Panton–Valentine Leukocidin Colocalizes with Retinal Ganglion and Amacrine Cells and Activates Glial Reactions and Microglial Apoptosis

International audienceExperimental models have established Panton-Valentine leukocidin (PVL) as a potential critical virulence factor during Staphylococcus aureus endophthalmitis. In the present study, we aimed to identify retinal cell targets for PVL and to analyze early retinal changes during infection. After the intravitreous injection of PVL, adult rabbits were euthanized at different time points (30 min, 1, 2, 4 and 8 h). PVL location in the retina, expression of its binding receptor C5a receptor (C5aR), and changes in Müller and microglial cells were analyzed using immunohistochemistry, Western blotting and RT-qPCR. In this model of PVL eye intoxication, only retinal ganglion cells (RGCs) expressed C5aR, and PVL was identified on the surface of two kinds of retinal neural cells. PVL-linked fluorescence increased in RGCs over time, reaching 98% of all RGCs 2 h after PVL injection. However, displaced amacrine cells (DACs) transiently colocalized with PVL. Müller and microglial cells were increasingly activated after injection over time. IL-6 expression in retina increased and some microglial cells underwent apoptosis 4 h and 8 h after PVL infection, probably because of abnormal nitrotyrosine production in the retina

IA et données de santé : regards croisés sur les droits, devoirs et responsabilités des personnes publiques

National audienc

Cytokine Profiles in Toxoplasmic and Viral Uveitis

BackgroundUveitis is a major cause of visual impairment throughout the world. Analysis of cytokine profiles in aqueous humor specimens may provide insight into the physiopathological processes that underly retinal damage in this context MethodsUsing a multiplex assay, we determined the concentrations of 17 cytokines and chemokines in aqueous humor specimens obtained from patients with ocular toxoplasmosis or viral uveitis and compared these concentrations with those in specimens obtained from patients with noninfectious intermediate uveitis or cataract ResultsFive mediators (interleukin [IL]-8, monocyte chemoattractant protein-1, tumor necrosis factor-α, IL-4, and IL-10) were detected in >50% of patients in all groups. In contrast, IL-5 and IL-12 were specific for ocular toxoplasmosis, and granulocyte monocyte colony-stimulating factor and IL-1 were specific for viral uveitis; these mediators could present specific markers for diagnostic purposes. Interferon-γ, IL-6, and macrophage inflammatory protein-1β were common markers of ocular toxoplasmosis and viral uveitis. IL-17 was a common marker of ocular toxoplasmosis and intermediate uveitis ConclusionsWe found specific cytokine profiles for each type of uveitis, with large interindividual variations and no etiological or clinical correlations. Ocular cytokine mapping contributes to a better understanding of the physiopathology of specific forms of uveitis and provides guidance for new targeted treatmen

Etude prospective des facteurs de stress lors de la chirurgie de cataracte

STRASBOURG-Medecine (674822101) / SudocSudocFranceF

EFFETS DES CORTICOIDES ET DE LA NEUROTENSINE SUR LA CICATRISATION CORNEENNE

PARIS-BIUSJ-Physique recherche (751052113) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

Le kératocône (analyse des liens avec frottement oculaire, atopie, floppy eyelid syndrome, sommeil et recherche de facteurs de risque prédictifs)

STRASBOURG-Medecine (674822101) / SudocSudocFranceF

Etude prospective randomisée de non-infériorité du traitement par azithromycine per os sur la doxycycline per os chez les patients présentant une blépharite postérieure liée à un dysfonctionnement des glandes de Meibomius modéré à sévère

STRASBOURG-Medecine (674822101) / SudocSudocFranceF

Efficacité anti-amibienne in vitro de l'association riboflavine/UV-A (365nm)

STRASBOURG-Medecine (674822101) / SudocSudocFranceF