Mechanistic Insights Into an Ancient Adenovirus Precursor Protein VII Show Multiple Nuclear Import Receptor Pathways.

Adenoviral pVII proteins are multifunctional, highly basic, histone-like proteins that can bind to and transport the viral genome into the host cell nucleus. Despite the identification of several nuclear localization signals (NLSs) in the pVII protein of human adenovirus (HAdV)2, the mechanistic details of nuclear transport are largely unknown. Here we provide a full characterization of the nuclear import of precursor (Pre-) pVII protein from an ancient siadenovirus, frog siadenovirus 1 (FrAdV1), using a combination of structural, functional, and biochemical approaches.

Pseudodominant inheritance of retinitis pigmentosa in a family with mutations in the Eyes Shut Homolog (EYS) gene.

Sequence variants in Eyes Shut Homolog (EYS) gene are one of the most frequent causes of autosomal recessive retinitis pigmentosa (RP). Herein, we describe an Italian RP family characterized by EYS-related pseudodominant inheritance. The female proband, her brother, and both her sons showed typical RP, with diminished or non-recordable full-field electroretinogram, narrowing of visual field, and variable losses of central vision.

Structural and functional characterization of siadenovirus core protein VII nuclear localization demonstrates the existence of multiple nuclear transport pathways.

Adenovirus protein VII (pVII) plays a crucial role in the nuclear localization of genomic DNA following viral infection and contains nuclear localization signal (NLS) sequences for the importin (IMP)-mediated nuclear import pathway. However, functional analysis of pVII in adenoviruses to date has failed to fully determine the underlying mechanisms responsible for nuclear import of pVII. Therefore, in the present study, we extended our analysis by examining the nuclear trafficking of adenovirus pVII from a non-human species, psittacine siadenovirus F (PsSiAdV).

Ocular Manifestations in Patients Affected by p63-Associated Disorders: Ectrodactyly-Ectodermal Dysplasia-Clefting (EEC) and Ankyloblepharon-Ectodermal Defects-Cleft Lip Palate (AEC) Syndromes.

Background/aims: The Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) and Ankyloblepharon-ectodermal defect-cleft lip/palate (AEC) syndromes are rare autosomal dominant diseases caused by heterozygous mutations in the p63 gene. Patients are characterized by abnormalities of the skin, teeth, and hair and have limb defects, orofacial clefting and ectodermal dysplasia. In addition, they often show ocular surface alterations, leading to progressive corneal clouding and eventually blindness.

Innovative Therapeutic Approaches for the Treatment of the Ocular Morbidities in Patients with EEC Syndrome.

Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) syndrome is caused by heterozygous missense point mutations in the gene, an important transcription factor during embryogenesis and for stem cell differentiation in stratified epithelia. Most of the cases are sporadic, related to de novo mutations arising during early-stage development. Familial cases show an autosomic dominant inheritance.

Analysis and pharmacological modulation of senescence in human epithelial stem cells.

Human epithelial stem cells (ESCs) are characterized by long-term regenerative properties, much dependent on the tissue of origin and varying during their lifespan. We analysed such variables in cultures of ESCs isolated from the skin, conjunctiva, limbus and oral mucosa of healthy donors and patients affected by ectrodactyly-ectodermal dysplasia-clefting syndrome, a rare genetic disorder caused by mutations in the p63 gene. We cultured cells until exhaustion in the presence or in the absence of DAPT (γ-secretase inhibitor; N-[N-(3, 5-difluorophenacetyl)-L-alanyl]-S-phenylglycine T-butyl ester).

New Frontiers of Corneal Gene Therapy.

Corneal diseases are among the most prevalent causes of blindness worldwide. The transparency and clarity of the cornea are guaranteed by a delicate physiological, anatomic, and functional balance. For this reason, all the disorders, including those of genetic origin, that compromise this state of harmony can lead to opacity and eventually vision loss.

Oral Mucosa-Derived Induced Pluripotent Stem Cells from Patients with Ectrodactyly-Ectodermal Dysplasia-Clefting Syndrome.

Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) syndrome is a rare monogenic disease with autosomal dominant inheritance caused by mutations in the TP63 gene, leading to progressive corneal keratinocyte loss, limbal stem cell deficiency (LSCD), and eventually blindness. Currently, there is no treatment available to cure or slow down the keratinocyte loss. Human oral mucosal epithelial stem cells (hOMESCs), which are a mixed population of keratinocyte precursor stem cells, are used as source of autologous tissue for treatment of bilateral LSCD.

