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Duong, E.

Publications and source records attributed to Duong, E..

5 recordsLinked to original sources

The CD8 immgenT framework as a universal reference of mouse CD8 Tαβ cell differentiation states

Mouse CD8+ T cell differentiation has been studied extensively in models of infections and tumors, yet no unified framework spans the full spectrum of immunological contexts. Within the immgenT project, we profiled RNA, surface markers, and TCR clonotypes in conventional CD8+ T cells across >600 samples, spanning multiple perturbations, tissues, and timepoints. Twenty-one clusters across naive, effector, circulating memory, tissue-resident memory, progenitor-exhausted, and terminally-exhausted CD8+ T cell compartments emerged, with striking molecular convergence across acute and chronic infections, tumors, autoimmunity, aging, and homeostasis, illustrating that shared transcriptional states support protective or dysfunctional outcomes depending on developmental history and microenvironment. We validate immgenT as a comprehensive reference by integrating external datasets from conditions not represented in immgenT and by defining a flow cytometry panel spanning the CD8+ T cell landscape. Thus, immgenT-CD8 provides a molecular framework for harmonizing CD8+ T cell literature and clarifies relationships across diverse immune challenges.

immunology↗

AAV Kills Dividing Cells by Depleting PARP1 and Other DNA Damage Response Proteins

Recombinant adeno-associated virus (rAAV) is a replication-defective viral vector used in hundreds of human gene therapy trials, resulting in five FDA-approved therapies. Despite this success, rAAV-based gene therapies suffer from dose-limiting toxicities, resulting in several severe adverse reactions, including death. Previously, we discovered that rAAV rapidly kills mouse NPCs in vitro and in vivo. This vector contains a minimal genome comprised of 145-base pair inverted terminal repeats (ITRs) with a T-shaped hairpin structure that appears to be necessary and sufficient for this toxicity. However, the mechanism for AAV ITR toxicity is not known, and there have been few attempts to engineer ITRs to attenuate rAAV toxicity. In the current study, we explore the molecular mechanisms that drive dose-dependent rAAV toxicity in dividing human NPCs (hNPCs) and test whether disrupting these mechanisms mitigates this toxicity. Recombinant AAV infection induces aberrant cell cycle progression with activation of the ATM /CHK1/CHK2 pathway and expression of the DNA damage markers {gamma}H2AX and 53BP1. Affinity-based proteomics indicate that AAV ITRs bind to Poly-(ADP-Ribose)polymerase 1 (PARP1) and other DNA damage response (DDR) proteins involved in single-strand break repair (SSBR). Recombinant AAV infection attenuates poly-(ADP-ribose) (PAR) formation and mimics the antiproliferative effects of pharmacological PARP inhibitors used in cancer therapy. Moreover, treatment of hNPCs with PARP inhibitors is sufficient to reproduce many features of rAAV-induced toxicity. Finally, we demonstrate that eliminating the T-shaped hairpin within the AAV ITR reduces binding to SSBR proteins and the resulting rAAV toxicity. These findings suggest that rAAV infection induces replication stress and cell death in dividing hNPCs by functionally depleting PARP1 and other DDR proteins that are essential for DNA replication. This work fills substantial gaps in the understanding of the mechanisms of rAAV toxicity and has important implications for the development of safer rAAV-based human gene therapies. One Sentence SummaryThe rAAV genome binds to and depletes PARP1 and other SSBR proteins that are essential for DNA replication, resulting in DNA double stranded breaks, checkpoint activation, and cell death in dividing cells.

cell biology↗

A single MHCII neoepitope mRNA vaccine elicits CD4 T- and B- cell responses promoting endogenous CD8 anti-tumor immunity

