Experimental infection of sheep, goats and cattle with a bluetongue virus serotype 4 field strain from Bulgaria, 2014.

In 2014, a new bluetongue virus serotype 4 (BTV-4) strain was detected in southern Greece and spread rapidly throughout the Balkan Peninsula and adjacent countries. Within half a year, more than 7,068 outbreaks were reported in ruminants, particularly in sheep. However, the reported morbidity and case fatality rates in ruminants varied. The pathogenesis of a Bulgarian BTV-4 strain isolated from sheep during the BTV-4 epizootic was studied in different species. Therefore, four sheep, three goats and three cattle were experimentally infected with the isolate BTV-4/BUL2014/15 and monitored for clinical signs up to several weeks. Serum and whole-blood samples were collected at regular intervals and subjected to serological and virological analyses. In this context, BTV-4-specific real-time RT-PCR assays were developed. The infection kinetics were similar to those known for other traditional BTV serotypes, and only mild BT-like clinical signs were observed in goats and sheep. In cattle, no obvious clinical signs were observed, except a transient increase in body temperature. The study results contrast with the severe clinical signs reported in sheep experimentally infected with an African BTV-4 strain and with the reports of BT-like clinical signs in a considerable proportion of different ruminant species infected with BTV-4 in the Balkan region and Italy. The discrepancies between the results of these animal trials and observations of BTV-4 infection in the field may be explained by the influence of various factors on the manifestation of BT disease, such as animal breed, fitness and virus strain, as described previously.

Bluetongue virus infection in naïve cattle: Identification of circulating serotypes and associated Culicoides biting midge species in Trinidad.

To better understand risks associated with trading cattle, it is important to know which serotypes of Bluetongue virus (BTV) are circulating within the exporting and importing country. Hence, this study was conducted to identify the circulating serotypes of BTV in Trinidad. Blood samples were collected monthly from sixty BTV- naïve imported cattle over a six month period after their arrival in the country. Virological (PCR and virus isolation) and serological (ELISA) analyses were carried out on the samples and CDC light traps were placed near the cattle enclosure to trap and identify the species of Culicoides biting midges that were present. All of the cattle seroconverted for BTV antibodies within three months of their arrival in the country and real-time reverse transcription PCR (rRT-PCR) detected BTV-RNA in the samples throughout the remainder of the study. The patterns of infection observed in the cattle indicated serial infections with multiple serotypes. A combination of BTV serotype-specific rRT-PCR on the original blood samples and virus isolation followed by serotype-specific rRT-PCR on selected samples, confirmed the presence of BTV serotypes 1, 2, 3, 5, 12 and 17. This is the first report of BTV-2 and BTV-5 in Trinidad. Light-suction traps placed in close proximity to the cattle predominantly trapped Culicoides insignis Lutz 1913 species (96%), with a further six Culicoides species making up the remaining 4% of trapped samples. The circulation of multiple BTV serotypes in Trinidad underlines the need for regular surveillance, which will contribute to the development of risk assessments for trade in livestock.

Tropism of engineered and evolved recombinant AAV serotypes in the rd1 mouse and ex vivo primate retina.

There is much debate on the adeno-associated virus (AAV) serotype that best targets specific retinal cell types and the route of surgical delivery-intravitreal or subretinal. This study compared three of the most efficacious AAV vectors known to date in a mouse model of retinal degeneration (rd1 mouse) and macaque and human retinal explants. Green fluorescent protein (GFP) driven by a ubiquitous promoter was packaged into three AAV capsids: AAV2/8(Y733F), AAV2/2(quad Y-F) and AAV2/2(7m8). Overall, AAV2/2(7m8) transduced the largest area of retina and resulted in the highest level of GFP expression, followed by AAV2/2(quad Y-F) and AAV2/8(Y733F). AAV2/2(7m8) and AAV2/2(quad Y-F) both resulted in similar patterns of transduction whether they were injected intravitreally or subretinally. AAV2/8(Y733F) transduced a significantly smaller area of retina when injected intravitreally compared with subretinally. Retinal ganglion cells, horizontal cells and retinal pigment epithelium expressed relatively high levels of GFP in the mouse retina, whereas amacrine cells expressed low levels of GFP and bipolar cells were infrequently transduced. Cone cells were the most frequently transduced cell type in macaque retina explants, whereas Müller cells were the predominant transduced cell type in human retinal explants. Of the AAV serotypes tested, AAV2/2(7m8) was the most effective at transducing a range of cell types in degenerate mouse retina and macaque and human retinal explants.

