D. A. Ingram et al. (Apr 2025)
Nature Communications 16
GRAMD1B is a regulator of lipid homeostasis, autophagic flux and phosphorylated tau
Lipid dyshomeostasis and tau pathology are present in frontotemporal lobar degeneration (FTLD) and Alzheimer’s disease (AD). However,the relationship between lipid dyshomeostasis and tau pathology remains unclear. We report that GRAM Domain Containing 1B (GRAMD1B),a nonvesicular cholesterol transporter,is increased in excitatory neurons of human neural organoids (HNOs) with the MAPT R406W mutation. Human FTLD,AD cases,and PS19 tau mice also have increased GRAMD1B expression. We show that overexpression of GRAMD1B increases levels of free cholesterol,lipid droplets,and impairs autophagy flux. Modulating GRAMD1B in iPSC-derived neurons also alters key autophagy-related components such as PI3K,phospho-AKT,and p62,as well as phosphorylated tau,and CDK5R1. Blocking GRAMD1B function decreases free cholesterol and lipid droplets. Knocking down GRAMD1B additionally reduces phosphorylated tau,and CDK5R1 expression. Our findings elucidate the role of GRAMD1B in the nervous system and highlight its relevance to FTLD and AD. Subject terms: Diseases of the nervous system,Ageing
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H. Xu et al. (Apr 2025)
Cancer Cell International 25 20
Single-cell transcriptome sequencing reveals the mechanism of Realgar improvement on erythropoiesis in mice with myelodysplastic syndrome
Myelodysplastic syndrome (MDS) is a malignant hematologic disorder with limited curative options,primarily reliant on hematopoietic stem cell transplantation. Anemia,a prevalent symptom of MDS,has few effective treatment strategies. Realgar,though known for its therapeutic effects on MDS,remains poorly understood in terms of its mechanism of action. In this study,both in vivo and in vitro experiments were conducted using Realgar and its primary active component,As 2 S 2,to examine their impact on mouse erythroblasts at the single-cell level. Realgar treatment significantly altered the transcriptional profiles and cellular composition of bone marrow in mice,both in vivo and in vitro. Differentially expressed genes in erythroblasts regulated by Realgar were identified,unveiling potential regulatory functions and signaling pathways,such as heme biosynthesis,hemoglobin production,oxygen binding,IL-17 signaling,and MAPK pathways. These findings suggest that Realgar enhances the differentiation of erythroblasts in mouse bone marrow and improves overall blood cell counts. This work offers preliminary insights into Realgar’s mechanisms,expands the understanding of this mineral medicine,and may inform strategies to optimize its therapeutic potential in hematologic diseases. The online version contains supplementary material available at 10.1186/s12935-025-03768-0.
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D. Reginensi et al. (Apr 2025)
Scientific Reports 15
Region-specific brain decellularized extracellular matrix promotes cell recovery in an in vitro model of stroke
Brain decellularized extracellular matrix (ECM) can be an attractive scaffold capable of mimicking the native ecosystem of the central nervous system tissue. We studied the in vitro response of neural cultures exposed to region-specific brain decellularized ECM scaffolds from three distinct neuroanatomical sections: cortex,cerebellum and remaining areas. First,each brain region was evaluated with the isotropic fractionator method to understand the cellular composition of the different cerebral areas. Second,the cerebral regions were subjected to the decellularization process and their respective characterization using molecular,histological,and ultrastructural techniques. Third,the levels of neurotrophic factors in the decellularized brain scaffold were analyzed. Fourth,we studied the region-specific brain decellularized ECM as a mimetic platform for the maturation of PC12 cells,as a unidirectional model of differentiation. Finally,in vitro studies were carried out to evaluate the cell recovery capacity of brain decellularized ECM under stroke-mimetic conditions. Our results show that region-specific brain decellularized ECM can serve as a biomimetic scaffold capable of promoting the growth of neural lineage cells and,in addition,it possesses a combination of structural and biochemical signals (e.g.,neurotrophic factors) that are capable of inducing cell phenotypic changes and promote viability and cell recovery in a stroke/ischemia model in vitro. The online version contains supplementary material available at 10.1038/s41598-025-95656-w.
