Shared and organ-specific gene-expression programs during the development of the cochlea and the superior olivary complex.

The peripheral and central auditory subsystems together form a complex sensory network that allows an organism to hear. The genetic programs of the two subsystems must therefore be tightly coordinated during development. Yet, their interactions and common expression pathways have never been systematically explored. MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression and are essential for normal development of the auditory system. We performed mRNA and small-RNA sequencing of organs from both auditory subsystems at three critical developmental timepoints (E16, P0, P16) to obtain a comprehensive and unbiased insight of their expression profiles. Our analysis reveals common and organ-specific expression patterns for differentially regulated mRNAs and miRNAs, which could be clustered with a particular selection of functions such as inner ear development, Wnt signalling, K+ transport, and axon guidance, based on gene ontology. Bioinformatics detected enrichment of predicted targets of specific miRNAs in the clusters and predicted regulatory interactions by monitoring opposite trends of expression of miRNAs and their targets. This approach identified six miRNAs as strong regulatory candidates for both subsystems. Among them was miR-96, an established critical factor for proper development in both subsystems, demonstrating the strength of our approach. We suggest that other miRNAs identified by this analysis are also common effectors of proper hearing acquirement. This first combined comprehensive analysis of the developmental program of the peripheral and central auditory systems provides important data and bioinformatics insights into the shared genetic program of the two sensory subsystems and their regulation by miRNAs.

Maternal and Cord Anti-SARS-CoV-2-Spike IgG following COVID-19 Vaccination versus Infection during Pregnancy: A Prospective Study, Israel October 2021-March 2022.

OBJECTIVE: Defining how pregnant women respond to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vaccination is critical to optimize vaccination strategies that protect mother and infant at the epidemic. This study aimed to compare anti-SARS-CoV-2-spike immunoglobulin G (IgG) of vaccinated versus infected women and to determine the optimal timing of maternal vaccination during pregnancy at the time of epidemic. STUDY DESIGN: We collected maternal/cord blood at delivery (October 2021-March 2022) and measured anti-SARS-CoV-2-spike IgG geometric mean concentrations (IgG-GMCs) using a quantitative immunoassay. We compared groups according to timing and number of doses and correlated maternal and fetal IgG levels. We described the proportion of women with IgG levels above the 150 AU/mL positivity threshold according to the timing of infection/vaccination and performed a subanalysis for maternal IgG-GMC levels pre- and during the Omicron wave. RESULTS: We included 238 vaccinated women, 125 who received two doses and 113 three doses, and 48 unvaccinated infected women. All groups infected/vaccinated in the second or third trimester had an IgG-GMC above the positivity threshold. Third-trimester vaccination (second/third dose) resulted in higher maternal and cord-blood IgG-GMC compared to the second trimester (maternal-IgG: 102,32 vs. 4,325 AU/mL, p < 0.001; cord-IgG: 12,113 vs. 8,112 AU/mL, p < 0.001). Compared with infected-only women, a higher proportion of vaccinated women with ≥2 doses and their newborns had IgG levels above the positivity threshold at all time points. In vaccinated women, there were higher maternal IgG-GMC levels during the Omicron wave than pre-Omicron. CONCLUSION: At the time of epidemic, receiving an additional COVID-19 vaccine dose in the third trimester resulted in a higher IgG-GMC compared to the second trimester. Relatively higher levels of maternal and cord IgG-GMC were achieved following vaccination than infection. Women infected during or before the first trimester might benefit from an additional third-trimester dose to prevent peripartum infection and to passively immunize their newborn. The higher levels of maternal IgG-GMC in the Omicron period are suggestive of hybrid immunity. KEY POINTS: · Higher maternal anti-SARS-IgGs in vaccinated → infected.. · Higher cord anti-SARS-IgGs in vaccinated → infected.. · Third-trimester vaccine resulted in high-cord IgG levels..

Identification and characterization of key long non-coding RNAs in the mouse cochlea.

The auditory system is a complex sensory network with an orchestrated multilayer regulatory programme governing its development and maintenance. Accumulating evidence has implicated long non-coding RNAs (lncRNAs) as important regulators in numerous systems, as well as in pathological pathways. However, their function in the auditory system has yet to be explored. Using a set of specific criteria, we selected four lncRNAs expressed in the mouse cochlea, which are conserved in the human transcriptome and are relevant for inner ear function. Bioinformatic characterization demonstrated a lack of coding potential and an absence of evolutionary conservation that represent properties commonly shared by their class members. RNAscope®  analysis of the spatial and temporal expression profiles revealed specific localization to inner ear cells. Sub-cellular localization analysis presented a distinct pattern for each lncRNA and mouse tissue expression evaluation displayed a large variability in terms of level and location. Our findings establish the expression of specific lncRNAs in different cell types of the auditory system and present a potential pathway by which the lncRNA Gas5 acts in the inner ear. Studying lncRNAs and deciphering their functions may deepen our knowledge of inner ear physiology and morphology and may reveal the basis of as yet unresolved genetic hearing loss-related pathologies. Moreover, our experimental design may be employed as a reference for studying other inner ear-related lncRNAs, as well as lncRNAs expressed in other sensory systems.