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Assay for the Rapid Detection of African Horse Sickness Virus.

African horse sickness (AHS) is a disease of equids caused by African Horse Sickness Virus (AHSV) and is transmitted by Culicoides midges. AHS is endemic in sub-Saharan Africa, but during the past century, outbreaks of significant economic importance and elevated mortality have been recorded in Northern African countries, the Iberian and Arabian Peninsula, the Middle East and the Indian subcontinent. Effective control combines the application of early warning systems, accurate laboratory diagnosis and reporting, animal movement restrictions, suitable vaccination and surveillance programs, and the coordination of all these measures by efficient veterinary services. Conventional reverse-transcriptase (RT) PCR (RT-PCR) and real-time RT-PCR (rRT-PCR) assays have improved the sensitivity and rapidity of diagnosing AHS, resulting in the adoption of these methods as recommended tests by the World Organisation for Animal Health (OIE). However, currently these assays are only performed within laboratory settings; therefore, the development of field diagnostics for AHS would improve the fast implementation of control policies. Loop-mediated isothermal amplification (LAMP) is an isothermal, autocycling, strand-displacement nucleic acid amplification technique which can be performed in the field. LAMP assays are attractive molecular assays because they are simple to use, rapid, portable and have sensitivity and specificity within the range of rRT-PCR. This study describes the development of a novel RT-LAMP assay for the detection of AHSV. The AHSV RT-LAMP assay has an analytical sensitivity of 96.1% when considering an rRT-PCR cut-off value of CT  > 36, or 91.3% when no rRT-PCR cut-off is applied. Diagnostic sensitivity and specificity were 100%. This assay provides for a rapid and low cost AHS diagnostic for use in the field.

Antibody neutralization poses a barrier to intravitreal adeno-associated viral vector gene delivery to non-human primates.

Gene delivery vectors based on adeno-associated viruses (AAV) have exhibited promise in both preclinical disease models and human clinical trials for numerous disease targets, including the retinal degenerative disorders Leber's congenital amaurosis and choroideremia. One general challenge for AAV is that preexisting immunity, as well as subsequent development of immunity following vector administration, can severely inhibit systemic AAV vector gene delivery. However, the role of neutralizing antibodies (NABs) in AAV transduction of tissues considered to be immune privileged, such as the eye, is unclear in large animals. Intravitreal AAV administration allows for broad retinal delivery, but is more susceptible to interactions with the immune system than subretinal administration. To assess the effects of systemic anti-AAV antibody levels on intravitreal gene delivery, we quantified the anti-AAV antibodies present in sera from non-human primates before and after intravitreal injections with various AAV capsids. Analysis showed that intravitreal administration resulted in an increase in anti-AAV antibodies regardless of the capsid serotype, transgene or dosage of virus injected. For monkeys injected with wild-type AAV2 and/or an AAV2 mutant, the variable that most significantly affected the production of anti-AAV2 antibodies was the amount of virus delivered. In addition, post-injection antibody titers were highest against the serotype administered, but the antibodies were also cross-reactive against other AAV serotypes. Furthermore, NAB levels in serum correlated with those in vitreal fluid, demonstrating both that this route of administration exposes AAV capsid epitopes to the adaptive immune system and that serum measurements are predictive of vitreous fluid NAB titers. Moreover, the presence of preexisting NAB titers in the serum of monkeys correlated strongly (R=0.76) with weak, decaying or no transgene expression following intravitreal administration of AAV. Investigating anti-AAV antibody development will aid in understanding the interactions between gene therapy vectors and the immune system during ocular administration and can form a basis for future clinical studies applying intravitreal gene delivery.

