bioRxiv Science⌕ Search

Biology subjects

Yun, K.

Publications and source records attributed to Yun, K..

At least 19 recordsLinked to original sources

Female-Biased IL-17/STAT3 Signaling Marks Dementia-Associated Microglial Inflammation in Alzheimer's Disease

INTRODUCTION: Alzheimer's disease (AD) disproportionately affects women, but the underlying mechanisms are not fully understood. We compare sex-specific molecular changes across AD with and without dementia at single-cell resolution. METHODS: We performed sex-stratified single-nucleus transcriptomic analysis of human AD to dissect sex-specific differences in dementia progression, using the SEA-AD cohort for discovery and the ROSMAP and NBB datasets, together with 5xFAD mouse models, for validation. Donors were classified as no-dementia controls, no-dementia AD, or dementia AD, followed by donor-level pathway analysis, de novo microglial clustering, communication modeling, and cytokine-response enrichment RESULTS: Females with AD dementia showed enhanced inflammatory pathway activity across glial, neuronal and vascular-associated cell types, with the strongest enrichment in microglia. This female-biased program centered on IL6-JAK-STAT3 signaling and increased STAT3 expression in microglia and astrocytes. These results were validated in the ROSMAP and NBB datasets and conserved in the 5xFAD mouse model. Microglial clustering resolved 18 states and revealed sex-divergent disease remodeling, including female-specific expansion of redox-reactive and CD163+ macrophage-primed states. Cell:cell communication analysis identified female-biased TGF{beta}/GRN signaling, male-biased CD99 signaling, and dementia-associated SPP1-integrin communication with the vasculature. Microglial cytokine-response analysis identified IL-2 response as a dementia-associated signature in both sexes, alongside a female-biased IL-17/interferon response and a male-biased IL-7 response. DISCUSSION: These findings identify a disease-emergent, female-biased STAT3-centered neuroinflammatory program in human and mouse AD, linking sex-specific microglial remodeling to cytokine responsiveness and glial-vascular communication. The results suggest that sex-specific changes in neuroinflammation pathways in microglia and other cell types are associated with progression to dementia.

neuroscience↗

Ex vivo human tumor slices more accurately predict patient responses to an oncolytic virus than in vivo mouse models

Immunotherapies, including oncolytic viruses (OV), are promising therapies that can enhance anti-tumor immune responses. However, preclinical success of immunotherapies in mouse models has not always translated to clinical benefit in cancer patients. This study compared preclinical efficacy and mechanism of action for ASP9801, a vaccinia virus expressing IL-7 and IL-12, using mouse models of colorectal cancer (CRC) in vivo and in human organotypic tumor slice models ex vivo. The murine surrogate for ASP9801 significantly reduced tumor volumes in treated and abscopal tumors in two different CRC models in vivo (MC38 and RO100). Treatment efficacy was accentuated when combined with anti-PD1 treatment, and single-cell RNA sequencing analysis revealed depletion of tumor cells and increased T cell infiltration and activation in both treated and abscopal tumors. However, human tissue analysis ex vivo (E-slices) using PDX models and patient samples showed that ASP9801 is not effective in CRC, consistent with clinical trial results. On the other hand, ASP9801 was highly effective in GBM, indicating indication-specific efficacy of ASP9801, and how E-slice assays can be used to identify treatment-sensitive indications. This study demonstrates the superiority of E-slices over mouse models for predicting clinical response and its utility in planning clinical trials.

cancer biology↗

Midkine Dependency Defines a Therapeutically Actionable Vulnerability in Medulloblastoma

