and lymphatic vessels are not evenly distributed in normal limbal areas. Furthermore, corneal LG and HG respond differently to inflammatory stimuli. These new findings will shed some light on corneal physiology and pathogenesis and on the development of experimental models and therapeutic strategies for corneal diseases. (Invest Ophthalmol Vis Sci
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