Biology subjects

Hur, J.

Publications and source records attributed to Hur, J..

At least 19 recordsLinked to original sources

bioRxiv2026

TFAM Dependent Mitochondrial Fitness Limits CD8⁺ T Cell Immunopathology and Sustains Protective Immunity during Viral Pneumonia

During respiratory virus infection, CD8 T cells kill infected cells and establish antigen-specific memory, but mechanisms regulating these functions remain incompletely understood. Here, we identify mitochondrial transcription factor A (TFAM)-dependent mitochondrial fitness as a regulator of CD8 T cell function during influenza infection. Human CD8 T cells exhibited an age-associated decline in TFAM expression and mitochondrial function. To model this physiologically relevant decline and determine its consequences for antiviral immunity, we generated CD8 T cell-specific TFAM-haploinsufficient mice. TFAM insufficiency disrupted mitochondrial integrity and bioenergetics and increased mitochondrial DNA and oxidative stress. During influenza infection, TFAM-insufficient CD8 T cells exhibited increased cytotoxic and inflammatory activity associated with lung immunopathology without improved viral control. This early phenotype was followed by loss of effector function, diminished antigen-specific responses, reduced protection following adoptive transfer, and impaired heterosubtypic recall immunity. Thus, TFAM-dependent mitochondrial fitness is a cell-intrinsic regulator that limits immunopathology while sustaining recall immunity.

immunology↗

bioRxiv2026

Schema-Grounded Multitask Instruction Fine-tuning for Joint Biomedical Named Entity Recognition and Relation Extraction in Pharmacovigilance

MotivationPharmacovigilance relies on accurate extraction of structured biomedical entities and their semantic relationships from scientific literature. However, most biomedical information extraction systems address named entity recognition (NER) and relation extraction as separate tasks trained on corpus-specific architectures, limiting scalability and cross-task knowledge sharing. Recent developments in instruction-tuned Large Language Models (LLMs) offer a promising alternative through unified generative extraction, but robust schema-grounded multitask adaptation for biomedical extraction is still understudied. MethodsThis study proposes a unified multitask instruction-tuned LLM framework that jointly performs biomedical NER and relation extraction across three benchmark corpora to identify chemical, disease, drug entities, as well as chemical-disease relations, drug-adverse event relations, and drug-drug interactions. Two general LLMs, Llama-3.2-3B-Instruct and Qwen3-8B, were fine-tuned using Low-Rank Adaptation (LoRA) under a shared generation interface that extracts both entity pairs and their underlying relation. Zero-shot and fine-tuned configurations were evaluated across all the tasks on their respective held-out test sets. ResultsParameter-efficient fine-tuning substantially improved both entity and relation extraction performance across all tasks and model families. Fine-tuned Qwen3-8B achieved the strongest overall performance with 89.42% micro-averaged entity F1 and 62.32% micro-averaged relation F1. Fine-tuned Llama-3.2-3B achieved 87.63% entity F1 and 58.42% relation F1 despite its substantially smaller parameter count, outperforming the zero-shot 8B model on both tasks. Fine-tuning also reduced structured JSON parse failures from 23.5% to 0.11%, demonstrating stable schema internalization during supervised adaptation. ConclusionSchema-grounded multitask instruction tuning with LoRA provides a robust and computationally feasible framework for unified biomedical information extraction across heterogeneous benchmark corpora. The findings further demonstrate that schema-grounded adaptation is substantially more important than model scale alone for reliable extraction of structured biomedical relations. The gap between NER and relation extraction performance motivates future research on explicit negative-relation supervision and ontology-guided relation extraction.

pharmacology and toxicology↗

bioRxiv2026

Ignet 2.0 and Vignet: An Ontology-Driven Web Platform for Biomedical Gene Interaction Discovery and Visualization