Recent progress in therapeutic cancer vaccines has shown promising clinical activity, especially when targeting MHC class I (MHCI) neoantigen-specific CD8+ T cell responses in post-surgical patients. To explore the role of CD4+ T cells in vaccine-dependent tumor rejection, we constructed an mRNA lipoplex vaccine encoding a single MHCII-restricted neoantigen. The vaccine elicited Tfh and Th1 cell responses while decreasing Tregs, leading to rejection of established tumors in mice. IL-21 and IFN-{gamma}, crucial for Tfh and Th1 function respectively, contributed to anti-tumor activity. B cells and neoantigen-specific antibodies were also shown to participate in vaccine efficacy. Additionally, conventional type 1 dendritic cells (cDC1s) were essential for eliciting vaccine-induced CD4+ T cells, and both cDC1s and CD4+ T cells were required to enhance endogenous CD8+ responses, which were crucial for tumor control. Our results suggest that immunizing against MHCII neoantigens alone is sufficient to orchestrate a potent and cooperative immune response against cancer.

immunology↗

Intratumoral cDC1-T Cell Clusters Serve as Sites of Local Costimulation to Enhance CTL-Mediated Tumor Rejection

T cells are essential for anti-tumor immunity, but their ability to eliminate tumors depends on coordinated interactions with type 1 conventional dendritic cells (cDC1s). While cDC1s are known for cross-presenting tumor-derived antigens in lymph nodes to prime CD8+ T cells, their role within the tumor itself remains less well understood. Here, we use the Skin Tumor Array by Micro-Poration (STAMP) model to investigate how cDC1-T cell interactions shape immune responses and influence tumor fate. Our data reveal that it is the spatial distribution of both cDC1s and T cells that determines whether a tumor can be rejected. We defined three primary immunotypes based on the spatial distribution of T cells and cDC1s: T cell-inflamed/dendritic cell-inflamed (TC-In/DC-In) tumors, where T cells and cDC1s co-infiltrate the tumor; T cell-inflamed/dendritic cell-excluded (TC-In/DC-Ex) tumors, where T cells infiltrate but cDC1s remain at the periphery; and T cell-excluded/dendritic cell-excluded (TC-Ex/DC-Ex) tumors, which lack both cDC1 and T cell infiltration. Notably, TC-In/DC-In tumors are more likely to undergo rejection, whereas TC-In/DC-Ex tumors persist despite T cell infiltration. Within TC-In/DC-In tumors, cDC1s engage in direct interactions with T cells, upregulate co-stimulatory molecules, and sustain effector T cell responses, while cDC1s in TC-In/DC-Ex tumors express higher migration-associated genes, suggesting a propensity to exit the tumor. We further show that chemokine modulation, particularly through CXCL9, CCL5, and XCL1, can reshape immune infiltration patterns to promote intra-tumoral cDC1-T cell clustering and improve tumor rejection. These findings underscore the unexpectedly important role of cDC1 positioning and function in sustaining effective anti-tumor immunity and highlight spatially organized cDC1-T cell clusters as critical hubs for local T cell activation.

immunology↗

Lung cancer-intrinsic SOX2 expression mediates resistance to checkpoint blockade therapy by inducing Treg-dependent CD8+ T cell exclusion

Tumor-intrinsic signaling pathways can drastically affect the tumor immune microenvironment (TME), promoting tumor progression and resistance to immunotherapy by excluding immune cell populations from the tumor. Several tumor-cell intrinsic pathways have been reported to affect myeloid cell infiltration and downstream T cell infiltration. Clinical evidence suggests that the exclusion of cytotoxic T cells from the tumor core likewise mediates resistance. Here, we find that tumor cell-intrinsic SOX2 expression induces the exclusion of cytotoxic T cells from the tumor core and promotes resistance to checkpoint blockade therapy. CD8+ T cell exclusion was dependent on regulatory T cell-mediated suppression of tumor vasculature. Depleting tumor-infiltrating regulatory T cells via Glucocorticoid-Induced TNFR-Related (GITR) restored CD8+ T cell infiltration and reduced tumor growth in combination with checkpoint blockade therapy. SignificanceWe identified tumor cell-intrinsic SOX2 expression in lung cancer as a mechanism of resistance to immunotherapy. SOX2 expression increases regulatory T cell populations in the TME, negatively affecting the tumor vasculature and blunting CD8+ T cell infiltration into the tumor core. This effect could be reverted by targeting regulatory T cells with anti-GITR therapy.

immunology↗