Immunogenic recombinant Mayaro virus-like particles present natively assembled glycoprotein.

Virus-like particles (VLPs) are an established vaccine platform and can be strong immunogens capable of eliciting both humoral and cellular immune responses against a range of pathogens. Here, we show by cryo-electron microscopy that VLPs of Mayaro virus, which contain envelope glycoproteins E1-E2 and capsid, exhibit an architecture that closely resembles native virus. In contrast to monomeric and soluble envelope 2 (E2) glycoprotein, both VLPs as well as the adenovirus and modified vaccinia virus Ankara (MVA) vaccine platforms expressing the equivalent envelope glycoproteins E1-E2, and capsid induced highly neutralising antibodies after immunisation.

Platelet Reactivity to Zika and Dengue Non-Structural Protein 1 (NS1) Assessed by Flow Cytometry, Atomic Force Microscopy, and Quartz Crystal Microbalance.

Background: Platelets, besides being traditionally associated with hemostasis, have been recently positioned as immune cells. Alterations in platelet number and function have been reported in some viral infections. Zika virus (ZIKV) and Dengue virus (DENV) are arboviruses that encode for a non-structural protein 1 (NS1).

Open architecture of archaea MCM and dsDNA complexes resolved using monodispersed streptavidin affinity CryoEM.

The cryo-electron microscopy (cryoEM) method has enabled high-resolution structure determination of numerous biomolecules and complexes. Nevertheless, cryoEM sample preparation of challenging proteins and complexes, especially those with low abundance or with preferential orientation, remains a major hurdle. We developed an affinity-grid method employing monodispersed single particle streptavidin on a lipid monolayer to enhance particle absorption on the grid surface and alleviate sample exposure to the air-water interface.

Dominant negative variants in ITPR3 impair T cell Ca2+ dynamics causing combined immunodeficiency.

The importance of calcium (Ca2+) as a second messenger in T cell signaling is exemplified by genetic deficiencies of STIM1 and ORAI1, which abolish store-operated Ca2+ entry (SOCE) resulting in combined immunodeficiency (CID). We report five unrelated patients with de novo missense variants in ITPR3, encoding a subunit of the inositol 1,4,5-trisphosphate receptor (IP3R), which forms a Ca2+ channel in the endoplasmic reticulum (ER) membrane responsible for the release of ER Ca2+ required to trigger SOCE, and for Ca2+ transfer to other organelles. The patients presented with CID, abnormal T cell Ca2+ homeostasis, incompletely penetrant ectodermal dysplasia, and multisystem disease.

Intra- and inter-subtype HIV diversity between 1994 and 2018 in southern Uganda: a longitudinal population-based study.

There is limited data on human immunodeficiency virus (HIV) evolutionary trends in African populations. We evaluated changes in HIV viral diversity and genetic divergence in southern Uganda over a 24-year period spanning the introduction and scale-up of HIV prevention and treatment programs using HIV sequence and survey data from the Rakai Community Cohort Study, an open longitudinal population-based HIV surveillance cohort. (p24) and (gp41) HIV data were generated from people living with HIV (PLHIV) in 31 inland semi-urban trading and agrarian communities (1994-2018) and four hyperendemic Lake Victoria fishing communities (2011-2018) under continuous surveillance.

Early Steps of Individual Multireceptor Viral Interactions Dissected by High-Density, Multicolor Quantum Dot Mapping in Living Cells.

Viral capture and entry to target cells are the first crucial steps that ultimately lead to viral infection. Understanding these events is essential toward the design and development of suitable antiviral drugs and/or vaccines. Viral capture involves dynamic interactions of the virus with specific receptors in the plasma membrane of the target cells.

Structure of the RNA-dependent RNA polymerase P2 from the cystovirus φ8.

The replication of RNA viruses relies on the activity of RNA-dependent RNA polymerases (RdRps). Despite large variations in their genomic sequences, viral RdRps share a common architecture generally known as a closed right hand. The P2 polymerase of cystovirus φ6 is currently among the best characterized viral RdRps.

POLR3B is associated with a developmental and epileptic encephalopathy with myoclonic-atonic seizures and ataxia.

