Whole exome sequencing of 491 individuals with inherited retinal diseases reveals a large spectrum of variants and identification of novel candidate genes.

BACKGROUND: Inherited retinal diseases (IRDs) include a range of vision loss conditions caused by variants in different genes. The clinical and genetic heterogeneity make identification of the genetic cause challenging. Here, a cohort of 491 unsolved cases from our cohort of Israeli and Palestinian families with IRDs underwent whole exome sequencing (WES), including detection of CNVs as well as single nucleotide variants (SNVs). METHODS: All participants underwent clinical examinations. Following WES on DNA samples by 3 billion, initial SNV analysis was performed by 3 billion and SNV and CNV analysis by Franklin Genoox. The CNVs indicated by the programme were confirmed by PCR followed by gel electrophoresis. RESULTS: WES of 491 IRD cases revealed the genetic cause of disease in 51% of cases, of which 11% were due wholly or in part to CNVs. In two cases, we clarified previously incorrect or unclear clinical diagnoses. This analysis also identified ESRRB and DNM1 as potential novel genes. CONCLUSION: This analysis is the most extensive one to include CNVs to examine IRD causing genes in the Israeli and Palestinian populations. It has allowed us to identify the causative variant of many patients with IRDs including ones with unclear diagnoses and potential novel genes.

Bilateral Intratonsillar Abscesses: A Deceiving Symmetrical Oral Bulging.

BACKGROUND: Unilateral intratonsillar abscess (ITA) is an underreported, well-known complication of acute tonsillitis. The prevalence of unilateral ITA compared to peritonsillar abscess (PTA) is 1:14. However, bilateral ITA is an extremely rare entity, with only four cases reported thus far. OBJECTIVES: To describe past cases and our experience, elaborating the diagnostic challenge and the surgical treatment for bilateral ITA. METHODS: We conducted a literature search in the PubMed database using the key words intra-tonsillar abscess, tonsillar abscess, bilateral tonsillar abscess, bilateral intra-tonsillar abscess and bilateral peritonsillar abscess. Our search was limited to the years 1980 to 2020. RESULTS: We found that only four cases of bilateral ITA were previously published. All were characterized by a delay in diagnosis with a median of 10 days (4-14 days), symmetrical oral cavity appearance, enlarged bilateral kissing tonsils, and subsequent treatment by surgical drainage/paracentesis. Respiratory compromise was a concern in most cases. Our patient was treated with bilateral quinsy tonsillectomy and had a prompt recovery. CONCLUSIONS: Bilateral ITA is a rare, deceiving entity, with a diagnosis delay attributed to the symmetrical oral bulging. We present the fifth case reported and the first ever reported in a pediatric patient. We describe the assumed pathogenesis and the main characteristics among all five patients, emphasizing the important role of a high index of suspicion and appropriate imaging, guiding to proper diagnosis and treatment.

Sleep-related breathing disorders in young orthodontic patients.

INTRODUCTION: This study aimed to find out the frequency of sleep-related breathing disorders (SRBD) in young orthodontic patients in Israel. SRBD is characterized by prolonged upper airway obstruction during sleep. METHODS: The study group consisted of 309 children aged 6-17 years who attended the Orthodontic Clinic at Hadassah Medical Center. Parents were asked to complete a translated validated Pediatric Sleep Questionnaire. RESULTS: Of the examined children, 10% were at high risk for SRBD. Boys were at higher risk for SRBD and were at high risk at a younger age than girls. Girls had a low risk of SRBD after adenotonsillectomy, whereas 50% of the boys that underwent adenotonsillectomy were at high risk for SRBD. CONCLUSIONS: Our findings propose that 10% of the children aged 6-17 years, who were seeking orthodontic consultation at our medical center, were at high risk for SRBD. Boys were significantly at a higher risk for SRBD than girls and were at high risk at a younger age. It is important to screen young orthodontic patients for SRBD and to refer high-risk patients to their physicians for further evaluation and treatment.

