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Guan, S.

Publications and source records attributed to Guan, S..

At least 19 recordsLinked to original sources

Simultaneous multi-area recordings in macaque frontoparietal cortex during a manual object-interaction task

Dexterous hand control is essential for daily activities and a top restoration priority for people with tetraplegia, yet neurophysiological datasets suitable for studying and decoding naturalistic hand behavior remain scarce. Most available recordings constrain movements to a small number of degrees of freedom or cover only a single stereotypical grasp-and-hold structure. Moreover, previous brain-computer interface (BCI) studies have largely relied on signals from a single cortical area, even though dexterous hand control is distributed across an interconnected frontoparietal network. To address these limitations, we designed a paradigm that elicits rich hand movements across 40 distinct hand-object interaction conditions. We recorded simultaneous frontoparietal activity with hand kinematics from a rhesus macaque performing them. Neural activity was recorded from the primary motor cortex, anterior intraparietal area, and ventral premotor cortex using microelectrode arrays spanning 1,920 channels, while a multi-camera markerless motion-capture system acquired video from which kinematics were extracted offline. The dataset comprises data from 20 sessions, including processed neural features, synchronized 3D coordinates of hand and elbow keypoints, and trial-level metadata including task conditions and event timing. We further provide technical validation, including a neural decoding benchmark with multiple algorithms for continuous keypoint coordination reconstruction. We found that cross-day and cross-task decoding performance varied among algorithms. Variation in channel availability leads to different performance degradation curves in different algorithms. This task-rich dataset offers a valuable resource for investigating the neural mechanisms of dexterous hand control and for advancing the performance of motor BCIs.

neuroscience↗

Ileal Gpbar1 gates depressive phenotypes via gut to brain "vagal-NTS-PVN"GABAergic axis

Depression represents a typical mental condition, yet whether intestinal metabolic signals drive central neural circuits remains unclear. Here we identify ileal enteric neuronal Gpbar1 as a previously unrecognized peripheral node that coordinates gut-to-brain communication to prevent depression-like behavior through a vagus-dependent, nucleus tractus solitaries (NTS)-paraventricular nucleus (PVN) signaling axis. The enteric plexus Gpbar1 is predominantly expressed on a subpopulation of GAD1-positive GABAergic neurons. Chronic restraint stress suppresses Gpbar1 expression, triggers glycolytic reprogramming and mitochondrial distress in both ileum and hypothalamus. Oral Gpbar1 agonism with INT-777 reverses hypothalamic HK2/TOM20 alterations and behavioral abnormalities by enhanced ileal mTOR/HIF-1 alpah signaling and glycolysis-related metabolite shifts, an effect specifically abolished by subdiaphragmatic vagotomy or chemogenetic silencing of PVN GABAergic neurons. Our findings establish ileal Gpbar1 as a gut-derived metabolic sensor that engages a defined vagal-brainstem-hypothalamic inhibitory circuit to regulate depressive phenotypes, shifting the roadmap from brain-centered to gut-initiated antidepressant mechanisms and unveiling a compelling peripheral therapeutic strategy that bypasses intractable central brain-directed intervention.

neuroscience↗

Deoxyribonucleotide incorporation reshapes mRNA design beyond canonical ribonucleotide boundaries

Messenger RNA (mRNA) is canonically composed of ribonucleotides, with sporadic incorporation of deoxyribonucleotides into natural RNA transcripts being traditionally regarded as a rare, deleterious error arising from transcriptional infidelity. Here, we challenge this paradigm by demonstrating controlled partial substitution of ribonucleotides with deoxyribonucleotides during in vitro transcription (IVT) generates intact, stable and fully translationally competent IVT-mRNA. Unexpectedly, chimeric DNA-RNA backbone modification exhibits markedly enhanced IVT-mRNA translation several fold across multiple cell types and in vivo via diverse dosing routes relative to their ribonucleotide-based counterparts. 25% substitution of cytidine triphosphate with deoxycytidine triphosphate achieved best-performing translational output, surpassing the current gold-standard N1-methylpseudouridine (m1{Psi})-modified IVT-mRNA in a B16-OVA tumor vaccination model. These findings identify nucleotide class composition as a previously unrecognized parameter governing IVT-mRNA function and establish hybrid ribonucleotide-deoxyribonucleotide backbone engineering as a versatile strategy to expand the chemical space for next-generation mRNA therapeutics.