BackgroundThe expansion of biomedical literature demands systematic ontology-guided discovery of gene interactions, vaccine mechanisms, drug associations, and adverse events. Existing platforms such as STRING, DisGeNET, and PubTator fall short of providing a unified, freely accessible system that integrates ontology-based semantic interaction classification, vaccine-focused heterogeneous network construction, and Artificial Intelligence-assisted evidence retrieval. ResultsIgnet 2.0 and Vignet are freely accessible dual-platform systems that combine PubMed literature mining, BioBERT-based interaction scoring for millions of gene-gene co-occurrence pairs and integrate three biomedical ontologies and one curated drug resource, Interaction Network Ontology (INO), Vaccine Ontology (VO), Human Disease Ontology (HDO), and DrugBank. Ignet 2.0 supports gene interaction discovery, gene set enrichment retrieval of BioBERT-scored GenePair evidence, and AI-assisted summarization through BioSummarAI. Vignet extends these features with VO-guided Vaccine Exploration, VacPair interaction scoring, and the creation of vaccine, gene, drug, and disease networks in VacNet. A public Representational State Transfer Application Programming Interface (REST API) and Model Context Protocol (MCP) endpoint enable real-time integration, fostering trust in biomedical knowledge discovery. ConclusionIgnet 2.0 and Vignet are scalable, ontology-guided biomedical knowledge platforms that facilitate evidence-based gene interaction analysis, vaccine-focused semantic exploration, and AI-assisted knowledge discovery. Their real-time PubMed data integration ensures up-to-date insights; however, users should consider validation processes and potential lags in incorporating the latest experimental data, which may affect the reliability of immediate data. AvailabilityIgnet 2.0: https://ignet.org/ignet; Vignet: https://ignet.org/vignet/

bioinformatics↗

bioRxiv2026

Rapid in vitro synthesis of DNA templates via Sidewinder for polyadenylated Hantavirus mRNA vaccine candidates

As the recent COVID-19 pandemic illustrated, zoonotic viruses and other pathogens pose a credible threat to public health. Recent advancements in vaccine technology, particularly mRNA vaccines, provide key tools for an effective and swift public health response. Although mRNA vaccines can be developed more quickly than traditional vaccines, fast and accurate construction of DNA templates for these vaccines remains a critical bottleneck. Using our novel DNA assembly technology, Sidewinder, we rapidly designed and built multiple mRNA vaccine candidates to guard against a potential outbreak of Hantavirus (ANDV). We successfully constructed the DNA templates from oligo pools and produced the mRNA for three vaccine candidates in just 2 days after delivery of the synthetic DNA oligos.

biochemistry↗

bioRxiv2026

Microfluidic Mechanical Reactivation of Aged Stem Cells

Stem cell aging significantly impairs therapeutic efficacy, requiring innovative strategies to restore potency. We present a microfluidic cell-compressing platform for reactivation (-CPR) designed to apply controlled hydrodynamic deformation to late-passage stem cells. This mechanical stimulation facilitates functional reactivation without external chemical cues. Within a defined window, -CPR effectively reduces oxidative stress, SA-{beta}-Gal activity, and {gamma}H2AX foci, while simultaneously restoring proliferation and canonical stemness markers (OCT4, SOX2, and KLF4). Mechanical stimulation via -CPR induces coordinated structural remodeling: nuclei become more compact, actin cortex organization is restored, -actinin redistributes to focal adhesions, and microtubule networks are restructured, suggesting a rebalanced intracellular tension. Transcriptomic and proteomic analyses reveal that this process reprograms extracellular matrix remodeling and DNA repair pathways while attenuating pro-fibrotic and senescence-associated secretory phenotype (SASP)-associated pathways. Crucially, this reactivation occurs without compromising fundamental MSC hallmarks, preserving intrinsic immunophenotypes and multilineage differentiation potential. Functionally, -CPR-processed stem cells demonstrate restored in vitro wound closure and enhanced tissue repair in vivo, with efficacy appearing dependent on mechanical dosage. This platform establishes a non-genetic, mechanobiological approach to restoring stem cell function, offering a scalable strategy for functional reactivation and potentially paving the way toward comprehensive cellular rejuvenation.