Optimized Protocol for Regeneration of the Conjunctival Epithelium Using the Cell Suspension Technique.

Purpose: To develop autologous tissue-engineered conjunctival epithelial sheets to be used as advanced therapy medicinal products for severe ocular surface disorders involving the conjunctiva.

Methods: Methods used aimed at 1) mapping the conjunctiva for identification of the stem cell location, 2) establishing proper cell culturing conditions, 3) identifying the proper scaffold, and 4) characterizing the conjunctival grafts better. For these purposes, immunostaining and PAS staining, serial cultivation of cells, and quantitative polymerase chain reaction ([INCREMENT]Np63α and MUC5AC) were performed.

Generation of a transgene-free human induced pluripotent stem cell line (UNIPDi001-A) from oral mucosa epithelial stem cells.

Human oral mucosa epithelial stem cells (hOMESCs) were obtained from a fresh oral biopsy collected from a healthy subject at the Fondazione Banca degli Occhi del Veneto (FBOV). An integration-free reprogramming protocol was applied exploiting episomal plasmids transfected into cells using a Nucleofector device. Around day 20 post transfection, several human induced pluripotent stem cell (hiPSC) colonies were manually picked and expanded.

Generation of a transgene-free induced pluripotent stem cells line (UNIPDi002-A) from oral mucosa epithelial stem cells carrying the R304Q mutation in TP63 gene.

Transgene free UNIPDi002-A-human induced pluripotent stem cell (hiPSC) line was generated by Sendai Virus Vectors reprogramming from human oral mucosal epithelial stem cells (hOMESCs) of a patient affected by ectrodactyly-ectodermal dysplasia-clefting (EEC)-syndrome, carrying a mutation in exon 8 of the TP63 gene (R304Q). The UNIPDi002-A-hiPSC line retained the mutation of the parental R304Q-hOMESCs and displayed a normal karyotype. No residual expression of transgenes nor Sendai virus vector sequences were detected in the line at passage 8.

Induced pluripotent stem cells line (UNIPDi003-A) from a patient affected by EEC syndrome carrying the R279H mutation in TP63 gene.

Oral mucosa epithelial stem cells from a patient affected by Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) syndrome carrying the R279H mutation in the TP63 gene were reprogrammed into human induced pluripotent stem cells (hiPSCs) with episomal vectors. The generated UNIPDi003-A-hPSC line retained the mutation of the parental cells and showed a normal karyotype upon long term culture. Analysis of residual transgenes expression showed that the episomal vectors were eliminated from the cell line.

Multimodal imaging quality control of epithelia regenerated with cultured human donor corneal limbal epithelial stem cells.

Current imaging techniques for the characterization of differentiated corneal limbal stem cells are destructive and cannot be used in eye bank for monitoring the regenerated epithelium in culture. We presented a minimally invasive, multimodal, marker-free imaging method for the investigation of epithelia regenerated with cultured human donor corneal limbal epithelial stem cells. Two-photon fluorescence and harmonic generation signals were collected from specimens in culture and used for evaluating the structure and morphology of epithelia cultured on two different bio-scaffolds; in addition, donor human corneal tissues were used as controls.

Recombinant human serum albumin for corneal preservation.

Purpose: To study the performance of a completely synthetic organ culture (OC) preservation system containing recombinant human serum albumin (rHSA) for preservation of human donor corneas.

Methods: Twenty-four paired donor corneas were randomly collected, and one cornea from each donor was preserved in synthetic (experimental) and serum-based media (control). The tissues were assessed at day 0; after 6 days of preservation at room temperature (RT) in Cornea Trans and Cornea Prep II ; after 28 days at 31°C in Cornea Syn [with rHSA] and Cornea Max [with foetal calf serum (FCS)] and; 4-day post deswelling in Cornea Trans and Cornea Jet .

Towards xeno-free cultures of human limbal stem cells for ocular surface reconstruction.