Identification of autosomal recessive novel genes and retinal phenotypes in members of the solute carrier (SLC) superfamily.

PURPOSE: This study aimed to investigate the clinical and genetic aspects of solute carrier (SLC) genes in inherited retinal diseases (IRDs). METHODS: Exome sequencing data were filtered to identify pathogenic variants in SLC genes. Analysis of transcript and protein expression was performed on fibroblast cell lines and retinal sections. RESULTS: Comprehensive analysis of 433 SLC genes in 913 exome sequencing IRD samples revealed homozygous pathogenic variants in 6 SLC genes, including 2 candidate novel genes, which were 2 variants in SLC66A1, causing autosomal recessive retinitis pigmentosa (ARRP), and a variant in SLC39A12, causing autosomal recessive mild widespread retinal degeneration with marked macular involvement. In addition, we present 4 families with ARRP and homozygous null variants in SLC37A3 that were previously suggested to cause retinitis pigmentosa, 2 of which cause exon skipping. The recently reported SLC4A7- c.2007dup variant was found in 2 patients with ARRP resulting in the absence of protein. Finally, variants in SLC24A1 were found in 4 individuals with either ARRP or congenital stationary night blindness. CONCLUSION: We report on SLC66A1 and SLC39A12 as candidate novel IRD genes, establish SLC37A3 pathogenicity, and provide further evidence of SLC4A7 as IRD genes. We extend the phenotypic spectrum of SLC24A1 and suggest that its ARRP phenotype may be more common than previously reported.

Sustained release varnish containing chlorhexidine for prevention of Streptococcus mutans biofilm formation on voice prosthesis surface: an in vitro study.

OBJECTIVES: In this study, we aimed to develop a novel, sustained release varnish (SRV) for voice prostheses (VP) releasing chlorhexidine (CHX), for the prevention of biofilm formation caused by the common oral bacteria Streptococcus mutans on VP surfaces. METHODS: This study was performed in an in vitro model as a step towards future in vivo trials. VPs were coated with a SRV containing CHX (SRV-CHX) or SRV alone (placebo-SRV) that were daily exposed to S. mutans. The polymeric materials of SRV were composed of ethylcellulose and PEG-400. Biofilm formation was assessed by DNA quantification (qPCR), crystal violet staining, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and kinetics experiments. RESULTS: The amount of DNA in the biofilms formed by S. mutans on VP surfaces coated once with SRV-CHX (1.024 ± 0.218 ng DNA/piece) was 58.5 ± 8.8% lower than that of placebo-SRV-coated VPs (2.465 ± 0.198 ng DNA/piece) after a 48-h exposure to S. mutans (p = 0.038). Reduced biofilm mass on SRV-CHX-coated VPs was visually confirmed by CLSM and SEM. CV staining of SRV-CHX single-coated VPs that have been exposed to S. mutans nine times showed a 98.1 ± 0.2% reduction in biofilm mass compared to placebo-SRV-coated VPs (p = 0.003). Kinetic experiments revealed that SRV-CHX triple-coated VPs could delay bacterial growth for 23 days. CONCLUSIONS: Coating VPs with SRV-CHX has an inhibitory effect on biofilm formation and prevents bacterial growth in their vicinities. This study is a proof-of-principle that paves the way for developing new clinical means for reducing both VPs' bacterial biofilm formation and device failure.

Human Nasal Turbinate Tissues in Organ Culture as a Model for Human Cytomegalovirus Infection at the Mucosal Entry Site.