Medulloblastoma (MB), the most common malignant pediatric brain tumor, remains associated with high recurrence rates and substantial treatment-related morbidity despite aggressive multimodal therapy. Here, we identify midkine (MDK), a secreted growth factor/cytokine, as a previously unrecognized central regulator of MB growth and survival. Tissue microarray analysis revealed elevated MDK protein expression in MB specimens, and single-cell RNA sequencing datasets showed tumor cell-specific MDK expression. Genetic depletion or antibody-mediated neutralization of MDK suppressed proliferation and survival and induced apoptosis across multiple MB cell lines, whereas recombinant MDK supplementation exerted the opposite effect. Mechanistically, phosphokinase profiling and immunoblot analyses showed that MDK signals through multiple receptors, including nucleolin (NCL), LRP1, and syndecan-2 (SDC2), to sustain oncogenic ERK1/2 and Akt-mTOR-S6 signaling. Transcriptomic profiling following MDK silencing or depletion revealed marked suppression of ribosome biogenesis, global protein translation, and MYC-driven programs, coupled with activation of inflammatory and apoptotic responses. Consistently, mechanistic studies utilizing RPS6 staining, ribosomal RNA quantification, puromycin SUnSET, and OPP incorporation assays confirmed that loss of MDK impairs ribosome biogenesis and protein synthesis. Notably, MDK suppression also triggered robust activation of the IFN-cGAS-STING pathway, linking translational stress to innate immune signaling. In orthotopic xenograft models, CRISPR-mediated MDK knockout significantly reduced tumor growth and prolonged survival. Together, these findings establish MDK as a key integrator of oncogenic signaling, translational control, and innate immunity in MB, highlighting MDK as a compelling therapeutic target.

cancer biology↗

Rictor CRISPR Gene Editing by Lipid Nanoparticle Delivery Stimulates Anti-Tumor Immunity in Breast Cancer Liver Metastasis Model

Triple-negative breast cancer (TNBC) is a highly aggressive subtype, accounting for 10-15% of breast cancer cases in the United States. Liver metastases, common in advanced TNBC, are linked to especially poor outcomes, with a 5-year survival rate of just 11%. Although immune checkpoint inhibitors (ICIs) targeting PD-1 or PD-L1 show promise, durable responses in TNBC remain uncommon. This is largely due to a profoundly immunosuppressive tumor microenvironment (TME), driven by tumor-associated myeloid cells. Tumor-associated macrophages (TAMs) and neutrophils (TANs) polarize into immunosuppressive M2 and N2 phenotypes, respectively, suppressing T cell activity through cytokines, ROS, and checkpoint ligands such as VISTA. Myeloid-derived suppressor cells (MDSCs) further inhibit immunity by depleting nutrients and inducing regulatory T cells. As a result, despite its immunogenic features, TNBC remains resistant to immunotherapy due to persistent myeloid-mediated suppression. Here, we developed ionizable lipid nanoparticles (iLNPs) engineered to deliver the CRISPR-Cas12a ribonuclease complex targeting Rictor, a critical component of mTORC2, for in vivo reprograming of myeloid cells. The intravenous (IV) injection of CRISPR Rictor-targeting iLNP (CR-Ric-LNP) showed efficient uptake by circulating myeloid cells and accumulation into the breast cancer liver metastases. Notably, Rictor gene editing triggered pro-inflammatory activation of myeloid cells in the TME, enhancing antitumor responses. Single-cell RNA sequencing revealed that Rictor silencing treated samples showed induced rapid remodeling of the TME, with a significant reduction in immunosuppressive macrophages within 24 hours of treatment. Concurrently, cytotoxic T-cell populations exhibited increased interferon-gamma (Ifng) production, driving the emergence of specific myeloid clusters that were responsive to Interferon signaling, particularly in macrophages and neutrophils. A shift from an immunosuppressive to an inflammatory TME was further evidenced by an elevated Cxcl10/Spp1 ratio in myeloid cells. CR-Ric-LNP treatment also enhanced T-cell activation, reducing exhausted T cells and regulatory T cells (Tregs) while expanding natural killer (NK) cells, naive CD4+, and CD8+ T cells. These changes correlated with a decreased proportion of tumor cells and proliferating cells, ultimately leading to a significant survival benefit in a 4T1 breast cancer liver metastasis model. Our findings demonstrate that myeloid-targeted Rictor silencing reprograms the TME, promoting antitumor immunity and improving therapeutic outcomes. O_FIG O_LINKSMALLFIG WIDTH=199 HEIGHT=200 SRC="FIGDIR/small/661471v1_ufig1.gif" ALT="Figure 1"> View larger version (109K): org.highwire.dtl.DTLVardef@10a5e7aorg.highwire.dtl.DTLVardef@1c0c005org.highwire.dtl.DTLVardef@17ec6b5org.highwire.dtl.DTLVardef@27c507_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Combined inhibition of S100A4 and TIGIT suppresses late-stage breast cancer metastasis to the lung by activating T and NK cells

