Biology subjects

Wang, A. Z.

Publications and source records attributed to Wang, A. Z..

12 recordsLinked to original sources

bioRxiv2026

Vault Packaging Dynamics: Cargo Loading Stabilizes MVP Conformation for High-Payload Cytokine Delivery in Cancer Therapy

Recombinant vaults are dynamic protein cages with a large interior volume that can encapsulate therapeutic cargo. Using integrative cryogenic electron microscopy (cryoEM), cryogenic electron tomography (cryoET) and charge-detection mass spectrometry (CDMS), we characterized recombinant empty and interleukin-2 (IL-2)-packaged human vaults produced in yeast to define assembly, packaging heterogeneity and conformational dynamics relevant to optimized cancer and immune therapeutics. CryoEM maps at 2.79 angstrom (packaged) and 3.16 angstrom (empty) reveal a D39-symmetric barrel built from 78 major vault protein (MVP) subunits each with an interaction domain (INT) that anchors a cargo on the inner surface at MVP repeats R3-R4. CDMS deconvolution of empty versus packaged particles yields two IL-2-INT vault populations centered near 100 and 400 molecules per vault, with a maximum of ~660 copies/vault (i.e., many more copies than the 78 available INT anchors), matching cryoET estimates of ~150-600. Both methods show that highly packaged vaults are enlarged and distorted. Empty particles are conformationally flexible, which promotes initial cargo entry; loading then stabilizes the barrel and condenses cargo, producing vaults that each contain many hundreds of IL-2 molecules. These data establish the structural basis of vault encapsulation and a quantitative framework for engineering vault-based delivery vehicles.

cell biology↗

bioRxiv2026

An Epigenetic Signature of Vulnerable Neurons is Under Selective Pressure Associated with Longevity Across Placental Mammals.

Age is the primary risk factor for neurodegenerative diseases, which are characterized by cell-type-specific vulnerability. Yet brain-aging mechanisms remain unclear given the complex, interacting age-associated pathways across diverse neural cell types. Here, we dissect cell type- cell state-specific aging gene regulatory programs and their contribution to cellular vulnerability by leveraging epigenomics, AI methodology, and natural lifespan diversity across placental mammals. Applying the TACIT method, we associated lifespans of 240 placental mammals to the predicted open chromatin levels of over 3 million orthologous loci across 18 cortical cell types. We identified thousands of lifespan-associated open chromatin regions, enriched near genes associated with hallmarks of aging, which stratified greatly by cell type. For example, regions near mitochondrial genes showed differential selective pressure in long-lived species in energetically-demanding layer V ET neurons, while regions near inflammatory response genes were under selective pressure in glial populations. We next asked whether regions linked to vulnerable or resilient neurons in the human brain were under differential selective pressure in longer lived species. Using an adaptive representation learning approach, we decompose intrinsic aging programs from systemic effects in the prefrontal cortex and define an aging signature predictive of cell-type-specific vulnerability. In Alzheimer's disease, this intrinsic aging signature more strongly predicts vulnerability than systemic effects. Active regions in vulnerable neurons showed lower predicted activity in species with longer lifespans, suggesting selective pressure to down-regulate the vulnerability-associated networks. Overall, our findings argue against a single master regulator of aging, instead implicating different hallmarks across different cell types.

genomics↗

bioRxiv2026

Integrated spatial and single-cell transcriptomic analysis of aggressive glioblastoma growth dynamics.

Glioblastoma (GBM) develops within a complex tumor ecosystem whose temporal dynamics remain poorly understood. Here, we performed longitudinal single-cell RNA sequencing and spatial transcriptomics across multiple timepoints in two widely used murine GBM models - CT2A and GL261 - which differ markedly in aggressiveness and response to immune checkpoint blockade. Tumor cell transcriptomes revealed model-specific programs: CT2A cells progressively upregulated epithelial-mesenchymal transition (EMT), non-classical MHC Class I, and progressively, hypoxia response pathways, resembling the human mesenchymal GBM cell state, while GL261 cells exhibited MHC Class II expression and developmental signatures resembling oligodendrocyte progenitor and astrocytic states. Ligand-receptor interaction analyses identified thrombospondins (Thbs1, Thbs2) and osteopontin (Spp1) as CT2A-specific tumor ligands mediating tumorigenic interactions with immune cells, with downstream targets enriched for EMT and TGF-{beta} pathways. Conversely, the GL261 model presented a differential potential to engage neuronal and perivascular guidance networks, with Glutamate and L1 cell adhesion molecule (L1cam) as lead signaling partners. The CT2A immune compartment exhibited progressive microglia-to-macrophage phenotypic conversion, enhanced macrophage infiltration driven by Spp1, and elevated T cell exhaustion, while GL261 maintained a distinct adaptive immune communication hub via MHC class II-CD4 signaling. Elevated THBS1, THBS2, and SPP1 expression correlated with poor survival in human GBM datasets. Together, these findings reveal divergent tumor-immune ecosystems in CT2A and GL261 that recapitulate distinct aspects of human GBM, with implications for therapeutic targeting.

