Biology subjects

Boeing, S.

Publications and source records attributed to Boeing, S..

14 recordsLinked to original sources

bioRxiv2026

Targeting Myc activates a tissue-specific tumour resolution programme

Neoplastic transformation parallels hallmark cellular programs of tissue regeneration and wound repair1,2. However, the mechanisms driving tumour regression upon oncogenic driver inhibition--and why it often fails--remain poorly understood3-7. Oncogenic KRas mutations and Myc deregulation, two archetypal cancer drivers, frequently occur and cooperate to promote aggressive lung adenocarcinoma (LUAD)8-12. To investigate the mechanistic consequences of targeting Myc in LUAD, we applied spatiotemporally controlled genetic and functional perturbations in a reversible KRas/Myc-driven mouse model, integrated with RNA sequencing and immune protein profiling of tumours and their microenvironment. Acute oncogenic Myc inactivation in epithelial tumour cells elicits a localised regenerative immune response crucially dependent on rapid, transient release of the alarmin cytokine interleukin-33 (IL-33) by alveolar type 2 tumour cells. As a sentinel signal for Myc loss, IL-33 signalling reverses tumour immunosuppression and neoangiogenesis, critically recruits eosinophils, and promotes neoplastic cell elimination, driving regression beyond mere growth arrest. Notably, brief systemic recombinant IL-33 administration to mice with KRas/Myc-driven LUAD induces robust eosinophil influx and near-complete tumour resolution. Together, these findings demonstrate that blocking Myc activates an innate, tissue-intrinsic immune programme rooted in resolution of wound repair and capable of driving regression when activated in a tumour. This opens the possibility of treating cancer not only by blocking mitogenic oncogenic drivers but also by pro-actively triggering pro-resolution pathways.

cancer biology↗

bioRxiv2025

Splenic granulopoiesis and S100A9 drive resistance to checkpoint inhibitors conferred by liver metastases

Here, we investigate why liver metastases reduce the efficacy of immune checkpoint inhibitors (CPI). The poor prognosis of patients with liver metastases is associated with a systemic increase in neutrophils. Using experimental models, we confirm that mice with liver metastases respond poorly to CPI, have elevated neutrophils and suppress the response of subcutaneous lesions to CPI. We demonstrate that liver metastases, acting partly via IL-6, boost granulopoiesis in the spleen and promote the generation of immature S100A9hi neutrophils that suppress T-cell proliferation. Human liver metastases exhibit a similar increase in S100A9hi neutrophils. Neutrophil depletion attenuates the growth of liver metastases, but not subcutaneous metastases. Moreover, genetic deletion of S100A9 enables liver metastases to be effectively treated with CPI, and prevents liver metastases from suppressing the response in subcutaneous metastases. Thus, we document how liver metastases specifically change splenic granulopoiesis leading to changes in the microenvironment of non-hepatic lesions, and how targeting a key neutrophil protein restores the efficacy of CPI.

immunology↗

bioRxiv2025

TACI Regulates Marginal Zone B Cell Development

The mature B cell compartment consists of follicular (FO) and marginal zone (MZ) B cells, which develop from transitional type 2 (T2) B cells and mount T-dependent and T-independent antibody responses, respectively. TACI, a member of the TNF receptor superfamily, is expressed on all mature B cells, with highest levels on MZ B cells and plasma cells. Previous studies reported that TACI is a negative regulator of B cell survival. However, this conclusion is confounded by elevated levels of BAFF, a cytokine that supports B cell survival, in TACI- deficient mice. We now show that TACI does not directly regulate B cell survival but rather has a cell-intrinsic role in MZ B cell development. Loss of TACI leads to reduced MZ B cell numbers and impaired T-independent antibody responses. Mechanistically, we show that TACI is required for MZ B cell development from T2 B cell precursors via activation of the PI3K-AKT pathway and subsequent inhibition of the FOXO1 transcription factor.

immunology↗

bioRxiv2025

Anti-activin treatment increases T cell infiltration in breast and pancreatic tumours and promotes survival in a SMAD4-null mouse pancreatic cancer model