synthetic biology↗

An oncolytic adenovirus armed with anticancer prodrug-activating enzyme offers enhanced tumor killing and antitumor immunity.

Oncolytic viruses are most commonly administered via intratumoral injection; however, their clinical efficacy in achieving tumor eradication remains limited by several challenges, including insufficient penetration into all tumor cells and the inability to elicit robust systemic antitumor immune responses capable of eliminating metastatic microtumors. Here, we report an oncolytic adenovirus, OAd-2B6, with an engineered adenoviral E1 region for tumor selectivity and carrying the prodrug- activating enzyme cytochrome P450 2B6 (CYP2B6) to activate the anticancer prodrug cyclophosphamide (Cytoxan, CTX). OAd-2B6 alone induced dose-dependent tumor cell killing across multiple human tumor cell lines and exhibited strong synergistic antitumor effects when combined with CTX. Importantly, OAd-2B6-mediated local activation of CTX resulted in a potent bystander killing effect that eliminated tumor cells not directly infected by the virus. In a H1299 lung cancer xenograft nude mouse model, intratumoral injection of OAd-2B6 combined with CTX significantly inhibited tumor growth and even achieved complete tumor regression, with markedly superior efficacy compared with monotherapy. In immunocompetent mice bearing 4T1 breast cancer xenografts, OAd-2B6 alone inhibited tumor growth and was accompanied by upregulation of IFN-{gamma} and GzmB expression in the tumor-infiltrated T cells. CTX combination therapy further enhances this anti-tumor immune response, promoting the activation of T cells to suppress non-injected tumors at a distal site. Collectively, this study demonstrates that OAd-2B6 exerts potent antitumor effects through multiple mechanisms, including direct oncolysis, intratumoral prodrug activation leading to bystander killing, and enhancement of systemic antitumor immunity. These findings provide a promising strategy for improving the therapeutic efficacy of oncolytic therapy.

cancer biology↗

WTR: A Toolkit for Functional Anterograde Transsynaptic Circuit Mapping

The brain coordinates animal physiology and behavior via neuronal circuits. To understand and simulate brain functions, it is essential to delineate the synaptic connectivity between neurons. Transsynaptic tracers serve as powerful tools for such purposes. In response to the demand for anterograde tracers for circuit mapping and functional interrogation, we developed WTR, a fusion protein of mammalian codon-optimized WGA, TEV-protease cleavage sequence, and Recombinase. WTR expressed via AAV vectors in cell-type-specific starter neurons reaches their postsynaptic neurons and releases Cre/Flpo upon exposure to TEV-protease expressed in downstream neurons. Accompanied by Cre/Flpo-dependent expression of EGFP, GCaMP7s, or ChR2, the toolkit enables labeling, recording, or manipulation of downstream neurons. We utilized WTR to characterize downstream neurons of either glutamatergic or GABAergic neurons in the preoptic area of anterior hypothalamus for their differential actions in thermoregulation or stress responses, respectively. These results establish WTR as a versatile platform for functional anterograde circuit mapping.

neuroscience↗

Host Microenvironment Reprogramming by Saccharides Overcomes Lung Barriers for mRNA Therapeutics