bioengineering↗

bioRxiv2025

NF-κB driven inflammation mediates loss of upper airway epithelial tolerance to Streptococcus pneumoniae during influenza co-infection

Streptococcus pneumoniae asymptomatically colonizes the human nasopharynx, where epithelial tolerance maintains mucosal homeostasis. However, influenza A virus (IAV) co-infection transforms this tolerogenic state into an inflammatory environment that promotes bacterial outgrowth and invasion. Here, we identify a TGF-{beta}1 dependent epithelial program that sustains mucosal tolerance during Spn colonization and demonstrate that IAV co-infection disrupts this pathway through IL-17RA-NF-{kappa}B driven inflammation in the nasopharynx. In a murine colonization model, TGF-{beta}1 blockade enhanced pro-inflammatory cytokine production and neutrophil recruitment, resulting in inflammation-driven Spn clearance. IAV co-infection suppressed epithelial TGF-{beta}1 signaling, increased TRAF6/NF-{kappa}B activation, and impaired tight junction integrity, leading to Spn dissemination. Mechanistically, IL-17RA signaling contributed to the hyperactivation of the TRAF6/NF-{kappa}B axis. Pharmacologic inhibition of TRAF6 or NF-{kappa}B restored epithelial barrier function and reduced Spn translocation in a human air-liquid interface nasopharyngeal epithelial model. These findings reveal a conserved epithelial signaling axis through which influenza disrupts mucosal tolerance and promotes Spn invasion, highlighting the canonical TRAF6-NF-{kappa}B pathway as a potential therapeutic target to preserve epithelial integrity and mitigate Spn infection during viral-bacterial co-infection of the upper respiratory tract.

immunology↗

bioRxiv2025

Fear, anxiety, and the extended amygdala- Absence of evidence for strict functional segregation

Since the time of Freud, the distinction between fear and anxiety has been a hallmark of influential models of emotion and emotional illness, including the Diagnostic and Statistical Manual of Mental Disorders (DSM) and Research Domain Criteria (RDoC). Fear and anxiety disorders are common, debilitating, and challenging to treat, underscoring the importance of developing accurate models of the underlying neurobiology. Although there is consensus that the extended amygdala (EA) plays a central role in orchestrating responses to threat, the respective contributions of its two major subdivisions--the central nucleus of the amygdala (Ce) and bed nucleus of the stria terminalis (BST)--remain contentious. To help adjudicate this debate, we performed a harmonized mega-analysis of fMRI data acquired from 295 adults as they completed a well-established threat-anticipation paradigm. Contrary to popular double-dissociation models, results demonstrated that the Ce responds to temporally uncertain threat and the BST responds to certain threat. In direct comparisons, the two regions showed statistically indistinguishable responses, with strong Bayesian evidence of regional equivalence. In contrast, frontocortical regions responded preferentially to uncertain-threat anticipation. Together, these observations underscore the need to reformulate conceptual models that posit a strict segregation of temporally certain and uncertain threat processing in the EA.

neuroscience↗

bioRxiv2025

SEA CDM: Study-Experiment-Assay Common Data Model and Databases for Cross-Domain Data Integration and Analysis

With the increasing volume of biomedical experimental data, standardizing, sharing, and integrating heterogeneous experimental data across domains has become a major challenge. To address this challenge, we have developed an ontology-supported Study-Experiment-Assay (SEA) common data model (CDM), which includes 10 core and 3 auxiliary classes based on object-oriented modeling. SEA CDM uses interoperable ontologies for data standardization and knowledge inference. Building on the SEA CDM, we developed the Ontology-based SEA Network (OSEAN) relational database and knowledge graph, along with a set of ETL (Extract, Transform, Load) and query tools, and further applied them to represent 1,278 immune studies with over two million samples from three resources: VIGET, ImmPort, and CELLxGENE. Using simple, robust queries and analyses, our research identified multiple scientific insights into sex-specific immune responses, such as neutrophil degranulation and TNF binding to physiological receptors, following live attenuated and trivalent inactivated influenza vaccination. The novel SEA CDM system lays a foundation for establishing an integrative biodata ecosystem across biological and biomedical domains.

