Biology subjects

Du, W.

Publications and source records attributed to Du, W..

At least 37 records · Page 2Linked to original sources

bioRxiv2024

ERVcancer: a web resource designed for querying activation of human endogenous retroviruses across major cancer types

Human endogenous retroviruses (HERVs) compose approximately 8% of the human genome, co-opted into the dynamic regulatory network of cellular potency in early embryonic development. In recent studies, resurgent HERVs transcriptional activity has been frequently observed in many types of human cancers, suggesting their potential functions in the occurrence and progression of malignancy. However, a web resource dedicated to querying the relationship between activation of HERVs and cancer development is lacking. Here, we have constructed a database to explore the sequence information, expression profiles, survival prognosis, and genetic interactions of HERVs in diverse cancer types. Our database currently incorporates RNA sequencing (RNA-seq) data of 580 HERVs across 16246 samples, comprising 151 early embryonic data from the Gene Expression Omnibus (GEO) database, 8051 human adult tissues data from the Genotype-Tissue Expression (GTEx) project, 932 cancer cell lines data from the Cancer Cell Line Encyclopedia (CCLE) project, 6478 tumoral and 634 normal tissue samples data from The Cancer Genome Atlas (TCGA) project. The primary goal is to provide an easily accessible and user-friendly database for professionals in the fields of bioinformatics, pathology, pharmacology, and related areas, enabling them to efficiently screen the activity of HERVs of interest in normal and cancerous tissues and evaluate the clinical relevance. The ERVcancer database is available at http://kyuanlab.com/ervcancer/.

genomics↗

bioRxiv2024

High-motility pro-tumorigenic monocytes drive macrophage enrichment in the tumor microenvironment

Enrichment of tumor-associated macrophages (TAM{Phi}s) in the tumor microenvironment correlates with worse clinical outcomes in triple-negative breast cancer (TNBC) patients, prompting the development of therapies to inhibit TAM{Phi} infiltration. However, the lackluster efficacy of CCL2-based chemotaxis blockade in clinical trials suggests that a new understanding of monocyte/macrophage infiltration may be necessary. Here we demonstrate that random migration, and not only chemotaxis, drives macrophage tumor infiltration. We identified tumor- associated monocytes (TAMos) that display a dramatically enhanced migration capability, induced rapidly by the tumor microenvironment, that drives effective tumor infiltration, in contrast to low-motility differentiated macrophages. TAMo, not TAM{Phi}, promotes cancer cell proliferation through activation of the MAPK pathway. IL-6 secreted both by cancer cells and TAMo themselves enhances TAMo migration by increasing dendritic protrusion dynamics and myosin- based contractility via the JAK2/STAT3 signaling pathway. Independent from CCL2 mediated chemotaxis, IL-6 driven enhanced migration and pro-proliferative effect of TAMo were validated in a syngeneic TNBC mouse model. Depletion of IL-6 in cancer cells significantly attenuated monocyte infiltration and reversed TAMo-induced cancer cell proliferation. This work reveals the critical role random migration plays in monocyte driven TAM{Phi} enrichment in a tumor and pinpoints IL-6 as a potential therapeutic target in combination with CCL2 to ameliorate current strategies against TAM{Phi} infiltration.

immunology↗

bioRxiv2024

CLCC1 Governs Bilayer Equilibration at the Endoplasmic Reticulum to Maintain Cellular and Systemic Lipid Homeostasis

