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Biology subjects

Yan, W.

Publications and source records attributed to Yan, W..

At least 19 recordsLinked to original sources

Life without cytoplasm: sperm sustain protein production utilizing cytoplasmic droplets and mitochondria as translational apparatuses

Sperm present a unique paradox: heavily compacted chromatin silences transcription, and loss of cytoplasm during spermiation eliminates the conventional translational apparatus, yet sperm require [~]10 days of protein-demanding epididymal maturation to acquire motility and fertilization competence. How sperm produce the necessary proteins has remained enigmatic. Here, we show that mammalian sperm sustain protein synthesis through a biphasic translational program. In testicular sperm, a residual cytoplasmic droplet retains the full complement of translational machinery, including ribosomes and intact tRNAs, and supports nascent protein synthesis. As sperm enter the epididymis, this droplet is progressively fragmented, and protein synthesis shifts to the midpiece, where mitochondrial translation machinery becomes active. Proteomic and functional analyses indicate that both systems contribute to sperm maturation. Inhibiting cytoplasmic translation in testicular sperm or mitochondrial translation in epididymal sperm abolishes motility. These findings reveal how cytoplasm-free sperm overcome transcriptional silence to complete maturation and support male fertility. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=137 SRC="FIGDIR/small/744062v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@e4285forg.highwire.dtl.DTLVardef@11685d7org.highwire.dtl.DTLVardef@1ad1913org.highwire.dtl.DTLVardef@1495d6a_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

Paternal Metabolic Reversal Remodels Sperm RNA Profiles and Ameliorates Intergenerational Metabolic Disorder in Mice

Paternal obesity increases metabolic risk in offspring, but whether this risk can be reduced by restoring paternal health before conception remains unresolved. We developed a within-sire induction-and-reversal model in outbred CD1 mice in which high-fat diet (HFD)-exposed males generated offspring before and after transition to an ingredient-matched control diet with voluntary exercise. HFD caused obesity, glucose intolerance, insulin resistance, and extensive remodeling of sperm mRNA, lncRNA, and sncRNA profiles, together with transcriptomic changes in metabolic tissues. Diet and exercise reversal normalized paternal metabolic indices and broadly restored tissue RNA profiles, although sperm retained a limited transcriptional memory of prior HFD exposure. Offspring sired before reversal developed sex-dependent metabolic dysfunction despite control-diet rearing, whereas offspring sired after reversal showed substantial improvement. These findings show that paternal metabolic risk is modifiable before conception and that this reversibility is linked to remodeling of sperm RNA. (140 words) HighlightsO_LIPaternal HFD-Ex induces obesity, glucose intolerance and insulin resistance in CD1 males C_LIO_LISperm shows much stronger RNA response than four metabolic organs profiled C_LIO_LIDiet and exercise reversal restores metabolism and RNA profiles in sperm and four metabolic organs analyzed C_LIO_LIOffspring metabolic risk is reduced when sires conceive after reversal through diet and exercise intervention C_LI eTOC BlurbChen, Magalhaes, et al. show that paternal metabolic recovery before conception remodels sperm RNA and reduces transmission of HFD-associated metabolic risk to offspring in a within-sire mouse model.

genetics↗

A Comprehensive Computational Model of the Human head for Designing and Optimizing Visual Brain-Machine Interfaces

Brain-machine interfaces (BMIs) for vision restoration require models that accurately simulate the anatomy and electrical properties of visual pathways. However, current models focus only on isolated structures, such as the retina or brain, and overlook surrounding tissues. Here, we present a comprehensive computational model of the human head, incorporating the entire visual pathway--including the eye, optic nerve, and brain--along with critical neighboring tissues such as the orbit, paranasal sinuses, enabling precise simulations. Validation using human and large animal data demonstrated a strong correlation between the simulated and measured electrical potentials. Component elimination analysis revealed that the optimized comprehensive model outperformed simplified versions. The models utility was demonstrated through multiple applications: (1) comparative analysis of electrical neuromodulation technologies for optic neuropathy, revealing the filed intensity limitations of noninvasive approaches and the safety concerns of invasive intraorbital approach; (2) identification of optimal stimulation site, revealing that transnasal stimulation at the optic chiasm outperformed traditional approaches; and (3) in silico design of electrode arrays for optic nerve prosthetics, demonstrating theoretical advantages in invasiveness and visual field coverage compared to existing retinal and cortical prosthetics. This validated and versatile computational resource supports the development of neuromodulation strategies and visual BMI technologies.