bioinformatics↗

bioRxiv2025

Heightened subcortical reactivity to uncertain-threat is associated with future internalizing symptoms, conditional on stress exposure

BackgroundAnxiety, depression, and related internalizing illnesses are a leading burden on global public health, and often emerge during times of stress. Yet the underlying neurobiology has remained enigmatic, hindering treatment development. MethodsHere we used a combination of tools--including a well-established threat-anticipation fMRI paradigm and longitudinal assessments of internalizing symptoms and negative life events (NLEs)--to identify the neural systems associated with future internalizing illness in a risk-enriched sample of 224 emerging adults followed for 2.5 years. We performed parallel analyses in an overlapping sample of 209 participants who completed a popular threat-related faces paradigm. ResultsHere we show that heightened reactivity to uncertain-threat anticipation in the bed nucleus of the stria terminalis and the periaqueductal gray is associated with a worsening longitudinal course of broadband internalizing symptoms among individuals with low levels of NLE exposure. These associations were specific to uncertain threat and generally remained significant when controlling for concurrent measures of threat-elicited distress or psychophysiological arousal, highlighting the added value of the neuroimaging measures. Symptom trajectories were unrelated to amygdala and frontocortical reactivity to anticipated threat. Contrary to past research, amygdala reactivity to threat-related faces was unrelated to future symptoms. ConclusionsThese observations provide a novel neurobiological framework for conceptualizing transdiagnostic internalizing risk and lay the groundwork for mechanistic and therapeutics research. A racially diverse, risk-enriched sample and pre-registered, best-practices approach enhance confidence in the robustness and translational relevance of these results.

neuroscience↗

bioRxiv2025

Ontology-based Protein-Protein Interaction Explanation Using Large Language Models

Protein-protein interactions (PPIs) play a crucial role in various biological processes, and understanding these interactions is essential for advancing biomedical research. Automated extraction and analysis of PPI information from the rapidly growing scientific literature remains an important challenge. We present a novel ontology-based approach to analyze protein-protein interactions using Large Language Models (LLMs). We applied different learning strategies, namely in-context learning and parameter-efficient instruction fine-tuning for the Llama-2 chat models, to identify keywords in the text that indicate an interaction between a pair of proteins. Our results show that parameter-efficient fine-tuning leads to a performance gain even when the domain is new. The smaller fine-tuned models outperformed the zero-shot performance of much larger models. The keywords identified by the Llama-2 models were mapped to the ontology terms in the Interaction Network Ontology (INO). Our study suggests that a pipeline of an LLM and an ontology is an effective strategy for explaining relations between biomedical entities. This work demonstrates the potential of leveraging ontologies and advanced language models to advance automated PPI analysis from the scientific literature.

bioinformatics↗

bioRxiv2024

A shared threat-anticipation circuit is dynamically engaged at different moments by certain and uncertain threat

