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Song, Y.

Publications and source records attributed to Song, Y..

At least 91 records · Page 5Linked to original sources

Lymphotoxin-driven cancer cell eradication by tumoricidal CD8+ tumor-infiltrating lymphocytes

Tumor-infiltrating lymphocyte (TIL) therapy is FDA-approved for patients with treatment-resistant advanced melanoma, but the TIL subpopulations critical for tumor eradication remains incompletely understood. Using patient-derived TIL-melanoma co-cultures, we identified and characterized a novel subset of CD8+ TIL, capable of class I HLA-independent cancer cell lysis. The lymphotoxin {beta} receptor (LT{beta}R) and interferon (IFN) sensing pathways were nominated as key determinants of TIL-mediated cancer cell killing from a whole-genome, loss-of-function CRISPR screen. Validation studies confirmed that dual LT{beta}R and IFN sensing is necessary and sufficient for cancer cell lysis, and that expanded CD8+ TIL express high lymphotoxin {beta} (LTB) and upregulate lymphotoxin (LTA) upon coculture with cancer cells. Leveraging paired scRNA-seq and scTCR-seq data, we confirmed that enrichment of LTB+CD8+ T cells is associated with clinical response to TIL, and that LTB+CD8+ TIL are expanded from putative neoantigen-reactive, LTBlo CD8+ T cells in resected tumors. SignificanceWe have uncovered a previously unrecognized mechanism of TIL-mediated tumor eradication, providing mechanistic insights into the role of LTBR/IFN signaling in TIL-mediated cancer cell killing, and potentially offering insights into novel strategies to isolate, enrich, and expand tumoricidal TIL or augment specific TIL functions to enhance tumor control.

cancer biology↗

Associations between canine temperament and salivary levels of cortisol and serotonin

Temperament influences canine behavior and helps determine a dogs suitability as a companion or working animal. Although several temperament assessment tools exist, many rely on subjective evaluations, highlighting the need for scientifically validated methods. This study evaluated the validity of the Wesen temperament test by examining its association with physiological biomarkers--salivary cortisol and serotonin. Twenty-four dogs (11 females and 13 males) completed a modified Wesen test comprising seven subtests: Unconscious Confidence, Sociality, Noise Stability, Movement Stability, Desire for Play and Predation, Behavior in Stressful Situations, and Separation. Saliva samples were collected pre- and post-assessment, and cortisol and serotonin levels were measured using ELISA. Hormonal levels and temperament scores were analyzed using correlation, regression, and Kruskal-Wallis tests. Pre-assessment cortisol levels were negatively correlated with total average temperament score and several subtest scores. Post-assessment cortisol levels showed significant negative correlations with total average scores and all subtests. Changes in cortisol levels from pre- to post-assessment were negatively associated with temperament scores. Dogs with higher temperament scores exhibited significantly higher serotonin levels than those with lower scores. These findings support the utility of temperament assessments validated through physiological markers and provide novel evidence linking canine temperament with endocrine function.

physiology↗

Functional Genomic Profiling of Schizophrenia-Associated Genes Reveals Key Microglial Regulators

Microglia are increasingly recognized as key regulators of neural circuit development and putative contributors to the pathophysiology of neuropsychiatric disorders such as schizophrenia (SCZ). However, the functional impact of SCZ-associated genes in microglia remains largely unexplored. Here, we performed an arrayed CRISPR targeting screen of 30 schizophrenia-associated genes predicted to be differentially expressed in human microglia-like cells. Target genes were prioritized based on post-mortem transcriptomic relevance and predicted ontology-based roles in phagocytosis pathways. We quantified phagocytic activity and morphological changes following gene targeting using high-content confocal imaging. Key targets, including CYFIP1, MSR1, TREM2, SYK, ITGB2, ITGAM and IRF8, modulated phagocytosis and altered morphological properties consistent with activation states, validating their functional roles in microglia. To elucidate transcriptional impact, we further applied a multiplexed RNA sequencing platform across gene targets. These analyses revealed gene-specific transcriptional signatures, implicating divergent pathways related to phagocytic, activation, cytoskeletal, and lysosomal function. Together, these findings demonstrate the utility of CRISPR-based functional genomics in characterizing microglia function and identifying new target genes and mechanisms that may underlie their contributions to schizophrenia pathophysiology.