The intricate orchestration of lipid production, storage, and mobilization is vital for cellular and systemic homeostasis1,2. Dysfunctional plasma lipid control represents the major risk factor for cardio-metabolic diseases, the leading cause of human mortality3,4. Within the cellular landscape, the endoplasmic reticulum (ER) is the central hub of lipid synthesis and secretion, particularly in metabolically active hepatocytes in the liver or enterocytes in the gut5,6. Initially assembled in the ER lumen, lipid-ferrying lipoproteins necessitate the cross-membrane transfer of both neutral and phospho-lipids onto the lumenal apolipoprotein B (APOB), in a poorly-defined process7-10. Here we show that trans-bilayer equilibration of phospholipids, regulated by the ER protein CLCC1, determines lipid partition across the ER membrane and consequently systemic lipid homeostasis. CLCC1 partners with the phospholipid scramblase TMEM41B11,12 to recognize imbalanced bilayers and promote lipid scrambling, thereby licensing lipoprotein biogenesis and the subsequent bulk lipid transport. Strikingly, loss of CLCC1 or TMEM41B leads to the emergence of giant lumenal lipid droplets enclosed by extensively imbalanced ER bilayers, and consequently drastically accelerated pathogenesis of metabolic-dysfunction-associated liver steatohepatitis (MASH). The above results establish phospholipid scrambling at the ER as the lynchpin to maintain a dynamic equilibrium. Considering the requirement of trans-bilayer phospholipid equilibration in numerous biological processes, ranging from catabolic autophagy to viral infection13-16, our study may enable further elucidation of a previously under-appreciated homeostatic control mechanism intrinsic to the ER function in lipid biogenesis and distribution.

cell biology↗

bioRxiv2024

Stable and Oscillatory Hypoxia Differentially Regulate Invasibility of Breast Cancer Associated Fibroblasts

As local regions in the tumor outstrip their oxygen supply, hypoxia can develop, affecting not only the cancer cells, but also other cells in the microenvironment, including cancer associated fibroblasts (CAFs). Hypoxia is also not necessarily stable over time, and can fluctuate or oscillate. Hypoxia Inducible Factor-1 is the master regulator of cellular response to hypoxia, and can also exhibit oscillations in its activity. To understand how stable, and fluctuating hypoxia influence breast CAFs, we measured changes in gene expression in CAFs in normoxia, hypoxia, and oscillatory hypoxia, as well as measured change in their capacity to resist, or assist breast cancer invasion. We show that hypoxia has a profound effect on breast CAFs causing activation of key pathways associated with fibroblast activation, but reduce myofibroblast activation and traction force generation. We also found that oscillatory hypoxia, while expectedly resulted in a "sub-hypoxic" response in gene expression, it resulted in specific activation of pathways associated with actin polymerization and actomyosin maturation. Using traction force microscopy, and a nanopatterned stromal invasion assay, we show that oscillatory hypoxia increases contractile force generation vs stable hypoxia, and increases heterogeneity in force generation response, while also additively enhancing invasibility of CAFs to MDA-MB-231 invasion. Our data show that stable and unstable hypoxia can regulate many mechnobiological characteristics of CAFs, and can contribute to transformation of CAFs to assist cancer dissemination and onset of metastasis.

cancer biology↗

bioRxiv2024

A 3D in vitro assay to study combined immune cell infiltration and cytotoxicity

Immune cell-mediated killing of cancer cells in a solid tumor is prefaced by a multi-step infiltration cascade of invasion, directed migration, and cytotoxic activities. In particular, immune cells must invade and migrate through a series of different extracellular matrix (ECM) boundaries and domains before reaching and killing their target tumor cells. These infiltration events are a central challenge to the clinical success of CAR T cells against solid tumors. The current standard in vitro cell killing assays measure cell cytotoxicity in an obstacle-free, two-dimensional (2D) microenvironment, which precludes the study of 3D immune cell-ECM interactions. Here, we present a 3D combined infiltration/cytotoxicity assay based on an oil-in-water microtechnology. This assay measures stromal invasion following extravasation, migration through the stromal matrix, and invasion of the solid tumor in addition to cell killing. We compare this 3D cytotoxicity assay to the benchmark 2D assay through tumor assembloid cocultures with immune cells and engineered immune cells. This assay is amenable to an array of imaging techniques, which allows direct observation and quantification of each stage of infiltration in different immune and oncological contexts. We establish the 3D infiltration/cytotoxicity assay as an important tool for the mechanistic study of immune cell interactions with the tumor microenvironment. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=134 SRC="FIGDIR/small/586980v1_ufig1.gif" ALT="Figure 1"> View larger version (61K): org.highwire.dtl.DTLVardef@6a161dorg.highwire.dtl.DTLVardef@d1e5d3org.highwire.dtl.DTLVardef@47b87corg.highwire.dtl.DTLVardef@a0e051_HPS_FORMAT_FIGEXP M_FIG The 3D combined infiltration/cytotoxicity assay captures three important steps of immune cell infiltration into the solid tumor microenvironment: (1) circulating immune cells extravasate and invade the stromal matrix, (2) immune cells migrate through the stromal matrix to reach the tumor core, and (3) immune cells that successfully navigate the stroma must cross a basement membrane boundary secreted by the cancer cells to contact and kill the cancer cells within a solid tumor. C_FIG