bioengineering↗

SpacerScope: Binary-vectorized, genome-wide off-target profiling for RNA-guided nucleases without prior candidate-site bias

The precision of CRISPR/Cas systems is fundamental to their application in plant and animal biotechnology. However, comprehensive off-target assessment remains a bottleneck, particularly in large, complex genomes where existing tools often suffer from prohibitive computational costs, poor search-space convergence, and limited sensitivity toward non-canonical alignments involving insertions and deletions (indels). To address these limitations, we developed SpacerScope, an off-target analysis framework that enables unbiased, genome-wide discovery by leveraging binary vectorization and high-speed bitwise operations. Benchmarking against CIRCLE-seq data demonstrated that SpacerScope recovered 100% of validated off-target sites (6,142/6,142) within our defined parameter space, achieving zero false negatives while identifying additional high-risk sites with complex edit distances. Unlike conventional tools such as Cas-OFFinder, CHOPCHOP, and CRISPOR, SpacerScope maintains high sensitivity for indel-inclusive off-targets that are otherwise overlooked. Our results establish SpacerScope as a high-speed, high-sensitivity solution for ensuring genome-editing specificity across diverse and complex genomic landscapes. The full source code, documentation, and multi-platform executables are available at https://github.com/charlesqu666/SpacerScope. Graphical TOCSpacerScope is a genome-wide off-target profiling tool for RNA-guided nucleases that combines binary vectorization, bitwise prefiltering, compact 2-bit substitution search, and right-end-anchored indel validation. In the evaluated datasets, it recovered all 6,142 parameter-defined true off-target sites from CIRCLE-seq and showed improved detection of indel-containing candidate sites relative to the previous tools tested here. SpacerScope provides interpretable event-level annotations and empirical risk scores for downstream guide assessment. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/715005v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@bad2ddorg.highwire.dtl.DTLVardef@169b0aborg.highwire.dtl.DTLVardef@1cde3b2org.highwire.dtl.DTLVardef@1fbd11_HPS_FORMAT_FIGEXP M_FIG C_FIG Practitioner Points> SpacerScope enables genome-wide off-target profiling with explicit support for substitutions, insertions, and deletions in a single workflow. > The method combines binary-channel prefiltering with right-end-anchored validation to reduce the search space while preserving sensitivity within the evaluated parameter ranges. > SpacerScope returns event-level match annotations and empirical risk scores, supporting more interpretable downstream guide selection and benchmarking.

bioinformatics↗

Construction of a GnRH mRNA Immunocastration Vaccine and Evaluation of Its Immunogenicity and Safety in Mice and Cats

Immunocastration has emerged as an alternative to surgical and chemical castration for managing reproductive function in animals, yet the development of safe and effective vaccines remains challenging. This study aimed to develop a gonadotropin-releasing hormone (GnRH)-based messenger RNA (mRNA) vaccine and systematically evaluate its immunogenicity, reproductive suppression efficacy, long-term durability, and biosafety in mice and cats. GnRH epitopes were fused to three carrier proteins, Fc, Foldon, and lumazine synthase nanoparticles (pLS) via a flexible linker. After identifying pLS as the optimal scaffold, three mRNA vaccine candidates (GnRH-3, GnRH-4, and GnRH-5) were generated with one, five, or ten tandem GnRH repeats, encapsulated in lipid nanoparticles (LNPs), and assessed in rodent and feline models. Immunogenicity was determined by enzyme-linked immunosorbent assay, gonadal histopathology, hormone measurements, transcriptomic analysis, and mating trials. Among the fusion partners, the pLS-based vaccine (GnRH-3) induced the strongest antibody responses and most pronounced reproductive suppression. Further optimization showed that GnRH-4, containing five tandem GnRH repeats, elicited the highest antibody titers, induced severe gonadal atrophy, and reduced litter size by 93.8% in mice. Transcriptomic analysis revealed that differentially expressed genes in males were enriched in spermatogenesis and motility pathways, whereas those in females were associated with RNA splicing and immune responses. In cats, the optimal regimen was a twoLdose schedule with 50Lg per dose and a 21Lday interval, which induced robust antibody responses lasting at least 12 Lmonths and sustained reproductive suppression. HighLdose (500Lg) administration showed no clinical toxicity or histopathological abnormalities, confirming favorable biosafety. This study successfully developed a pLSLbased GnRH mRNA vaccine (GnRH-4) with five tandem GnRH epitopes that demonstrates strong immunogenicity, longLlasting contraceptive effects, and excellent safety in both rodent and feline models, supporting its potential for clinical application in immunocastration.

