Use of Recombinant Adenovirus Vectored Consensus IFN-α to Avert Severe Arenavirus Infection

Several arenaviruses can cause viral hemorrhagic fever, a severe disease with case-fatality rates in hospitalized individuals ranging from 15-30%. Because of limited prophylaxis and treatment options, new medical countermeasures are needed for these viruses classified by the National Institutes of Allergy and Infectious Diseases (NIAID) as top priority biodefense Category A pathogens. Recombinant consensus interferon alpha (cIFN-α) is a licensed protein with broad clinical appeal. However, while cIFN-α has great therapeutic value, its utility for biodefense applications is hindered by its short in vivo half-life, mode and frequency of administration, and costly production. To address these limitations, we describe the use of DEF201, a replication-deficient adenovirus vector that drives the expression of cIFN-α, for pre- and post-exposure prophylaxis of acute arenaviral infection modeled in hamsters. Intranasal administration of DEF201 24 h prior to challenge with Pichindé virus (PICV) was highly effective at protecting animals from mortality and preventing viral replication and liver-associated disease. A significant protective effect was still observed with a single dosing of DEF201 given two weeks prior to PICV challenge. DEF201 was also efficacious when administered as a treatment 24 to 48 h post-virus exposure. The protective effect of DEF201 was largely attributed to the expression of cIFN-α, as dosing with a control empty vector adenovirus did not protect hamsters from lethal PICV challenge. Effective countermeasures that are highly stable, easily administered, and elicit long lasting protective immunity are much needed for arena and other viral infections. The DEF201 technology has the potential to address all of these issues and may serve as a broad-spectrum antiviral to enhance host defense against a number of viral pathogens

A bona fide La protein is required for embryogenesis in Arabidopsis thaliana

Searches in the Arabidopsis thaliana genome using the La motif as query revealed the presence of eight La or La-like proteins. Using structural and phylogenetic criteria, we identified two putative genuine La proteins (At32 and At79) and showed that both are expressed throughout plant development but at different levels and under different regulatory conditions. At32, but not At79, restores Saccharomyces cerevisiae La nuclear functions in non-coding RNAs biogenesis and is able to bind to plant 3′-UUU-OH RNAs. We conclude that these La nuclear functions are conserved in Arabidopsis and supported by At32, which we renamed as AtLa1. Consistently, AtLa1 is predominantly localized to the plant nucleoplasm and was also detected in the nucleolar cavity. The inactivation of AtLa1 in Arabidopsis leads to an embryonic-lethal phenotype with deficient embryos arrested at early globular stage of development. In addition, mutant embryonic cells display a nucleolar hypertrophy suggesting that AtLa1 is required for normal ribosome biogenesis. The identification of two distantly related proteins with all structural characteristics of genuine La proteins suggests that these factors evolved to a certain level of specialization in plants. This unprecedented situation provides a unique opportunity to dissect the very different aspects of this crucial cellular activity

Arch Pediatr

BACKGROUND: Shaken baby syndrome (SBS) triggers negative short- and long-term outcomes. In France, registered childminders are the principal source of daycare. They may encounter SBS imparted by caregivers or simply excessive infant crying. The aim of the study was to explore childminder knowledge on SBS, the source of information, the responses to infant crying, how childminders perceived their roles in terms of caregiver SBS prevention, and the factors associated with a good knowledge of SBS. METHODS: The participants were registered childminders working in the French department of Gironde who had email accounts. This observational study employed an anonymous online questionnaire distributed by the maternal and child health services unit of the Gironde department over 5 weeks from 16 September 2021. Data on childminder characteristics, knowledge on SBS, responses to infant crying, and perceptions of their roles in SBS prevention were collected. The knowledge score ranged from 0 (all wrong answers) to 30 (all correct answers). RESULTS: A total of 779 registered childminders participated; 43.9 % had learnt about SBS during their initial training and 75 % before (other training) or after initial training. The median knowledge score was 19/30 (interquartile range [16; 21]). A higher educational level, previous other professional experience, training on SBS, and responsibility for few children were associated with higher scores. Ten reported that they did not advise caregivers who complained of infant crying. CONCLUSION: Childminders require training on SBS and SBS prevention

Peribiliary Gland Dilatation in Cirrhosis: Relationship with Liver Failure and Stem Cell/Proliferation Markers

Dilated peribiliary glands (PBG) in patients with cirrhosis are often an incidental finding although their significance and physiopathology remain unclear. We aimed to identify clinical factors associated with dilated PBG and to perform a detailed morphometric assessment of dilated PBG in cirrhotic patients undergoing liver transplantation (LT)

Arenavirus Nucleoprotein Targets Interferon Regulatory Factor-Activating Kinase IKKε.