Effectiveness of cooking to reduce norovirus and infectious F-specific RNA bacteriophage concentrations in Mytilus edulis.

AIMS: The aim of this study was to determine if domestic cooking practices can reduce concentrations of norovirus (NoV) and F-specific RNA (FRNA) bacteriophage in experimentally contaminated mussels. METHODS AND RESULTS: Mussels (n = 600) contaminated with NoV and FRNA bacteriophage underwent four different cooking experiments performed in triplicate at ~70°C and >90°C. Concentrations of infectious FRNA bacteriophage (using a plaque assay) were compared with concentrations of FRNA bacteriophage and NoV determined using a standardised RT-qPCR. Initial concentrations of infectious FRNA bacteriophage (7·05 log10  PFU g(-1) ) in mussels were not significantly reduced in simmering water (~70°C); however, cooking at higher temperatures (>90°C) reduced infectious FRNA bacteriophage to undetected levels within 3 min. Further investigation determined the time required for a 1-log reduction of infectious FRNA bacteriophage at 90°C to be 42 s therefore a >3-log reduction in infectious virus can be obtained by heating mussel digestive tissue to 90°C for 126 s. CONCLUSIONS: Domestic cooking practices based on shell opening alone do not inactivate infectious virus in mussels, however, cooking mussels at high temperatures is effective to reduce infectious virus concentrations and the risk of illness in consumers. SIGNIFICANCE AND IMPACT OF THE STUDY: The data will contribute towards evidence-based cooking recommendations for shellfish to provide a safe product for human consumption.

Retinoschisin gene therapy in photoreceptors, Müller glia or all retinal cells in the Rs1h-/- mouse.

X-linked retinoschisis, a disease characterized by splitting of the retina, is caused by mutations in the retinoschisin gene, which encodes a putative secreted cell adhesion protein. Currently, there is no effective treatment for retinoschisis, though viral vector-mediated gene replacement therapies offer promise. We used intravitreal delivery of three different AAV vectors to target delivery of the RS1 gene to Müller glia, photoreceptors or multiple cell types throughout the retina. Müller glia radially span the entire retina, are accessible from the vitreous, and remain intact throughout progression of the disease. However, photoreceptors, not glia, normally secrete retinoschisin. We compared the efficacy of rescue mediated by retinoschisin secretion from these specific subtypes of retinal cells in the Rs1h-/- mouse model of retinoschisis. Our results indicate that all three vectors deliver the RS1 gene, and that several cell types can secrete retinoschisin, leading to transport of the protein across the retina. The greatest long-term rescue was observed when photoreceptors produce retinoschisin. Similar rescue was observed with photoreceptor-specific or generalized expression, although photoreceptor secretion may contribute to rescue in the latter case. These results collectively point to the importance of cell targeting and appropriate vector choice in the success of retinal gene therapies.

Norovirus genotypes implicated in two oyster-related illness outbreaks in Ireland.

We investigated norovirus (NoV) concentrations and genotypes in oyster and faecal samples associated with two separate oyster-related outbreaks of gastroenteritis in Ireland. Quantitative analysis was performed using real-time quantitative reverse transcription polymerase chain reaction and phylogenetic analysis was conducted to establish the NoV genotypes present. For both outbreaks, the NoV concentration in oysters was >1000 genome copies/g digestive tissue and multiple genotypes were identified. In faecal samples, GII.13 was the only genotype detected for outbreak 1, whereas multiple genotypes were detected in outbreak 2 following the application of cloning procedures. While various genotypes were identified in oyster samples, not all were successful in causing infection in consumers. In outbreak 2 NoV GII.1 was identified in all four faecal samples analysed and NoV GII concentrations in faecal samples were >108 copies/g. This study demonstrates that a range of NoV genotypes can be present in highly contaminated oysters responsible for gastroenteritis outbreaks.