AbstractOvercoming biological barriers remains the paramount challenge for pulmonary mRNA therapeutics. Conventional approaches focus exclusively on passively optimizing formulation quality without controlling dynamic host barriers. Here, we pioneer a host-centric strategy by leveraging sugar that actively reprograms the airway microenvironment to boost IVT-mRNA transfection. Utilizing machine learning-accelerated screening of a chemically diverse saccharide library, we identify D-glucose as the best-performing candidate. Glucose assisted-delivery within lipid nanoparticles (Glu-LNP) achieves robust, lung-specific protein expression (up to 131.21-fold increase) across diverse preclinical models with reduced inflammation. In lung carcinoma models, Glu-LNP-encapsulated IL-12 mRNA reduced tumor burden by approximately 59.12% and improved survival by 2.5-fold compared to the LNP group. Mechanistically, glucose orchestrates a dual-pathway cascade: metabolic reprogramming via the Warburg effect elevates ATP, fueling endocytosis and translation; ATP further activates the P2Y2-IP3 signaling axis that triggers Ca2+ release and subsequent CLCA1/TMEM16A-dependent chloride/bicarbonate efflux, which remodels mucus barriers and enhances nanoparticle penetration. This bioenergetic and mucolytic host intervention strategy presents a broadly applicable paradigm to transcend delivery limitations for respiratory mRNA therapeutics.

bioengineering↗

Advancing Inter-brain Synchrony Measurement: A Comparative Hyperscanning Study of High-Density Diffuse Optical Tomography and Functional Near-infrared Spectroscopy

Inter-brain synchrony (IBS), measured by hyperscanning, refers to the synchronization of multiple individuals brain activities during social interactions. Traditional fNIRS-based hyperscanning suffers shortcomings like low spatial resolution and high susceptibility to superficial interference, causing imprecise estimation of IBS in complex social tasks. This study aims to fill the knowledge gap by comprehensively assessing how high-density diffuse optical tomography (HD-DOT), an enhanced alternative to fNIRS, can benefit hyperscanning studies of complex social interactions. Sixteen dyads were engaged in both collaborative and individual tangram puzzle tasks, and their brain activities were recorded simultaneously using HD-DOT and fNIRS. We found that HD-DOT demonstrated significantly stronger IBS and identified more brain regions with significant IBS compared to fNIRS during the collaborative task. Specifically, while fNIRS detected IBS only in the dorsolateral prefrontal cortex (DLPFC) and supramarginal gyrus (SMG), HD-DOT revealed additional IBS in the superior temporal gyrus (STG). Additionally, compared to the individual task, the collaborative task showed increased IBS in HD-DOT, not only in the DLPFC but also in the SMG, frontal eye fields (FEF), and inferior frontal gyrus (IFG). By highlighting the superior spatial resolution and sensitivity of HD-DOT in capturing detailed and extensive neural activity during complex social interactions, our findings for the first time clarified the potential strengths of HD-DOT in measuring IBS over traditional fNIRS. These advances provide a stronger empirical foundation for investigating the neural basis of social interaction, paving the way for future research on real-world, dynamic group behaviors. HighlightsO_LIFirst application of HD-DOT for inter-brain synchrony measurement. C_LIO_LIFirst demonstration of HD-DOTs superiority over fNIRS in IBS measurement. C_LIO_LIHD-DOT detects stronger IBS and more brain regions than fNIRS. C_LI

neuroscience↗

Modular Inter-brain Synchrony Network Associated with Social Difficulty in Autism Spectrum Disorder: a Graph Neural Network-Driven Hyperscanning Study

Understanding social difficulties in Autism Spectrum Disorder (ASD) remains challenging due to its neurobiological heterogeneity and the limited ecological validity of conventional neuroimaging methods in capturing dynamic social interactions. Hyperscanning analysis based on functional near-infrared spectroscopy (fNIRS), which measures inter-brain synchrony (IBS) during dyadic interaction, offers a novel avenue to address these challenges. However, prior studies on ASD have reported inconsistent findings, primarily focusing on intra-regional synchronization while overlooking cross-regional network dynamics. To bridge this gap, we proposed an interpretable graph neural network (GNN) model to systematically identify ASD-specific IBS modular network between child-caregiver dyads during naturalistic cooperative puzzle-solving and free-talking tasks. We identified distinctive key IBS sub-networks for the cooperative puzzle-solving task and free-talking task, with the frontal eye field (FEF) of caregivers, the dorsal lateral prefrontal cortex (DLPFC) and the motor region of children highlighted. Furthermore, the key IBS sub-networks were found to be able to predict multiple domains of the core ASD symptoms. By integrating hyperscanning with GNN-driven analysis, this work uncovers task-dependent inter-brain neural mechanisms underlying social difficulties in ASD. These findings advance the field by proposing a data-driven framework to identify IBS biomarkers tied to clinical profiles, paving the way for personalized interventions that integrate computational neuroscience with clinical practice.