cancer biology↗

bioRxiv2025

Histone methyltransferase DOT1L differentially affects the development of dendritic cell subsets

Dendritic cells (DCs) are important orchestrators of immune responses. Their development in the bone marrow is controlled by transcription factors, but epigenetic mechanisms remain poorly understood. DOT1L is emerging as a key epigenetic regulator in immune cells. By mapping DOT1L-mediated histone H3K79 methylation in canonical DC subsets, we observed that DOT1L modified common as well as DC subset-specific genes. In vitro- or in vivo-induced deletion of Dot1l followed by in vitro cell culture resulted in a decrease in myeloid progenitors and plasmacytoid DCs (pDCs) and an increase in cDC2s, while cDC1s remained unchanged. In vitro generated Dot1l-KO DCs were unable to produce IFN upon stimulation. Moreover, transcriptomes of Dot1l-KO DC subsets exhibited enrichment of antigen presentation pathways and MHC class II surface levels were upregulated in pDCs. Mechanistically, inhibition of DOT1L linked the observed effects to its methyltransferase activity. Together, our data indicate that in DCs DOT1L differentially affects the development of canonical subsets and suppresses antigen presentation pathways.

cell biology↗

bioRxiv2025

Single-Cell Analysis of Meningiomas Reveals Mutation-Associated Tumor and Immune Cell Gene Expression Programs

Genomic and epigenetic profiling, particularly DNA methylation analysis, have refined the molecular classification of meningiomas and revealed marked intratumoral heterogeneity. To further characterize heterogeneity within and between patients, we analyzed meningiomas using single-cell RNA sequencing (n=11), whole-exome sequencing (n=9), and spatial transcriptomics (n=3). Single-cell analysis revealed six transcriptionally distinct tumor cell states that corresponded to unique biological processes. Integration of the single-cell data with published exome and bulk RNA sequencing data from a large cohort revealed significant associations among somatic variants, tumor cell states, and immunological signatures. Notably, NF2-altered tumors were enriched for an epithelial-to-mesenchymal transition (EMT) cell state and immune cells, whereas NF2-intact tumors were enriched for a sterol metabolism cell state. Spatial transcriptomic analysis confirmed co-localization of immune cells and EMT tumor cells. Comparisons with immune cells from other brain tumors and peripheral tissues highlighted immunological cell states specific to meningioma. Collectively, these findings refine our genetic and molecular understanding of meningioma heterogeneity and underscore the link between genotype and molecular phenotype.

cancer biology↗

bioRxiv2025

Mapping the spatial architecture of glioblastoma from core to edge delineates niche-specific tumor cell states and intercellular interactions

Treatment resistance in glioblastoma (GBM) is largely driven by the extensive multi-level heterogeneity that typifies this disease. Despite significant progress toward elucidating GBMs genomic and transcriptional heterogeneity, a critical knowledge gap remains in defining this heterogeneity at the spatial level. To address this, we employed spatial transcriptomics to map the architecture of the GBM ecosystem. This revealed tumor cell states that are jointly defined by gene expression and spatial localization, and multicellular niches whose composition varies along the tumor core-edge axis. Ligand-receptor interaction analysis uncovered a complex network of intercellular communication, including niche- and region-specific interactions. Finally, we found that CD8 positive GZMK positive T cells colocalize with LYVE1 positive CD163 positive myeloid cells in vascular regions, suggesting a potential mechanism for immune evasion. These findings provide novel insights into the GBM tumor microenvironment, highlighting previously unrecognized patterns of spatial organization and intercellular interactions, and novel therapeutic avenues to disrupt tumor-promoting interactions and overcome immune resistance.

cancer biology↗

bioRxiv2024

Correspondence of fentanyl brain pharmacokinetics and behavior measured via engineering opioids biosensors and computational ethology