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R. Dalangin et al. (Apr 2025)
Nature Communications 16
Far-red fluorescent genetically encoded calcium ion indicators
Genetically encoded calcium ion (Ca 2+ ) indicators (GECIs) are widely-used molecular tools for functional imaging of Ca 2+ dynamics and neuronal activities with single-cell resolution. Here we report the design and development of two far-red fluorescent GECIs,FR-GECO1a and FR-GECO1c,based on the monomeric far-red fluorescent proteins mKelly1 and mKelly2. FR-GECOs have excitation and emission maxima at ~596 nm and ~644 nm,respectively,display large responses to Ca 2+ in vitro (Δ F / F 0 = 6 for FR-GECO1a,18 for FR-GECO1c),are bright under both one-photon and two-photon illumination,and have high affinities (apparent K d = 29 nM for FR-GECO1a,83 nM for FR-GECO1c) for Ca 2+ . FR-GECOs offer sensitive and fast detection of single action potentials in neurons,and enable in vivo all-optical manipulation and measurement of cellular activities in combination with optogenetic actuators. Subject terms: Fluorescent proteins,Optogenetics,Zebrafish,Molecular neuroscience,Calcium signalling
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J. H. Hammel et al. (Apr 2025)
APL Bioengineering 9 2
Interstitial fluid flow in an engineered human lymph node stroma model modulates T cell egress and stromal change
The lymph node (LN) performs essential roles in immunosurveillance throughout the body. Developing in vitro models of this key tissue is of great importance to enhancing physiological relevance in immunoengineering. The LN consists of stromal populations and immune cells,which are highly organized and bathed in constant interstitial fluid flow (IFF). The stroma,notably the fibroblastic reticular cells (FRCs) and the lymphatic endothelial cells (LECs),play crucial roles in guiding T cell migration and are known to be sensitive to fluid flow. During inflammation,interstitial fluid flow rates drastically increase in the LN. It is unknown how these altered flow rates impact crosstalk and cell behavior in the LN,and most existing in vitro models focus on the interactions between T cells,B cells,and dendritic cells rather than with the stroma. To address this gap,we developed a human engineered model of the LN stroma consisting of FRC-laden hydrogel above a monolayer of LECs in a tissue culture insert with gravity-driven interstitial flow. We found that FRCs had enhanced coverage and proliferation in response to high flow rates,while LECs experienced decreased barrier integrity. We added CD4+ and CD8+ T cells and found that their egress was significantly decreased in the presence of interstitial flow,regardless of magnitude. Interestingly,3.0 μ m/s flow,but not 0.8 μ m/s flow,correlated with enhanced inflammatory cytokine secretion in the LN stroma. Overall,we demonstrate that interstitial flow is an essential consideration in the lymph node for modulating LN stroma morphology,T cell migration,and inflammation.
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A. Wiegering et al. (Apr 2025)
Nature Communications 16
A differential requirement for ciliary transition zone proteins in human and mouse neural progenitor fate specification
Studying ciliary genes in the context of the human central nervous system is crucial for understanding the underlying causes of neurodevelopmental ciliopathies. Here,we use pluripotent stem cell-derived spinal organoids to reveal distinct functions of the ciliopathy gene RPGRIP1L in humans and mice,and uncover an unexplored role for cilia in human axial patterning. Previous research has emphasized Rpgrip1l critical functions in mouse brain and spinal cord development through the regulation of SHH/GLI pathway. Here,we show that RPGRIP1L is not required for SHH activation or motoneuron lineage commitment in human spinal progenitors and that this feature is shared by another ciliopathy gene,TMEM67 . Furthermore,human RPGRIP1L -mutant motoneurons adopt hindbrain and cervical identities instead of caudal brachial identity. Temporal transcriptome analysis reveals that this antero-posterior patterning defect originates in early axial progenitors and correlates with cilia loss. These findings provide important insights into the role of cilia in human neural development. Subject terms: Ciliogenesis,Pattern formation,Pluripotent stem cells,Neurogenesis
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T. Zhang et al. (Apr 2025)
Cancer Cell International 25 6
Heme oxygenase 1 confers gilteritinib resistance in FLT3-ITD acute myeloid leukemia in a STAT6-dependent manner