Cancer metastasis is responsible for approximately 90% of cancer-related deaths, but very few treatment options exist currently. While the role of S100A4 in promoting metastasis has been known for decades, this knowledge has not been translated in the clinic. Here, we report that a novel monoclonal antibody against the human S100A4 protein (S1004-11) effectively suppresses breast cancer metastasis in two different mouse models. Importantly, a novel combination of ant-TIGIT and S100A4-11 can suppress lung metastases even in late-stage disease after the lung premetastatic niche (PMN) has already been established similar to a stage when many breast cancer patients are diagnosed. Mechanistically, S1004-11 mAb treatment block the formation of PMN by suppressing neutrophil infiltration and activating natural killer (NK) and T cells in the lung. Single-cell RNA-sequencing and cell:cell communication analyses indicate that TIGIT signaling suppresses NK cells, which is reversed in S100A4-11 treated PMN. In summary, this study provides compelling evidence for a novel mechanism of S100A4 function in PMN formation and the feasibility of using S100A4-11 monoclonal antibody to suppress metastases at different stages of breast cancer progression.

cancer biology↗

Optimized CART Cell Therapy for Metastatic Aggressive Thyroid Cancer

Most thyroid cancer deaths are attributed to a subset of poorly differentiated, metastatic tumors. To improve treatment options for aggressive thyroid cancers, we developed a novel thyroid-stimulating hormone receptor (TSHR)-targeted chimeric antigen receptor T (CART) cell therapy, which demonstrated antigen-specific activation and antitumor efficacy against TSHR+ cell lines in vitro and in vivo. However, de-differentiated thyroid cancers downregulate TSHR. We therefore developed a potent treatment strategy by combining our novel TSHR-CART cells with mitogen-activated protein kinase (MAPK) inhibitors, which redifferentiate thyroid tumors and upregulate TSHR expression. In patient-derived anaplastic thyroid cancer xenografts, combination therapy of TSHR-CART cells and MAPK inhibitors led to increased TSHR expression on the tumor tissue and significantly enhanced antitumor efficacy and prolonged survival compared to TSHR-CART monotherapy. Based on our data, we are launching a phase I clinical trial for TSHR-CART cell therapy alone or in combination with MAPK inhibitors in patients with metastatic thyroid cancers. STATEMENT OF SIGNIFICANCEPoor target selection and antigen escape limit CART cell efficacy in solid tumors. We developed TSHR-CART cells to treat differentiated thyroid cancers but observed TSHR downregulation in dedifferentiated thyroid cancers. We found that MAPK inhibitors restored TSHR expression and sensitized these cancers to TSHR-CART cell therapy.

immunology↗

Involvement of ArlI, ArlJ, and CirA in Archaeal Type-IV Pilin-Mediated Motility Regulation

Many prokaryotes use swimming motility to move toward favorable conditions and escape adverse surroundings. Regulatory mechanisms governing bacterial flagella-driven motility are well-established, however, little is yet known about the regulation underlying swimming motility propelled by the archaeal cell surface structure, the archaella. Previous research showed that deletion of the adhesion pilins (PilA1-6), subunits of the type IV pili cell surface structure, renders the model archaeon Haloferax volcanii non-motile. In this study, we used EMS mutagenesis and a motility assay to identify motile suppressors of the {Delta}pilA[1-6] strain. Of the eight suppressors identified, six contain missense mutations in archaella biosynthesis genes, arlI and arlJ. Overexpression of these arlI and arlJ mutant constructs in the respective multi-deletion strains {Delta}pilA[1-6]{Delta}arlI and {Delta}pilA[1-6]{Delta}arlJ confirmed their role in suppressing the {Delta}pilA[1-6] motility defect. Additionally, three suppressors harbor co-occurring disruptive missense and nonsense mutations in cirA, a gene encoding a proposed regulatory protein. A deletion of cirA resulted in hypermotility, while cirA overexpression in wild-type cells led to decreased motility. Moreover, qRT-PCR analysis revealed that in wild-type cells, higher expression levels of arlI, arlJ, and the archaellin gene arlA1 were observed in motile early-log phase rod-shaped cells compared to non-motile mid-log phase disk-shaped cells. Conversely, {Delta}cirA cells, which form rods during both early and mid-log phases, exhibited similar expression levels of arl genes in both growth phases. Our findings contribute to a deeper understanding of the mechanisms governing archaeal motility, highlighting the involvement of ArlI, ArlJ, and CirA in pilin- mediated motility regulation. ImportanceArchaea are close relatives of eukaryotes and play crucial ecological roles. Certain behaviors, such as swimming motility, are thought to be important for archaeal environmental adaptation. Archaella, the archaeal motility appendages, are evolutionarily distinct from bacterial flagella, and the regulatory mechanisms driving archaeal motility are largely unknown. Previous research has linked the loss of type IV pili subunits to archaeal motility suppression. This study reveals three Haloferax volcanii proteins involved in pilin-mediated motility regulation, offering a deeper understanding of motility regulation in this understudied domain while also paving the way for uncovering novel mechanisms that govern archaeal motility. Understanding archaeal cellular processes will help elucidate the ecological roles of archaea as well as the evolution of these processes across domains.