Activin A and B share the same downstream signalling pathway (activation of SMAD2/3) as TGF-{beta} and consequently elicit many of the same functional responses as TGF-{beta}, including immune suppression, activation of cancer-associated fibroblasts (CAFs) and extracellular matrix production and remodelling. However, activins role in tumourigenesis has been relatively overlooked compared to TGF-{beta}s. We generated and characterized a dual specificity human antibody that recognizes both activin A and B and compared its activity in syngeneic mouse models of breast cancer and pancreatic ductal adenocarcinoma (PDAC) with an activin A-specific antibody. We demonstrate that activin A and B are central to the function of CAFs and therapeutic inhibition of activin results in a reduction of collagen rich desmoplastic barriers, enabling the infiltration of cytotoxic T cells. This is correlated with an upregulation of the T cell chemoattractant CXCL10, which is normally repressed by activin signalling. Interestingly, despite greater T cell infiltration, activin A inhibition resulted in poorer survival in the KPC mouse model of PDAC and slightly larger tumours in the breast cancer model, indicating a tumour suppressive role of activin A-rich CAFs. Strikingly, however, treatment with the same anti-activin A antibody of PDAC tumours where SMAD4 is deleted in the tumour cells, resulted in increased survival, which was potentiated with additional treatment with immune checkpoint inhibitors. These results suggest that anti-activin therapy has potential for the cohort of PDAC patients exhibiting inactivation of SMAD4.

cancer biology↗

bioRxiv2025

The penetrant chordoid glioma PRKCA mutation is an oncogenic gain-of-function kinase inactivation eliciting early onset chondrosarcoma in mice.

The penetrant PRKCA D463H mutation, a biomarker and potential driver in chordoid glioma, was found to provoke the development of chondrosarcomas in heterozygous knock-in mice. This mutation entirely abrogates kinase activity, but strikingly no oncogenic phenotype is observed for the related inactivating mutation D463N indicating that the lack of activity is not the driver. In cells, the D463H mutant closely mirrored PKC WT behaviours and retained ATP binding, contrary to the related D463N mutant. Mechanistically, the PKC D463H mutant protein was found to display quantitative alterations to the PKC interactome, enhancing association with epigenetic regulators. This aligned with transcriptomic changes which resembled an augmented PKC expression program, with enhanced BRD4, Myc and TGF{beta} signatures. D463H dependent reduced sensitivity to the BET inhibitors JQ1 and AZD5153 indicates the functional importance of these pathways. The data show that D463H is a dominant gain-of-function oncogenic mutant, operating through a non-catalytic allosteric mechanism. One Sentence SummaryA PKC catalytic inactivating mutation confers gain-of-function properties - a paradigm shift in kinase actions.

cancer biology↗

bioRxiv2023

ARID3A coordinates the proliferation-differentiation switch of transit-amplifying cells in the intestine

Intestinal stem cells (ISCs) at the crypt base divide and give rise to progenitor cells that have the capacity to proliferate and differentiate into various mature epithelial cell types in the transit-amplifying (TA) zone. Here, we identified the transcription factor ARID3A as a novel regulator of intestinal epithelial cell proliferation and differentiation at the TA compartment. We show that ARID3A forms an expression gradient from villus tip to the early progenitors at the crypts mediated by TGF-{beta} and WNT signalling. Intestinal epithelial-specific deletion of Arid3a reduces proliferation of TA cells. Bulk and single cell transcriptomic analysis shows increased enterocyte differentiation and reduced secretory cells in the Arid3a cKO intestine. Interestingly, upper-villus gene signatures of both enterocytes and secretory cells are enriched in the mutant intestine. We find that the enhanced enterocyte differentiation in the Arid3a cKO intestine is caused by increased binding of HNF1 and HNF4. Finally, we show that loss of Arid3a impairs irradiation-induced regenerative process by altering the dynamics of proliferation and apoptosis. Our findings imply that ARID3A may play a gatekeeping role in the TA compartment to maintain the "just-right" proliferation-to-differentiation ratio for tissue homeostasis and plasticity.

developmental biology↗

bioRxiv2022

The identification of a gene expression signature of primordial follicle activation in mouse pregranulosa cells