Highly enhanced Raman scattering of graphene using plasmonic nano-structure.

Highly enhanced Raman scattering of graphene on a plasmonic nano-structure platform is demonstrated. The plasmonic platform consists of silver nano-structures in a periodic array on top of a gold mirror. The gold mirror is used to move the hot spot to the top surface of the silver nano-structures, where the graphene is located. Two different nano-structures, ring and crescent, are studied. The actual Raman intensity is enhanced by a factor of 890 for the G-peak of graphene on crescents as compared to graphene on a silicon dioxide surface. The highest enhancement is observed for the G-peak as compared to the 2D-peak. The results are quantitatively well-matched with a theoretical model using an overlap integral of incident electric field intensities with the corresponding intensities of Raman signals at the G- and 2D-peaks. The interaction of light with nano-structures is simulated using finite element method (FEM).

Misguidance and modulation of axonal regeneration by Stat3 and Rho/ROCK signaling in the transparent optic nerve.

The use of the visual system played a major role in the elucidation of molecular mechanisms controlling axonal regeneration in the injured CNS after trauma. In this model, CNTF was shown to be the most potent known neurotrophic factor for axonal regeneration in the injured optic nerve. To clarify the role of the downstream growth regulator Stat3, we analyzed axonal regeneration and neuronal survival after an optic nerve crush in adult mice. The infection of retinal ganglion cells with adeno-associated virus serotype 2 (AAV2) containing wild-type (Stat3-wt) or constitutively active (Stat3-ca) Stat3 cDNA promoted axonal regeneration in the injured optic nerve. Axonal growth was analyzed in whole-mounted optic nerves in three dimensions (3D) after tissue clearing. Surprisingly, with AAV2.Stat3-ca stimulation, axons elongating beyond the lesion site displayed very irregular courses, including frequent U-turns, suggesting massive directionality and guidance problems. The pharmacological blockade of ROCK, a key signaling component for myelin-associated growth inhibitors, reduced axonal U-turns and potentiated AAV2.Stat3-ca-induced regeneration. Similar results were obtained after the sustained delivery of CNTF in the axotomized retina. These results show the important role of Stat3 in the activation of the neuronal growth program for regeneration, and they reveal that axonal misguidance is a key limiting factor that can affect long-distance regeneration and target interaction after trauma in the CNS. The correction of axonal misguidance was associated with improved long-distance axon regeneration in the injured adult CNS.

Simulated sunlight inactivation of norovirus and FRNA bacteriophage in seawater.

AIMS: To investigate norovirus (NoV) and F-specific RNA (FRNA) bacteriophage inactivation in seawater under simulated sunlight and temperature conditions representative of summer (235 W m(-2) ; 17°C) and winter (56 W m(-2) ; 10°C) conditions in Ireland. METHODS AND RESULTS: Inactivation experiments were carried out using a collimated beam of simulated sunlight and 100 ml of filtered seawater seeded with virus under controlled temperature conditions. NoV concentrations were determined using RT-qPCR, and FRNA bacteriophage concentrations were determined using RT-qPCR and by plaque assay. For all virus types, the fluence required to achieve a 90% reduction in detectable viruses (S90 value) using RT-qPCR was not significantly different between summer and winter conditions. S90 values for FRNA bacteriophage determined by plaque assay were significantly less than those determined by RT-qPCR. Unlike S90 values determined by RT-qPCR, a significant difference existed between summer and winter S90 values for infectious FRNA bacteriophage. CONCLUSIONS: This study demonstrated that RT-qPCR significantly overestimates the survival of infectious virus and is therefore unsuitable for determining the inactivation rates of viruses in seawater. SIGNIFICANCE AND IMPACT OF THE STUDY: Results from this study provide initial data on the inactivation of NoV and FRNA bacteriophage in seawater under representative summer and winter conditions and will be of interest to shellfish and water management agencies alike.