neuroscience↗

Simple Methods to Acutely Measure Multiple Timing Metrics among Sexual Repertoire of Male Drosophila

Male Drosophila courtship behavior is a key model for studying temporal decision-making. While courtship index (CI) is widely used to quantify mating activity, other timing metrics like courtship latency, copulation latency (CL), and mating duration (MD) remain understudied. Traditional methods for quantifying these behaviors are often labor-intensive and prone to human error. In this study, we present a protocol combining a modular chamber system and automated software (DrosoMating) to quantify 6 key timing metrics during male courtship. Our image-based video analysis enables precise identification of courtship and copulation events, as well as quantification of their timing and duration under controlled conditions. Validation shows <0.05% error rates and 98-99% agreement with manual scoring for CL, CI, and MD. The protocol supports genetic and neural circuit manipulations, detecting subtle genetic, social, and environmental behavioral variations. By minimizing manual effort and standardizing data collection, this approach facilitates scalable, reproducible studies on adaptive trade-offs, learning, and neural mechanisms in mating behavior. This method streamlines timing analysis in male courtship, offering reproducible metrics for behavioral genetics. HighlightA high-throughput software pipeline for automated temporal profiling of Drosophila melanogaster mating behavior after brief user-guided calibration. An accompanying, open-hardware platform that can be assembled at minimal cost while maintaining experimental rigor. The system attains near-manual accuracy and outputs Temporal Measurement Parameters data that are readily adaptable to--and quantifiable within--diverse behavioral paradigms.

developmental biology↗

Lightweight open-source fine-tuning of SAM2 enables domain-specific microscopy segmentation

Quantitation of structures is a critical step in analyzing images. Automated segmentation of biological samples remains a central challenge in microscopy, where variations in signal/noise, intensity, texture, and edges hinder accurate delineation of cellular and tissue structures. Adaptations of foundation models such as Segment Anything Model (SAM) remain computationally intensive and require large training datasets. Here, we introduce a lightweight, open-source Google Colab pipeline that enables efficient fine-tuning of SAM2 on domain-specific datasets without additional architectural layers or specialized hardware. By coupling mask-decoder fine-tuning with biologically informed post-processing, our framework achieves robust segmentation across diverse imaging modalities. Applied to hippocampal segmentation in brain images and single-cell segmentation in cell images, fine-tuned SAM2 demonstrates substantial gains of accuracy relative to basic SAM2 and matches leading tools. This work establishes a scalable and accessible paradigm for domain-specific adaptations of SAM2 in microscopy, lowering computational and data barriers to advanced image segmentation. HighlightsO_LILightweight fine-tuning with no added architectural complexity. C_LIO_LIHigh segmentation accuracy (Dice/Jaccard scores) achieved with small datasets. C_LIO_LICross-domain generalization across tissue and cell imaging with biologically informed post-processing. C_LIO_LIComparable or superior performance to widely used tools (Cellpose, Imaris, ilastik) at substantially lower computational cost. C_LIO_LIOpen-source and executable in a single Colab notebook, ensuring reproducibility and accessibility for non-computational users. C_LIO_LITurnkey adaptability, allowing researchers to transform raw microscopy data into fine-tuned SAM2 models with minimal input. C_LI

cell biology↗

Endothelial-targeted CD39 prevents Toxin-induced Pulmonary Hypertension Mice.