Expression pattern of cochlear microRNAs in the mammalian auditory hindbrain.

The auditory system comprises the auditory periphery, engaged in sound transduction and the central auditory system, implicated in auditory information processing and perception. Recently, evidence mounted that the mammalian peripheral and central auditory systems share a number of genes critical for proper development and function. This bears implication for auditory rehabilitation and evolution of the auditory system. To analyze to which extent microRNAs (miRNAs) belong to genes shared between both systems, we characterize the expression pattern of 12 cochlea-abundant miRNAs in the central auditory system. Quantitative real-time PCR (qRT-PCR) demonstrated expression of all 12 genes in the cochlea, the auditory hindbrain and the non-auditory prefrontal cortex (PFC) at embryonic stage (E)16 and postnatal stages (P)0 and P30. Eleven of them showed differences in expression between tissues and nine between the developmental time points. Hierarchical cluster analysis revealed that the temporal expression pattern in the auditory hindbrain was more similar to the PFC than to the cochlea. Spatiotemporal expression analysis by RNA in situ hybridization demonstrated widespread expression throughout the cochlear nucleus complex (CNC) and the superior olivary complex (SOC) during postnatal development. Altogether, our data indicate that miRNAs represent a relevant class of genetic factors functioning across the auditory system. Given the importance of gene regulatory network (GRN) components for development, physiology and evolution, the 12 miRNAs provide promising entry points to gain insights into their molecular underpinnings in the auditory system.

Spectrum of genes for inherited hearing loss in the Israeli Jewish population, including the novel human deafness gene ATOH1.

Mutations in more than 150 genes are responsible for inherited hearing loss, with thousands of different, severe causal alleles that vary among populations. The Israeli Jewish population includes communities of diverse geographic origins, revealing a wide range of deafness-associated variants and enabling clinical characterization of the associated phenotypes. Our goal was to identify the genetic causes of inherited hearing loss in this population, and to determine relationships among genotype, phenotype, and ethnicity. Genomic DNA samples from informative relatives of 88 multiplex families, all of self-identified Jewish ancestry, with either non-syndromic or syndromic hearing loss, were sequenced for known and candidate deafness genes using the HEar-Seq gene panel. The genetic causes of hearing loss were identified for 60% of the families. One gene was encountered for the first time in human hearing loss: ATOH1 (Atonal), a basic helix-loop-helix transcription factor responsible for autosomal dominant progressive hearing loss in a five-generation family. Our results show that genomic sequencing with a gene panel dedicated to hearing loss is effective for genetic diagnoses in a diverse population. Comprehensive sequencing enables well-informed genetic counseling and clinical management by medical geneticists, otolaryngologists, audiologists, and speech therapists and can be integrated into newborn screening for deafness.

Cryopreservation of Stromal Vascular Fraction Cells Reduces Their Counts but Not Their Stem Cell Potency.

Adipose-derived stem cells are derived from the nonfat component of adipose tissue termed the stromal vascular fraction (SVF). The use of freshly isolated autologous SVF cells as an alternative to adult stem cells is becoming more common. Repeated SVF administration for improved clinical outcomes is complicated by the need for repeated liposuction. This can be overcome by cryopreservation of SVF cells. The current study aimed to assess whether SVF cells retain their stem cell potency during cryopreservation. METHODS: SVF cells isolated from lipoaspirates (donor age: 46.1 ± 11.7 y; body mass index: 29.3 ± 4.8 kg/m2) were analyzed either immediately after isolation or following cryopreservation at -196°C. Analyses included assessment of nucleated cell counts by methylene blue staining, colony-forming unit fibroblast counts, surface marker expression using a flow cytometric panel (CD45, CD34, CD31, CD73, CD29, and CD105), expansion in culture, and differentiation to fat and bone. RESULTS: While cryopreservation reduced the number of viable SVF cells, stem cell potency was preserved, as demonstrated by no significant difference in the proliferation, surface marker expression in culture, bone and fat differentiation capacity, and the number of colony-forming unit fibroblasts in culture, in cryopreserved versus fresh SVF cells. Importantly, reduced cell counts of cryopreserved cells were due, mainly, to a reduction in hematopoietic CD45+ cells, which was accompanied by increased proportions of CD45-CD34+CD31- stem cell progenitor cells compared to fresh SVF cells. CONCLUSIONS: Cryopreservation of SVF cells did not affect their in vitro stem cell potency and may therefore enable repeated SVF cell administrations, without the need for repeated liposuction.