Reduced nucleus accumbens reactivity and adolescent depression following early-life stress.

Depression is a common outcome for those having experienced early-life stress (ELS). For those individuals, depression typically increases during adolescence and appears to endure into adulthood, suggesting alterations in the development of brain systems involved in depression. Developmentally, the nucleus accumbens (NAcc), a limbic structure associated with reward learning and motivation, typically undergoes dramatic functional change during adolescence; therefore, age-related changes in NAcc function may underlie increases in depression in adolescence following ELS. The current study examined the effects of ELS in 38 previously institutionalized children and adolescents in comparison to a group of 31 youths without a history of ELS. Consistent with previous research, the findings showed that depression was higher in adolescents than children with a history of ELS. Additionally, functional magnetic resonance imaging results showed atypical NAcc development, where the ELS group did not show a typical increase in NAcc reactivity during adolescence. Consequently, the ELS group showed NAcc hypoactivation during adolescence, and lower NAcc reactivity was correlated with higher depression scores. The results have important implications for understanding how ELS may influence increases in depression via neural development during the transition to adolescence and highlight the importance of identifying at-risk individuals in childhood, a potential critical period for depression-targeted intervention.

Enhanced gene delivery to the neonatal retina through systemic administration of tyrosine-mutated AAV9.

Delivery of therapeutic genes to a large region of the retina with minimal damage from intraocular surgery is a central goal of treatment for retinal degenerations. Recent studies have shown that AAV9 can reach the central nervous system (CNS) and retina when administered systemically to neonates, which is a promising strategy for some retinal diseases. We investigated whether the retinal transduction efficiency of systemically delivered AAV9 could be improved by mutating capsid surface tyrosines, previously shown to increase the infectivity of several AAV vectors. Specifically, we evaluated retinal transduction following neonatal intravascular administration of AAV9 vectors containing tyrosine to phenylalanine mutations at two highly conserved sites. Our results show that a novel, double tyrosine mutant of AAV9 significantly enhanced gene delivery to the CNS and retina, and that gene expression can be restricted to rod photoreceptor cells by incorporating a rhodopsin promoter. This approach provides a new methodology for the development of retinal gene therapies or creation of animal models of neurodegenerative disease.

Neuronal Nogo-A upregulation does not contribute to ER stress-associated apoptosis but participates in the regenerative response in the axotomized adult retina.

Nogo-A, an axonal growth inhibitory protein known to be mostly present in CNS myelin, was upregulated in retinal ganglion cells (RGCs) after optic nerve injury in adult mice. Nogo-A increased concomitantly with the endoplasmic reticulum stress (ER stress) marker C/EBP homologous protein (CHOP), but CHOP immunostaining and the apoptosis marker annexin V did not co-localize with Nogo-A in individual RGC cell bodies, suggesting that injury-induced Nogo-A upregulation is not involved in axotomy-induced cell death. Silencing Nogo-A with an adeno-associated virus serotype 2 containing a short hairpin RNA (AAV2.shRNA-Nogo-A) or Nogo-A gene ablation in knock-out (KO) animals had little effect on the lesion-induced cell stress or death. On the other hand, Nogo-A overexpression mediated by AAV2.Nogo-A exacerbated RGC cell death after injury. Strikingly, however, injury-induced sprouting of the cut axons and the expression of growth-associated molecules were markedly reduced by AAV2.shRNA-Nogo-A. The axonal growth in the optic nerve activated by the intraocular injection of the inflammatory molecule Pam3Cys tended to be lower in Nogo-A KO mice than in WT mice. Nogo-A overexpression in RGCs in vivo or in the neuronal cell line F11 in vitro promoted regeneration, demonstrating a positive, cell-autonomous role for neuronal Nogo-A in the modulation of axonal regeneration.

The trajectory of recovery and the inter-relationships of symptoms, activity and participation in the first year following total hip and knee replacement.