cancer biology↗

bioRxiv2024

Gene editing of CD3 epsilon gene to redirect regulatory T cells for adoptive T cell transfer

I.Adoptive transfer of regulatory T cells (Tregs) is a promising strategy to combat immunopathologies in transplantation and autoimmune diseases. Antigen-specific Tregs are more effective in modulating undesired immune reactions, but their low frequency in peripheral blood poses challenges for manufacturing and their clinical application. Chimeric antigen receptors (CARs) have been used to redirect the specificity of Tregs, employing retroviral vectors. However, retroviral gene transfer is costly, time consuming, and raises safety issues. Here, we explored non-viral gene editing to redirect Tregs with CARs, using HLA-A2-specific constructs for proof-of-concept studies in transplantation models. We introduce a virus-free CRISPR-Cas12a approach to integrate an antigen-binding domain into the CD3 epsilon (CD3{varepsilon}) gene, generating Tregs expressing a T cell receptor fusion construct (TruC). These CD3{varepsilon}-TruC Tregs exhibit potent antigen-dependent activation while maintaining responsiveness to TCR/CD3 stimulation. This enables preferential enrichment of TruC-redirected Tregs via repetitive CD3/CD28-stimulation in a GMP-compatible expansion system. Non-viral gene edited CD3{varepsilon}-TruC Tregs retained their phenotypic, epigenetic, and functional identity. In a humanized mouse model, HLA-A2-specific CD3{varepsilon}-TruC Tregs demonstrate superior protection of allogeneic HLA-A2+ skin grafts from rejection compared to polyclonal Tregs. This approach provides a pathway for developing clinical-grade CD3{varepsilon}-TruC-based Treg cell products for transplantation immunotherapy and other immunopathologies.

immunology↗

bioRxiv2024

Oscillatory Hypoxia Induced Unfolded Protein Folding Response Gene Expression Predicts Low Survival in Human Breast Cancer Patients

Hypoxia is one of the key factors in the tumor microenvironment regulating nearly all steps in the metastatic cascade in many cancers, including in breast cancer. The hypoxic regions can however be dynamic with the availability of oxygen fluctuating or oscillating. The canonical response to hypoxia is relayed by transcription factor HIF-1, which is stabilized in hypoxia and acts as the master regulator of a large number of downstream genes. However, HIF-1 transcriptional activity can also fluctuate either due to unstable hypoxia, or by lactate mediated non-canonical degradation of HIF-1. Our understanding of how oscillatory hypoxia or HIF-1 activity specifically influence cancer malignancy is very limited. Here, using MDA-MB-231 cells as a model of triple negative breast cancer characterized by severe hypoxia, we measured the gene expression changes induced specifically by oscillatory hypoxia. We found that oscillatory hypoxia can specifically regulate gene expression differently, and at times opposite to stable hypoxia. Using The Cancer Genome Atlas (TCGA) RNAseq data of human cancer samples, we show that the oscillatory specific gene expression signature in MDA-MB-231 is enriched in most human cancers, and prognosticate low survival in breast cancer patients. In particular, we found that oscillatory hypoxia, unlike stable hypoxia, induces unfolded protein folding response (UPR) in cells resulting in gene expression predicting reduced survival.