The initial events of viral infection at the primary mucosal entry site following horizontal person-to-person transmission have remained ill defined. Our limited understanding is further underscored by the absence of animal models in the case of human-restricted viruses, such as human cytomegalovirus (HCMV), a leading cause of congenital infection and a major pathogen in immunocompromised individuals. Here, we established a novel ex vivo model of HCMV infection in native human nasal turbinate tissues. Nasal turbinate tissue viability and physiological functionality were preserved for at least 7 days in culture. We found that nasal mucosal tissues were susceptible to HCMV infection, with predominant infection of ciliated respiratory epithelial cells. A limited viral spread was demonstrated, involving mainly stromal and vascular endothelial cells within the tissue. Importantly, functional antiviral and proleukocyte chemotactic signaling pathways were significantly upregulated in the nasal mucosa in response to infection. Conversely, HCMV downregulated the expression of nasal epithelial cell-related genes. We further revealed tissue-specific innate immune response patterns to HCMV, comparing infected human nasal mucosal and placental tissues, representing the viral entry and the maternal-to-fetal transmission sites, respectively. Taken together, our studies provide insights into the earliest stages of HCMV infection. Studies in this model could help evaluate new interventions against the horizontal transmission of HCMV.IMPORTANCE HCMV is a ubiquitous human pathogen causing neurodevelopmental disabilities in congenitally infected children and severe disease in immunocompromised patients. The earliest stages of HCMV infection in the human host have remained elusive in the absence of a model for the viral entry site. Here, we describe the establishment and use of a novel nasal turbinate organ culture to study the initial steps of viral infection and the consequent innate immune responses within the natural complexity and the full cellular repertoire of human nasal mucosal tissues. This model can be applied to examine new antiviral interventions against the horizontal transmission of HCMV and potentially that of other viruses.

Voice Prosthesis Coated with Sustained Release Varnish Containing Clotrimazole Shows Long-Term Protection against Candida albicans: An In Vitro Study.

Fungal biofilm formation on voice prosthesis (VP) is a major health problem that requires repeated replacement of the prosthesis. Candida albicans is one of the pathogens that frequently inhabits the VP. We proposed that coating VPs with sustained-release varnish (SRV) containing clotrimazole (CTZ) might prevent fungal biofilm formation. The long-term antifungal activities of SRV-CTZ- versus SRV-placebo-coated VPs was tested daily by measuring the inhibition zone of C. albicans seeded on agar plates or by measuring the fungal viability of C. albicans in suspension. The extent of biofilm formation on coated VPs was analyzed by confocal microscopy and scanning electron microscopy. We observed that SRV-CTZ-coated VPs formed a significant bacterial inhibition zone around the VPs and prevented the growth of C. albicans in suspension during the entire testing period of 60 days. Fungal biofilms were formed on placebo-coated VPs, while no significant biofilms were observed on SRV-CTZ-coated VPs. HPLC analysis shows that CTZ is continuously released during the whole test period of 60 days at a concentration above the minimal fungistatic concentration. In conclusion, coating VPs with an SRV-CTZ film is a potential effective method for prevention of fungal infections and biofilm formation on VPs.

Bi-allelic Truncating Mutations in CEP78, Encoding Centrosomal Protein 78, Cause Cone-Rod Degeneration with Sensorineural Hearing Loss.

Inherited retinal diseases (IRDs) are a diverse group of genetically and clinically heterogeneous retinal abnormalities. The present study was designed to identify genetic defects in individuals with an uncommon combination of autosomal recessive progressive cone-rod degeneration accompanied by sensorineural hearing loss (arCRD-SNHL). Homozygosity mapping followed by whole-exome sequencing (WES) and founder mutation screening revealed two truncating rare variants (c.893-1G>A and c.534delT) in CEP78, which encodes centrosomal protein 78, in six individuals of Jewish ancestry with CRD and SNHL. RT-PCR analysis of CEP78 in blood leukocytes of affected individuals revealed that the c.893-1G>A mutation causes exon 7 skipping leading to deletion of 65bp, predicted to result in a frameshift and therefore a truncated protein (p.Asp298Valfs(∗)17). RT-PCR analysis of 17 human tissues demonstrated ubiquitous expression of different CEP78 transcripts. RNA-seq analysis revealed three transcripts in the human retina and relatively higher expression in S-cone-like photoreceptors of Nrl-knockout retina compared to rods. Immunohistochemistry studies in the human retina showed intense labeling of cone inner segments compared to rods. CEP78 was reported previously to interact with c-nap1, encoded by CEP250 that we reported earlier to cause atypical Usher syndrome. We conclude that truncating mutations in CEP78 result in a phenotype involving both the visual and auditory systems but different from typical Usher syndrome.