immunology↗

Cell jamming transition is regulated by mitochondrial pyruvate transport and endocytosis

Epithelial tissues undergo dynamic transitions between fluid-like collective motion and mechanically jammed states during development, injury repair, and disease progression. However, the cellular programs that drive these transitions and regulate collective behavior remain unclear. Using a controlled crowding model integrated with live-cell imaging and time-resolved multi-omics, we demonstrate that epithelial crowding triggers early metabolic changes characterized by increased mitochondrial pyruvate anaplerosis that precedes the jamming transition. Functional inhibition of mitochondrial pyruvate import is sufficient to sustain collective cell motility, impeding jamming transition in crowded cells. This unjammed state is driven by enhanced cytoskeletal remodeling and requires RhoA-myosin II activity. Mechanistically, we show that elevated cytoskeletal signaling promotes macropinocytic uptake, which serves as a required feedback loop to maintain motility. These findings identify mitochondrial pyruvate utilization as a key regulator that links metabolic remodeling to the endocytic control of epithelial fluidity.

cell biology↗

Nab-paclitaxel fused with the de novo designed receptor binder exhibits enhanced tumor targeting and therapeutic efficacy

Chemotherapy has been widely used in cancer treatment, but most of the chemotherapeutic drugs rely mainly on passive accumulation due to lack of target specificity, which may lead to systemic toxicity and limited clinical utility. Recent advances in artificial intelligence-based protein design provide new opportunities for developing precision therapeutics. Here we modify the albumin-bound paclitaxel (Nab-PTX), one of the most widely used drugs in chemotherapies, by applying the fusion proteins of albumin with the de novo designed protein binders targeting human EGFR or HER2. The resulting particles, EGFRmb-Nab-PTX and HER2mb-Nab-PTX, retain the similar physicochemical properties of Nab-PTX while acquiring the receptor-specific binding capacities. The in vitro assays show that both binder-modified Nab-PTX particles have increased uptake and inhibitory effects significantly in the cancer cell lines with high receptor expression levels. Furthermore, the data from a xenograft model, including tumor growth, excised tumor analysis, organ histology, and fluorescence imaging, show that the binder-modified Nab-PTX enhances tumor accumulation, improves tumor suppression, and reduces off-target toxicity compared with the conventional Nab-PTX, suggesting that they may have promising clinical potential in cancer treatment. Overall, this strategy provides an adaptable modular platform for generating albumin-based chemotherapeutic drugs with target specificities, which can be readily customized with diverse target binders to enable precise cancer therapies.

cancer biology↗

Mechanistic Language Modeling and Oxygenated 3D Screening Reveal Berberine and Enzalutamide Synergy in Resistant Prostate Cancer

Resistance to androgen receptor inhibitors remains a primary challenge in prostate cancer treatment, yet identifying synergis-tic co-therapies is hindered by immense combinatorial search spaces and the limited interpretability of predictive computation models. Here, we developed an integrated discovery-validation axis coupling knowledge-augmented large language models with oxygen-supplemented 3D spheroid assays. By leveraging inherent model stochasticity, our framework measures the degree of consensus across independent predictions to establish a formal metric for predictive accuracy. This principle enables high-throughput assessment of complex signaling crosstalk, yielding mechanistic rationales for all predictions and defining a high-confidence zone that minimizes experimental attrition. Utilizing this approach to screen 3,592 natural products, we identified a previously unrecognized synergy between berberine and enzalutamide that re-sensitizes resistant cells. Validation confirms that berberine perturbs the PI3K/AKT/mTOR and AMPK axes, a finding consistent with the mechanistic rationales computationally derived by the framework. Integrating interpretable AI with physiologically relevant 3D screening provides a scalable methodology for the rational discovery of synergistic therapies. SignificanceIntegrating mechanistic AI with oxygenated 3D screening, we identify a novel berberine-enzalutamide synergy. This framework resolves complex signaling dependencies, providing a scalable, transparent methodology for the rational discovery of effective combination therapies.

bioengineering↗

Aspartate Transaminases Are Dispensable for Pancreatic Development and Pancreatic Cancer Progression