cancer biology↗

bioRxiv2024

The J-Like Protein ARC6 Regulates Chloroplast FtsZ-Ring Assembly through Fine-tuning ARC3 Activity in Arabidopsis

Chloroplast division is initiated by the establishment of the stromal FtsZ ring (Z ring). Assembly and positioning of the Z ring are governed by the chloroplast Min system, which inhibits Z-ring formation everywhere but the middle of the chloroplast. ACCUMULATION AND REPLICATION OF CHLOROPLASTS3 (ARC3), the core component of this system, is a direct inhibitor of Z-ring assembly. Regulation of ARC3 activity is vital thus for chloroplast division. Here, we report that ARC6, which localizes on the chloroplast inner envelope membrane, interacts with ARC3 and acts upstream of ARC3 during chloroplast division. We show that the C-terminal MORN domain of ARC3, demonstrated previously to prevent ARC3-FtsZ interaction, binds to the J-like domain (JLD) of ARC6, enabling full-length ARC3 to interact with FtsZ proteins and activating the inhibitory activity of ARC3 on the assembly of FtsZ filaments. Overexpression of a JLD-deleted version of ARC6 causes disruption of Z-ring formation in an ARC3-dependent manner. Finally, we reveal that ARC6 recruits ARC3 to the middle of the chloroplast. Our findings suggest a model whereby ARC6 regulates the assembly and positioning of the Z ring through fine-tuning the inhibitory activity of ARC3 at the chloroplast division site. One Sentence SummaryThe chloroplast membrane protein ARC6 recruits ARC3 to the chloroplast division site and regulates the assembly of the FtsZ ring by fine-tuning ARC3 activity through its J-like domain. The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (https://academic.oup.com/plcell/pages/General-Instructions) is: Cheng Chen (cgchen@sjtu.edu.cn).

plant biology↗

bioRxiv2023

Engineering self-propelled tumor-infiltrating CAR T cells using synthetic velocity receptors

Chimeric antigen receptor (CAR) T cells express antigen-specific synthetic receptors, which upon binding to cancer cells, elicit T cell anti-tumor responses. CAR T cell therapy has enjoyed success in the clinic for hematological cancer indications, giving rise to decade-long remissions in some cases. However, CAR T therapy for patients with solid tumors has not seen similar success. Solid tumors constitute 90% of adult human cancers, representing an enormous unmet clinical need. Current approaches do not solve the central problem of limited ability of therapeutic cells to migrate through the stromal matrix. We discover that T cells at low and high density display low- and high-migration phenotypes, respectively. The highly migratory phenotype is mediated by a paracrine pathway from a group of self-produced cytokines that include IL5, TNF, IFN{gamma}, and IL8. We exploit this finding to "lock-in" a highly migratory phenotype by developing and expressing receptors, which we call velocity receptors (VRs). VRs target these cytokines and signal through these cytokines cognate receptors to increase T cell motility and infiltrate lung, ovarian, and pancreatic tumors in large numbers and at doses for which control CAR T cells remain confined to the tumor periphery. In contrast to CAR therapy alone, VR-CAR T cells significantly attenuate tumor growth and extend overall survival. This work suggests that approaches to the design of immune cell receptors that focus on migration signaling will help current and future CAR cellular therapies to infiltrate deep into solid tumors.

immunology↗

bioRxiv2023

Integration of ζ-deficient CARs into the CD3-zeta gene conveys potent cytotoxicity in T and NK cells