microbiology↗

Halofilins as Emerging Bactofilin Families of Archaeal Cell Shape Plasticity Orchestrators

Bactofilins are rigid, non-polar bacterial cytoskeletal filaments that link cellular processes to specific curvatures of the cytoplasmic membrane. Although homologs of bactofilins have been identified in archaea and eukaryotes, functional studies have remained confined to bacterial systems. Here, we characterize representatives of two new families of archaeal bactofilins from the pleomorphic archaeon Haloferax volcanii, halofilin A (HalA) and halofilin B (HalB). HalA and HalB polymerize in vitro, assembling into straight bundles. HalA polymers are highly dynamic and accumulate at positive membrane curvatures in vivo, whereas HalB forms more static foci that localize in areas of local negative curvatures on the outer cell surface. Gene deletions and live-cell imaging show that halofilins are critical in maintaining morphological integrity during shape transition from disk (sessile) to rod (motile). Morphological defects in {Delta}halA result in accumulation of highly positive curvatures in rods but not in disks. Conversely, disk-shaped cells are exclusively affected by halB deletion, resulting in flatter cells. Furthermore, while {Delta}halA and {Delta}halB cells imprecisely determine the future division plane, defects arise predominantly during the disk-to-rod shape remodeling. In fact, the deletion of halA in the haloarchaeon Halobacterium salinarum, whose cells are consistently rod-shaped, impacted morphogenesis but not cell division. Increased levels of halofilins enforced drastic deformations in cells devoid of S-layer, suggesting that HalB polymers are more stable at defective S-layer lattice regions. Our results set halofilins apart from their bacterial correlate, where they provide mechanical scaffolding instead of directing envelope synthesis.

microbiology↗

The Identification of IL-4 as a Regulator of Chimeric Antigen Receptor T Cell Exhaustion

Durable response to chimeric antigen receptor T (CART) cell therapy remains limited in part due to CART cell exhaustion. We investigated the regulation of CART cell exhaustion with three independent approaches including: a genome-wide CRISPR knockout screen using a validated in vitro model for exhaustion, RNA and ATAC sequencing on baseline and chronically stimulated CART cells, and RNA and ATAC sequencing on pre-infusion CART cell products from responders and non-responders in the ZUMA-1 clinical trial. Each of these approaches identified IL-4 as a key regulator of CART cell dysfunction. Further, when CART cells were treated with IL-4, they developed signs of exhaustion, but when CART cells were treated with an IL-4 monoclonal antibody, they showed improved antitumor efficacy and reduced signs of exhaustion in preclinical models. Therefore, our study identified both a novel role for IL-4 on CART cells and the improvement of CART cell therapy through IL-4 neutralization. Statement of SignificanceIdentifying regulators of CART cell exhaustion will not only enhance the fields understanding of therapeutic failure, but it will also provide avenues to enhance CART cell efficacy. This study reveals both a novel role for IL-4 in exhaustion and a strategy to improve CART cell activity through IL-4 neutralization.

immunology↗

A prognostic matrix code defines functional glioblastoma phenotypes and niches.