Primordial follicles are quiescent ovarian structures comprised of a single oocyte surrounded by a layer of somatic supporting pregranulosa cells. Primordial follicle activation is the first step towards oocyte maturation and, ultimately, ovulation. As the number of quiescent primordial follicles is finite, their rate of activation is a critical parameter of the duration of the female reproductive lifespan. Activation status is established by the presence of cuboidal and proliferative granulosa cells in primary follicles, rather than squamous and quiescent pregranulosa cells in primordial follicles. Here, using a continuous Entropy Sort Feature Weighting approach on single-cell RNA sequencing data, we identify a distinct transcriptomic signature of activating pregranulosa cells in neonatal wildtype mice. This signature contains several genes previously linked with mature granulosa cells as well several novel candidates: Slc18a2, Tnni3, Fam13a and Myo1e. We confirm expression of Slc18a2 and TNNI3 in the granulosa cells of activating follicles in embryonic, neonatal and adult mouse ovaries. Perturbation of cell cycle inhibitor p27kip1 in Cdkn1b-/- mice results in complete activation of all primordial follicles during this neonatal period. Contrary to previous reports on this established mouse model, we find substantial transcriptomic changes in embryonic Cdkn1b-/- ovaries. Upon loss of cell-cycle inhibition, we find increased expression of our signature of pregranulosa cell activation, particularly that of cardiac troponin I (Tnni3). We conclude that pregranulosa cells engage a distinct transcriptional programme prior to cell-cycle dependent primordial follicle activation.

developmental biology↗

bioRxiv2022

Long-term retention of antigens in germinal centres is controlled by the spatial organisation of the follicular dendritic cell network

Germinal centers (GCs) require sustained availability of antigens to promote antibody affinity maturation against pathogens and vaccines. A key source of antigens for GC B cells are immune complexes (ICs) displayed on follicular dendritic cells (FDCs). Here we show that FDC spatial organization regulates antigen dynamics in the GC. We show the existence of two light zone (LZ) FDC populations, which differ in the duration of antigen retention. While the entire light zone (LZ) FDC network captures ICs initially, only the central cells of the network function as a long-term antigen reservoir, where different antigens arriving from subsequent immunizations co-localize. Mechanistically, central FDCs constitutively express subtly higher CR2 membrane densities than peripheral FDCs, which strongly increases the IC retention half-life. Even though repeated immunizations gradually saturate central FDCs, B cell responses remain efficient because new antigens partially displace old ones. These results reveal the principles shaping antigen display on FDCs during the GC reaction.

immunology↗

bioRxiv2022

A branching model of cell fate decisions in the enteric nervous system

How neurogenesis and gliogenesis are coordinated during development and why mature glial cells often share properties with neuroectodermal progenitors remains unclear. Here, we have used single cell RNA sequencing to map the regulatory landscape of neuronal and glial differentiation in the mammalian enteric nervous system (ENS). Our analysis indicates that neurogenic trajectories branch directly from a linear gliogenic axis defined by autonomic neural crest cells adopting sequential states as they progressively lose their strong neurogenic bias and acquire properties of adult enteric glia. We identify gene modules associated with transcriptional programs driving enteric neurogenesis and cell state transitions along the gliogenic axis. By comparing the chromatin accessibility profile of autonomic neural crest and adult enteric glia we provide evidence that the latter maintain an epigenetic memory of their neurogenic past. Finally, we demonstrate that adult enteric glia maintain neurogenic potential and are capable of generating enteric neurons in certain contexts by activating transcriptional programs employed by early ENS progenitors. Our studies uncover a novel configuration of enteric neurogenesis and gliogenesis that enables the coordinate development of ENS lineages and provides a mechanistic explanation for the ability of enteric glia to be functionally integrated into the adult intestine and simultaneously maintain attributes of early ENS progenitors.

neuroscience↗

bioRxiv2021

SIGNR1 promotes immune dysfunction in systemic candidiasis by modulating neutrophil lifespan via T cell-derived histones and G-CSF

The mechanisms regulating immune dysfunction during sepsis are poorly understood. Here, we show that neutrophil-derived myeloperoxidase delays the onset of immune dysfunction during systemic candidiasis by controlling microbes captured by splenic marginal zone (MZ) macrophages. In contrast, SIGNR1-mediated microbe capture accelerates MZ colonization and immune dysfunction by triggering T cell death, T cell-dependent chromatin release and the synergistic induction of G-CSF by histones and fungi. Histones and G-CSF promote the prevalence of immature Ly6Glow neutrophils with defective oxidative burst, by selectively shortening the lifespan of mature Ly6Ghigh neutrophils. Consistently, T cell deficiency, or blocking SIGNR1, G-CSF or histones delayed neutrophil dysfunction. Furthermore, histones and G-CSF in the plasma of sepsis patients, shortened neutrophil lifespan and correlated with neutrophil mortality markers associated with a poor prognosis. Hence, the compromise of internal antimicrobial barrier sites drives neutrophil dysfunction by selectively modulating neutrophil lifespan via pathogenic T cell death, extracellular histones, and G-CSF.