Arenaviruses perturb innate antiviral defense by blocking induction of type I interferon (IFN) production. Accordingly, the arenavirus nucleoprotein (NP) was shown to block activation and nuclear translocation of interferon regulatory factor 3 (IRF3) in response to virus infection. Here, we sought to identify cellular factors involved in innate antiviral signaling targeted by arenavirus NP. Consistent with previous studies, infection with the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) prevented phosphorylation of IRF3 in response to infection with Sendai virus, a strong inducer of the retinoic acid-inducible gene I (RIG-I)/mitochondrial antiviral signaling (MAVS) pathway of innate antiviral signaling. Using a combination of coimmunoprecipitation and confocal microscopy, we found that LCMV NP associates with the IκB kinase (IKK)-related kinase IKKε but that, rather unexpectedly, LCMV NP did not bind to the closely related TANK-binding kinase 1 (TBK-1). The NP-IKKε interaction was highly conserved among arenaviruses from different clades. In LCMV-infected cells, IKKε colocalized with NP but not with MAVS located on the outer membrane of mitochondria. LCMV NP bound the kinase domain (KD) of IKKε (IKBKE) and blocked its autocatalytic activity and its ability to phosphorylate IRF3, without undergoing phosphorylation. Together, our data identify IKKε as a novel target of arenavirus NP. Engagement of NP seems to sequester IKKε in an inactive complex. Considering the important functions of IKKε in innate antiviral immunity and other cellular processes, the NP-IKKε interaction likely plays a crucial role in arenavirus-host interaction

DYRK1A-dosage imbalance perturbs NRSF/REST levels, deregulating pluripotency and embryonic stem cell fate in Down syndrome

Down syndrome (DS) is the most common cause of mental retardation. Many neural phenotypes are shared between DS individuals and DS mouse models; however, the common underlying molecular pathogenetic mechanisms remain unclear. Using a transchromosomic model of DS, we show that a 30%-60% reduced expression of Nrsf/Rest (a key regulator of pluripotency and neuronal differentiation) is an alteration that persists in trisomy 21 from undifferentiated embryonic stem (ES) cells to adult brain and is reproducible across several DS models. Using partially trisomic ES cells, we map this effect to a three-gene segment of HSA21, containing DYRK1A. We independently identify the same locus as the most significant eQTL controlling REST expression in the human genome. We show that specifically silencing the third copy of DYRK1A rescues Rest levels, and we demonstrate altered Rest expression in response to inhibition of DYRK1A expression or kinase activity, and in a transgenic Dyrk1A mouse. We reveal that undifferentiated trisomy 21 ES cells show DYRK1A-dose-sensitive reductions in levels of some pluripotency regulators, causing premature expression of transcription factors driving early endodermal and mesodermal differentiation, partially overlapping recently reported downstream effects of Rest +/-. They produce embryoid bodies with elevated levels of the primitive endoderm progenitor marker Gata4 and a strongly reduced neuroectodermal progenitor compartment. Our results suggest that DYRK1A-mediated deregulation of REST is a very early pathological consequence of trisomy 21 with potential to disturb the development of all embryonic lineages, warranting closer research into its contribution to DS pathology and new rationales for therapeutic approaches

A high-resolution anatomical atlas of the transcriptome in the mouse embryo.

Ascertaining when and where genes are expressed is of crucial importance to understanding or predicting the physiological role of genes and proteins and how they interact to form the complex networks that underlie organ development and function. It is, therefore, crucial to determine on a genome-wide level, the spatio-temporal gene expression profiles at cellular resolution. This information is provided by colorimetric RNA in situ hybridization that can elucidate expression of genes in their native context and does so at cellular resolution. We generated what is to our knowledge the first genome-wide transcriptome atlas by RNA in situ hybridization of an entire mammalian organism, the developing mouse at embryonic day 14.5. This digital transcriptome atlas, the Eurexpress atlas (http://www.eurexpress.org), consists of a searchable database of annotated images that can be interactively viewed. We generated anatomy-based expression profiles for over 18,000 coding genes and over 400 microRNAs. We identified 1,002 tissue-specific genes that are a source of novel tissue-specific markers for 37 different anatomical structures. The quality and the resolution of the data revealed novel molecular domains for several developing structures, such as the telencephalon, a novel organization for the hypothalamus, and insight on the Wnt network involved in renal epithelial differentiation during kidney development. The digital transcriptome atlas is a powerful resource to determine co-expression of genes, to identify cell populations and lineages, and to identify functional associations between genes relevant to development and disease