I.Chimeric antigen receptor (CAR)-reprogrammed immune cells hold significant therapeutic potential for oncology, autoimmune diseases, transplant medicine, and infections. All approved CAR-T therapies rely on personalized manufacturing using undirected viral gene transfer, which results in non-physiological regulation of CAR-signaling and limits their accessibility due to logistical challenges, high costs and biosafety requirements. Here, we propose a novel approach utilizing CRISPR-Cas gene editing to redirect T cells and natural killer (NK) cells with CARs. By transferring shorter, truncated CAR-transgenes lacking a main activation domain into the human CD3{zeta} (CD247) gene, functional CAR fusion-genes are generated that exploit the endogenous CD3{zeta} gene as the CARs activation domain. Repurposing this T/NK-cell lineage gene facilitated physiological regulation of CAR-expression and reprogramming of various immune cell types, including conventional T cells, TCR{gamma}/{delta} T cells, regulatory T cells, and NK cells. In T cells, CD3{zeta} in-frame fusion eliminated TCR surface expression, reducing the risk of graft-versus-host disease in allogeneic off-the-shelf settings. CD3{zeta}-CD19-CAR-T cells exhibited comparable leukemia control to T cell receptor alpha constant (TRAC)-replaced and lentivirus-transduced CAR-T cells in vivo. Tuning of CD3{zeta}-CAR-expression levels significantly improved the in vivo efficacy. Compared to TRAC-edited CAR-T cells, integration of a Her2-CAR into CD3{zeta} conveyed similar in vitro tumor lysis but reduced susceptibility to activation-induced cell death and differentiation, presumably due to lower CAR-expression levels. Notably, CD3{zeta} gene editing enabled reprogramming of NK cells without impairing their canonical functions. Thus, CD3{zeta} gene editing is a promising platform for the development of allogeneic off-the-shelf cell therapies using redirected killer lymphocytes. Key pointsO_LIIntegration of {zeta}-deficient CARs into CD3{zeta} gene allows generation of functional TCR-ablated CAR-T cells for allogeneic off-the-shelf use C_LIO_LICD3{zeta}-editing platform allows CAR reprogramming of NK cells without affecting their canonical functions C_LI

immunology↗

bioRxiv2023

Targeted genome editing restores auditory function in adult mice with progressive hearing loss caused by a human microRNA mutation

Mutations in microRNA-96 (MIR96) cause dominant delayed onset hearing loss DFNA50 without treatment. Genome editing has shown efficacy in hearing recovery by intervention in neonatal mice, yet editing in the adult inner ear is necessary for clinical applications. Here, we developed an editing therapy for a C>A point mutation in the seed region of the Mir96 gene, Mir9614C>A associated with hearing loss by screening gRNAs for genome editors and optimizing Cas9 and sgRNA scaffold for efficient and specific mutation editing in vitro. By AAV delivery in pre-symptomatic (3-week-old) and symptomatic (6-week-old) adult Mir9614C>A mutant mice, hair cell on-target editing significantly improved hearing long-term, with an efficacy inversely correlated with injection age. We achieved transient Cas9 expression without the evidence of AAV genomic integration to significantly reduce the safety concerns associated with editing. We developed an AAV-sgmiR96-master system capable of targeting all known human MIR96 mutations. As mouse and human MIR96 sequences share 100% homology, our approach and sgRNA selection for efficient and specific hair cell editing for long-term hearing recovery lays the foundation for future treatment of DFNA50 caused by MIR96 mutations.

bioengineering↗

bioRxiv2023

Matching or genetic engineering of HLA Class I and II facilitates successful allogeneic 'off-the-shelf' regulatory T cell therapy

The potential to harness regulatory T cells (Tregs) for the treatment of autoimmune diseases and transplant rejection has been restricted by several barriers: donor variability, manufacturing complications, and time-consuming expansion processes. These issues further complicate the use of autologous Tregs during acute disease phases or when Tregs are low in number or dysfunctional. Here we explore the potential of off-the-shelf allogeneic Tregs, from healthy donors or universal sources, to provide a more practical solution. We discover that the efficacy of these cells is undermined by the recipients immune response, and that that rigorous matching of HLA classes I and II overcomes this barrier. Importantly, genetically manipulating HLA expression enables the use of unmatched allogeneic Tregs with in vivo efficacy. Our findings underscore the transformative potential of HLA-engineered Tregs, offering a novel, ready-to-use therapeutic avenue for treating a wide array of inflammatory diseases. One-Sentence SummaryMatching or engineering of HLA-I and HLA-II facilitates allogeneic off-the-shelf regulatory T cells for immunoregulation.

