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Iwasaki, M.

Publications and source records attributed to Iwasaki, M..

At least 19 recordsLinked to original sources

A bivalent Lassa virus mRNA vaccine protects guinea pigs from lethal infection with Lassa virus

Lassa virus (LASV), the causative agent of the life-threatening febrile disease, Lassa fever, remains a major public health concern in West Africa, where hundreds of thousands of infections occur annually. However, no licensed vaccine is currently available, highlighting the urgent need for effective preventive measures. We previously demonstrated that an mRNA-lipid nanoparticle (LNP) vaccine expressing LASV glycoprotein precursor (GPC; LASgpc-mRNA-LNP) conferred protection against lethal infection with a recombinant lymphocytic choriomeningitis virus expressing LASV GPC in mice. In this study, we extended our previous work with the aim of evaluating the efficacy of an mRNA-LNP vaccine expressing LASV nucleoprotein (NP; LASnp-mRNA-LNP) and a bivalent vaccine combining LASgpc-mRNA-LNP and LASnp-mRNA-LNP. Using a lethal CBA/N mouse model of infection with ML29, an LASV live-attenuated vaccine candidate encoding LASV GPC and NP, we found that LASgpc-mRNA-LNP and LASnp-mRNA-LNP each conferred protection in the absence of detectable neutralizing antibody responses. We identified LASV GPC- and NP-derived CD4 and CD8 T-cell epitope peptides in CBA/N mice and demonstrated that vaccination induced robust antigen-specific T-cell responses. Importantly, the bivalent vaccine provided complete protection against lethal challenge with doses at which monovalent vaccines failed to protect all mice, suggesting a potential dose-sparing benefit of the bivalent formulation. Furthermore, the bivalent vaccine fully protected guinea pigs against lethal challenge with authentic LASV. Together, these findings establish LASV NP, in addition to GPC, as a protective antigen in the mRNA vaccine platform and provide a rationale for developing bivalent mRNA-LNP vaccines to improve protection against Lassa fever.

microbiology↗

Spatial transcriptomics identifies L6 corticothalamic and L6b subplate-like heterotopic neurons in an epileptogenic SLC35A2-associated brain malformation.

Increased white matter (WM) heterotopic neurons are a pathological feature observed in various neurological and psychiatric disorders. Mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy (MOGHE) is a drug-resistant epilepsy-associated cortical malformation characterized by increased WM heterotopic neurons and OLIG2-positive cells and frequently associated with somatic SLC35A2 mutations. However, the precise cellular identity of these heterotopic neurons remains unclear. Using imaging-based spatial transcriptomics (iST) of SLC35A2-mutated MOGHE tissues, we found that most WM heterotopic neurons exhibited molecular signatures of excitatory neurons. Further analyses revealed that these heterotopic excitatory neurons included prominent populations with layer 6 corticothalamic (CT)-like and layer 6b subplate neuron (SpN)-like molecular features. These findings were further supported by human immunohistochemistry and a Slc35a2 conditional knockout (cKO) mouse model. Together, our results provide a cellular characterization of WM heterotopic neurons in MOGHE and suggest a new perspective on disease pathophysiology centered on deep-layer excitatory neuronal populations.

neuroscience↗

Hidden Structural Bias in Proteomics: Sonication-induced Selective Fragmentation of Intrinsically Disordered Regions

