Rod-derived Cone Viability Factor-2 is a novel bifunctional-thioredoxin-like protein with therapeutic potential

<p>Abstract</p> <p>Background</p> <p>Cone degeneration is the hallmark of the inherited retinal disease retinitis pigmentosa. We have previously identified a trophic factor "Rod-derived Cone Viability Factor (RdCVF) that is secreted by rods and promote cone viability in a mouse model of the disease.</p> <p>Results</p> <p>Here we report the bioinformatic identification and the experimental analysis of RdCVF2, a second trophic factor belonging to the Rod-derived Cone Viability Factor family. The mouse RdCVF gene is known to be bifunctional, encoding both a long thioredoxin-like isoform (RdCVF-L) and a short isoform with trophic cone photoreceptor viability activity (RdCVF-S). RdCVF2 shares many similarities with RdCVF in terms of gene structure, expression in a rod-dependent manner and protein 3D structure. Furthermore, like RdCVF, the RdCVF2 short isoform exhibits cone rescue activity that is independent of its putative thiol-oxydoreductase activity.</p> <p>Conclusion</p> <p>Taken together, these findings define a new family of bifunctional genes which are: expressed in vertebrate retina, encode trophic cone viability factors, and have major therapeutic potential for human retinal neurodegenerative diseases such as <it>retinitis pigmentosa</it>.</p

PRIMA subretinal wireless photovoltaic microchip implantation in non-human primate and feline models

Purpose To evaluate the surgical technique for subretinal implantation of two sizes of PRIMA photovoltaic wireless microchip in two animal models, and refine these surgical procedures for human trials. Methods Cats and Macaca fascicularis primates with healthy retina underwent vitrectomy surgery and were implanted with subretinal wireless photovoltaic microchip at the macula/central retina. The 1.5mm PRIMA chip was initially studied in feline eyes. PRIMA implant (2mm,1.5mm sizes) arrays were studied in primates. Feasibility of subretinal chip implantation was evaluated with a newly-developed surgical technique, with surgical complications and adverse events recorded. Results The 1.5mm implant was placed in the central retina of 11 feline eyes, with implantation duration 43-106 days. The 1.5mm implant was correctly positioned into central macula of 11 primate eyes, with follow-up periods of minimum 6 weeks (n = 11), 2 years (n = 2), and one eye for 3 years. One primate eye underwent multi-chip 1.5mm implantation using two 1.5mm chips. The 2mm implant was delivered to 4 primate eyes. Optical coherence tomography confirmed correct surgical placement of photovoltaic arrays in the subretinal space in all 26 eyes. Intraoperative complications in primate eyes included retinal tear, macular hole, retinal detachment, and vitreous hemorrhage that resolved spontaneously. Postoperatively, there was no case of significant ocular inflammation in the 1.5mm implant group. Conclusions We report subretinal implantation of 1.5mm and 2mm photovoltaic arrays in the central retina of feline and central macula of primate eyes with a low rate of device-related complications. The in vivo PRIMA implantation technique has been developed and refined for use for a 2mm PRIMA implant in ongoing human trials

EDG8/S1P5 (récepteur bi-fonctionnel de l' oligodendrocyte)

PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Néo-ovogenèse dans l’ovaire adulte: Mythe ou réalité?

National audienceFor more than a decade, the existence of ovarian stem cells that can contribute to neo-oogenesis in the adult ovary is reported by some teams, challenging the dogma according to which mammalian females are born with a fixed and non-renewed germinal cell pool. The presence of germinal stem cells with mitotic activity suggests the possibility of potential postnatal oogenesis. These cells have both germ-line and stem cell markers in culture. They have been isolated using different strategies and their ability to differentiate into oocytes has been demonstrated since after reintroduction in an ovarian somatic environment, these cells generate follicles capable of producing healthy offspring in rodents. However, many scientists remain skeptical and question the reliability of the methods used. Despite that there is no consensus on the origin of these ovarian stem cells, private companies are now proposing to use their stem cell potential to treat human infertility

Systemic and local immune responses to intraocular AAV vector administration in non-human primates

International audiencePositive clinical outcomes in adeno-associated virus (AAV)mediated retinal gene therapy have often been attributed to the low immunogenicity of AAVs and immune privilege of the eye. However, several recent studies have shown potential for inflammatory responses. The current understanding of the factors contributing to inflammation, such as the preexistence of serum antibodies against AAVs and their contribution to increases in antibody levels post-injection, is incomplete. The parameters that regulate the generation of new antibodies in response to the AAV capsid or transgene after intraocular injections are also insufficiently described. This study is a retrospective analysis of the pre-existing serum antibodies in correlation with changes in antibody levels after intraocular injections of AAV in non-human primates (NHPs) of the species Macaca fascicularis. In NHP serums, we analyzed the binding antibody (BAB) levels and a subset of these called neutralizing antibodies (NABs) that impede AAV transduction. We observed significantly higher pre-existing serum BABs against AAV8 compared with other serotypes and a dose-dependent increase in BABs and NABs in the serums collected post-injection, irrespective of the serotype or the mode of injection. Lastly, we were able to demonstrate a correlation between the serum BAB levels with clinical grading of inflammation and levels of transgene expression