Despite the ongoing epidemic of opioid use disorder and death by fentanyl overdose, opioids remain the gold standard for analgesics. Pharmacokinetics (PK) dictates the individuals experience and utility of drugs; however, PK and behavioral outcomes have been conventionally studied in separate groups, even in preclinical models. To bridge this gap, we developed the first class of sensitive, selective, and genetically encodable fluorescent opioid biosensors, iOpioidSnFRs, including the fentanyl sensor, iFentanylSnFR. We expressed iFentanylSnFR in the ventral tegmental area of mice and recorded [fentanyl] alongside videos of behaviors before and after administration. We developed a machine vision routine to quantify the effects of the behavior on locomotor activity. We found that mice receiving fentanyl exhibited a repetitive locomotor pattern that paralleled the [fentanyl] time course. In a separate experiment, mice navigating a complex maze for water showed a dose-dependent impairment in navigation, in which animals repeated incorrect paths to the exclusion of most of the unexplored maze for the duration of the average fentanyl time course. This approach complements classical operant conditioning experiments and introduces a key feature of human addiction, the ability to carry out an ethologically relevant survival task, only now quantified in rodents. Finally, we demonstrate the utility of iFentanylSnFR in detecting fentanyl spiked into human biofluids and the generalizability of engineering methods to evolve selective biosensors of other opioids, such as tapentadol and levorphanol. These results encourage diagnostic and continuous monitoring approaches to personalizing opioid regimens for humans.

neuroscience↗

bioRxiv2023

Glioblastoma-infiltrating CD8+ T cells are predominantly a clonally expanded GZMK+ effector population

Recent clinical trials have highlighted the limited efficacy of T cell-based immunotherapy in patients with glioblastoma (GBM). To better understand the characteristics of tumor-infiltrating lymphocytes (TIL) in GBM, we performed cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) and single-cell RNA sequencing (scRNA-seq) with paired V(D)J sequencing, respectively, on TIL from two cohorts of patients totaling 15 patients with high grade glioma, including GBM or astrocytoma, IDH mutant, grade 4 (G4A). Analysis of the CD8+ TIL landscape reveals an enrichment of clonally expanded GZMK+ effector T cells in the tumor compared to matched blood, which was validated at the protein level. Furthermore, integration with other cancer types highlights the lack of a canonically exhausted CD8+ T cell population in GBM TIL. These data suggest that GZMK+ effector T cells represent an important T cell subset within the GBM microenvironment and which may harbor potential therapeutic implications. SignificanceIn order to understand the limited efficacy of immune checkpoint blockade in GBM, we endeavor to understand the TIL landscape through a multi-omics approach. In this study, by highlighting the enrichment of GZMK+ effector T cells and lack of exhausted T cells, we provide a new potential mechanism of resistance to immunotherapy in GBM.

immunology↗

bioRxiv2021

The conventional dendritic cell 1 subset primes CD8+ T cells and traffics tumor antigen to drive anti-tumor immunity in the brain

The central nervous system (CNS) antigen presenting cell (APC) which primes anti-tumor CD8+ T cell responses remains undefined. Elsewhere, the conventional dendritic cell 1 (cDC1) performs this role. However, steady-state brain cDC1 are rare; cDC localize to choroid plexus and dura. Using preclinical glioblastoma models and cDC1-deficient mice, we explored the role of cDC1 in CNS anti-tumor immunity. We determined that cDC1 mediate checkpoint blockade-induced survival benefit and prime neoantigen-specific CD8+ T cells against brain tumors. We observed that cDC, including cDC1, isolated from the tumor, the dura, and the CNS-draining cervical lymph nodes harbored a traceable fluorescent tumor-antigen. In patient samples, we observed several APC subsets (including the CD141+ cDC1-equivalent) infiltrating glioblastomas, meningiomas, and dura. In these same subsets, we identified a tumor-specific fluorescent metabolite of 5- aminolevulinic acid, which labels tumor cells during fluorescence-guided glioblastoma resection. Together, these data elucidate the specialized behavior of cDC1 and suggest cDC1 play a significant role in CNS anti-tumor immunity. One Sentence SummaryCNS cDC1 engage in previously undefined behavior to establish immune responses against brain tumors.

immunology↗

bioRxiv2021

Single Cell Atlas of Human Dura Reveals Cellular Meningeal Landscape and Insights into Meningioma Immune Response