Acute myeloid leukemia (AML) is the most common type of acute leukemia in adults. We previously discovered that heme oxygenase 1 (HO1) is crucial for chemoresistance in AML,but the detailed molecular mechanism of that remains unclear. RNA sequencing was conducted to assess transcriptomic changes in three pairs of AML cells after regulating the expression of HO1. The molecular mechanism by which HO1 induces gilteritinib resistance in FLT3-ITD (FMS-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD)) AML was evaluated by quantitative real-time PCR (qRT-PCR),CCK-8,flow cytometry,and western blotting. FLT3-ITD AML mouse models were established to investigate the effects of HO1 expression on gilteritinib resistance in vivo. In these three pairs of AML cells,we discovered that HO1-mediated drug resistance is connected to the interleukin-4-mediated signaling pathway (specifically STAT6) only in MV4-11 cells with the FLT3-ITD mutation. Further findings revealed that HO1 overexpression confers gilteritinib resistance in FLT3-ITD AML cell lines and primary individual specimens. While suppression of HO1 sensitized FLT3-ITD AML cell lines and primary individual specimens to gilteritinib. Mechanistically,western blotting and flow cytometry confirmed that HO1-mediated gilteritinib resistance is related to STAT6 phosphorylation in FLT3-ITD AML cell lines and primary individual specimens. Moreover,tumor-bearing mice were employed to determine that HO1 overexpression conferred gilteritinib resistance in vivo. Collectively,these studies illustrate that HO1 may act as a successful treatment target for gilteritinib-resistant FLT3-ITD AML patients. The online version contains supplementary material available at 10.1186/s12935-025-03757-3.
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A. Sivakoses et al. (Mar 2025)
PeerJ 13 1
Triple negative breast cancer cells acquire lymphocyte proteins and genomic DNA during trogocytosis with T cells
Trogocytosis is the process by which a recipient cell siphons small membrane fragments and proteins from a donor cell and can be utilized by cancer cells to avoid immune detection. We observed lymphocyte specific protein expressed by triple negative breast cancer (TNBC) cells via immunofluorescence imaging of patient samples. Image analysis of Cluster of Differentiation 45RA (CD45RA) expression,a naïve T cell specific protein,revealed that all stages of TNBCs express CD45RA. Flow cytometry revealed TNBC cells trogocytose CD45 protein from T cells. We also showed that the acquisition of these lymphoid markers is contact dependent. Confocal and super-resolution imaging further revealed CD45+ spherical structures containing T cell genomic DNA inside TNBC cells after co-culture. Trogocytosis between T cells and TNBC cells altered tumor cell expression of PTPRC,the gene that encodes for CD45. Our results revealed that CD45 is obtained by TNBC cells from T cells via trogocytosis and that TNBC cells express CD45 intracellularly and on the membrane.
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O. Drummond-Guy et al. (Mar 2025)
Frontiers in Oncology 15
Polysialic acid is upregulated on activated immune cells and negatively regulates anticancer immune activity
Suppression of anticancer immune function is a key driver of tumorigenesis. Identifying molecular pathways that inhibit anticancer immunity is critical for developing novel immunotherapeutics. One such molecule that has recently been identified is the carbohydrate polysialic acid (polySia),whose expression is dramatically upregulated on both cancer cells and immune cells in breast cancer patient tissues. The role of polySia in the anticancer immune response,however,remains incompletely understood. In this study,we profile polySia expression on both healthy primary immune cells and on infiltrating immune cells in the tumour microenvironment (TME). These studies reveal polySia expression on multiple immune cell subsets in patient breast tumors. We find that stimulation of primary T-cells and macrophages in vitro induces a significant upregulation of polySia expression. We subsequently show that polySia is appended to a range of different carrier proteins within these immune cells. Finally,we find that selective removal of polySia can significantly potentiate killing of breast cancer cells by innate immune cells. These studies implicate polySia as a significant negative regulator of anticancer immunity.
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K. Tanaka et al. (Apr 2025)
Scientific Reports 15 23
Robust and reproducible human intestinal organoid-derived monolayer model for analyzing drug absorption
Predicting the absorption of orally administered drugs is crucial to drug development. Current in vitro models lack physiological relevance,robustness,and reproducibility,thus hindering reliable predictions. In this study,we developed a reproducible and robust culture method to generate a human intestinal organoid-derived monolayer model that can be applied to study drug absorption through a step-by-step approach. Our model showed similarity to primary enterocytes in terms of the drug absorption-related gene expression profile,tight barrier function,tolerability toward artificial bile juice,drug transporter and metabolizing enzyme function,and nuclear receptor activity. This method can be applied to organoids derived from multiple donors. The permeability of launched 19 drugs in our model demonstrated a correlation with human Fa values,with an R 2 value of 0.88. Additionally,by combining the modeling and simulation approaches,the estimated FaFg values for seven out of nine drugs,including CYP3A substrates,fell within 1.5 times the range of the human FaFg values. Applying this method to the drug discovery process might bridge the gap between preclinical and clinical research and increase the success rates of drug development.