neuroscience↗

Meta-AlignNN: A meta-learning framework for stable brain-computer interface performance across subjects, time, and tasks

Practical application of brain-computer interfaces (BCIs) requires stable mapping between neuronal activity and behavior through various behavioral contexts and for different individuals. Due to neural activity instability, BCIs require frequent recalibration to maintain robust performance. Early approaches to addressing BCI stability issues mainly focused on tackling the challenge of neural activity changes over time. However, future BCI applications involve diversified scenarios and subjects, requiring solutions that address neural variability across time, subjects, and tasks. This study proposes a meta-learning-based algorithm to achieve BCI stability, named "Meta-AlignNN." By capitalizing on the consistency of neural population dynamics, it provides a unified solution for maintaining BCI stability, robustness, and scalability across subjects, time, and tasks. Tested over two years on four tasks with three monkeys, as well as on public datasets, the approach has achieved significantly excellent performance in both offline decoding and real-time brain-control, outperforming existing methods. Our findings provides a foundation for meeting the clinical demands of longterm, efficient, and stable usability across patients and tasks, offering a compelling solution for practical BCI applications.

bioengineering↗

Optical Phenotyping Using Label-Free Microscopy and Deep Learning

SignificanceTissue phenotyping plays a critical role in biomedical research and clinical applications by providing insight into the structural and functional characteristics of tissues that can characterize clinical behavior and identify therapeutic targets. However, conventional phenotyping techniques are destructive, time-intensive, and expensive, posing challenges for both efficiency and widespread use. AimTo develop an optical phenotyping approach in pancreatic cancer specimens using label-free multiphoton microscopy combined with spatial transcriptomics and deep learning. ApproachWe measure and co-register a dataset comprised of spatial transcriptomics, autofluorescence, and second harmonic generation microscopy. We then cluster tissue subregions into meaningful phenotypes using transcriptomic signatures. We then evaluate three different classification models to predict phenotype based on label-free imaging data, and assess generalizability and prediction accuracy. ResultOur deep-learning classification model achieves over 89% accuracy in classifying six tissue types using label-free microscopy images. The one-vs-rest AUC values for all classes approaches 1, confirming the robustness of our model. ConclusionWe demonstrate the feasibility of optical phenotyping in distinguishing the structural and functional characteristics of pancreatic cancer specimens. Integrating additional gene-expression data or complementary label-free imaging modalities, such as fluorescence lifetime imaging microscopy, holds the potential to further enhance its accuracy and expand its applications in clinical research and diagnostics. Statement of DiscoveryWe develop and demonstrate a method for optical phenotyping using deep learning to classify label-free microscopy images into tissue phenotypes defined by transcriptomic signatures.