Temporal dynamics play a central role in models of emotion: "fear" is widely conceptualized as a phasic response to certain-and-imminent danger, whereas "anxiety" is a sustained response to uncertain-or-distal harm. Yet the underlying neurobiology remains contentious. Leveraging a translationally relevant fMRI paradigm and theory-driven modeling approach in 220 adult humans, we demonstrate that certain- and uncertain-threat anticipation recruit a shared circuit that encompasses the central extended amygdala (EAc), periaqueductal gray, midcingulate, and anterior insula. This circuit exhibits persistently elevated activation when threat is uncertain and distal, and transient bursts of activation just before certain encounters with threat. Although there is agreement that the EAc plays a critical role in orchestrating responses to threat, confusion persists about the respective contributions of its major subdivisions, the bed nucleus of the stria terminalis (BST) and central nucleus of the amygdala (Ce). Here we used anatomical regions-of-interest to demonstrate that the BST and Ce exhibit statistically indistinguishable threat dynamics. Both regions exhibited activation dynamics that run counter to popular models, with the Ce showing sustained responses to uncertain-and-distal threat and the BST showing phasic responses to certain-and-imminent threat. For many scientists, feelings are the hallmark of fear and anxiety. Here we used an independently validated multivoxel brain signature to covertly probe the moment-by-moment dynamics of anticipatory distress for the first time. Results mirrored the dynamics of neural activation. These observations provide fresh insights into the neurobiology of threat-elicited emotions and set the stage for more ambitious clinical and mechanistic research. SIGNIFICANCE STATEMENT"Fear" is widely viewed as a phasic response to certain-and-imminent danger, whereas "anxiety" is a sustained response to uncertain-or-distal harm. Prior work has begun to reveal the neural systems recruited by certain and uncertain anticipated threats, but has yet to rigorously plumb the moment-by-moment dynamics anticipated by theory. Here we used a novel combination of neuroimaging techniques to demonstrate that certain and uncertain threat recruit a common threat-anticipation circuit. Activity in this circuit and covert measures of distress showed similar patterns of context-dependent dynamics, exhibiting persistent increases when anticipating uncertain-threat encounters and transient surges just before certain encounters. These observations provide fresh insights into the neurobiology of fear and anxiety, laying the groundwork for more ambitious clinical and mechanistic research.

neuroscience↗

bioRxiv2023

Adolescent social anxiety is associated with diminished discrimination of anticipated threat and safety

Social anxiety--which typically emerges in adolescence--lies on a continuum and, when extreme, can be devastating. Socially anxious individuals are prone to heightened fear, anxiety, and the avoidance of contexts associated with potential social scrutiny. Yet most neuroimaging research has focused on acute social threat. Much less attention has been devoted to understanding the neural systems recruited during the uncertain anticipation of potential encounters with social threat. Here we used a novel fMRI paradigm to probe the neural circuitry engaged during the anticipation and acute presentation of threatening faces and voices in a racially diverse sample of 66 adolescents selectively recruited to encompass a range of social anxiety and enriched for clinically significant levels of distress and impairment. Results demonstrated that adolescents with more severe social anxiety symptoms experience heightened distress when anticipating encounters with social threat, and reduced discrimination of uncertain social threat and safety in the bed nucleus of the stria terminalis (BST), a key division of the central extended amygdala (EAc). Although the EAc--including the BST and central nucleus of the amygdala--was robustly engaged by the acute presentation of threatening faces and voices, the degree of EAc engagement was unrelated to the severity of social anxiety. Together, these observations provide a neurobiologically grounded framework for conceptualizing adolescent social anxiety and set the stage for the kinds of prospective-longitudinal and mechanistic research that will be necessary to determine causation and, ultimately, to develop improved interventions for this often-debilitating illness.

neuroscience↗

bioRxiv2023

RSV infection does not induce EMT

Respiratory syncytial virus (RSV) infection does not cause severe disease in most of us despite suffering from multiple RSV infections in our lives. However, infants, young children, older adults, and immunocompromised patients are unfortunately vulnerable to RSV-associated severe diseases. A recent study suggested that RSV infection causes cell expansion, resulting in bronchial wall thickening in vitro. Whether the virus-induced changes in the lung airway resemble epithelial-mesenchymal transition (EMT) is still unknown. Here, we report that RSV does not induce EMT in three different in vitro lung models: the epithelial A549 cell line, primary normal human bronchial epithelial cells, and pseudostratified airway epithelium. We found that RSV increases the cell surface area and perimeter in the infected airway epithelium, which is distinct from the effects of a potent EMT inducer, TGF-{beta}1-driven cell elongation--indicative of cell motility. A genome-wide transcriptome analysis revealed that both RSV and TGF-{beta}1 have distinct modulation patterns of the transcriptome, which suggests that RSV-induced changes are distinct from EMT.