Interactions among tumor, immune and vascular niches play major roles in driving glioblastoma (GBM) malignancy and treatment responses. The composition, heterogeneity, and localization of extracellular core matrix proteins (CMPs) that mediate such interactions, however, are not well understood. Here, we characterize functional and clinical relevance of genes encoding CMPs in GBM at bulk, single cell, and spatial anatomical resolution. We identify a "matrix code" for genes encoding CMPs whose expression levels categorize GBM tumors into matrisome-high and matrisome-low groups that correlate with worse and better survival, respectively, of patients. The matrisome enrichment is associated with specific driver oncogenic alterations, mesenchymal state, infiltration of pro-tumor immune cells and immune checkpoint gene expression. Anatomical and single cell transcriptome analyses indicate that matrisome gene expression is enriched in vascular and leading edge/infiltrative anatomic structures that are known to harbor glioma stem cells driving GBM progression. Finally, we identified a 17-gene matrisome signature that retains and further refines the prognostic value of genes encoding CMPs and, importantly, potentially predicts responses to PD1 blockade in clinical trials for GBM. The matrisome gene expression profiles may provide biomarkers of functionally relevant GBM niches that contribute to mesenchymal-immune cross talk and patient stratification to optimize treatment responses.

cancer biology↗

Sex-biased Yap1 oncogene function

The incidence of many human cancers differs according to sex, but little is known about the interplay between oncogenic events and sex as a variable in tumorigenesis. Here we report that the oncogene Yap1 is sexually dimorphic in medulloblastoma progression and immune suppression. We show that Yap1 promotes stemness and blocks differentiation in sonic hedgehog (SHH)-subtype medulloblastoma by at least two distinct but complementary molecular mechanisms to regulate the RNA expression and protein functions of Sox2, Atoh1, NeuroD1, and Zic1/2. Yap1 also promotes an immune suppressive tumor microenvironment by directly regulating Csf1, Igf1, and Igfbp3 transcription and modulating IL6-JAK-STAT3, TNFR1, TGF-{beta}, and CCL5 immune pathways. Notably, Yap1 function is more critical in males and this is evolutionarily conserved: genes downstream of YAP1 identified in mouse models stratify male but not female medulloblastoma patient survival. In summary, we demonstrate a sex-based function for an oncogene, underscoring the critical need to incorporate sex as a variable in cancer mechanism and clinical response studies, particularly those involving YAP1.

cancer biology↗

Cropbox: a declarative crop modeling framework

Crop models mirror our knowledge on crops in silico. Therefore, crop modeling inherits common issues of software engineering and often suffers from technical debts. We introduce a new crop modeling framework: Cropbox as a declarative domain-specific language. Recognizing that a crop model is fundamentally an integrated network of generalized state variables, we developed the framework to encapsulate abstract primitives for representing variables, systems, and functions that are essential to crop modeling workflows. With a constrained syntax, high-level model specifications are automatically translated into low-level host code written in Julia programming language. This allows complex crop models to become more accessible and transparent for modelers to build and use. We highlight key capabilities of the Cropbox framework through specific case studies featuring a coupled leaf gas-exchange model and a process-based crop simulation model. We also illustrate potential extensions of the framework to support functional-structural plant modeling (FSPM) using a 3D root architectural model as an example.

plant biology↗

An integrative process-driven model for biomass and yield estimation of hardneck garlic (Allium sativum)

We introduce an integrative process-driven crop model for garlic (Allium sativum). Building on our previous model that simulated key phenological, morphological, and physiological features of a garlic plant, the new garlic model provides comprehensive and integrative estimations of biomass accumulation and yield formation under diverse environmental conditions. This model also showcases an application of Cropbox to develop a comprehensive crop model. Cropbox is a crop modeling framework featuring declarative modeling language and unified simulation interface for building and improving crop models. Using Cropbox, we first evaluated the model performance against three datasets with an emphasis on biomass and yield measured under different environmental conditions and growing seasons. We then applied the model to simulate optimal planting dates under future climate conditions for assessing climate adaptation strategies between two contrasting locations in South Korea: the current growing region (Gosan) and an unfavorable cold winter region (Chuncheon, Gangwon-do). The model simulated the growth and development of a southern-type cultivar (Namdo, Jeju-do) reasonably well. Under RCP (Representative Concentration Pathway) scenarios, an overall delay in optimal planting date from a week to a month and a slight increase in potential yield were expected in Gosan. Expansion of growing region to northern area including Chuncheon was expected due to mild winter temperatures in the future and may allow Namdo cultivar production in more regions. The predicted optimal planting date in the new region was similar to the current growing region that favors early fall planting. Our new integrative garlic model provides mechanistic, process-driven crop responses to environmental cues and can be useful for assessing climate impacts and identifying crop specific climate adaptation strategies for the future.