OBJECTIVE: Primary total hip (THR) and knee (TKR) replacement outcomes typically include pain and function with a single time of follow-up post-surgery. This research evaluated the trajectory of recovery and inter-relationships within and across time of physical impairments (PI) (e.g., symptoms), activity limitations (AL), and social participation restrictions (PR) in the year following THR and TKR for osteoarthritis. DESIGN: Participants (hip: n=437; knee: 494) completed measures pre-surgery and at 2 weeks, 1, 3, 6 and 12 months post-surgery. These included PI (Hip Disability and Osteoarthritis Outcome Score (HOOS)/Knee Injury and Osteoarthritis Outcome Score (KOOS) symptoms and Chronic Pain Grade); AL (HOOS/KOOS activities of daily living and sports/leisure activities); and, PR (Late Life Disability and the Calderdale community mobility). Repeated measures analysis of variance (RANOVA) was used to evaluate the trajectory of recovery of outcomes and the inter-relationships of PI, AL and PR were evaluated using path analysis. All analyses were adjusted for age, sex, obesity, THR/TKR, low back pain and mood. RESULTS: THR: age 31-86 years with 55% female; TKR: age 35-88 years with 65% female. Significant improvements in outcomes were observed over time. However, improvements were lagged over time with earlier improvements in PI and AL and later improvements in PR. Within and across time, PI was associated with AL and AL was associated with PR. The magnitude of these inter-relationships varied over time. CONCLUSION: Given the lagged inter-relationship of PI, AL and PR, the provision and timing of interventions targeting all constructs are critical to maximizing outcome. Current care pathways focusing on short-term follow-up with limited attention to social and community participation should be re-evaluated.

Management of health risks associated with oysters harvested from a norovirus contaminated area, Ireland, February-March 2010.

Oysters from a harvesting area responsible for outbreaks of gastroenteritis were relaid at a clean seawater site and subsequently depurated in tanks of purified seawater at elevated temperatures. This combined treatment reduced norovirus levels to those detected prior to the outbreak. On the basis of norovirus monitoring the sale of treated oysters was permitted although the harvest area remained closed for direct sale of oysters. No reports of illness have been associated with the consumption of treated oysters.

Embryonic staging series for the beach spawning, terrestrially incubating California grunion Leuresthes tenuiswith comparisons to other Atherinomorpha.

California grunion Leuresthes tenuis synchronize spawning with tidal cycles, so the embryos incubate in a terrestrial environment, delay hatching until cued by a specific environmental trigger, and may extend incubation for up to an additional four weeks. These adaptations, however, do not appear to alter the morphology or sequence of early developmental stages as compared to other Atherinomorph fishes in the Orders Beloniformes and Cyprinodontiformes. Embryonic development is described in a series of 30 stages based on morphology observed by light microscopy. Stages are placed in five periods: zygote and cleavage, blastula, gastrula, segmentation and organogenesis, and hatching competence. Embryos from a southern population of L. tenuis in Los Angeles are compared with embryos found > 560 km north in San Francisco Bay. Northern L. tenuis embryos developed more slowly at several stages than southern embryos and reached hatching competence later, but both locations maintained synchrony with the tidal cycle for both spawning and hatching. The variation in rates of development and stage at hatching readiness are forms of developmental heterochrony that may be associated with evolutionary adaptation or morphological plasticity within this highly successful clade.

Anti-clarin-1 AAV-delivered ribozyme induced apoptosis in the mouse cochlea.