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I. Köhler et al. (Mar 2025)
Frontiers in Cellular Neuroscience 19
Chemogenetic activation of Gq signaling modulates dendritic development of cortical neurons in a time- and layer-specific manner
Designer receptors exclusively activated by designer drugs (DREADDs) are established tools for modulating neuronal activity. Calcium-mobilizing DREADD hM3Dq has been widely used to enhance neuronal activity. hM3Dq activates the Gq protein signaling cascade and mimics the action of native Gq protein-coupled receptors such as muscarinic m1 and m3 receptors leading to calcium release from intracellular storages. Depolarization evoked by increased intracellular calcium levels is an important factor for neuronal maturation. Here,we used repetitive activation of biolistically overexpressed hM3Dq to increase the activity of individual neurons differentiating in organotypic slice cultures of rat visual cortex. HM3Dq was activated by 3 μM clozapine-N-oxide (CNO) dissolved in H 2 O. Transfectants expressing hM3Dq mock-stimulated with H 2 O served as batch-internal controls. Pyramidal cells and multipolar interneurons were analyzed after treatment from DIV 5–10,DIV 10–20,and DIV 15–20 to investigate if Gq signaling is involved in dendritic maturation. Results show that hM3Dq activation accelerated the maturation of apical dendrites of L2/3 pyramidal cells in the early,but no longer in the later time windows. In contrast,dendritic dimensions of L5/6 pyramidal cells and interneurons were not altered at DIV 10. These findings suggest a growth-promoting role of activated Gq signaling selectively for early postnatal L2/3 pyramidal cells. Unexpectedly,hM3Dq activation from DIV 10–20 reduced the dendritic complexity of L5/6 pyramidal cells and multipolar interneurons. Together,results suggest a role of Gq signaling for neuronal differentiation and support evidence that it may also limit dendritic growth.
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Z. Wang et al. (Apr 2025)
European Journal of Medical Research 30 1
Inducing mononuclear cells of patients with CADASIL to construct a CSVD disease model
To produce pluripotent stem cells from peripheral blood mononuclear cells (PBMCs) of a patient with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and culture and differentiate them into vascular organoids,producing a disease model for cerebral small vessel disease (CSVD). (1) PMBCs from patients clinically diagnosed with CADASIL ( NOTCH3 p.R141C) were induced to differentiate into pluripotent stem cells (iPSCs); the quality and differentiation ability of the iPSCs were determined. (2) CADASIL-derived iPSCs and control iPSCs were cultured and differentiated into vascular organoids. The differences in the morphological structure of the two differentiated groups of vascular organoids were observed,and both were identified. (1) No mycoplasma infections were detected in the iPSCs prepared from the PBMCs of patients with CADASIL. The short tandem repeat (STR) identification verified that the iPSCs originated from the patient,and the karyotype was normal. Flow cytometry and immunofluorescence detection revealed that the iPSCs expressed SSEA4,OCT4,and NANOG stem proteins. Tri-germ differentiation testing confirmed that the iPSCs expressed the endoderm markers SOX17 and FOXA2,the mesoderm markers Brachyury and α-SMA,and the ectoderm markers Pax6 and β-III Tubulin. (2) CADASIL-derived iPSCs and control iPSCs were induced to differentiate and produce endothelial networks and vascular networks,ultimately forming vascular organoids. Compared with control vascular organoids,CADASIL vascular organoids exhibited lower growth density,earlier blood vessel sprouting,longer and thinner vascular filaments,and smaller final vascular organoids. The vascular organoids from the two sources expressed the endothelial cell marker CD31,the vascular smooth muscle marker α-SMA,and the pericyte marker PDGFR-β. Reprogramming technology can be used to induce PBMCs to become iPSCs,and a CSVD disease model can be successfully constructed by culturing and differentiating the iPSCs into CADASIL vascular organoids. The NOTCH3 p.R141C mutation suppresses the vascular differentiation process in CADASIL.
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