plant biology↗

Robust T1 MRI cortical surface pipeline for neonatal brain and systematic evaluation using multi-site MRI datasets

The human brain grows the most dramatically during the perinatal and early postnatal periods, during which preterm birth or perinatal injury that may alter brain structure and lead to developmental anomalies. Thus, characterizing cortical thickness of developing brains remains an important goal. However, this task is often complicated by inaccurate cortical surface extraction due to small-size brains. Here, we propose a novel complex framework for the reconstruction of neonatal WM and pial surfaces, accounting for large partial volumes due to small-size brains. The proposed approach relies only on T1-weighted images unlike previous T2-weighted image-based approaches while only T1-weighted images are sometimes available under the different clinical/research setting. Deep neural networks are first introduced to the neonatal MRI pipeline to address the mis-segmentation of brain tissues. Furthermore, this pipeline enhances cortical boundary delineation using combined models of the CSF/GM boundary detection with edge gradient information and a new skeletonization of sulcal folding where no CSF voxels are seen due to the limited resolution. We also proposed a systematic evaluation using three independent datasets comprising 736 preterm and 97 term neonates. Qualitative assessment for reconstructed cortical surfaces shows that 86.9% are rated as accurate across the three site datasets. In addition, our landmark-based evaluation shows that the mean displacement of the cortical surfaces from the true boundaries was less than a voxel size (0.532{+/-}0.035mm). Evaluating the proposed pipeline (namely NEOCIVET 2.0) shows the robustness and reproducibility across different sites and different age-groups. The mean cortical thickness measured positively correlated with postmenstrual age (PMA) at scan (p<0.0001); Cingulate cortical areas grew the most rapidly whereas the inferior temporal cortex grew the least rapidly. The range of the cortical thickness measured was biologically congruent (1.3mm at 28 weeks of PMA to 1.8mm at term equivalent). Cortical thickness measured on T1 MRI using NEOCIVET 2.0 was compared with that on T2 using the established dHCP pipeline. It was difficult to conclude that either T1 or T2 imaging is more ideal to construct cortical surfaces. NEOCIVET 2.0 has been open to the public through CBRAIN (https://mcin-cnim.ca/technology/cbrain/), a web-based platform for processing brain imaging data.

bioinformatics↗

A cloud-based platform for the analysis of single cell RNA sequencing data.

MotivationSingle-cell RNA sequencing (scRNA-seq) is a recent technology that has provided many valuable biological insights. Notable uses include identifying novel cell-types, measuring the cellular response to treatment, and tracking trajectories of distinct cell lineages in time. The raw data generated in this process typically amounts to hundreds of millions of sequencing reads and requires substantial computational infrastructure for downstream analysis, a major hurdle for a biological research lab. Fortunately, the preprocessing step that converts this huge sequence data into manageable cell-specific expression profiles is standardized and can be performed in the cloud. We demonstrate how a cloud-based computational framework can be used to transform the raw data into biologically interpretable cell-type-specific information, using either 3 or 5 transcriptome libraries from 10x Genomics. The processed data which is an order of magnitude smaller in size can be easily downloaded to a laptop for customized analysis to gain deeper biological insights. ResultsWe produced an automated and easily extensible pipeline in the cloud for the analysis of single-cell RNA-seq data which provides a convenient method to handle post-processing of scRNA sequencing using next generation sequencing platforms. The basic step provides the transformation of the scRNA-seq data to cell-type-specific expression profiles and computes the quality control metrics for the dataset. The extensibility of the platform is demonstrated by adding a doublet-removal algorithm and recomputing the clustering of the cells. Any additional computational steps that take a cell-type expression counts matrix as input can be easily added to this framework with minimal effort. AvailabilityThe framework and its documentation for installation is available at the Github repository http://github.com/nj3252/CB-Source/ Contactkyun@houstonmethodist.org Supplementary informationSupplementary data available at Bioinformatics online.