bioengineering↗

Characterizing the Microbiome of 'Sterile' Organs in Experimental Mice

Recent studies have shown that microorganisms can be present in organs or blood traditionally considered sterile, both in healthy and diseased individuals. In this study, we investigated the presence of microorganisms in the "sterile" organs (brain, heart, kidney, liver, lung, and spleen) of commercially available experimental mice using culturomics and metagenomics. To avoid potential environmental contamination, strict disinfection assays were performed. Among 104 mice of the C57BL/6J, BALB/c, and ICR strains purchased from three major experimental animal suppliers in China, 23 mice (22.1%) exhibited a high microbial burden (>1 x 104 CFU/g tissue) in at least one organ, and 42 mice (40.4%) exhibited >1 x 103 CFU/g tissue in at least one organ. In total, 216 microbial species were identified through culturomics. Of them, 56 microbial species were found in the organs of at least three mice of the 42 mice (>1 x 103 CFU/g tissue in at least one organ). Metagenomics analysis of 10 high-burden mice verified the existence of microbes in the mouse organs and identified 262 species. Several species, including Acinetobacter sp., Alcaligenes faecalis, and Ligilactobacillus murinus, were identified as the most abundant microbes across both culturomics and metagenomics assays. 16S FISH staining assays verify the presence of microbes in the mouse organs. Feces Metagenomics analysis and detection of the wide distribution of L. murinus in the mouse mesenteric lymph nodes (MLNs) imply that microbial cells could be translocated from the gut to the MLNs and then to the remote tissues. Together, these findings reveal the presence of non-pathogenic microorganisms in the "sterile" tissues of experimental mice, raising concerns about potential variability in experimental outcomes when using such animals in research.

microbiology↗

Functional Modulation of Retrotrapezoid Neurons Drives Fentanyl-Induced Respiratory Depression

The primary cause of death from opioid overdose is opioid-induced respiratory depression (OIRD), characterized by severe suppression of respiratory rate, destabilized breathing patterns, hypercapnia, and heightened risk of apnea. The retrotrapezoid nucleus (RTN), a critical chemosensitive brainstem region in the rostral ventrolateral medullary reticular formation contains Phox2b+/Neuromedin-B (Nmb) propriobulbar neurons. These neurons, stimulated by CO2/H+, regulate breathing to prevent respiratory acidosis. Since the RTN shows limited expression of opioid-receptors, we expected that opioid-induced hypoventilation should activate these neurons to restore ventilation and stabilize arterial blood gases. However, the ability of the RTN to stimulate ventilation during OIRD has never been tested. We used optogenetic and pharmacogenetic approaches, to activate and inhibit RTN Phox2B+/Nmb+ neurons before and after fentanyl administration. As expected, fentanyl (500 {micro}g/kg, ip) suppressed respiratory rate and destabilized breathing. Before fentanyl, optogenetic stimulation of Phox2b+/Nmb+ or chemogenetic inhibition of Nmb+ cells increased and decreased breathing activity, respectively. Surprisingly, optogenetic stimulation after fentanyl administration caused a significantly greater increase in breathing activity compared to pre-fentanyl levels. By contrast chemogenetic ablation of RTN Nmb neurons caused profound hypoventilation and breathing instability after fentanyl. The results suggest that fentanyl does not inhibit the ability of Phox2b+/Nmb+ cells within the RTN region to stimulate breathing. Thus, this study highlights the potential of stimulating RTN neurons as a therapeutic approach to restore respiratory function in cases of OIRD.

physiology↗

Optimized antibody with W32I mutation enhances antiviral efficacy against influenza

The influenza virus has caused a global pandemic with significant morbidity and mortality, highlighting the need to optimize antibodies for improved antiviral efficacy. The 3E1 antibody effectively neutralizes influenza subtypes H1 and H5 by inhibiting acid-induced conformational changes of hemagglutinin (HA). This study aimed to optimize the antibodys bioactivity by modifying amino acid residues, resulting in single-point mutants (3E1-L [W32I], 3E1-H [F103I]) and a double mutant (3E1-H+L [F103I, W32I]). The binding affinity, neutralizing activity, and antiviral mechanisms of the mutants were evaluated. Notably, the 3E1-L mutant showed significantly enhanced antiviral activity against H1N1 and H3N2 compared to wild-type 3E1, inhibiting both viral entry and release. The prophylactic and therapeutic efficacy of the 3E1-L mutant was validated. Molecular dynamics simulations of the 3E1-L/HA complex showed that the W32I mutation reduces steric hindrance between tryptophan at position 32 and the complementarity-determining region (CDR) L1 loop of HA. In conclusion, the W32I substitution enhances the antiviral activity of wild-type 3E1, making the optimization of 3E1-L a promising strategy for developing more effective influenza therapies.