The association between video-nystagmography and sensory organization test of computerized dynamic posturography in patients with vestibular symptoms.

OBJECTIVE: Vertigo is a complex symptom which imposes diagnostic and treatment challenges. Laboratory evaluation of vertigo includes video-nystagmography (VNG) and computerized dynamic posturography (CDP) for the evaluation of different aspects of this complaint. There are vague indications for each test and potential disagreements between them. The aim of this study is to examine the association between the test results of the VNG and sensory organization test (SOT) of CDP in patients referred for both vestibular tests. METHODS: Retrospective data regarding 56 patients age 17-82 years were collected. Patients suffered vestibular complaints and were referred for VNG and CDP evaluation on the same day. The level of agreement between VNG (including caloric test) and the vestibular input of the SOT for each patient was calculated. RESULTS: Among the study group, 10 showed abnormal caloric test results, of which 3 (5.4%) had normal vestibular input in the SOT, and 7 (12.5%) had impaired input (p = 0.724). Spontaneous nystagmus was recorded in 13 patients by VNG, of which 2(3.6%) had normal vestibular input and 11(19.6%) had impaired vestibular input (p = 0.056). CONCLUSIONS: This study shows no statistically significant association between the VNG test and SOT test results. Our results emphasize the difference between the tested aspects in each laboratory test, and the need to define specific indications for each of them. There is a marginally significant association between impaired vestibular input and spontaneous nystagmus, demonstrating the non-localizing nature of this sign.

A homozygous founder missense variant in arylsulfatase G abolishes its enzymatic activity causing atypical Usher syndrome in humans.

PURPOSE: We aimed to identify the cause of disease in patients suffering from a distinctive, atypical form of Usher syndrome. METHODS: Whole-exome and genome sequencing were performed in five patients from three families of Yemenite Jewish origin, suffering from distinctive retinal degeneration phenotype and sensorineural hearing loss. Functional analysis of the wild-type and mutant proteins was performed in human fibrosarcoma cells. RESULTS: We identified a homozygous founder missense variant, c.133G>T (p.D45Y) in arylsulfatase G (ARSG). All patients shared a distinctive retinal phenotype with ring-shaped atrophy along the arcades engirdling the fovea, resulting in ring scotoma. In addition, patients developed moderate to severe sensorineural hearing loss. Both vision and hearing loss appeared around the age of 40 years. The identified variant affected a fully conserved amino acid that is part of the catalytic site of the enzyme. Functional analysis of the wild-type and mutant proteins showed no basal activity of p.D45Y. CONCLUSION: Homozygosity for ARSG-p.D45Y in humans leads to protein dysfunction, causing an atypical combination of late-onset Usher syndrome. Although there is no evidence for generalized clinical manifestations of lysosomal storage diseases in this set of patients, we cannot rule out the possibility that mild and late-onset symptoms may appear.

Hearing loss in vitiligo: current concepts and review.

The objective of this study was to describe the occurrence, clinical manifestations, audiometric findings, pathogenesis and approach to sensorineural hearing loss (SNHL) among patients diagnosed with vitiligo with a review of the literature. We present a systematic review of the literature on cases of SNHL in patients diagnosed with vitiligo and studies conducted to investigate audiometric changes in such patients. Data on presentation, diagnosis and medical approach were reviewed. A total of 21 studies and case reports revealed at least 102 cases of SNHL in patients diagnosed with vitiligo. Arguments for a common causative etiology related to melanocyte function were mentioned in most of the literature. Evaluation of hearing function among all patients diagnosed with vitiligo seems to be an accepted approach; it should include audiometry, otoacoustic emissions (OAE) and ABR measurements. Extra precaution to prevent ototoxic or noise-induced hearing loss is strongly recommended. Further research is needed to better understand its pathogenesis.