Disruption of the pulmonary endothelium by drugs, toxins, viruses (e.g., COVID-19), or bacterial sepsis can cause acute pulmonary vasculopathy leading to pulmonary hypertension and consequential heart failure. CD39 is a membrane-anchored ecto-enzyme expressed on endothelial cells (EC), integral in maintaining the antithrombotic profile of the endothelium. This ecto-enzyme works in concert with CD73 to hydrolyze both eATP (pro-inflammatory) and ADP (pro-thrombotic) ultimately to adenosine, which is anti-inflammatory, vasodilatory, and antithrombotic. CD39 activity and adenosine signalling are disrupted in idiopathic pulmonary arterial hypertension (PAH). In this work, we explored the efficacy of endothelial cell-targeted delivery of CD39 to prevent the development of acute toxin-induced PAH in a mouse model. We generated a novel therapeutic anti-VCAM-CD39 containing an scFv recognising VCAM-1 (a receptor expressed on activated EC) fused to the soluble form of extracellular human CD39. In a mouse model of endothelial cell-toxin-induced PAH, we show that a single administration of anti-VCAM-CD39 (0.4 mg/kg IV) prevented the development of PAH-- as reflected in the preservation of right ventricular systolic pressures and the absence of right ventricular hypertrophy at day 10 when compared with controls. This protection is conferred by multiple mechanisms: IL-10-driven potentiation of heme oxygenase (HO)-1, a known inhibitor of smooth muscle proliferation; VCAM-1 blockade reduces leukocyte adhesion to the endothelium; and cytoprotective effects through adenosine signalling. Thus, anti-VCAM-CD39 is a novel bifunctional therapeutic strategy for PAH.

physiology↗

A multi-tissue atlas of genetic regulatory effects in sheep

Characterizing the impact of genomic variants on genome function and ultimately complex traits in livestock is essential for the development of sustainable precision agriculture and comparative genomics. Here, as part of the Farm animal Genotype-Tissue Expression (FarmGTEx) project, we present the pilot phase of the SheepGTEx resource through analyzing 6,761 RNA-sequencing samples of 51 primary tissues in a multi-breed population of sheep. We identify millions of regulatory variants associated with seven types of molecular phenotypes, and fine-map 322,468 primary and 114,017 non-primary effects, revealing a high degree of regulatory allelic heterogeneity. We systematically characterize the pleiotropic effects of these variants on molecular phenotypes, assess their context-specific regulatory patterns across tissues, breeds, sexes, and developmental stages, as well as explore their evolutionary constraints across mammals. Finally, we demonstrate the substantial potential of the SheepGTEx resource (https://sheepgtex.farmgtex.org), by providing examples of regulatory mechanisms underpinning 34 complex traits, population divergence between European and Asian breeds, and adaptive evolution in sheep over the past ten millennia.

genomics↗

Agro-STARR-seq enables in planta genome-wide enhancer discovery and AI-empowerd enhancer design

Comprehensive enhancer screening is essential for dissecting gene regulatory networks. However, methods for such screening remain limited in plants. We present Agro-STARR-seq, an in planta enhancer screening platform using Agrobacterium-mediated delivery of STARR-seq libraries into Nicotiana benthamiana leaves. In the Arabidopsis genome, we identified 14,715 sequences with enhancer activity, of which 91.59% were located outside of open chromatin regions. This largest in planta enhancer dataset to date enabled AI-assisted design of highly active synthetic enhancers. For the large N. benthamiana genome, we pre-processed the genomic DNA with an Assay for Transposase Accessible Chromatin (ATAC) procedure before the Agro-STARR-seq protocol,and found that only one-third of open chromatin exhibited enhancer activity, 76.00% of which showed no canonical H3K27ac histone marks. Footprinting analysis further enables systematic linkage of transcription factor (TF) binding to enhancer function. Overall, Agro-STARR-seq provides a novel platform for dissecting and engineering plant enhancers.

genomics↗

Trait motivation is associated with Fusiform face area Morphometry Evidence from a Chinese Youth Sample

Trait motivation is fundamental in shaping human behaviors. Previous studies have primarily focused on their impact on affective and motivational processing, with their role in perceptual processes less investigated. The present study takes face perception, a crucial and well-studied perceptual process, as a representative specimen to examine the perceptual effect of trait motivation. We investigated whether the behavioral activation system (BAS) and the behavioral inhibition system (BIS) were associated with structural characteristics of the inferior temporal face-selective regions as well as face recognition performance. With a sample of Chinese young adults (N = 264), voxel-based morphometry revealed that BIS scores correlated with greater gray matter volume in the fusiform face area. Further, a higher BIS score was associated with slightly better performance in face recognition. These findings provide novel evidence that trait motivation, particularly behavioral inhibition, is linked to both the structure and function of the face processing system. This underlines the intrinsic coupling between motivational and perceptual systems, blurring the presumed divide between affective and perceptual processes.