microbiology↗

bioRxiv2023

Neuroticism/negative emotionality is associated with increased reactivity to uncertain threat in the bed nucleus of the stria terminalis, not the amygdala

Neuroticism/Negative Emotionality (N/NE)--the tendency to experience anxiety, fear, and other negative emotions--is a fundamental dimension of temperament with profound consequences for health, wealth, and wellbeing. Elevated N/NE is associated with a panoply of adverse outcomes, from reduced socioeconomic attainment to psychiatric illness. Animal research suggests that N/NE reflects heightened reactivity to uncertain threat in the bed nucleus of the stria terminalis (BST) and central nucleus of the amygdala (Ce), but the relevance of these discoveries to humans has remained unclear. Here we used a novel combination of psychometric, psychophysiological, and neuroimaging approaches to rigorously test this hypothesis in an ethnoracially diverse, sex-balanced sample of 220 emerging adults selectively recruited to encompass a broad spectrum of N/NE. Cross-validated robust-regression analyses demonstrated that N/NE is preferentially associated with heightened BST activation during the uncertain anticipation of a genuinely distressing threat (aversive multimodal stimulation), whereas N/NE was unrelated to BST activation during certain-threat anticipation, Ce activation during either type of threat anticipation, or BST/Ce reactivity to threat-related faces. It is often assumed that different threat paradigms are interchangeable assays of individual differences in brain function, yet this has rarely been tested. Our results revealed negligible associations between BST/Ce reactivity to the anticipation of threat and the presentation of threat-related faces, indicating that the two tasks are non-fungible. These observations provide a framework for conceptualizing emotional traits and disorders; for guiding the design and interpretation of biobank and other neuroimaging studies of psychiatric risk, disease, and treatment; and for informing mechanistic research. SIGNIFICANCE STATEMENTNeuroticism/Negative Emotionality (N/NE) is a core dimension of mammalian temperament. Elevated levels of N/NE confer risk for a panoply of adversities--from reduced wealth and divorce to depression and death--yet the underlying neurobiology remains unclear. Here we show that N/NE is associated with heightened activation in the bed nucleus of the stria terminalis (BST) during the uncertain anticipation of a genuinely distressing threat. In contrast, N/NE was unrelated to BST reactivity during the certain anticipation of threat or the acute presentation of threat-related faces, two popular probes of the emotional brain. These findings refine our understanding of what has been termed the single most important psychological risk factor in public health, with implications for on-going biobank and therapeutics research.

neuroscience↗

bioRxiv2022

Enhanced production of natural shiga toxin by overexpressing A subunit of Stx2e in Stx2e-producing Escherichia coli isolated in South Korea

This study explored the optimal culture conditions for maximizing shiga toxin production in Stx2e-producing Escherichia coli (STEC) 150229, isolated from porcine edema disease (ED), with the goal of preparing a Stx2e toxoid vaccine candidate. High cytotoxicity was observed for this strain [tissue culture cytotoxic dose 50% (104 TCCD50/100 {micro}l)] from 48 h after incubation. Stx2e was overexpressed by transforming pStx2e A into STEC 150229, resulting in the production of recombinant Stx2e A/B complex combined with intrinsic Stx2e B. The enhanced production of Stx2e was evaluated based on the level of cytotoxicity against Vero cells. The highest cytotoxicity (105 TCCD50/100 {micro}l) was observed with the samples of recombinant Stx2e A/B complex eluted with 500 mM imidazole at 48 h of incubation. In conclusion, the recombinant Stx2e A protein forms an active protein complex with the intrinsic Stx2e B component from STEC 150229, producing high levels of shiga toxin.

microbiology↗

bioRxiv2022

Mitochondrial TFAM in the Regulation of FOXP3+ T cell Mediated Maintenance of CD4+ T Cell Landscapes