Sonication is a fundamental technique in proteome sample preparation, primarily used for protein solubilization and shearing of genomic DNA. Although the mechanical shearing of DNA is well-characterized, its unintended impact on protein structural integrity remains a significant "blind spot" in high-throughput analytical workflows. In this study, we systematically investigated sonication-induced protein fragmentation by combining gel-based fractionation (PEPPI-MS) with sequence-level compositional analysis and bioinformatic mapping. Our results demonstrate that sonication does not significantly alter overall proteome identification or the recovery of membrane proteins; however, it induces extensive and non-random protein fragmentation. Sonication caused an approximately three-fold increase in the abundance of >45 kDa protein-derived fragments migrating into the <40 kDa fraction, and 1,620 high-molecular-weight (MW) proteins were uniquely detected in the lower-MW fraction upon sonication, an eight-fold increase over non-sonicated controls. Peptide-level amino acid composition analysis revealed subtle but directional shifts in the sonication-derived fragments. This residue-level signature is reinforced by two orthogonal structural analyses (MobiDB peptide-level mapping and protein-level profiling using metapredict V3 software), which show that sonication-susceptible proteins harbor more than twice the disordered content of length-matched controls (median 40% vs. 18%). This study identifies a previously unrecognized "structural bias" whereby intrinsically disordered region (IDR)-rich proteins are selectively compromised during sample preparation. Because these fragments are indistinguishable from enzymatic digestion products in conventional bottom-up proteomics, the underlying structural damage is effectively masked in global quantitative datasets, potentially distorting biological interpretations related to protein size, isoforms, and stability, particularly for IDR-rich classes, such as transcription factors and signaling molecules. We propose that optimizing and standardizing sonication parameters is essential for ensuring the accuracy and reproducibility of quantitative proteomic analyses.

cell biology↗

Dysregulated flow responses drive pathogenesis in a cellular model of Sturge-Weber syndrome

Vascular diseases comprise a broad spectrum of conditions associated with organ dysfunction, yet how endothelial responses to mechanical forces drive their pathogenesis remains unclear. Sturge-Weber syndrome (SWS), a flow-associated vascular malformation caused by somatic GNAQ mutations, provides a model to investigate this question. Here, using isogenic induced pluripotent stem cell-derived endothelial cells (ECs), perfusable vascular models, and simplified systems under defined flow conditions, we show that SWS ECs exhibited maladaptive responses to laminar flow, including impaired flow alignment, reduced CLDN5 expression, and decreased transendothelial electrical resistance. Importantly, three-dimensional acoustic microscopy uncovered disturbed surface changes in SWS ECs, potentially contributing to changes in mechanosensing signaling. Transcriptomic and chromatin accessibility analyses revealed dysregulated flow-responsive gene programs, some of which were validated in human SWS samples. These findings provide insights into flow-dependent endothelial dysfunction and a framework for therapeutic modulation in SWS and other vascular disorders.

cell biology↗

Self-regenerating opsin from reef-building coral

Opsins underlie diverse physiological responses to light in animals. In the dark, most opsins bind the chromophore 11-cis retinal, which isomerizes to all-trans form upon light absorption, representing the initial key step in signaling. Maintenance of opsin function therefore requires continuous regeneration of the inactive, 11-cis-retinal-bound state. Here, we report a novel type of opsin, AtAntho2c, from a reef-building coral, whose active form, bound to all-trans retinal, can thermally revert to the initial dark state bound to 11-cis retinal. A cysteine residue in extracellular loop 2 region plays a key role in the self-regeneration ability. Using time-resolved and low-temperature spectroscopies, we identify two spectrally distinct photointermediates prior to the all-trans to 11-cis isomerization in AtAntho2c, whose formation rates and yields are found to vary depending on temperature and pH conditions. The active form of AtAntho2c activates Gi/o G protein, resulting in a transient and repeatable decrease in cellular cAMP levels upon repeated light stimulations, even in the absence of exogenous retinal in cultured cells. Furthermore, we confirm that cells expressing AtAntho2c exhibit membrane hyperpolarization via GIRK channel activation light-dependently. These properties highlight the potential of AtAntho2c as a versatile optogenetic actuator capable of repeatedly modulate Gi/o signaling without retinal supplementation. Significance StatementLight-sensitive proteins, opsins, form active states upon light absorption, leading to intracellular G protein signaling and various cellular outputs. The active states require specific enzymatic machinery or another photon absorption to regenerate inactive opsins ready to respond to repeated light stimuli and maintain continuous responsiveness. In our study, we identify and analyze a coral opsin of which the active state rapidly and autonomously reverts to the inactive state in the dark through thermal isomerization of the retinal chromophore within the opsin. This regeneration mechanism allows the opsin to respond to repeated light stimuli at high temporal resolution and maintain large signal amplitude without the need for exogenous retinal making this opsin potentially useful for developing versatile optogenetic tools.