neuroscience↗

ETV4 restrains the formation of CD74+ cytotoxic exhausted CD8+ T cells

Exhausted CD8+ T (Tex) cells comprise heterogeneous subsets with varying cytotoxic and dysfunctional properties, making inhibitory receptor profiles unreliable indicators of function. Therefore, it is essential to define transcriptional regulators or markers that accurately reflect these states. Here, we identified ETS variant 4 (ETV4) as a transcription factor that restricts cytotoxic Tex differentiation within tumors. ETV4 deficiency promotes the emergence of a CD74+ cytotoxic Tex subset while preserving the progenitor Tex (Tpex) pool. CD74 serves as both a marker and regulator, reinforcing Tpex features and enhancing Tex cytotoxicity. Mechanistically, ETV4 loss derepresses T-bet expression, thereby increasing IFN{gamma} production that induces CD74 expression in a paracrine manner. Single-cell analyses across human cancers revealed that CD74+ Tex cells are enriched for proliferative and metabolic programs and correlate with improved survival. Collectively, we establish the ETV4-CD74 axis as a regulator of Tex fate and promising therapeutic target to augment anti-tumor immunity.

immunology↗

Chronic Ethanol Drinking Alters Medial Prefrontal Cortex and Nucleus Accumbens Astrocyte Translatome and Extracellular Matrix Glycosaminoglycans

Alcohol Use Disorder is a leading preventable cause of morbidity and mortality, yet knowledge of mechanisms driving ethanol-related neuroplasticity remains incomplete. While research has traditionally focused on neuronal signaling, emerging evidence implicates astrocytes in addiction-related adaptations. Here, we investigated the astrocyte-specific molecular consequences of chronic ethanol consumption in the prefrontal cortex and nucleus accumbens, two brain regions critical for executive control and reward processing. Using Translating Ribosome Affinity Purification RNA-seq and bulk RNA-seq in Aldh1l1-EGFP/Rpl10a mice, expressing an EGFP tag on astrocyte ribosomes, we identified hundreds of differentially translated astrocytic genes following chronic continuous two-bottle choice ethanol drinking. Sex-specific analyses revealed greater astrocytic changes in the female PFC and male NAc. Pathway enrichment highlighted extracellular matrix remodeling, synaptic signaling, mitochondrial function, and immune-related pathways. Analyses of individual drinking levels further demonstrated distinct correlations between ethanol intake and astrocytic translation. The major components of the brain extracellular matrix are chondroitin sulfate proteoglycans, produced primarily by astrocytes and covalently bound to chondroitin sulfate glycosaminoglycan chains. Complementary mass spectrometry/liquid chromatography analyses of chondroitin sulfate, heparan sulfate, and hyaluronic acid glycosaminoglycan disaccharides revealed ethanol-induced alterations in chondroitin sulfate glycosaminoglycan sulfation patterns, with additional baseline differences identified between selectively bred high- and low-ethanol preference lines. Together, these findings indicate that astrocytes undergo profound sex- and region-specific adaptations to chronic ethanol, implicating extracellular matrix and glycosaminoglycan remodeling as key risk-factors for and mediators of chronic ethanol-related neuroplasticity.

neuroscience↗

Study of Sex Differences in the Whole Brain White Matter Using Diffusion MRI Tractography and Suprathreshold Fiber Cluster Statistics

Sex-specific characteristics demonstrate a substantial influence on the brain white matter (WM), suggesting distinct structural connectivity patterns between females and males. Diffusion MRI (dMRI) tractography is an important tool in assessing WM connectivity and brain tissue microstructure across different populations. Whole brain tractography analysis for group statistical comparison is a challenging task due to the large number of WM connections. This work studies whole-brain WM connectivity differences between females and males using dMRI tractography. We study a large cohort of 707 subjects from the Human Connectome Project Young Adult dataset. By applying a well-established fiber clustering pipeline and a suprathreshold fiber cluster statistical method, we analyze tracts in the cerebral cortex and understudied pathways like those connecting to the cerebellum. We identify several tracts with significant sex differences in terms of their fractional anisotropy and/or mean diffusivity. These include deep tracts like the arcuate fasciculus, corticospinal tract, and corpus callosum, superficial tracts in the frontal lobe, and cerebellar tracts. Finally, correlation analysis reveals that these WM differences are linked to a range of neurobehavioral measures, with the strongest and most consistent associations observed for motor function, suggesting motor circuits as a potential key focus for future research.