Foxp3 regulatory T cells (Tregs) maintain immune homeostasis, yet the process that preserves their stability during aging remain unclear. Mechanistic progress has been hindered by models that ablate Tregs or delete Foxp3, which induce acute autoimmunity and prevent longitudinal study of physiological regulatory drift. Here, we establish a dose-dependent mitochondrial framework that preserves Treg lineage survival while permitting gradual metabolic attenuation. Using Treg-restricted TFAM modulation, a complementary haploinsufficient model, and whole-spleen single-cell profiling. We identify lineage-selective immune remodeling characterized by contraction of naive CD8 and follicular B-cell pools, alteration of CD4 states, expansion of activated Tregs, and emergence of neuroimmune stress linked transcriptional modules that parallel physiological aging. Mechanistically, mitochondrial insufficiency is associated with functional loss of FOXP3-centered chromatin coordination and enrichment of NF-{kappa}B/NFAT/AP-1 inflammatory and senescence programs while lineage identity remains detectable. Partial mitochondrial attenuation within Tregs alone is sufficient to drive chronic low-grade systemic inflammation, neuromuscular decline, gut microbial restructuring, and elevated microglial responsiveness without Treg depletion. Pharmacologic and microbiota-directed interventions partially reduce inflammatory tone and improve functional metrics. Together, our findings identify TFAM as a key regulator of immune aging and reveal that healthy mitochondrial function in Tregs is essential for protecting against inflammaging and age-associated functional decline.

immunology↗

bioRxiv2022

The chemokine receptor CXCR3 promotes CD8+ T cell-dependent lung pathology during influenza pathogenesis

While the role of CD8+ T cells in influenza clearance is established, their contribution to pathological lung injury is increasingly appreciated. To explore if protective versus pathological functions can be linked to CD8+ T cell subpopulations, we dissected their responses in influenza-infected murine lungs. Our single-cell RNASeq (scRNAseq) analysis revealed significant diversity in CD8+ T cell subpopulations during peak viral load vs. infection-resolved state. While enrichment of Cxcr3hi CD8+ T effector (Teff) subset was associated with a more robust cytotoxic response, both CD8+ Teff and CD8+ T central memory (TCM) exhibited equally potent effector potential. The scRNAseq analysis identified unique regulons regulating the cytotoxic response in CD8+ T cells. The neutralization of CXCR3 mitigated lung injury without affecting viral clearance. IFN-{gamma} was dispensable to regulate the cytotoxic response of Cxcr3hi CD8+ T cells. Collectively, our data imply that CXCR3 interception could have a therapeutic effect in preventing influenza-linked lung injury. TEASERThe CXCR3 expressing CD8+ T cell subset causes severe lung pathology and exacerbates disease severity without affecting viral clearance during influenza infection

immunology↗

bioRxiv2021

Cellular heterogeneity and molecular reprogramming of host response during influenza acute lung injury

Acute lung injury (ALI) caused by influenza A virus (IAV or influenza) manifests from dysregulated cellular interactions between hematopoietic and non-hematopoietic cells that develop into a pathologic host response. However, the lungs diverse cellular framework that dictates the pathologic host response and acute lung injury remains incompletely understood. We performed a single-cell RNA-seq (scRNA-seq) analysis of total lung cells in mice from severe influenza to examine the cellular heterogeneity and cell-specific regulation of host response. We observed that IAV infection resulted in significant myelopoiesis, predominantly monocyte, and macrophage subsets, which constituted over 50% of total immune cells. IAV infection resulted in the significant loss of endothelial and fibroblast cells, representing the most predominant non-hematopoietic cells and crucial to regulating inflammatory response and barrier integrity. We also show the cell-cell communication dynamics of interferon and chemokine signaling and global regulation of these responses in transition from homeostatic to IAV infection state. These data highlight a robust application of scRNA-seq technology in establishing the atlas of cellular heterogeneity from its homeostatic transition to infection state and the host response regulation in IAV-mediated lung pathology.

immunology↗