Pancreatic ductal adenocarcinoma (PDA) is the third leading cause of cancer-related deaths in the United States. This is due in part to the limited availability of effective treatment options for patients, highlighting a significant need for new targets and approaches. Deregulated metabolism is a hallmark feature of PDA that has gained attention as a promising inroad for therapy. The aspartate transaminases (glutamate oxaloacetate transaminases, cytosolic GOT1 and mitochondrial GOT2) have several important metabolic functions, including maintaining energy and redox balance and generating aspartate, an essential building block in protein and nucleotide biosynthesis. Previous studies of GOT proteins in preclinical tumor transplant models have yielded conflicting results regarding the requirement of GOT1 and GOT2 for PDA tumor growth. To assess the role of GOT proteins in tumor development and tumor maintenance, we generated conditional knockout mice for Got1 and Got2 and crossed these into pancreas-specific models. Whereas loss of either Got does not impact pancreas development, double Got1 and Got2 knockout results in markedly reduced pancreas size and cellularity without overtly impacting endocrine or exocrine function. In genetically engineered cancer models, single Got loss does not impact lesion formation, tumor size, animal survival, or the composition of the tumor microenvironment. Identical results were also observed in orthotopic allograft mouse models. Together, these findings add to a growing body of work illustrating the adaptability of metabolism in cancer. They also emphasize the importance of model selection, the use of multiple independent models, and the in vivo context when studying the role of metabolic programs in cancer.

cancer biology↗

Genome-wide CRISPR screen reveals PEX11B as a host restriction factor against ORFV through membrane fluidity regulation

Host-pathogen interactions are shaped by cellular restriction factors that direct antiviral defenses. We built the first ovine genome-wide CRISPR knockout library in sheep testis (OA3.Ts) cells, targeting all protein-coding genes. Using this platform, we identified PEX11B, a peroxisomal membrane regulatory protein, as a strong restriction factor against orf virus (ORFV) infection. Removing PEX11B increased viral susceptibility and triggered severe cytopathic effects with membrane fusion and syncytia formation. Mechanistic studies showed that PEX11B knockout harmed peroxisomal integrity and disrupted lipid metabolism. This led to greater plasma membrane fluidity, creating a proviral environment that allowed more viral entry and replication. These results reveal a new antiviral function for PEX11B in blocking viral infection and underscore the importance of peroxisomal regulation in host-virus interactions.

microbiology↗

Large mRNA language foundation modeling with NUWA for unified sequence perception and generation

The mRNA serves as a crucial bridge between DNA and proteins. Compared to DNA, mRNA sequences are much more concise and information-dense, which makes mRNA an ideal language through which to explore various biological principles. In this study, we present NUWA, a large mRNA language foundation model leveraging a BERT-like architecture, trained with curriculum masked language modeling and supervised contrastive loss for unified mRNA sequence perception and generation. For pretraining, we utilized large-scale mRNA coding sequences comprising approximately 80 million sequences from 19,676 bacterial species, 33 million from 4,688 eukaryotic species, and 2.1 million from 702 archaeal species, and pre-trained three domain-specific models respectively. This enables NUWA to learn coding sequence patterns across the entire tree of life. The fine-tuned NUWA demonstrates strong performance across a variety of downstream tasks, excelling not only in RNA-related perception tasks but also exhibiting robust capability in cross-modal protein-related tasks. On the generation front, NUWA pioneers an entropy-guided strategy that enables BERT-like models in generating mRNA sequences, producing natural-like sequences that accurately recapitulate species-specific codon usage patterns. Moreover, NUWA can be effectively fine-tuned on small, task-specific datasets to generate functional mRNAs with desired properties, including sequences that do not exist in nature, and to design coding sequences for diverse proteins in biomanufacturing, vaccine development, and therapeutic applications. To our knowledge, NUWA represents the first mRNA language model for unified sequence perception and generation, providing a versatile and programmable platform for mRNA design.

