The N-terminal region of centrosomal protein 290 (CEP290) restores vision in a zebrafish model of human blindness

The gene coding for centrosomal protein 290 (CEP290), a large multidomain protein, is the most frequently mutated gene underlying the non-syndromic blinding disorder Leber's congenital amaurosis (LCA). CEP290 has also been implicated in several cilia-related syndromic disorders including Meckel–Gruber syndrome, Joubert syndrome, Senor–Loken syndrome and Bardet–Biedl syndrome (BBS). In this study, we characterize the developmental and functional roles of cep290 in zebrafish. An antisense oligonucleotide [Morpholino (MO)], designed to generate an altered cep290 splice product that models the most common LCA mutation, was used for gene knockdown. We show that cep290 MO-injected embryos have reduced Kupffer's vesicle size and delays in melanosome transport, two phenotypes that are observed upon knockdown of bbs genes in zebrafish. Consistent with a role in cilia function, the cep290 MO-injected embryos exhibited a curved body axis. Patients with LCA caused by mutations in CEP290 have reduced visual perception, although they present with a fully laminated retina. Similarly, the histological examination of retinas from cep290 MO-injected zebrafish revealed no gross lamination defects, yet the embryos had a statistically significant reduction in visual function. Finally, we demonstrate that the vision impairment caused by the disruption of cep290 can be rescued by expressing only the N-terminal region of the human CEP290 protein. These data reveal that a specific region of the CEP290 protein is sufficient to restore visual function and this region may be a viable gene therapy target for LCA patients with mutations in CEP290

Diagnostic techniques for inflammatory eye disease: past, present and future: a review

Investigations used to aid diagnosis and prognosticate outcomes in ocular inflammatory disorders are based on techniques that have evolved over the last two centuries have dramatically evolved with the advances in molecular biological and imaging technology. Our improved understanding of basic biological processes of infective drives of innate immunity bridging the engagement of adaptive immunity have formed techniques to tailor and develop assays, and deliver targeted treatment options. Diagnostic techniques are paramount to distinguish infective from non-infective intraocular inflammatory disease, particularly in atypical cases. The advances have enabled our ability to multiplex assay small amount of specimen quantities of intraocular samples including aqueous, vitreous or small tissue samples. Nevertheless to achieve diagnosis, techniques often require a range of assays from traditional hypersensitivity reactions and microbe specific immunoglobulin analysis to modern molecular techniques and cytokine analysis. Such approaches capitalise on the advantages of each technique, thereby improving the sensitivity and specificity of diagnoses. This review article highlights the development of laboratory diagnostic techniques for intraocular inflammatory disorders now readily available to assist in accurate identification of infective agents and appropriation of appropriate therapies as well as formulating patient stratification alongside clinical diagnoses into disease groups for clinical trials

Retinal nerve fibre layer thickness analysis in X-linked retinoschisis using Fourier-domain OCT

PURPOSE: 19 To evaluate the presence of retinal nerve fiber layer (RNFL) defects in patients with XLRS using high speed, high resolution, Fourier domain OCT (FD-OCT). METHODS: Twenty four patients with XLRS seen by the authors were enrolled in the study. All patients underwent a complete eye examination. FD-OCT was performed using Optovue technology. A quadrant of the RNFL was considered to be thinned if at least 2 of the 4 segments in the quadrant were reduced in thickness. RESULTS: The average age of the 24 patients in the study was 28.8 years ± 14.7 years. Thinning of the RNFL in 1 quadrant was seen in 10 patients (41.7%), and thinning in 2 or more quadrants was seen in 8 patients (33.3%). Thinning in the inferior quadrant was most commonly seen and was observed in 12 patients (50%), followed by the temporal quadrant in 8 patients (33.3%), nasal quadrant in 4 patients (16.7%), and the superior quadrant in 4 patients (16.7%). CONCLUSIONS: Among our 24 patients with XLRS, 15 patients (62.5%) showed a thinning of the RNFL in one or more quadrants in at least one eye and 9 patients (37.5%) in both eyes. The use of high speed, high resolution FD-OCT may be useful to determine the presence of possible changes in RNFL thickness in patients with XLRS. Reductions in RNFL thickness in such patients could be relevant in their selection for future therapeutic trials

Retinal nerve fibre layer thickness analysis in X-linked retinoschisis using Fourier-domain

PURPOSE: To evaluate the presence of retinal nerve fibre layer (RNFL) defects in patients with X-linked retinoschisis (XLRS) using high-speed, high-resolution, Fourier domain OCT (FD-OCT). METHODS: Twenty-four patients with XLRS seen by the authors were enrolled in the study. All patients underwent a complete eye examination. FD-OCT was performed using Optovue technology. A quadrant of the RNFL was considered to be thinned if at least two of the four segments in the quadrant were reduced in thickness. RESULTS: The average age of the 24 patients in the study was 28.8+/-14.7 years. Thinning of the RNFL in one quadrant was seen in 10 patients (41.7%), and thinning in two or more quadrants was seen in 8 patients (33.3%). Thinning in the inferior quadrant was most commonly seen and was observed in 12 patients (50%), followed by the temporal quadrant in 8 patients (33.3%), nasal quadrant in 4 patients (16.7%), and the superior quadrant in 4 patients (16.7%). CONCLUSIONS: Among our 24 patients with XLRS, 15 patients (62.5%) showed a thinning of the RNFL in one or more quadrants in at least one eye and 9 patients (37.5%) in both eyes. High-speed, high-resolution FD-OCT may be useful to determine the presence of possible changes in RNFL thickness in patients with XLRS. Reductions in RNFL thickness in such patients could be relevant in their selection for future therapeutic trials