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Peroxisomal biogenesis disorders (PBDs) are a heterogeneous group of genetic diseases. Multiple peroxisomal pathways are impaired, and very long chain fatty acids (VLCFA) are the first line biomarkers for the diagnosis. The clinical presentation of PBDs may range from severe, lethal multisystemic disorders to milder, late-onset disease. The vast majority of PBDs belong to Zellweger Spectrum Disordes (ZSDs) and represents a continuum of overlapping clinical symptoms, with Zellweger syndrome being the most severe and Heimler syndrome the less severe disease. Mild clinical conditions frequently present normal or slight biochemical alterations, making the diagnosis of these patients challenging. In the present study we used a combined WES and RNA-seq strategy to diagnose a patient presenting with retinal dystrophy as the main clinical symptom. Results showed the patient was compound heterozygous for mutations in PEX1. VLCFA were normal, but retrospective analysis of lysosphosphatidylcholines (LPC) containing C22:0–C26:0 species was altered. This simple test could avoid the diagnostic odyssey of patients with mild phenotype, such as the individual described here, who was diagnosed very late in adult life. We provide functional data in cell line models that may explain the mild phenotype of the patient by demonstrating the hypomorphic nature of a deep intronic variant altering PEX1 mRNA processing.

Spinocerebellar ataxia type 3 is an autosomal dominant neurodegenerative disorder caused by expansion of a polyglutamine (polyQ)-encoding CAG repeat in the ATXN3 gene. Because the ATXN3 protein regulates photoreceptor ciliogenesis and phagocytosis, we aimed to explore whether expanded polyQ ATXN3 impacts retinal function and integrity in SCA3 patients and transgenic mice.We evaluated the retinal structure and function in five patients with Spinocerebellar ataxia type 3 and in a transgenic mouse model of this disease (YACMJD84.2, Q84) using, respectively, optical coherence tomography (OCT) and electroretinogram (ERG). We further determined in the transgenic mice: a) the retinal expression pattern of ATXN3 and assessed the distribution of cones and rods by immunofluorescence (IF); and b) the retinal ultrastructure by transmission electron microscopy (TEM).Some patients with Spinocerebellar ataxia type 3 in our cohort revealed: i) reduced central macular thickness indirectly correlated with disease duration; ii) decreased thickness of the macula and the ganglion cell layer, and reduced macula volume inversely correlated with disease severity (SARA score); and iii) electrophysiological dysfunction of cones, rods, and inner retinal cells. Transgenic mice replicated the human OCT and ERG findings with aged homozygous Q84/Q84 mice showing a stronger phenotype accompanied by further thinning of the outer nuclear layer and photoreceptor layer and highly reduced cone and rod activities, thus supporting severe retinal dysfunction in these mice. In addition, Q84 mice showed progressive accumulation of ATXN3-positive aggregates throughout several retinal layers and depletion of cones alongside the disease course. TEM analysis of aged Q84/Q84 mouse retinas supported the IF ATXN3 aggregation findings by revealing the presence of high number of negative electron dense puncta in ganglion cells, inner plexiform and inner nuclear layers, and further showed thinning of the outer plexiform layer, thickening of the retinal pigment epithelium and elongation of apical microvilli.Our results indicate that retinal alterations detected by non-invasive eye examination using OCT and ERG could represent a biological marker of disease progression and severity in patients with Spinocerebellar ataxia type 3.

To investigate the macular and circumpapillary retinal microvasculature across all stages of Leber hereditary optic neuropathy (LHON) using swept source optical coherence tomography angiography (OCTA).This prospective, multicentre, cross-sectional, observational study analysed a total of 119 eyes of 60 patients with molecularly confirmed LHON across all stages and 120 eyes of 60 control subjects. Optical coherence tomography angiography maps centred on the fovea and optic disc were obtained to measure vessel densities (VDs) in the macular superficial (SCP) and deep (DCP) capillary plexuses, and the radial peripapillary capillary plexus (RPCP) respectively.In asymptomatic eyes, only the SCP showed significant changes on average (B coefficient = -0.72, 95% CI = -1.34 to -0.10, p = 0.022) or in sectors representing the papillomacular bundle (PMB) (B coefficient = -1.17, 95% CI = -2.23 to -0.11, p = 0.031). However, in chronic eyes, the greatest magnitude of change was found in the temporal sector of the RPCP (B coefficient = -12.36, 95% CI = -14.49 to -10.23, p 0.001). The RPCP showed the strongest correlations with visual acuity (VA, logarithm of the minimum angle of resolution; R = -0.677, p 0.001) and structural parameters (R = 0.747, p 0.001).Retinal VD changes in the circumpapillary region of the PMB appear later than in the macula but end up being more profound and correlate better with VA and structural parameters. Further studies are needed to assess the clinical utility of retinal VDs as potential LHON biomarkers.