bioinformatics↗

Universal super-resolution for subcellular fluorescence imaging

Super-resolution fluorescence microscopy has emerged as an essential instrument for investigating subcellular structures and monitoring intracellular physiology. Despite rapid advances driven by deep learning, most existing approaches are modality specific and exhibit limited generalizability, restricting their practical applicability. Here we introduce universal super-resolution (UniSR), a framework that operates across microscopes and subcellular structures without optical modifications or prior sample knowledge. UniSR is initially pre-trained on simulated image pairs to establish mappings from low-to high-resolution features and subsequently fine-tuned with only one experimental image pair, reducing data demand and acquisition time. Across wide-field and point-scanning modalities, UniSR enhances resolution to match structured illumination, single-molecule localization, or stimulated emission depletion microscopy. Applied to diverse biological samples, it reveals nanoscale structures, dynamic processes, and organelle interactions with high spatiotemporal fidelity. UniSR provides a practical and broadly generalizable tool for super-resolution imaging in live-cell research.

bioinformatics↗

Sulcal landmarks reveal lineage-specific trajectories and multi-scale specialization of the mammalian cortex

An important topic of evolutionary neuroscience is to understand how brain function and structure across evolutionary time. In the absence of functional data for ancestral species, studies often rely on structural features such as cortical volume or surface area. However, atlas-based metrics derived from human or a few model organisms lack biological interpretability across species with divergent cortical architectures. Here, we investigate sulcal pits--the locally deepest points of cortical folds--as conserved, atlas-independent landmarks that provide a robust basis for cross-species comparison. Using cortical surface reconstructions from 90 mammalian species, we show that sulcal pit distribution patterns partly recapitulate phylogenetic relationships, independent of overall brain size (volume and surface area), and vary systematically with ecology and lifestyle. By tracing pit-based evolutionary trajectories from 80 million years ago to the present, we found pronounced differences across ecological and behavioral categories, indicating that cortical folding has diversified in close association with species habitats, lifestyles, and social structures. Using sulcal pits, we identified Homo sapiens-specific regions and species-shared regions. The Homo-specific areas were functionally associated with higher cognitive and emotional processes, distinguished by unique histological features, enriched for gene sets related to neural regulation, and exhibited markedly different cell-type abundance profiles compared to shared regions. Together, these results establish sulcal pits as a robust, evolutionarily informative feature for cross-species cortical alignment, offering new insights into the structural innovations underlying brain evolution study.

evolutionary biology↗

Evaluation of a Polarization-Sensitive, Dual-Wavelength Wearable Photoplethysmography Sensor Across a Range of Skin Tones

SignificanceHigh-quality photoplethysmography (PPG) signals are essential for accurate extraction of cardiovascular metrics such as heart rate, heart rate variability, and perfusion index. However, signal degradation for individuals with dark skin tones can compromise PPG quality and pose challenges for equitable sensing. AimWe develop a dual-wavelength, polarization-sensitive PPG device to assess perfusion index (PI) across a range of skin tones. ApproachTo evaluate the impact of polarization on PPG signal quality, we record PI for co-polarized (polarized illumination and parallel-aligned polarized detection), and cross-polarized conditions (polarized illumination and orthogonally aligned polarized detection) at 655 nm and 940 nm in participants representing light, medium, and brown skin tone categories. Skin tone classification are based on the individual typology angle (ITA) values derived from the CIE L*b* color space measurements. ResultsAt 940 nm, light from the cross-polarized light channel significantly increases PI (p < 0.05). At 655 nm, cross-polarization presents a statistically significantly enhanced PI (p < 0.05) relative to light from the co-polarized illumination condition, although the magnitude of the improvement decreases with lighter skin tone indication a possible interaction between skin tone and polarization. This improvement is consistent across all skin tones. ConclusionsOur results suggest that the cross-polarized condition improves PPG signal quality by reducing the influence of superficial scattering and enhancing deeper vascular signals. This approach may be especially beneficial for individuals with darker skin tones and offers a promising path towards more robust and inclusive physiological monitoring using PPG-based technologies.

bioengineering↗

Unveiling The Origin of Human High-Grade Serous Ovarian Cancer Using Bulk and Single-Nucleus RNA Sequencing