biophysics↗

Human club cells derived from pluripotent stem cells reveal new insights into epithelial lineage plasticity through structural and functional validation

Airway epithelial homeostasis relies on multiple specialized cell types, with club cells playing central roles in maintaining epithelial integrity and regulating inflammation. Environmental insults such as allergens, viral infections, or pollutants preferentially damage club cells, impairing epithelial repair and contributing to pulmonary diseases. However, the functional properties of club cells remain incompletely defined, and tractable human models are lacking. Herein, we establish a robust platform to differentiate human pluripotent stem cells (hPSCs) into club cells exhibiting their hallmark secretory features, appropriate epithelial organization, and functional properties. Single-cell transcriptomic analyses and lineage trajectory inference revealed unexpected epithelial plasticity: hPSC-derived club cells give rise to multiciliated epithelial cells through a deuterosomal intermediate--a previously uncharacterized trajectory. Additionally, a distinct club cell subset exhibited transcriptional features indicative of neuroendocrine and goblet cell differentiation potential. This study uncovers club cell plasticity and establishes a hPSC-based platform for studying airway development, regeneration and disease modeling.

cell biology↗

Chromatin landscape and epigenetic heterogeneity of acute myeloid leukemia

Acute myeloid leukemia (AML) is an aggressive hematologic cancer characterized by proliferation of immature myeloblasts. It shows profound molecular heterogeneity, which has been primarily studied through genetic abnormalities, providing the basis for disease classification, prognostication, and therapeutic choice. However, genetic factors alone may not fully explain AML pathogenesis and diversity, while leaving the role of abnormal epigenome, particularly chromatin state, largely unexplored in a large cohort of patients. Here we show that AML is classified into 16 subgroups with distinct chromatin accessibility profiles based on ATAC-seq in 1,563 AML cases, including novel AML subgroups not previously recognized in conventional genomic classifications. By integrating multi-omics analyses of genome, transcriptome, and major histone marks, we show that these epigenetic subgroups exhibit unique features in clinical presentation, gene mutations, differentiation states, gene expression, and super-enhancer profiles, which are validated across independent cohorts. Single-cell sequencing demonstrates the presence of subgroup-specific ATAC signatures that are shared by all leukemic cells, confirming the definitive role of the epigenome in the ATAC-based classification. Mechanistically, each subgroup is associated with a distinct gene regulatory network centered on key transcription factors, where subgroup-specific super-enhancers play a pivotal role. These ATAC subgroups also have prognostic significance independent of genomic classification, and help reveal unexpected drug sensitivities. In summary, ATAC-based chromatin profiling in this large sample set, combined with multi-omics data, provides new insights into AML pathogenesis beyond genomic profiling and also serves as an invaluable resource for AML research.

cancer biology↗

Comprehensive transcriptomic and proteomic profiling of mTOR-related epilepsy

Malformations of cortical development (MCDs) are a major cause of drug-resistant epilepsy (DRE) in children. A subset of MCDs, including focal cortical dysplasia type II, tuberous sclerosis complex, and hemimegalencephaly, shares characteristic histopathological features and somatic mutations in genes within the PI3K-AKT-mTOR signaling cascade, and is termed mTORopathies. However, the molecular mechanisms that drive epileptogenesis and consequent uncontrollable seizures in these disorders remain poorly understood. Here, we performed integrated genomic, transcriptomic, and proteomic analyses of 60 surgical brain specimens from 42 patients with MCDs and 18 with mesial temporal lobe epilepsy. Targeted genomic sequencing identified 19 somatic mutations in PI3K-AKT-mTOR pathway genes, including novel variants in AKT3 (L51H) and MTOR (A512T). RNA sequencing comparing mTORopathy brains with controls, along with cross-validation using an independent public dataset, identified 287 consistently differentially expressed genes that were consistently altered. Downregulated genes were enriched in oxidative phosphorylation (OXPHOS) and mitochondrial metabolic pathways, whereas upregulated genes were associated with gliogenesis and cellular senescence. Proteomic profiling identified 44 differentially expressed proteins, including significant reductions in OXPHOS-related proteins (COX5B, NDUFS4, GOT2, RAB27B, and DKK3). Our study provides a patient-matched, multi-omics dataset of human mTOR-related epilepsies from a single-institution cohort. Integrated analyses across transcriptomic and proteomic layers highlight impairment of OXPHOS as a molecular hallmark of mTORopathies, Integrated transcriptomic and proteomic analyses identified impaired OXPHOS as a molecular hallmark, potentially contributing to focal hypometabolism in mTORopathy. These findings offer mechanistic insights into epileptogenesis and provide a valuable resource for understanding molecular pathologies and developing mechanism-based therapies for mTOR-related epilepsy.