immunology↗

bioRxiv2023

Mechano-induced homotypic patterned domain formation by monocytes

Matrix stiffness and corresponding mechano-signaling play indispensable roles in cellular phenotypes and functions. How tissue stiffness influences the behavior of monocytes, a major circulating leukocyte of the innate system, and how it may promote the emergence of collective cell behavior is less understood. Here, using tunable collagen-coated hydrogels of physiological stiffness, we show that human primary monocytes undergo a dynamic local phase separation to form highly patterned multicellular multi-layered domains on soft matrix. Local activation of the {beta}2 integrin initiates inter-cellular adhesion, while global soluble inhibitory factors maintain the steady-state domain pattern over days. Patterned domain formation generated by monocytes is unique among other key immune cells, including macrophages, B cells, T cells, and NK cells. While inhibiting their phagocytic capability, domain formation promotes monocytes survival. We develop a computational model based on the Cahn-Hilliard equation, which includes combined local activation and global inhibition mechanisms of intercellular adhesion suggested by our experiments, and provides experimentally validated predictions of the role of seeding density and both chemotactic and random cell migration on pattern formation.

biophysics↗

bioRxiv2023

Small extracellular vesicles promote stiffness-mediated metastasis

Tissue stiffness is a critical prognostic factor in breast cancer and is associated with metastatic progression. Here we show an alternative and complementary hypothesis of tumor progression whereby physiological matrix stiffness affects the quantity and protein cargo of small EVs produced by cancer cells, which in turn drive their metastasis. Primary patient breast tissue produces significantly more EVs from stiff tumor tissue than soft tumor adjacent tissue. EVs released by cancer cells on matrices that model human breast tumors (25 kPa; stiff EVs) feature increased adhesion molecule presentation (ITG2{beta}1, ITG6{beta}4, ITG6{beta}1, CD44) compared to EVs from softer normal tissue (0.5 kPa; soft EVs), which facilitates their binding to extracellular matrix (ECM) protein collagen IV, and a 3-fold increase in homing ability to distant organs in mice. In a zebrafish xenograft model, stiff EVs aid cancer cell dissemination through enhanced chemotaxis. Moreover, normal, resident lung fibroblasts treated with stiff and soft EVs change their gene expression profiles to adopt a cancer associated fibroblast (CAF) phenotype. These findings show that EV quantity, cargo, and function depend heavily on the mechanical properties of the extracellular microenvironment. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/545937v3_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@1be1dbdorg.highwire.dtl.DTLVardef@928710org.highwire.dtl.DTLVardef@1e14e9borg.highwire.dtl.DTLVardef@efdb7f_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2023

Tiny Earth CURE improves student persistence in science

Course-based undergraduate research experiences (CUREs) enhance student retention in STEM, particularly among students who belong to historically excluded communities. Yet the mechanisms by which CUREs contribute to student integration and persistence are poorly understood. Utilizing the Tripartite Integration Model of Social Influence (TIMSI), this longitudinal study examines how Tiny Earth, an antibiotic-discovery CURE, impacts students scientific self-efficacy, scientific identity, endorsement of scientific community values, and intentions to persist in science. The study also explores how gains in TIMSI factors vary as a function of student demographics and course characteristics. Results of pre-and post-course measurements show that scientific self-efficacy and identity increased among students in Tiny Earth, and some student demographics and course characteristics moderated these gains. Gains in scientific self-efficacy, identity, and values correlated with gains in persistence intentions, whereas student demographics and course characteristics did not. Results of this study show that the Tiny Earth CURE enhanced students integration into the scientific community, which was linked to intentions of students of both historically underrepresented and majority groups to persist in STEM. We discuss how courses that provide opportunity to learn science skills in the context of a CURE can contribute toward enlarging and diversifying the STEM workforce.