High-grade serous ovarian cancer (HGSOC) is the most lethal gynecologic malignancy, yet its earliest cellular precursors remain incompletely defined. Here, we integrate bulk and single-nucleus RNA sequencing of human fallopian tubes, ovaries, and primary HGSOC tumors to resolve the epithelial hierarchy of the fallopian tube and examine its relationship to malignant states. We identify a rare LGR5/PGR basal population as putative epithelial stem cells and delineate a large pool of OVGP1/RNPC3 progenitors that give rise to both secretory and ciliated lineages. By jointly analyzing normal and malignant transcriptomes, we find that these progenitor populations show the strongest transcriptional and developmental continuity with multiple HGSOC cell states, suggesting that they represent the epithelial compartments most plausibly poised for oncogenic divergence. Transcription factor network reconstruction highlights SPDEF as a key regulator of progenitor identity and NR2F6 as a candidate oncogenic driver, while inferred copy number variations and microenvironmental collagen-integrin signaling further illuminate the genomic and stromal factors that consolidate malignant fate. Together, these findings refine the cellular landscape of the human fallopian tube and identify progenitor-enriched molecular features that could inform earlier detection, improved risk stratification, and new preventive strategies for women at risk of developing HGSOC. One sentence summaryFallopian tube progenitor cells represent a key intermediate state linking normal epithelial hierarchy to the earliest stages of high-grade serous ovarian cancer development.

cancer biology↗

JointMap identified SERPINA3+ chondrocytes as a therapeutic target for osteoarthritis

BackgroundOsteoarthritis (OA) is a prevalent degenerative joint disease that affects nearly half of the population aged over 65. Recent single-cell transcriptional studies have identified heterogeneous OA-specific chondrocyte subtypes, yet a unified subtype-classification remains incomplete. MethodsIn this study, we integrated a total of 545,946 cells to develop JointMap, an interspecies atlas. The chondrocyte subtypes were analyzed using machine learning algorithms were validated via human samples, animal models, and in vitro cell culture. We performed KAS-seq and analyzed the spatial characters for JointMap. ResultsBased on clinical diagnosis and cross-omic indexes, we identified a novel OA-elevated chondrocyte subtype, SERPINA3+ chondrocytes. Notably, we uncovered their upregulated chondrogenesis function and intercellular communication patterns as potential therapeutic targets. ConclusionsIn summary, JointMap provides a unified framework for the systematic annotation of chondral tissues across species and helps in the identification of druggable networks for articular diseases.

bioinformatics↗

An Objective Detection Method for Tinnitus using Memristors

Approximately 10-20% of the world population experiences tinnitus, which is increased with age and comorbid with frustration, annoyance, anxiety, depression, cognitive dysfunction, insomnia and stress. The underlying mechanisms of tinnitus remain largely unknown and there are no quantifiable biomarkers, making this prevalent disorder a global burden. There are no FDA-approved therapeutics and the current assessment mainly relies on self-reports (e.g., questionnaires), which underscore the need for diagnostic tools for tinnitus. Memristors, nanoscale electronic components mimicking synaptic plasticity, can monitor and control neuronal activity, hold transformative potential for detecting and characterizing tinnitus objectively. Here, we harvested the blood from human and mice with tinnitus, and engineered memristors via magnetron sputtering and made the functional layer with serum. Its core mechanism lies in regulating the reversible formation and rupture of conductive filaments which is formed by utilizing abnormally elevated glutamate concentrations in serum assisted Ag+ ions. This serum-based memristor achieves unprecedented discrimination between tinnitus and non-tinnitus individuals. Furthermore, this platform provides mechanistic insights into tinnitus pathogenesis, with potential implications in other neurological disorders.

pathology↗

Subtype-specific neutralizing antibodies promote antigenic shift during influenza virus co-infection

Reassortment between different influenza strains occurs when they co-infect the same host cell. The emergence of a reassortant virus depends on both its intrinsic fitness and extrinsic factors, including pre-existing humoral immunity. The generation of pandemic strains, such as H2N2 and H3N2, and zoonotic influenza A viruses, like H5N6, H5N8, and H7N9, in birds is suggested to be the result of extensive selection by pre-existing antibodies. To further explore the role of humoral immunity in reassortment, we generated two divergent fluorescent protein-expressing viruses and used strain-specific and cross-reactive monoclonal antibodies (mAbs) to assess the impact of cross-immunity on reassortment. Our results indicate that all mAbs altered the genotypic diversity and significantly reduced the release of progeny virions in co-infected cells both in vitro and in vivo. Moreover, antibody transfer studies in mice revealed protection from challenge with divergent pathogenicity profiles. Notably, selection driven by a strain-specific mAb depended on its neutralizing specificity, whereas the selection driven by broadly reactive mAbs was independent of neutralization specificity. Our findings demonstrate that pre-existing neutralizing antibodies shape reassortment and that strain-specific neutralizing antibodies promote antigenic shift during co-infection, which is not the case for broadly cross-reactive antibodies that recognize influenza viruses from different subtypes.

microbiology↗