immunology↗

Flaviviruses Hijack HuR to Suppress CNPY3: A Novel Pathway for Immune Evasion and Therapeutic Intervention

Flaviviruses represent a serious global health threat, infecting millions annually with high rates of cross-infection among different flaviviruses, yet no broad-spectrum antiviral therapy currently targets these pathogens. Through biological big data analysis, we observed a significant downregulation of Canopy FGF Signaling Regulator 3 (CNPY3), a positive regulator of defense responses, in flavivirus-infected patients, with the level of downregulation correlating with infection severity. This observation was validated in cellular and animal models. Mechanistically, we demonstrate that flaviviruses hijack the RNA-binding protein Human antigen R (HuR) to destabilize CNPY3 mRNA via adenine-uridine-rich elements (AREs), thus downregulating CNPY3 expression and promoting viral replication. Our findings identify CNPY3 as a novel antiviral mediator essential for the TLR-mediated type I interferon (IFN-I) pathway in defense against flaviviruses. In vitro, CNPY3 overexpression reduced DENV and ZIKV replication, confirming its antiviral role. To explore therapeutic potential, we developed lipid nanoparticles (LNPs) encapsulating CNPY3 mRNA (LNP-CNPY3), and early administration in flavivirus-infected mice improved survival, reduced viral loads, and attenuated neuroinflammation by enhancing antiviral and interferon responses. Together, these findings establish CNPY3 as a critical antiviral target and support LNP-CNPY3 as a promising therapeutic approach against flavivirus infections.

microbiology↗

Machine learning engineered PoLixNano nanoparticles overcome delivery barriers for nebulized mRNA therapeutics

There continues to be a dearth of competent inhalable mRNA delivery although it holds great potential for addressing a wide variety of refractory diseases. The huge advances seen with parenteral-administered lipid nanoparticle (LNP) have not been translated into nebulized mRNA delivery due to the aggressive nebulization process and insurmountable barriers inherent to respiratory mucosa. Here, we show amphiphilic block copolymers revealed by machine learning (ML) can spontaneously form stabilized nanoparticles (PoLixNano) with the lipids components of LNP and simultaneously impart the PoLixNano with "shield" (shear force-resistant) and "spear" (pulmonary barriers-penetrating abilities) capabilities. We present a ML approach that leverages physicochemical properties and inhaled mRNA transfection profiles of a chemically diverse library of polymeric components to validate the integration of "shield" and "spear" properties as highly predictive indicators of transfection efficiency. This quantitative structure-mRNA transfection prediction (QSMTP) model identifies top-performing amphiphilic-copolymers from more than 10000 candidates and suggests their mucus-penetrating ability outweights the shear force-resistant property in contributing to efficient mRNA transfection. The optimized PoLixNano substantially outperforms the LNP counterpart and mediates up to 1114-times higher levels of mRNA transfection in animal models with negligible toxicities. The PoLixNano promotes overwhelming SARS-CoV-2 antigen-specific sIgA antibody secretion and expansion of TRM cells which collectively confers 100% protection in mice against lethal SARS-CoV-2 challenges and blocks the transmission of Omicron variant between hamsters. PoLixNano also displays versatile therapeutic potential in lung carcinoma and cystic fibrosis models. Our study provides new insights for designing delivery platforms of aerosol-inhaled mRNA therapeutics with clinical translation potential.

synthetic biology↗

Prenatal stress increases corticosterone levels in offspring by impairing placental glucocorticoid barrier function