Mutations in ARL2BP, encoding ADP-ribosylation-factor-like 2 binding protein, cause autosomal-recessive retinitis pigmentosa.

Retinitis pigmentosa (RP) is a genetically heterogeneous retinal degeneration characterized by photoreceptor death, which results in visual failure. Here, we used a combination of homozygosity mapping and exome sequencing to identify mutations in ARL2BP, which encodes an effector protein of the small GTPases ARL2 and ARL3, as causative for autosomal-recessive RP (RP66). In a family affected by RP and situs inversus, a homozygous, splice-acceptor mutation, c.101-1G>C, which alters pre-mRNA splicing of ARLBP2 in blood RNA, was identified. In another family, a homozygous c.134T>G (p.Met45Arg) mutation was identified. In the mouse retina, ARL2BP localized to the basal body and cilium-associated centriole of photoreceptors and the periciliary extension of the inner segment. Depletion of ARL2BP caused cilia shortening. Moreover, depletion of ARL2, but not ARL3, caused displacement of ARL2BP from the basal body, suggesting that ARL2 is vital for recruiting or anchoring ARL2BP at the base of the cilium. This hypothesis is supported by the finding that the p.Met45Arg amino acid substitution reduced binding to ARL2 and caused the loss of ARL2BP localization at the basal body in ciliated nasal epithelial cells. These data demonstrate a role for ARL2BP and ARL2 in primary cilia function and that this role is essential for normal photoreceptor maintenance and function.

A homozygous nonsense CEP250 mutation combined with a heterozygous nonsense C2orf71 mutation is associated with atypical Usher syndrome.

BACKGROUND: Usher syndrome (USH) is a heterogeneous group of inherited retinitis pigmentosa (RP) and sensorineural hearing loss (SNHL) caused by mutations in at least 12 genes. Our aim is to identify additional USH-related genes. METHODS: Clinical examination included visual acuity test, funduscopy and electroretinography. Genetic analysis included homozygosity mapping and whole exome sequencing (WES). RESULTS: A combination of homozygosity mapping and WES in a large consanguineous family of Iranian Jewish origin revealed nonsense mutations in two ciliary genes: c.3289C>T (p.Q1097*) in C2orf71 and c.3463C>T (p.R1155*) in centrosome-associated protein CEP250 (C-Nap1). The latter has not been associated with any inherited disease and the c.3463C>T mutation was absent in control chromosomes. Patients who were double homozygotes had SNHL accompanied by early-onset and severe RP, while patients who were homozygous for the CEP250 mutation and carried a single mutant C2orf71 allele had SNHL with mild retinal degeneration. No ciliary structural abnormalities in the respiratory system were evident by electron microscopy analysis. CEP250 expression analysis of the mutant allele revealed the generation of a truncated protein lacking the NEK2-phosphorylation region. CONCLUSIONS: A homozygous nonsense CEP250 mutation, in combination with a heterozygous C2orf71 nonsense mutation, causes an atypical form of USH, characterised by early-onset SNHL and a relatively mild RP. The severe retinal involvement in the double homozygotes indicates an additive effect caused by nonsense mutations in genes encoding ciliary proteins.

T cell help induces Myc transcriptional bursts in germinal center B cells during positive selection.

Antibody affinity maturation occurs in secondary lymphoid organs within germinal centers (GCs). At these sites, B cells mutate their antibody-encoding genes in the dark zone, followed by preferential selection of the high-affinity variants in the light zone by T cells. The strength of the T cell-derived selection signals is proportional to the B cell receptor affinity and to the magnitude of subsequent Myc expression. However, because the lifetime of Myc mRNA and its corresponding protein is very short, it remains unclear how T cells induce sustained Myc levels in positively selected B cells. Here, by direct visualization of mRNA and active transcription sites in situ, we found that an increase in transcriptional bursts promotes Myc expression during B cell positive selection in GCs. Elevated T cell help signals predominantly enhance the percentage of cells expressing Myc in GCs as opposed to augmenting the quantity of Myc transcripts per individual cell. Visualization of transcription start sites in situ revealed that T cell help promotes an increase in the frequency of transcriptional bursts at the Myc locus in GC B cells located primarily in the LZ apical rim. Thus, the rise in Myc, which governs positive selection of B cells in GCs, reflects an integration of transcriptional activity over time rather than an accumulation of transcripts at a specific time point.