Usher syndrome type 3 is caused by mutations in the USH3A gene, which encodes the protein clarin-1. Clarin-1 is a member of the tetraspanin superfamily (TM4SF) of transmembrane proteins, expressed in the organ of Corti and spiral ganglion cells of the mouse ear. We have examined whether the AAV-mediated anti-clarin ribozyme delivery causes apoptotic cell death in vivo in the organ of Corti. We used an AAV-2 vector delivered hammerhead ribozyme, AAV-CBA-Rz, which specifically recognizes and cleaves wild type mouse clarin-1 mRNA. Cochleae of CD-1 mice were injected either with 1mul of the AAV-CBA-Rz, or control AAV vectors containing the green fluorescent protein (GFP) marker gene (AAV-CBA-GFP). Additional controls were performed with saline only. At one-week and one-month post-injection, the animals were sacrificed and the cochleae were studied by histology and fluorescence imaging. Mice injected with AAV-CBA-GFP displayed GFP reporter expression of varying fluorescence intensity throughout the length of the cochlea in the outer and inner hair cells and stria vascularis, and to a lesser extent, in vestibular epithelial cells. GFP expression was not detectable in the spiral ganglion. The pro-apoptotic effect of AAV-CBA-delivered anti-clarin-1 ribozymes was evaluated by TUNEL-staining. We observed in the AAV-CBA-Rz, AAV-CBA-GFP and saline control groups apoptotic nuclei in the outer and inner hair cells and in the stria vascularis one week after the microinjection. The vestibular epithelium was also observed to contain apoptotic cells. No TUNEL-positive spiral ganglion neurons were detected. After one-month post-injection, the AAV-CBA-Rz-injected group had significantly more apoptotic outer and inner hair cells and cells of the stria vascularis than the AAV-CBA-GFP group. In this study, we demonstrate that AAV-CBA mediated clarin-1 ribozyme may induce apoptosis of the cochlear hair cells and cells of the stria vascularis. Surprisingly, we did not observe apoptosis in spiral ganglion cells, which should also be susceptible to clarin-1 mRNA cleavage. This result may be due to the injection technique, the promoter used, or tropism of the AAV serotype 2 viral vector. These results suggest the role of apoptosis in the progression of USH3A hearing loss warrants further evaluation.

Glial cell line derived neurotrophic factor delays photoreceptor degeneration in a transgenic rat model of retinitis pigmentosa.

We designed experiments to evaluate the therapeutic potential of glial cell line derived neurotrophic factor (GDNF) to rescue photoreceptors from genetically determined cell death. Gene transfer of the neurotrophic factor to the retina was achieved via a recombinant adeno-associated virus (rAAV) vector containing the chicken beta-actin promoter/immediate early cytomegalovirus enhancer (CBA) driving the human GDNF gene. We delivered AAV-CBA-GDNF to the retinas of an animal model of retinitis pigmentosa, the TgN S334ter-4 rhodopsin line of transgenic rats. Immunohistochemical studies localized AAV-CBA-GDNF-derived recombinant protein to cell bodies, inner segments, and outer segments of photoreceptor cells as well as to retinal pigment epithelial cells. We assessed the effect of viral delivery by morphometric and electroretinographic analysis. These experiments showed that GDNF vector treatment leads to increased rod photoreceptor survival as indicated by morphometric analysis of outer nuclear layer thickness. AAV-CBA-GDNF-treated retinas also demonstrated functional improvement by the substantially increased amplitude of electroretinograms. AAV-CBA-GDNF delivery had a significant rescue effect on photoreceptor degeneration in this animal model.

North Carolina macular dystrophy: clinicopathologic correlation.

PURPOSE: To describe the clinical and histopathologic findings of a 72-year-old female with North Carolina macular dystrophy. METHODS: Observational case report with histopathologic correlation. Clinical examination includes slit-lamp biomicroscopy, indirect ophthalmoscopy, color fundus photography, and focal electroretinography. Histopathologic examination of the enucleated left eye performed with light microscopy. RESULTS: Light microscopy demonstrated a discrete macular lesion characterized by focal absence of photoreceptor cells and retinal pigment epithelium with attenuation of the Bruch membrane and focal atrophy of the choriocapillaris. Adjacent to the macular lesion, some lipofuscin was identified in the retinal pigment epithelium. CONCLUSION: North Carolina macular dystrophy has both clinical and microscopic appearances of a well-demarcated lesion confined to the macula, which involves the retina, pigment epithelium, and choriocapillaris.