scientific communication and education↗

bioRxiv2023

Calorie Restriction activates a gastric Notch-FOXO1 pathway to expand Ghrelin cells

Calorie restriction increases lifespan. While some tissue-specific protective effects of calorie restriction have been described, the impact of calorie restriction on the gastrointestinal tract remains unclear. We found increased abundance of chromogranin A+, including orexigenic ghrelin+, endocrine cells in the stomach of calorie-restricted mice. This effect coincided with increased Notch target Hes1 and Notch ligand Jag1 and was reversed when Notch signaling was blocked using the {gamma}-secretase inhibitor DAPT. Using primary cultures and genetically-modified reporter mice, we determined that increased endocrine cell abundance was due to altered stem and progenitor proliferation. Different from the intestine, calorie restriction decreased gastric Lgr5+ stem cells, while increasing a FOXO1/Neurog3+ subpopulation of endocrine progenitors in a Notch-dependent manner. Further, calorie restriction triggered nuclear localization of FOXO1, which was sufficient to promote endocrine cell differentiation. Taken together, the data indicate that calorie restriction promotes gastric endocrine cell differentiation triggered by active Notch signaling and regulated by FOXO1.

cell biology↗

bioRxiv2023

Rescue of Auditory Function by a Single Administration of AAV-TMPRSS3 Gene Therapy in Aged Mice of Human Recessive Deafness DFNB8

AbstractsPatients with mutations in the TMPRSS3 gene suffer from recessive deafness DFNB8/DFNB10 for whom cochlear implantation is the only treatment option. Poor cochlear implantation outcomes are seen in some patients. To develop biological treatment for TMPRSS3 patients, we generated a knock-in mouse model with a frequent human DFNB8 TMPRSS3 mutation. The Tmprss3A306T/A306T homozygous mice display delayed onset progressive hearing loss similar to human DFNB8 patients. Using AAV2 as a vector to carry a human TMPRSS3 gene, AAV2-hTMPRSS3 injection in the adult knock-in mouse inner ears results in TMPRSS3 expression in the hair cells and the spiral ganglion neurons. A single AAV2-hTMPRSS3 injection in aged Tmprss3A306T/A306T mice leads to sustained rescue of the auditory function, to a level similar to the wildtype mice. AAV2-hTMPRSS3 delivery rescues the hair cells and the spiral ganglions. This is the first study to demonstrate successful gene therapy in an aged mouse model of human genetic deafness. This study lays the foundation to develop AAV2-hTMPRSS3 gene therapy to treat DFNB8 patients, as a standalone therapy or in combination with cochlear implantation.

neuroscience↗

bioRxiv2023

Analysis of donor pancreata defines the transcriptomic signature and microenvironment of early pre-neoplastic pancreatic lesions

The adult healthy human pancreas has been poorly studied given lack of indication to obtain tissue from the pancreas in the absence of disease and rapid postmortem degradation. We obtained pancreata from brain dead donors thus avoiding any warm ischemia time. The 30 donors were diverse in age and race and had no known pancreas disease. Histopathological analysis of the samples revealed PanIN lesions in most individuals irrespective of age. Using a combination of multiplex immunohistochemistry, single cell RNA sequencing, and spatial transcriptomics, we provide the first ever characterization of the unique microenvironment of the adult human pancreas and of sporadic PanIN lesions. We compared healthy pancreata to pancreatic cancer and peritumoral tissue and observed distinct transcriptomic signatures in fibroblasts, and, to a lesser extent, macrophages. PanIN epithelial cells from healthy pancreata were remarkably transcriptionally similar to cancer cells, suggesting that neoplastic pathways are initiated early in tumorigenesis. Statement of significanceThe causes underlying the onset of pancreatic cancer remain largely unknown, hampering early detection and prevention strategies. Here, we show that PanIN are abundant in healthy individuals and present at a much higher rate than the incidence of pancreatic cancer, setting the stage for efforts to elucidate the microenvironmental and cell intrinsic factors that restrain, or, conversely, promote, malignant progression.

cancer biology↗