BACKGROUND: Current treatments for several corneal lesions show limited efficacy. Here we report the clinical evaluation of the efficacy of a novel eye drop preparation produced in a public cord blood (CB) bank. MATERIALS AND METHODS: In a multicentre, retrospective, consecutive case study we evaluated 33 patients (46 eyes) unresponsive to conventional treatments who required urgent intervention. The patients were given allogeneic eye drops obtained from cord blood platelet lysate (CBED) to treat severe ocular surface lesions under a compassionate use protocol. The CBED were prepared from CB units donated for haematopoietic stem cell transplantation that did not contain the minimum stem cell dose required for this use. Patients were grouped by acute conditions (neurotrophic ulcers: group I; other corneal ulcers: group II; corneal burns: group III), and chronic conditions (ocular graft-versus-host disease: group IV; severe dry eye syndrome: group V). The patients received one or two drops of the product to the affected eye four to six times per day for 19 days. A further 19-day cycle of treatment could be repeated according to the initial clinical response. RESULTS: Patients received a median of 19 CBED vials (interquartile range 19–57, range 19–442) to complete the therapy. Group I–II–III patients showed full and partial ulcer recovery in 25 (78%) and six (19%) eyes respectively. One eye (3%) did not respond to treatment. For groups IV–V improvement was reported for 12 (85%) eyes and lesions worsened on treatment in both eyes (15%) of one patient. No severe adverse events were directly attributed to CBED. DISCUSSION: Promptly available CBED resulted in a well-tolerated allogeneic treatment that showed evidence of efficacy in this cohort of patients. These positive results support further studies on CBED from platelet lysate as a novel product of CB banks. A prospective clinical trial in neurotrophic keratitis (NCT03084861) is ongoing to confirm these preliminary data.

Proliferative diabetic retinopathy (PDR) is characterized by intraocular formation of fibroglial vascularized tissue by active vasoproliferative mechanisms. Using immunocytochemistry, we have studied changes in the distribution pattern of fibronectin (FN), laminin (LN), vitronectin (VN) and their receptors in the newly-formed capillaries of PDR. In intraocular vascularized tissue of PDR patients, FN was present on both luminal and basal surfaces of endothelial cells, and was diffusely distributed in the interpericyte space. LN was also associated with the interpericyte space. VN was occasionally detected on the luminal capillary side, but was frequent in the basal aspect of the endothelium in the interpericyte space, where it was colocalized with FN. Beta-1 subunit complex receptors were detected on the luminal side, while alpha v beta 3 integrin was identified on both sides, more so in the luminal than in the basal endothelial domain. By slot-blotting techniques and densitometric analysis, increased concentrations of intravitreous FN and VN were found in PDR in comparison with normal samples. These results suggest that FN, VN and LN have a key role in the structural arrangement of newly formed capillaries in PDR, and that receptor expression could be involved in events of endothelial cell adhesion and proliferation.

Our goal was to analyze the epidemiological and clinical findings, as well as the diagnostic approach in a group of patients in whom uveitis was the first manifestation of sarcoidosis.Retrospective study (between March 1998 and July 2002) including 31 patients diagnosed with sarcoidosis after an episode of uveitis. The group consisted of 19 females (61%) and 12 males (39%). Mean follow-up was 34.5 months. Age, sex, ocular and systemic clinical findings were recorded. Angiotensin converting enzyme (ACE) levels were measured and radiological studies of the thorax were conducted including simple radiography (Rx), computerized axial tomography (CT) and gallium scan (67Ga). Biopsy was carried out in 14 patients.Mean age was 59.6 years. Six different clinical presentations of uveitic sarcoidosis were observed, the most common being bilateral panuveitis in 13 patients (42%) and chronic anterior bilateral uveitis in 11 (35%). Gallium scan, thoracic CT and chest radiography were positive in 88%, 77% and 33% cases, respectively. ACE levels were raised in 7 of the 27 patients analyzed (26%). Histological confirmation of disease was obtained in all 14 patients biopsied with a specificity and sensitivity of 100%.Uveitis may be the presenting manifestation of sarcoidosis, especially in women over 60 years of age. Bilateral panuveitis and chronic bilateral anterior uveitis are the most common clinical presentations. The sensitivity of gallium scan and thoracic CT is greater than simple chest radiography in diagnosing pulmonary and mediastinal lesions of sarcoidosis. The need for biopsy should be individualized in each case depending on complementary exams, age and potential morbidity of the procedure.