Isolated limbal epithelial stem cells (LESCs) were cultured with or without a 3T3 murine fibroblast feeder-layer (FL) in 4 different culture media on culture plates or on denuded human amniotic membrane (AM) support and fibrin gel support: (1) control medium supplemented with fetal bovine serum; (2) control medium supplemented with the synthetic serum "XerumFree™ XF205" (XF); (3) CnT-20 medium supplemented with "XerumFree™ XF205" (CnT-XF) and (4) CnT-20 medium supplemented with human AB serum (CnT-AB). The three xenogeneic media were compared to standard condition (control + FL) and parameters assessed included cell morphology, proliferative potential, number of passages, assessment of clonogenic and abortive colonies, life span, ∆Np63α expression and epithelial morphology on AM. During serial cultivation of LESCs, most of the tested xeno-free media supported similar numbers of cell passages, total colony number, cumulative cell doublings (CCD) rates and expression of ∆Np63α compared to control.

A c.3037G>A mutation in FBN1 gene causing Marfan syndrome with an atypically severe phenotype.

Marfan syndrome is a pleiotropic connective tissue disease inherited as an autosomal dominant trait, mostly caused by mutations in the FBN1 gene, which is located on chromosome 15q21.1 and encoding fibrillin 1. We report a case of Marfan syndrome presenting with severe ocular and systemic manifestations, such as cardiac congenital anomalies.

Cytology of the healthy canine and feline ocular surface: comparison between cytobrush and impression technique.

Background: Impression cytology (IC) is a noninvasive technique in which filters are used to sample superficial layers of ocular epithelium.

Objectives: The aim of this study was to compare cytology specimens obtained by IC and cytobrush from healthy canine and feline eyes.

Methods: Dogs and cats were prospectively sampled using polytetrafluorethylene filters on the right eye, and cytobrush on the left eye.

Identification of novel X-linked gain-of-function RPGR-ORF15 mutation in Italian family with retinitis pigmentosa and pathologic myopia.

The aim of this study was to describe a new pathogenic variant in the mutational hot spot exon ORF15 of retinitis pigmentosa GTPase regulator (RPGR) gene within an Italian family with X-linked retinitis pigmentosa (RP), detailing its distinctive genotype-phenotype correlation with pathologic myopia (PM). All members of this RP-PM family underwent a complete ophthalmic examination. The entire open reading frames of RPGR and retinitis pigmentosa 2 genes were analyzed by Sanger sequencing.

Visualization of DNA G-quadruplexes in herpes simplex virus 1-infected cells.

We have previously shown that clusters of guanine quadruplex (G4) structures can form in the human herpes simplex-1 (HSV-1) genome. Here we used immunofluorescence and immune-electron microscopy with a G4-specific monoclonal antibody to visualize G4 structures in HSV-1 infected cells. We found that G4 formation and localization within the cells was virus cycle dependent: viral G4s peaked at the time of viral DNA replication in the cell nucleus, moved to the nuclear membrane at the time of virus nuclear egress and were later found in HSV-1 immature virions released from the cell nucleus.

Novel variants of RPGR in X-linked retinitis pigmentosa families and genotype-phenotype correlation.

Purpose: To identify novel mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene and retinitis pigmentosa 2 (RP2) gene underlying X-linked retinitis pigmentosa (XLRP) and assess genotype-phenotype correlations.

Methods: The patient cohort, consisting of 13 individuals from 3 unrelated XLRP families, underwent comprehensive ophthalmologic examination. The open reading frames of RPGR and RP2 were analyzed with Sanger sequencing in each patient.

Safety outcomes and long-term effectiveness of ex vivo autologous cultured limbal epithelial transplantation for limbal stem cell deficiency.

Purpose: To evaluate the safety and effectiveness of ex vivo autologous cultured limbal stem cell transplantation (CLET).

Methods: We reviewed the clinical records of 59 consecutive patients treated with 65 CLETs. Efficacy was graded 1 year after surgery as successful, partially successful or failed.

Personalized Stem Cell Therapy to Correct Corneal Defects Due to a Unique Homozygous-Heterozygous Mosaicism of Ectrodactyly-Ectodermal Dysplasia-Clefting Syndrome.

Unlabelled: : Ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome is a rare autosomal dominant disease caused by mutations in the p63 gene. To date, approximately 40 different p63 mutations have been identified, all heterozygous. No definitive treatments are available to counteract and resolve the progressive corneal degeneration due to a premature aging of limbal epithelial stem cells.