VPS 45-associated primary infantile myelofibrosis--successful treatment with hematopoietic stem cell transplantation.

PMF of infancy is a recently described autosomal recessive disorder presenting with severe bone marrow failure, accelerated neutrophil apoptosis, and significant platelet dysfunction, caused by a mutation in the VPS45 gene. In this study, we update our group of patients with PMF, highlighting different aspects of this disease, and evaluating the effectiveness of HSCT for the treatment of this disorder. Update of clinical data, hematological features, molecular studies, treatment and final outcome of four children diagnosed with VPS 45-associated PMF of infancy. The patients described had clinical and hematological findings consistent with MF. Molecular studies showed that all patients were homozygous for the Thr224Asn mutation in the VPS 45 gene. HSCT was carried out in three patients and was successful in two. VPS 45-associated MF is a novel primary immune deficiency that can be successfully corrected by HSCT if applied early in the course of disease using appropriate conditioning. The diagnosis of VPS 45-associated PMF should be considered in all children presenting with SCN with subsequent development of pancytopenia. Long-term follow-up of these patients is necessary to identify extra-hematological manifestations of VPS45 deficiency.

The impact of vestibular symptoms and electronystagmography results on recovery from sudden sensorineural hearing loss.

OBJECTIVES: Idiopathic sudden sensorineural hearing loss (SSNHL) represents a frequently encountered otological entity, of various types and severity, with an array of associated symptoms including vertigo. This is a devastating life-changing condition with a blurry prognosis. The objective of this study was to determine the clinical association of vestibular impairment by electronystagmography (ENG) and caloric tests, and their ability to predict prognosis. METHODS: An observational, crossectional study was carried out amongst patients admitted with SSNHL. Each consenting patient had an audiometry test performed on admission as well as ENG and caloric tests. Treatment included oral steroids and carbogen with intratympanic steroids used only as salvage treatment. Follow-up was completed after 6 months when hearing gains were evaluated. Finally, an association was sought between the rate of recovery and ENG and caloric test results. RESULTS: Of 35 patients included, marked recovery was seen in patients without vertigo when compared to those with vertigo (p=0.003). A statistically significant association was found between the presence of vertigo and hearing deterioration (p=0.008). More so, normal electronystagmography results were associated with marked recovery (p=0.04). CONCLUSIONS: The vestibular end organs are both subjectively and objectively affected in SSNHL as demonstrated by the abnormal ENG and caloric tests in our study despite the small sample size. Concomitant vestibular involvement carries poorer prognosis and routine identification may help foresee the recovery of patients with SSNHL and as such, aid in patient counseling. ENG and caloric tests are easily available and may be recommended for all patients with SSNHL.

Sinonasal Stent Coated with Sustained-Release Varnish of Mometasone Furoate Inhibits Pro-Inflammatory Cytokine Release from Macrophages: An In Vitro Study.

The aim of the study was to develop a sustained-release varnish (SRV) containing mometasone furoate (MMF) for sinonasal stents (SNS) to reduce mucosa inflammation in the sinonasal cavity. The SNS' segments coated with SRV-MMF or an SRV-placebo were incubated daily in a fresh DMEM at 37 °C for 20 days. The immunosuppressive activity of the collected DMEM supernatants was tested on the ability of mouse RAW 264.7 macrophages to secrete the cytokines' tumor necrosis factor α (TNFα) and interleukin (IL)-10 and IL-6 in response to lipopolysaccharide (LPS). The cytokine levels were determined by respective Enzyme-Linked Immunosorbent Assays (ELISAs). We found that the daily amount of MMF released from the coated SNS was sufficient to significantly inhibit LPS-induced IL-6 and IL-10 secretion from the macrophages up to days 14 and 17, respectively. SRV-MMF had, however, only a mild inhibitory effect on LPS-induced TNFα secretion as compared to the SRV-placebo-coated SNS. In conclusion, the coating of SNS with SRV-MMF provides a sustained delivery of MMF for at least 2 weeks, maintaining a level sufficient for inhibiting pro-inflammatory cytokine release. This technological platform is, therefore, expected to provide anti-inflammatory benefits during the postoperative healing period and may play a significant role in the future treatment of chronic rhinosinusitis.