neuroscience↗

Single-cell-resolved spatial multi-omics identifies mTOR-driven neuronal and astroglial pathogenicity underlying epileptogenic focal cortical dysplasia

Focal cortical dysplasia type II (FCDII) is a malformation of cortical development caused by somatic mutations in the mTOR signaling pathway. Two hallmark pathological cell types in FCDII, dysmorphic neurons (DNs) and balloon cells (BCs), arise as a result of somatic mutations in the mTOR signaling pathway and are implicated in the pathophysiology of drug-resistant epilepsy. However, how these somatic mutations reshape cell states within the human cortex remains poorly understood. Here, we integrate imaging-based spatial transcriptomics (iST), single-nucleus RNA sequencing, and proteomics of surgically resected FCDIIb tissue to define the transcriptional and proteomic profiles of DNs and BCs. Spatial mapping of iST data resolved transcriptional signatures in histologically validated DNs and BCs within FCDIIb sections. Integrative omics analysis further revealed that DNs show upregulation of PI3K-AKT-mTOR and p53-CROT metabolic programs accompanied by suppression of synaptic signaling, whereas BCs exhibit transcriptional signatures of reactive astrocytes with increased phagocytic and immune-like activity. These data delineate cell-type-specific consequences of somatic mTOR pathway mutations at single-cell resolution and reveal previously unrecognized metabolic and immunoregulatory mechanisms contributing to epileptogenesis in drug-resistant epilepsy. Our study establishes a spatial multi-omics framework for dissecting human cortical malformations and highlights potential therapeutic targets for drug-resistant epilepsy.

neuroscience↗

In vivo xenogenic reconstitution of human alveolar epithelial architecture and function

An urgent need exists for lung models that accurately replicate human physiological profiles. We developed a chimeric mouse model enabling targeted ablation of alveolar type 2 (AT2) cells and lung macrophages, creating niches for endoscopically transplanted human induced pluripotent stem cell (hiPSC)-derived lung progenitors (hLPs). These engrafted cells were retained for 24 weeks, demonstrating self-renewal and differentiation potential, surfactant protein secretion, and maintaining alveolar phosphate homeostasis, suggesting their maturation into AT2 cells. Furthermore, transplantation of hLPs derived from disease-specific hiPSCs recapitulated the phenotype of pulmonary alveolar microlithiasis. The architecture, function, and metabolism of human alveolar epithelium were accurately replicated in vivo. This model has the potential to link experimental models and first-in-human studies, facilitating the development of novel therapies for intractable lung diseases.

developmental biology↗

eIF4G2-Mediated Translation Initiation of Histone Modifiers Is Essential for Intestinal Stem Cell Maintenance and Differentiation

eIF4G2 (also known as NAT1, p97, or DAP5) is an evolutionally conserved protein homologous to the C-terminal two-thirds portion of eukaryotic translation initiation factor (eIF) 4G. Despite its abundant and ubiquitous expression, the physiological and pathological functions of eIF4G2 are poorly understood. Here, we show that acute loss of eIF4G2 in adult mice results in rapid weight loss with abnormalities in multiple organs, including impaired maintenance and differentiation of intestinal stem cells. Genome-wide ribosome profiling revealed that eIF4G2 is critical for the translation of key histone modification proteins involved in intestinal stemness. Our study underscores the importance of eIF4G2-mediated translation initiation in multicellular organisms.