Recent investigation of the meninges, specifically the dura layer, has highlighted its importance in CNS immune surveillance beyond a purely structural role. However, most of our understanding of the meninges stems from the use of pre-clinical models rather than human samples. In this study, we use single cell RNA-sequencing to perform the first characterization of both non-tumor-associated human dura and meningioma samples. First, we reveal a complex immune microenvironment in human dura that is transcriptionally distinct from that of meningioma. In addition, through T cell receptor sequencing, we show significant TCR overlap between matched dura and meningioma samples. We also identify a functionally heterogeneous population of non-immune cell types and report copy-number variant heterogeneity within our meningioma samples. Our comprehensive investigation of both the immune and non-immune cell landscapes of human dura and meningioma at a single cell resolution provide new insight into previously uncharacterized roles of human dura.

immunology↗

bioRxiv2021

DUSP6 mediates resistance to JAK2 inhibition and drives leukemic progression

Chronic myeloproliferative neoplasms (MPNs) exhibit a propensity for transformation to secondary acute myeloid leukemia (sAML), for which the underlying mechanisms remain poorly understood, resulting in limited treatment options and dismal clinical outcomes. Here, we performed bulk transcriptome profiling accompanied by single cell RNA-sequencing on CD34+ stem/progenitor cells from serial patient samples obtained at the chronic MPN and sAML phases, and identified aberrantly increased expression of dual-specificity phosphatase 6 (DUSP6) underlying disease transformation. Genetic and pharmacologic targeting of DUSP6 led to inhibition of S6 and JAK/STAT signaling, resulting in potent suppression of cell proliferation, while also reducing inflammatory cytokine production in primary samples. Furthermore, ectopic DUSP6 expression augmented proliferation and mediated JAK2 inhibitor resistance, while DUSP6 inhibition reduced colony-forming potential of JAK2 inhibitor-persistent patient cells. Mechanistically, DUSP6 perturbation dampened S6 signaling via inhibition of RSK1, which we identified as a second indispensable candidate associated with poor clinical outcome. Lastly, DUSP6 inhibition potently suppressed disease development across Jak2 V617F and MPL W515L MPN mouse models, and sAML patient-derived xenografts. These findings underscore DUSP6 in driving disease transformation and therapeutic resistance, and highlight the DUSP6-RSK1 axis as a novel, druggable pathway in myeloid malignancies.

cancer biology↗

bioRxiv2019

Prostate-Specific Antigen Dynamics Predict Individual Responses to Intermittent Androgen Deprivation

BackgroundIntermittent androgen deprivation therapy (IADT) is an attractive treatment approach for biochemically recurrent prostate cancer (PCa), whereby cycling treatment on and off can reduce cumulative dose, limit toxicities, and delay development of treatment resistance. To optimize treatment within the context of ongoing intratumoral evolution, underlying mechanisms of resistance and actionable biomarkers need to be identified.\n\nMethodsWe have developed a quantitative framework to simulate enrichment of prostate cancer stem cell (PCaSC) dynamics during treatment as a plausible mechanism of resistance evolution.\n\nResultsSimulated dynamics of PCaSC and non-stem cancer cells demonstrate that stem cell proliferation patterns correlate with longitudinal serum prostate-specific antigen (PSA) measurements in 70 PCa patients undergoing multiple cycles of IADT. By learning the dynamics from each treatment cycle, individual model simulations predict evolution of resistance in the subsequent IADT cycle with a sensitivity and specificity of 57% and 94%, respectively and an overall accuracy of 90%. Additionally, we evaluated the potential benefit of docetaxel for IADT in biochemically recurrent PCa. Model simulations based on response dynamics from the first IADT cycle identify patients who would or would not benefit from concurrent docetaxel in subsequent cycles.\n\nConclusionOur results demonstrate the feasibility and potential value of adaptive clinical trials guided by patient-specific mathematical models of intratumoral evolutionary dynamics continuously updated with each treatment cycle.\n\nTranslational RelevanceCompared to continuous androgen deprivation therapy, intermittent androgen deprivation (IADT) has been shown to reduce toxicity and delay time to progression in prostate cancer. While numerous mathematical models have been developed to study the response to both continuous and intermittent androgen deprivation, very few have identified actionable biomarkers of resistance and exploited them to predict how patients will or will not respond to subsequent treatment. Here, we identify prostate-specific antigen (PSA) dynamics as the first such biomarker. Mechanistic mathematical modeling of prostate cancer stem cell dynamics that dictate prostate-specific antigen serum levels predicts individual responses to IADT with 90% overall accuracy and can be used to develop patient-specific adaptive treatment protocols, and potentially identify patients that may benefit from concurrent chemotherapy. Model results demonstrate the feasibility and potential value of adaptive clinical trials guided by patient-specific mathematical models of intratumoral evolutionary dynamics continuously updated with each treatment cycle.

cancer biology↗