Planar polarity in primate cone photoreceptors: a potential role in Stiles Crawford effect phototropism

International audienceHuman cone phototropism is a key mechanism underlying the Stiles-Crawford effect, a psychophysiological phenomenon according to which photoreceptor outer/inner segments are aligned along with the direction of incoming light. However, such photomechanical movements of photoreceptors remain elusive in mammals. We first show here that primate cone photoreceptors have a planar polarity organized radially around the optical center of the eye. This planar polarity, based on the structure of the cilium and calyceal processes, is highly reminiscent of the planar polarity of the hair cells and their kinocilium and stereocilia. Secondly, we observe under super-high resolution expansion microscopy the cytoskeleton and Usher proteins architecture in the photoreceptors, which appears to establish a mechanical continuity between the outer and inner segments. Taken together, these results suggest a comprehensive cellular mechanism consistent with an active phototropism of cones toward the optical center of the eye, and thus with the Stiles-Crawford effect

Autophagie et spermatozoïde

National audienceSpermiogenesis, the ultimate stage of spermatogenesis, is a process involving autophagy. At this stage, the acrosome is generated by vesicular fusion and most of the cytoplasm disappears. Autophagy, literally "eating oneself", allowing the elimination and replacement of proteins and nonfunctional organelles, ensures the recycling of cellular constituents and is a highly conserved cellular mechanism within eukaryotic cells. The machinery of autophagy is present in the spermatozoon, regulating the vitality and mobility of the cells. The environmental and behavioral impact on autophagy and the consequences on spermatogenesis are beginning to be studied. The purpose of this review is to synthesize current knowledge about autophagy in the mature male gamete

Noninvasive gene delivery to foveal cones for vision restoration

International audienceIntraocular injection of adeno-associated viral (AAV) vectors has been an evident route for delivering gene drugs into the retina. However, gaps in our understanding of AAV transduction patterns within the anatomically unique environments of the subretinal and intravitreal space of the primate eye impeded the establishment of noninvasive and efficient gene delivery to foveal cones in the clinic. Here, we establish new vector-promoter combinations to overcome the limitations associated with AAV-mediated cone transduction in the fovea with supporting studies in mouse models, human induced pluripotent stem cell–derived organoids, postmortem human retinal explants, and living macaques. We show that an AAV9 variant provides efficient foveal cone transduction when injected into the subretinal space several millimeters away from the fovea, without detaching this delicate region. An engineered AAV2 variant provides gene delivery to foveal cones with a well-tolerated dose administered intravitreally. Both delivery modalities rely on a cone-specific promoter and result in high-level transgene expression compatible with optogenetic vision restoration. The model systems described here provide insight into the behavior of AAV vectors across species to obtain safety and efficacy needed for gene therapy in neurodegenerative disorders

Caractérisation, compréhension des mécanismes d’altération et conservation des laques asiatiques issues de contexte archéologique et muséal

International audienceAsian lacquer is an exceptionally unique natural biomaterial. French museums host a large number of lacquered objects, originating from numerous importations from Asia, from the end of the fifteenth century. Despite the occurrence of lacquerwares in French museum collections, an insufficient amount of studies have been carried on them out up to now. Their specificity, their heritage characteristics and their conservation are little investigated and poorly known. This research project enables to develop an analytical methodology to identify biomolecular markers of vegetal species from which lacquers are harvested, correlate them to their geographic provenance and so trace a part of the history of lacquered objects. It also deals with the study of interaction of lacquers with their environment in order to determinate the factors from which they have to be protected. In fact, Asian lacquer wares are subject to damages due to poor environmental conditions (temperature, humidity). These problems of lacquer conservation are the most frequent one found in the West, since climate conditions are different than in Asia. This project leads to the proposition of visual and physico-chemical criteria of Asian lacquer alteration, at the muti-scale and from the earliest levels of damages.Matériau d'exception, la laque asiatique est un biomatériau naturel étonnant et unique. Les musées français regorgent d'objets laqués, à la suite de nombreuses importations depuis l'Asie, dès la fin du XV e siècle. Malgré l'occurrence des laques asiatiques dans les collections muséales françaises, très peu d'études ont été menées jusqu'à présent sur ces objets. Leurs spécificités, leur dimension patrimoniale et leur conservation restent peu investi-guées et mal connues. Ce projet de recherche a permis de développer une méthodologie analytique pour identifier des marqueurs biomoléculaires des espèces végétales productrices de la laque, de corréler celles-ci à leur provenance géographique et de retracer ainsi une partie de l'histoire des objets laqués. Il s'est également attaché à étudier l'interaction des laques avec leur environnement, afin de déterminer les mécanismes d'altération et les facteurs contre lesquels elles doivent être protégées. En effet, les objets laqués se dégradent sous l'effet de conditions environnementales inadaptées (température, humidité). Ces problèmes de conservation des laques se posent d'autant plus en Occident, où les conditions climatiques sont différentes de celles existant en Asie. Ce projet a conduit à la proposition de critères multi-échelles de reconnaissance visuelle et physico-chimique de l'altération de laques asiatiques, dès les premiers stades