neuroscience↗

A Generative Foundation Model for Antibody Design

Antibodies are indispensable components of the immune system, yet the design of high-affinity antibodies remains a time-consuming and experimentally intensive process. To address this challenge, we present IgGM, a novel generative foundation model designed to accelerate high-affinity antibody engineering. IgGM learns the complex relationships underlying the binding interactions between antigens and antibodies, as well as the mapping between antibody sequences and structures. By conditioning on different inputs, IgGM supports a wide range of antibody design tasks, including complex structure prediction, inverse design, affinity maturation, framework optimization, humanization, and de novo antibody design. It is compatible with both conventional antibodies and nanobodies, and allows user-defined CDR loop lengths for flexible design. To prioritize candidates, we introduce a frequency-based computational screening strategy that enhances design efficiency. Extensive evaluation through both in silico benchmarks and in vitro experiments across diverse antigens such as PD-L1, Protein A, TNF-, IL-33, SARS-CoV-2 RBD and its variants demonstrates that IgGM consistently generates antibodies or nanobodies with high measured affinity. These results underscore IgGMs versatility and effectiveness as a powerful tool for next-generation antibody discovery and optimization.

bioinformatics↗

Hypoimmunogenic human motor neurons induced from iPSCs in vivo substantially ameliorate ALS disease in large animal models

Stem cell-based therapy holds great potential for substituting degenerated motor neurons (MNs) in amyotrophic lateral sclerosis (ALS). Missing protocols for advanced differentiation of transplanted cells into MNs, immune rejection, and the lack of suitable ALS models for preclinical trials have slowed the development of effective therapies. Here, we employed multiplex genetic-editing to generate a novel human pluripotent stem cell line containing doxycycline (Dox)-inducible MNs-specific transcription factors and comprehensively modified immunomodulatory genes. We transplanted these cells into the spinal cord of ALS large animal models (SOD1G93A pigs and TIA1P362L rabbits), which faithfully recapitulate pathologies and symptoms observed in ALS patients. The transplanted cells could efficiently differentiate into functional MNs upon Dox treatment in vivo, distribute throughout the spinal cord and motor cortex via extensive migration, survive long-term without the need for immunosuppression. Notably, these MNs integrated into host neural circuits, as evidenced by their long projection of peripheral axons to target muscle and reformation of neuromuscular junctions. As result, pathologies and motor deficits were substantially ameliorated in both animal models. One Sentence SummaryHypoimmunogenic human motor neurons induced from iPSCs in vivo reform neuromuscular junctions and ameliorate ALS disease in pig and rabbit models.

neuroscience↗

Direct contact between iPSC-derived macrophages and hepatocytes drives reciprocal acquisition of Kupffer cell identity and hepatocyte maturation

Hepatic macrophages play central roles in liver homeostasis, injury, and immune-mediated hepatotoxicity through dynamic crosstalk with hepatocytes. While monocyte-derived macrophages have been widely used in vitro, they do not fully recapitulate the biology of liver-resident Kupffer cells (KCs), which are embryonically derived and maintained locally. Recent advances suggest that induced pluripotent stem cell (iPSC)-derived macrophages (iMacs) more closely resemble embryonic macrophages and may therefore serve as a relevant platform to model KC biology. Here, we developed a human iPSC-based co-culture system by combining iMacs with iPSC-derived hepatocytes (iHeps) derived from the same donor, enabling direct cell-cell interactions. We hypothesized that such interactions would both enhance hepatocyte maturation and promote KC-like differentiation of iMacs. Indeed, co-culture induced KC-like phenotypes in iMacs and improved functional maturation of iHeps, highlighting the importance of bidirectional cellular communication. Comparative analyses with iMacs cultured in hepatocyte-conditioned media revealed that direct contact provides additional signals beyond soluble factors in driving hepatic macrophage specialization. Functionally, this co-culture system demonstrated improved physiological relevance, particularly in modeling immune-mediated drug responses, as evidenced by enhanced cytokine production profiles upon exposure to a panel of test compounds. Overall, this study establishes a novel human iPSC-derived platform that captures key aspects of hepatocyte-macrophage crosstalk, providing a more physiologically relevant model to investigate liver biology and assess immune-mediated drug toxicity.