immunology↗

bioRxiv2020

KLF17 promotes human naïve pluripotency but is not required for its establishment

Current knowledge of the transcriptional regulation of human pluripotency is incomplete, with lack of inter-species conservation observed. Single-cell transcriptomics of human embryos previously enabled us to identify transcription factors, including the zinc-finger protein KLF17, that are enriched in the human epiblast and naive hESCs. Here we show that KLF17 is expressed coincident with the known pluripotency factors NANOG and SOX2 across human blastocyst development. We investigate the function of KLF17 in pluripotency using primed and naive hESCs for gain- and loss-of-function analyses. We find that ectopic expression of KLF17 in primed hESCs is sufficient to induce a naive-like transcriptome and that KLF17 can drive transgene-mediated resetting to naive pluripotency. This implies a role for KLF17 in establishing naive pluripotency. However, CRISPR-Cas9-mediated knockout studies reveal that KLF17 is not required for naive pluripotency acquisition in vitro. Transcriptome analysis of naive hESCs identifies subtle effects on metabolism and signalling following KLF17 loss of function, and possible redundancy with the related factor, KLF5. Overall, we show that KLF17 is sufficient, but not necessary, for naive pluripotency under the given in vitro conditions. Summary statementInvestigating KLF17 in human pluripotency reveals that it is sufficient, but not necessary, to establish naive hESCs. We posit that KLF17 is a peripheral regulator, like KLF2 in the mouse.

developmental biology↗

bioRxiv2020

Molecular characterization of projection neuron subtypes in the mouse olfactory bulb

Projection neurons (PNs) in the mammalian olfactory bulb (OB) receive direct input from the nose and project to diverse cortical and subcortical areas. Morphological and physiological studies have highlighted functional heterogeneity, yet no molecular markers have been described that delineate PN subtypes. Here, we used viral injections into olfactory cortex and fluorescent nucleus sorting to enrich PNs for high-throughput single nucleus and bulk RNA deep sequencing. Transcriptome analysis and RNA in situ hybridization identified three mitral and five tufted cell populations with characteristic transcription factor network topology and cell adhesion and excitability-related gene expression. Finally, by integrating bulk and snRNA-seq data we propose that different mitral cell populations selectively project to different regions of olfactory cortex. Together, we have identified potential molecular and gene regulatory mechanisms underlying PN diversity and provide new molecular entry points into studying the diverse functional roles of mitral and tufted cell subtypes.

neuroscience↗

bioRxiv2020

Enteric glia as a source of neural progenitors in adult zebrafish

The presence and identity of neural progenitors in the enteric nervous system (ENS) of vertebrates is a matter of intense debate. Here we demonstrate that the non-neuronal ENS cell compartment of teleosts shares molecular and morphological characteristics with mammalian enteric glia but cannot be identified by the expression of canonical glia markers. However, unlike their mammalian counterparts, which are generally quiescent and do not undergo neuronal differentiation during homeostasis, we show that a relatively high proportion of zebrafish enteric glia proliferate under physiological conditions giving rise to progeny that differentiate into enteric neurons. We also provide evidence that, similar to brain neural stem cells, the activation and neuronal differentiation of enteric glia are regulated by Notch signalling. Our experiments reveal remarkable similarities between enteric glia and brain neural stem cells in teleosts and open new possibilities for use of mammalian enteric glia as a potential source of neurons to restore the activity of intestinal neural circuits compromised by injury or disease.

neuroscience↗

bioRxiv2019

Neuronal programming by microbiota enables environmental regulation of intestinal motility

Environmental signals modulate the activity of the nervous system and harmonize its output with the outside world. Synaptic activity is crucial for integrating sensory and effector neural pathways but the role of transcriptional mechanisms as environmental sensors in the nervous system remains unclear. By combining a novel strategy for transcriptomic profiling of enteric neurons with microbiota manipulation, we demonstrate that the transcriptional programs of intestinal neural circuits depend on their anatomical and physiological context. We also identify the ligand-dependent transcription factor Aryl hydrocarbon Receptor (AhR) is an intrinsic regulator of enteric nervous system output. AhR is instated as a neuronal biosensor in response to microbiota colonization allowing resident enteric neurons to directly monitor and respond to the intestinal microenvironment. We suggest that AhR signaling integrates neuronal activity with host defence mechanisms towards gut homeostasis and health.\n\nOne Sentence SummaryMicrobiota induce expression of AhR in enteric neurons of the distal intestine enabling them to respond to environmental signals.

neuroscience↗