cell biology↗

Visualization of functional and effective connectivity underlying auditory descriptive naming

ObjectiveWe visualized functional and effective connectivity within specific white matter networks in response to auditory descriptive questions. MethodsWe investigated 40 Japanese-speaking patients with focal epilepsy and estimated connectivity measures using cortical high-gamma dynamics and MRI tractography. ResultsHearing a wh-interrogative at question onset enhanced inter-hemispheric functional connectivity, with left-to-right callosal facilitatory flows between the superior-temporal gyri, contrasted by functional connectivity diminution with right-to-left callosal suppressive flows between dorsolateral prefrontal regions. Processing verbs associated with concrete objects or adverbs increased left intra-hemispheric connectivity, with bidirectional facilitatory flows through extensive white matter pathways. Questions beginning with what, compared to where, induced greater neural engagement in the left posterior inferior-frontal gyrus at question offset, linked to enhanced functional connectivity and bidirectional facilitatory flows to the temporal lobe neocortex via the arcuate fasciculus. During overt responses, inter-hemispheric functional connectivity was enhanced, with bidirectional callosal flows between Rolandic areas, and individuals with higher IQ scores exhibited less prolonged neural engagement in the left posterior middle frontal gyrus. ConclusionsVisualization of directional neural interactions within white matter networks during overt naming is feasible. SignificancePhrase order may influence network dynamics in listeners, even when presented with auditory descriptive questions conveying similar meanings.

neuroscience↗

Coral anthozoan-specific opsins employ a novel chloride counterion for spectral tuning

Animal opsins are G protein coupled receptors that have evolved to sense light by covalently binding a retinal chromophore via a protonated (positively charged) Schiff base. A negatively charged amino acid in the opsin, acting as a counterion, stabilizes the proton on the Schiff base, which is essential for sensitivity to visible light. In this study, we investigate the spectroscopic properties of a unique class of opsins from a reef-building coral belonging to the anthozoan-specific opsin II group (ASO-II opsins), which intriguingly lack a counterion residue at any of established sites. Our findings reveal that, unlike other known animal opsins, the protonated state of the Schiff base in visible light-sensitive ASO-II opsins is highly dependent on exogenously supplied chloride ions (Cl-). By using structural modelling and QM/MM calculations to interpret spectroscopy data, we conclude that, in the dark state, ASO-II opsins employ environmental Cl- as their native counterion, while a nearby polar residue, Glu292 in its protonated neutral form, facilitates Cl- binding. In contrast, Glu292 plays a crucial role in maintaining the protonation state of the Schiff base in the light-activated protein, serving as the counterion in the photoproduct. Furthermore, Glu292 is involved in G protein activation of the ASO-II opsin, suggesting that this novel counterion system coordinates multiple functional properties.

biophysics↗

Temperature-dependent polar lignification of a seed coat suberin layer promoting dormancy in Arabidopsis thaliana