Objective: POLR3B encodes the second largest subunit of RNA polymerase III, which is essential for transcription of small non-coding RNAs. Biallelic pathogenic variants in POLR3B are associated with an inherited hypomyelinating leukodystrophy. Recently, de novo heterozygous variants in POLR3B were reported in six individuals with ataxia, spasticity, and demyelinating peripheral neuropathy.

Zooming in and out: Exploring RNA Viral Infections with Multiscale Microscopic Methods.

RNA viruses, being submicroscopic organisms, have intriguing biological makeups and substantially impact human health. Microscopic methods have been utilized for studying RNA viruses at a variety of scales. In order of observation scale from large to small, fluorescence microscopy, cryo-soft X-ray tomography (cryo-SXT), serial cryo-focused ion beam/scanning electron microscopy (cryo-FIB/SEM) volume imaging, cryo-electron tomography (cryo-ET), and cryo-electron microscopy (cryo-EM) single-particle analysis (SPA) have been employed, enabling researchers to explore the intricate world of RNA viruses, their ultrastructure, dynamics, and interactions with host cells.

Oligomerization-driven avidity correlates with SARS-CoV-2 cellular binding and inhibition.

Cellular processes are controlled by the thermodynamics of the underlying biomolecular interactions. Frequently, structural investigations use one monomeric binding partner, while ensemble measurements of binding affinities generally yield one affinity representative of a 1:1 interaction, despite the majority of the proteome consisting of oligomeric proteins. For example, viral entry and inhibition in SARS-CoV-2 involve a trimeric spike surface protein, a dimeric angiotensin-converting enzyme 2 (ACE2) cell-surface receptor and dimeric antibodies.

Single-cell AI-based detection and prognostic and predictive value of DNA mismatch repair deficiency in colorectal cancer.

Testing for DNA mismatch repair deficiency (MMRd) is recommended for all colorectal cancers (CRCs). Automating this would enable precision medicine, particularly if providing information on etiology not captured by deep learning (DL) methods. We present AIMMeR, an AI-based method for determination of mismatch repair (MMR) protein expression at a single-cell level in routine pathology samples.

Relational Persistent Homology for Multispecies Data with Application to the Tumor Microenvironment.

Topological data analysis (TDA) is an active field of mathematics for quantifying shape in complex data. Standard methods in TDA such as persistent homology (PH) are typically focused on the analysis of data consisting of a single entity (e.g.

Clinical and genetic delineation of autosomal recessive and dominant ACTL6B-related developmental brain disorders.

Purpose: This study aims to comprehensively delineate the phenotypic spectrum of ACTL6B-related disorders, previously associated with both autosomal recessive and autosomal dominant neurodevelopmental disorders. Molecularly, the role of the nucleolar protein ACTL6B in contributing to the disease has remained unclear.

Methods: We identified 105 affected individuals, including 39 previously reported cases, and systematically analysed detailed clinical and genetic data for all individuals.

Indigenous-led precision public health: a new starting point.

Precision public healthcare has been applied to bring about positive change, narrowing the gap in healthcare inequity for Aboriginal peoples. Three such examples include the Mappa, Lyfe Languages, and Pilbra Faces projects, which were all developed through engagement and codesign with Indigenous Australians and each meet a distinct critical need. The Mappa project offers patients and healthcare providers with the necessary geographical information to navigate and maximally utilize available healthcare services.

Characterisation of infantile cardiomyopathy in Alström syndrome using ALMS1 knockout induced pluripotent stem cell derived cardiomyocyte model.

Alström syndrome (AS) is an inherited rare ciliopathy characterised by multi-organ dysfunction and premature cardiovascular disease. This may manifest as an infantile-onset dilated cardiomyopathy with significant associated mortality. An adult-onset restrictive cardiomyopathy may also feature later in life.

Noncoding variants are a rare cause of recessive developmental disorders in trans with coding variants.

Purpose: Identifying pathogenic noncoding variants is challenging. A single protein-altering variant is often identified in a recessive gene in individuals with developmental disorders (DD), but the prevalence of pathogenic noncoding "second hits" in trans with these is unknown.

Methods: In 4073 genetically undiagnosed rare-disease trio probands from the 100,000 Genomes project, we identified rare heterozygous protein-altering variants in recessive DD-associated genes.