bioinformatics↗

Causally Linking Neural Dominance to Perceptual Dominance in a Multisensory Conflict

When different senses are in conflict, one sense may dominate the perception of other sense, but it is not known whether the sensory cortex associated with the dominant modality exerts directional influence, at the functional brain level, over the sensory cortex associated with the dominated modality; in short, the link between sensory dominance and neuronal dominance is not established. In a task involving audio-visual conflict, using magnetoencephalography recordings in humans, we first demonstrated that the neuronal dominance - visual cortex being functionally influenced by the auditory cortex - was associated with the sensory dominance - participants visual perception being qualitatively altered by sound. Further, we found that prestimulus auditory-to-visual connectivity could predict the perceptual outcome on a trial-by-trial basis. Subsequently, we performed an effective connectivity-guided neurofeedback electroencephalography experiment and showed that participants who were briefly trained to increase the neuronal dominance from auditory to visual cortex also showed higher sensory, i.e. auditory, dominance during the conflict task immediately after the training. The results shed new light into the interactive neuronal nature of multisensory integration and open up exciting opportunities by enhancing or suppressing targeted mental functions subserved by effective connectivity.

neuroscience↗

The construction and application of a new 17-plex Y-STR system using universal fluorescent PCR

Y-chromosomal short tandem repeat (Y-STR) polymorphisms are useful in forensic identification, population genetics and human structures. However, the current Y-STR systems are limited in discriminating distant relatives in a family with a low discrimination power. Increasing the capacity of detecting Y chromosomal polymorphisms will drastically narrow down the matching number of genealogy populations or pedigrees. In this study, we developed a system containing 17 Y-STRs that are complementary to the current commercially available Y-STR kits. This system was constructed by multiplex PCR with expected sizes of 126-400 bp labeled by different fluorescence molecules (DYS715, DYS709, DYS716, DYS713 and DYS607 labeled by FAM; DYS718, DYS723, DYS708 and DYS714 labeled by JOE; DYS712, DYS717, DYS721 and DYS605 labeled by TAMRA; and DYS719, DYS726, DYS598 and DYS722 labeled by ROX). The system was extensively tested for sensitivity, male specificity, species specificity, mixture, population genetics and mutation rates following the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines. The genetic data were obtained from eight populations with a total of 1260 individuals. Our results showed that all the 17 Y-STRs are human- and male-specific and include only one copy of the Y-chromosome. The 17 Y-STR system detects 143 alleles and has a high discrimination power (0.996031746). Mutation rates were different among the 17 Y-STRs, ranging from 0.30% to 3.03%. In conclusion, our study provides a robust, sensitive and cost-effective genotyping method for human identification, which will be beneficial for narrowing the search scope when applied to genealogy searching with the Y-STR DNA databank.

genetics↗

Glioblastoma myeloid-derived suppressor cell subsets express differential macrophage migration inhibitory factor receptor profiles that can be targeted to reduce immune suppression

The application of tumor immunotherapy to glioblastoma (GBM) is limited by an unprecedented degree of immune suppression due to factors that include high numbers of immune suppressive myeloid cells, the blood brain barrier, and T cell sequestration to the bone marrow. We previously identified an increase in immune suppressive myeloid-derived suppressor cells (MDSCs) in GBM patients, which correlated with poor prognosis and was dependent on macrophage migration inhibitory factor (MIF). Here we examine the MIF signaling axis in detail in murine MDSC models, GBM-educated MDSCs and human GBM. We found that the monocytic subset of MDSCs (M-MDSCs), expressed high levels of the MIF cognate receptor CD74 and was localized in the tumor microenvironment. In contrast, granulocytic MDSCs (G-MDSCs) expressed high levels of the MIF non-cognate receptor CXCR2 and showed minimal accumulation in the tumor microenvironment. Furthermore, targeting M-MDSCs with ibudilast, a brain penetrant MIF-CD74 interaction inhibitor, reduced MDSC function and enhanced CD8 T cell activity in the tumor microenvironment. These findings demonstrate the MDSC subsets differentially express MIF receptors and may be leveraged for specific MDSC targeting.

immunology↗