Homozygous Knockout of Cep250 Leads to a Relatively Late-Onset Retinal Degeneration and Sensorineural Hearing Loss in Mice.

Purpose: Usher syndrome (USH) is the most common syndromic inherited retinal disease, causing retinitis pigmentosa and sensorineural hearing loss. We reported previously that a nonsense mutation in the centrosome-associated protein CEP250 gene (encoding C-Nap1) causes atypical USH in patients of Iranian Jewish origin. To better characterize CEP250, we aimed to generate and study a knockout (KO) mouse model for Cep250. Methods: Mice heterozygous for a "knockout-first" Cep250 construct were generated and bred with Cre recombinase mice to generate the null allele and produce homozygous Cep250 KO mice. Retinal function was evaluated by full-field electroretinography (ffERG) at variable ages, and retinal structure changes were examined using histological analysis. Hearing thresholds were detected using auditory brainstem response (ABR) at the age of 20 months. Results: The Cep250 KO mouse model was generated by activating a construct harboring a deletion of exons 6 and 7. At 6 months, the ffERG was normal, but it decreased gradually with age. For both photopic and scotopic ffERG responses, very low amplitudes were evident at 20 months. Histological analysis confirmed late-onset retinal degeneration. ABR tests illustrated that hearing threshold significantly increased at the age of 20 months. Conclusions: Although most USH animal models have normal retinal function and structure, the Cep250 KO mouse model shows both retinal degeneration and hearing loss with a relatively late age of onset. This model may shed more light on CEP250-associated retinal and hearing deficits and represents an efficient platform for the development of treatment modalities for USH. Translational Relevance: Our study demonstrates better understanding of Cep250-associated retinal and hearing disease in a mouse model and may help in developing more efficient gene therapy modalities.

Refractory Pseudomonas aeruginosa infections treated with phage PASA16: A compassionate use case series.

BACKGROUND: A growing number of compassionate phage therapy cases were reported in the last decade, with a limited number of clinical trials conducted and few unsuccessful clinical trials reported. There is only a little evidence on the role of phages in refractory infections. Our objective here was to present the largest compassionate-use single-organism/phage case series in 16 patients with non-resolving Pseudomonas aeruginosa infections. METHODS: We summarized clinical phage microbiology susceptibility data, administration protocol, clinical data, and outcomes of all cases treated with PASA16 phage. In all intravenous phage administrations, PASA16 phage was manufactured and provided pro bono by Adaptive Phage Therapeutics. PASA16 was administered intravenously, locally to infection site, or by topical use to 16 patients, with data available for 15 patients, mainly with osteoarticular and foreign-device-associated infections. FINDINGS: A few minor side effects were noted, including elevated liver function enzymes and a transient reduction in white blood cell count. Good clinical outcome was documented in 13 out of 15 patients (86.6%). Two clinical failures were reported. The minimum therapy duration was 8 days with a once- to twice-daily regimen. CONCLUSIONS: PASA16 with antibiotics was found to be relatively successful in patients for whom traditional treatment approaches have failed previously. Such pre-phase-1 cohorts can outline potential clinical protocols and facilitate the design of future trials. FUNDING: The study was funded in part by The Israeli Science Foundation IPMP (ISF_1349/20), Rosetrees Trust (A2232), United States-Israel Binational Science Foundation (2017123), and the Milgrom Family Support Program.