immunology↗

Dominance of plasticity in wind-pollinated trees' flowering time response to temperature

Climate change is shifting the flowering phenology of wind-pollinated trees, leading to longer pollen seasons and heightened allergy risks. Accurately forecasting these phenological shifts requires a clear understanding of the underlying mechanisms and variations in the sensitivity of phenology to temperature. Here, we investigated the temperature sensitivity of flowering phenology in 74 wind-pollinated tree species across the US using long-term herbarium records spanning over a century. We found consistent phenological responses to spring temperature variations over space and over time in 77% of species, indicating that these long-lived trees can rely primarily on plasticity to cope with temperature variation across different regions. Sensitivity estimates were consistent across both century-scale and decadal time scales, challenging the previous understanding of declines. Interspecific variations in sensitivity exhibited a strong phylogenetic signal, indicating evolutionary conservatism in phenological responses among related species. Together, these findings shed light on the magnitude, mechanism, trend, and variability of temperature sensitivity of wind-pollinated tree flowering phenology. Our results improve the mechanistic basis for forecasting phenological shifts and their downstream effects on airborne pollen and allergen exposure under ongoing climate change.

ecology↗

UHRF1 restricts HCoV-229E infection through epigenetic silencing of the viral receptor APN

The emergence of SARS-CoV-2 has posed significant threats to global health, particularly for the older population. Similarly, common human coronaviruses, such as HCoV-229E, which typically cause mild cold-like symptoms, have also been linked to severe diseases, underscoring the need to understand virus-host interactions and identify host factors contributing to viral pathogenesis and disease progression. In this study, we performed a genome-wide CRISPR knockout screen using HCoV-229E and identified Ubiquitin-like with PHD and RING finger domain 1 (UHRF1) as a potent restriction factor. Mechanistically, UHRF1 suppressed HCoV-229E infection by downregulating the expression of its cell entry receptor, aminopeptidase N (APN), through promoter hypermethylation. Focused CRISPR activation screens of UHRF1-downregulated genes confirmed the critical role of APN in HCoV-229E infection and identified additional genes (e.g., SIGLEC1, PLAC8, and heparan sulfate biosynthesis genes) contributing to the restrictive functions of UHRF1. Transcriptomic and single-cell RNA sequencing analysis revealed that UHRF1 expression decreases with age, negatively correlating with increased APN expression. This age-related decline in UHRF1 was further validated in primary alveolar macrophages isolated from elderly individuals, which exhibited heightened susceptibility to HCoV-229E infection compared to those from younger individuals. Our findings highlight UHRF1 as a key age-related host defense factor against coronavirus infection and provide novel insights into the epigenetic regulation of viral entry receptors.

microbiology↗

The global phylogeography of rapidly expanding multidrug resistant Ural lineage 4.2 Mycobacterium tuberculosis

Multidrug resistant tuberculosis (MDR-TB) is a leading global health challenge. Recent studies identified a reproductively fit Ural lineage 4.2 MDR M. tuberculosis (Mtb) variant circulating within the Republic of Moldova. We searched a large publicly available dataset of [~]200,000 Mtb whole genome sequences and identified a clade of 1604 drug-resistant Mtb sequences harboring conserved resistance-conferring mutations that are closely related to the MDR Mtb variant circulating in Moldova. We identified the Russian Federation as the most likely country of origin for this clade, and we inferred several independent migration events from Russia and Moldova to other former Soviet Republics and several European countries. Using local branching index, we found that this clade is expanding more rapidly than comparable clades of lineage 4.2. This evolutionarily successful strains presence beyond Moldova poses a threat to MDR-TB control, and enhanced surveillance is necessary to reduce the risk of MDR-TB epidemics in the region. FundingThe authors report funding from the National Institutes of Health (R01AI180209, P01AI159402)

microbiology↗