The seed is a landmark plant adaptation where the embryo is sheltered by a protective seed coat to facilitate dispersion. In Arabidopsis, the seed coat, derived from ovular integuments, plays a critical role in maintaining dormancy, ensuring germination occurs during a favorable season. Dormancy is enhanced by cold temperatures during seed development by affecting seed coat permeability through changes in apoplastic barriers. However, the localization and composition of these apoplastic barriers are poorly understood. This study identifies and investigates a polar barrier in the seed coats outer integument (oi1) cells. We present histological, biochemical, and genetic evidence showing that cold promotes polar seed coat lignification of the outer integument 1 (oi1) cells and suberization throughout the entire oi1 cell boundary. The polar oi1 barrier is regulated by the transcription factors MYB107 and MYB9. MYB107, in particular, is crucial for the lignified polar oi1 barrier formation under cold temperatures. The absence of the oi1 barrier in mutant seeds correlates with increased permeability and reduced dormancy. Our findings elucidate how temperature-induced modifications in seed coat composition regulate dormancy, highlighting the roles of suberin and lignin in this process. Significance statementOur study uncovers how cold temperatures during seed development in the mother plant influence seed dormancy through apoplastic modifications in the Arabidopsis thaliana seed coat. We identified a polar lignin barrier in the outer integument 1 (oi1) cells, which are also suberized. Lignification and suberization are regulated by transcription factors MYB107 and MYB9. Cold promotes lignification and suberization of oi1 cells through MYB107, thus creating a "memory" that reduces seed permeability and strengthens dormancy. Mutants defective in the oi1 barrier exhibit lower dormancy, highlighting the adaptive importance of this barrier. These findings advance our understanding of temperature-induced seed coat adaptations and their agricultural implications, particularly in the context of climate change, offering valuable insights for improving crop resilience and yield.

plant biology↗

Method for Spatially Confined Stimulation by Retinal Scanning Displays: Are Blind Spots Really Blind?

Conventional displays, such as CRTs and LCDs, are commonly used to present and manipulate visual stimuli in many vision science studies. However, such displays pose difficulties when the goal is to constrain stimulation to specific retinal locations, so as to isolate their contribution to downstream effects. Scattered and refracted light can stimulate unintended areas, contaminating the outcomes. In this investigation, we evaluate a laser-based retinal scanning display for its ability to map and exclusively stimulate the retinal blind spot. This application stimulates melanopsin receptors inside the blind spot, separately from rod and cone photoreceptors, which lie outside the blind spot. This paper covers three experiments: 1. The initial exploratory observations; 2. the examination of pupillary responses, and; 3. the inference of implicit visual perception arising from the blind spot. We aimed to simultaneously validate our technical methods, while increasing our understanding of the role of melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) in vision and implicit visual perception.

neuroscience↗

A hybrid combination of in vitro cultured buccal mucosal cells using two different methodologies, complementing each other in successfully repairing a stricture-inflicted human male urethral epithelium

BackgroundAutologous buccal mucosal tissue derived cell transplantation techniques in repairing a stricture inflicted male urethral epithelium have been evolving. There was not much of clarity on the cell type, in vitro culture methods and the mode of transplantation, until we reported our buccal epithelium expanded and encapsulated in scaffold-hybrid approach to urethral stricture (BEES-HAUS) clinical study yielding a successful engraftment and repair with a long-term patency. We herein report with technical clarity on the advantages of mixing two-dimensional (2D) monolayer cultured fibroblast like cells and three dimensional (3D) thermo-reversible gelation polymer (TGP) cultured cells; the former secreting IGF-1, a cytokine known for its healing effects and the latter expressing epithelial surface markers in flow cytometry, both sourced from human buccal tissue, together transplanted using TGP as a carrier. MethodsHuman buccal tissues (n=22) redundant after urethroplasty surgery was used after informed consent and IEC approval. They were enzyme digested, divided into two portions; one was cultured as monolayer method (2D) and the other in 3D in TGP. Flowcytometry and quantification of IGF-1 in cell culture supernatant through the culture period were undertaken. ResultsIn flowcytometry, the cells on day 0, lacked AE1/AE3 - pancytokeratin expression indicative of epithelial phenotype of culture, which progressively increased in the 3D-TGP group, during invitro culture of up to 21 days. The 2D showed expression of only fibroblasts like cells that were negative for AE1/AE3 but positive for CD140b. IGF-1 secretion was significantly higher in 2D cultures than in 3D-TGP (p-value < 0.05). ConclusionThe 3D- TGP cultured cells of epithelial nature and the 2D cultured fibroblast like cells secreting IGF-1, together when transplanted using TGP scaffold as a carrier, adapted to a hostile in vivo milieu after releasing the fibrous strands with urethrotomy, successfully engrafted and repaired a stricture-inflicted male urethral epithelium in the BEES-HAUS procedure. While this hybrid combination of cells are considered to have potential in managing other epithelial damages, further research of such hybrid combination and their behaviour in disease affected environments may help to expand this solution in regenerating and repairing other tissues and organs as well. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=123 SRC="FIGDIR/small/555240v1_ufig1.gif" ALT="Figure 1"> View larger version (70K): org.highwire.dtl.DTLVardef@1e00b7eorg.highwire.dtl.DTLVardef@12886aorg.highwire.dtl.DTLVardef@b9fbb3org.highwire.dtl.DTLVardef@3bd247_HPS_FORMAT_FIGEXP M_FIG C_FIG Illustration of pathogenesis of urethral stricture and the contribution of the hybrid combination of two-dimensional (2D) and three dimensional, 3D-TGP (Thermo-reversible gelation polymer) cultured cells to the successful repair of the stricture-inflicted male urethral epithelium in the buccal epithelium expanded and encapsulated in scaffold-hybrid approach to urethral stricture (BEES-HAUS) technique.