To investigate the association between prenatal stress (PS) and corticosterone, and its influence on DNA methylation of genes related to the placental glucocorticoid (GC) barrier, including 11{beta}-HSD2, P-gp, NR3C1, and FKBP5. The PS model was established through chronic unpredictable mild stress (CUMS). DNA methylation of GC-related genes was analyzed using reduced representation bisulfite sequencing (RRBS), and the results were confirmed using MethylTarget sequencing. The mRNA and protein expression levels of these genes were detected through qRT-PCR and Western blotting, respectively. Plasma corticosterone levels are elevated in pregnant female rats exposed to PS conditions and their offspring. Compared to the offspring of the prenatal control (OPC) group, the offspring of the prenatal stress (OPS) group showed down-regulation in both mRNA and protein expression of DNMT 3A and DNMT 3B, while up-regulation was observed in the expression of DNMT1. RRBS analyses identified P-gp and FKBP5 as hypermethylated genes, including a total of 43 differentially methylated sites (DMS) and 2 differentially methylated regions (DMR). MethylTarget sequencing revealed that both genes had 15 differentially methylated CpG sites. This study provides preliminary evidence that PS disrupts the placental GC barrier through abnormal gene expression caused by hypermethylation of GC-related genes, resulting in elevated corticosterone levels in offspring and affecting their growth and development.

developmental biology↗

Ancient inversion polymorphisms are locally adaptive in a widespread butterfly species

Wide-ranging species are subject to varying biotic and abiotic selection pressures across their distribution. While local adaptation does not manifest in obvious morphological changes, population genomic studies can reveal cryptic diversity and provide insights into local adaptive processes. In this study, we investigated the biogeographic history and genomic diversity across the range of the zebra longwing butterfly Heliconius charithonia, a species with a widespread distribution in the Neotropics, but which is phenotypically homogenous across its range. We examined whole genome sequence data from 55 individuals from the eight described subspecies. We infer that there were at least two distinct colonization events of the Caribbean islands from the mainland. The second colonization wave occurred relatively recently, accounting for the genetic homogeneity observed across the species range. Despite low divergence across most of the genome, two large non-recombining genomic regions showed deeply divergent haplotypes that correspond to chromosomal inversions. Phylogenetic analyses indicate ancient origins of these inversion polymorphisms, and there is no evidence that they were introgressed from another extant lineage of Heliconius. These ancient polymorphisms are likely maintained by heterogeneous selection across the landscape, with the inversion on chromosome 19 likely playing a role in local adaptation to cold and desiccation. Our findings underscore the importance of genomic analysis in uncovering hidden diversity and adaptation in phenotypically homogenous species and highlight the significant role of chromosomal inversions in driving local adaptation.

evolutionary biology↗

Airway applied IVT mRNA vaccine needs specific sequence design and high standard purification that removes devastating dsRNA contaminant

The development of next-generation mucosal mRNA vaccines is promising but extremely challenging. Major efforts have been focused on optimizing delivery systems, whereas it is still unknown whether the intrinsic quality of IVT mRNA significantly impacts the potency of airway inoculated mRNA vaccines. Here, we systematically demonstrate the mucosal mRNA vaccine requires a higher standard of purification and tailor-designed sequence to fulfil its potency compared to the parenteral route inoculated counterpart. We found double strand RNA (dsRNA) contaminants are prone to trigger innate immunoreaction in the airway that activates the mRNA degradation mechanism, thereby diminishing the mRNA expression and subsequent antigen-specific immune responses. To address these challenges, we developed a strategy that combines optimized untranslated regions (UTRs) screened from endogenous genes of pulmonary cells with affinity chromatography-based purification which removes almost all the dsRNA contaminants. The optimized mRNA administered via the airway route not only demonstrates superior protein expression (30-fold increase) and reduces inflammation in the lung, but also promotes robust immunity comprising significantly elevated systemic, cellular, and mucosal immune responses, which is in stark contrast to intramuscular injected counterpart that displays less pronounced benefits. Our findings offer new insight into the development of mucosal mRNA therapeutics from an overlooked but crucial perspective of optimizing mRNA components.

synthetic biology↗