synthetic biology↗

Enhanced muscle regeneration in mdx mice, Duchenne muscular dystrophy animal model, proven by CD44 & MYH3 expression, on oral feeding of N-163 strain of Aureobasidium Pullulans produced B-Glucan

IntroductionDuchenne muscular dystrophy (DMD) is a rare genetic disease, causing muscle degeneration due to lack of dystrophin with inadequate muscle regeneration culminating in muscle dysfunction. The N-163 strain of Aureobasidium Pullulans produced Beta-1,3-1,6-glucan (Neu REFIX) reported to be safe with anti-inflammatory and anti-fibrotic efficacy earlier, herein we evaluated its effects on muscle regeneration in mdx mice. MethodsForty-five mice in three groups (n=15 each): Group 1 (normal), Group 2 (mdx control), and Group 3 (mdx fed Neu REFIX) were evaluated for 45 days. IGF-1, Dystrophin, CD44 and MYH3 in diaphragm, plasma and skeletal muscle were evaluated by ELISA and immunohistochemistry. ResultsMean IGF-1 expression was 20.32% and 16.27% higher in plasma (p = 0.03) and diaphragm respectively in Neu-REFIX group. Mean dystrophin was higher in Neu-REFIX group by 70.3% and 4.7% in diaphragm and plasma respectively than control. H-score intensity of CD44+ was >2.0 with an MYH3-positivity 20% higher in Neu-REFIX than control. ConclusionOral administration of Neu REFIX was safe. Significantly enhanced plasma IGF-1 beside increased Dystrophin, MYH3 and CD44, proving a restoration of muscle regeneration and differentiation, especially in diaphragm, makes us recommend it as a disease modifying adjuvant in both early and advanced stages of DMD.

genetics↗

An mRNA-LNP-based Lassa virus vaccine induces protective immunity in mice

The mammarenavirus Lassa virus (LASV) causes the life-threatening hemorrhagic fever disease, Lassa fever. The lack of licensed medical countermeasures against LASV underscores the urgent need for the development of novel LASV vaccines, which has been hampered by the requirement for a biosafety level 4 facility to handle live LASV. Here, we investigated the efficacy of mRNA-lipid nanoparticle (mRNA-LNP)-based vaccines expressing the LASV glycoprotein precursor (LASgpc) or the nucleoprotein (LCMnp) of the prototypic mammarenavirus, lymphocytic choriomeningitis virus (LCMV), in mice using recombinant (r) LCMV expressing a modified LASgpc and wild-type rLCMV. Two doses of LASgpc- or LCMnp-mRNA-LNP administered intravenously or intramuscularly protected mice from a lethal challenge with rLCMVs. Negligible levels of LASgpc-specific antibodies were induced in mRNA-LNP-immunized mice, but robust LASgpc- and LCMnp-specific CD8+ T cell responses were detected. Our findings and surrogate mouse models of LASV infection provide a critical foundation for the rapid development of mRNA-LNP-based LASV vaccines.

microbiology↗