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EXO – Beyond the Cell is a quarterly, gold open-access journal published by Science Exploration Press. The journal highlights groundbreaking discoveries on how cells engage with their environments and how these interactions shape biology and medicine. With an emphasis on spatial organization, dynamic communication, and cross-scale integration, EXO – Beyond the Cell serves as a hub for innovative research at the interface of cell biology, technology, and translational science. By fostering rigor, creativity, and accessibility, the journal seeks to accelerate insights that redefine our understanding of life beyond the boundaries of the cell. more >
Articles
Metabolic regulations by p53 in tumour suppression: From cell-intrinsic homeostasis to microenvironmental control
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The transcription factor p53, widely known as the “guardian of the genome”, is a central tumour suppressor that coordinates cellular responses to stress. Upon DNA damage and other perturbations, p53 activates transcriptional programs that promote cell-cycle ...
MoreThe transcription factor p53, widely known as the “guardian of the genome”, is a central tumour suppressor that coordinates cellular responses to stress. Upon DNA damage and other perturbations, p53 activates transcriptional programs that promote cell-cycle arrest, senescence, and apoptosis. However, it has become increasingly clear that these canonical pathways alone do not fully account for the tumour-suppressive functions of p53. A growing body of evidence instead highlights metabolic regulation as a major component of the p53 network. p53 coordinates cellular metabolism to preserve genomic and redox homeostasis, regulate adaptation to metabolic stress, and influence cell-fate decisions through multiple forms of regulated cell death. Beyond cell-intrinsic effects, p53-dependent metabolic programs also shape the tumour microenvironment by modulating nutrient availability, immune-cell function, and intercellular signalling. In this review, we discuss how p53 regulates metabolism at both cell-intrinsic and cell-extrinsic levels and how these functions contribute to tumour suppression. We further examine how distinct p53 mutations reprogram metabolic pathways and alter the tumour-suppressive activities of wild-type p53, emphasizing the context dependence and functional heterogeneity of mutant p53. Together, these findings position metabolic regulation as a central and multifaceted component of p53 biology with important implications for understanding tumour development and therapeutic vulnerability.
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Stephanie Gurres, ... Ivano Amelio
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DOI: https://doi.org/10.70401/EXO.2026.0023 - October 28, 2026
Radical-mediated C7 cholesterol oxidation during erastin-induced ferroptosis
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Aims: Ferroptosis is driven by iron-dependent lipid peroxidation, but whether cholesterol undergoes radical-mediated oxidation during this process remains incompletely understood. We examined the temporal relationship between lipid peroxidation, ...
MoreAims: Ferroptosis is driven by iron-dependent lipid peroxidation, but whether cholesterol undergoes radical-mediated oxidation during this process remains incompletely understood. We examined the temporal relationship between lipid peroxidation, cell death, and C7 cholesterol oxidation during erastin-induced ferroptosis.
Methods: Human SH-SY5Y cells were treated with erastin. Cell viability, lipid hydroperoxides, and lipid radicals were assessed using Alamar Blue, Liperfluo, and LipiRADICAL, respectively. Total 7α-hydroxycholesterol (t7α-OHCh), total 7β-hydroxycholesterol (t7β-OHCh), and 7-ketocholesterol (7-ketoCh) were quantified by gas chromatography–mass spectrometry (GC–MS) after triphenylphosphine reduction and saponification.
Results: Erastin-induced cell death was suppressed by deferoxamine, ferrostatin-1, and α-tocopherol. Liperfluo fluorescence increased before detectable LipiRADICAL fluorescence and loss of cell viability. t7α-OHCh increased during the early phase, whereas t7β-OHCh increased later; no statistically significant change in 7-ketoCh was detected. Because t7α-OHCh and t7β-OHCh represent composite pools of pre-existing free and esterified hydroxycholesterols and hydroperoxide-derived products, the early t7α-OHCh signal cannot distinguish enzymatic hydroxylation from a 7α-hydroperoxycholesterol (7α-OOHCh)-derived product. The increase in t7β-OHCh together with the overall C7 stereochemical profile is consistent with radical-mediated C7 cholesterol oxidation.
Conclusion: These findings support radical-mediated C7 cholesterol oxidation as an early component of erastin-induced ferroptotic lipid damage. The biological activity and extracellular transfer of these products remain to be established.
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Yuta Akiba, ... Yoshiro Saito
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DOI: https://doi.org/10.70401/EXO.2026.0022 - October 28, 2026
Beyond slides: The era of 3D histology
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Histology has long served as the foundation of tissue diagnosis, yet its reliance on thin two-dimensional (2D) sections incompletely captures the spatial continuity, volumetric heterogeneity, and multicellular architecture of biological tissues. Recent ...
MoreHistology has long served as the foundation of tissue diagnosis, yet its reliance on thin two-dimensional (2D) sections incompletely captures the spatial continuity, volumetric heterogeneity, and multicellular architecture of biological tissues. Recent advances in volumetric imaging, spatial omics, label-free optical pathology, and artificial intelligence are enabling tissue analysis beyond the conventional glass slide. In this Perspective, we discuss the emergence of three-dimensional (3D) histology and the technological developments driving the transition from planar sampling to volumetric tissue analysis. We highlight how the added spatial dimension can reveal diagnostically relevant features that are only partially represented in conventional sections, and discuss efforts to extend molecular profiling into intact tissues through multiplexed imaging and volumetric spatial omics. We further examine the growing role of label-free modalities, particularly stimulated Raman scattering microscopy, for rapid and minimally destructive pathology. Finally, we consider the computational foundations required to reconstruct, align and interpret volumetric data, including emerging applications in virtual histology and molecular prediction. Together, these developments suggest that 3D histology is evolving into a broader framework for integrating tissue morphology, molecular state, and function within intact spatial contexts, with emerging opportunities for biological discovery and precision medicine.
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Zihang He, ... Lixue Shi
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DOI: https://doi.org/10.70401/EXO.2026.0021 - September 30, 2026
Predicting spatial transcriptomics from histology images: Progress, challenges, and directions
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Spatial transcriptomics (ST) maps gene expression within intact tissues, but its cost and technical complexity limit broad adoption. A growing body of deep-learning methods now seeks to infer ST directly from routine histology images, especially hematoxylin ...
MoreSpatial transcriptomics (ST) maps gene expression within intact tissues, but its cost and technical complexity limit broad adoption. A growing body of deep-learning methods now seeks to infer ST directly from routine histology images, especially hematoxylin and eosin (H&E)-stained slides, with the aim of turning archived pathology material into virtual molecular data. This review examines more than 40 ST prediction models, comparing their data requirements, modelling strategies, evaluation practices, and translational potential. Recent advances in model architecture, histology foundation models, and higher-resolution in situ ST platforms have improved prediction performance and expanded the range of potential applications. However, most current methods still show limited robustness and generalisability, with performance constrained primarily by the quantity, quality, and diversity of available ST training data. Comparisons between models also remain difficult due to inconsistent pre-processing pipelines, training datasets and evaluation strategies. The field is increasingly recognising that progress depends not only on more sophisticated models, but also on standardised benchmarks, improved data harmonisation and clearer evaluation frameworks. Despite these limitations, ST prediction is already showing utility in research settings, including biomarker discovery, tissue domain inference, molecular super-resolution and large-scale analysis of archived histology cohorts. Emerging applications also include patient stratification, virtual molecular profiling and multi-modal pathology systems that integrate histology, transcriptomics and language models. As datasets continue to expand and models become more reliable, ST prediction has the potential to become an important component of next-generation digital pathology workflows.
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Kexin Xu, ... Agne Antanaviciute
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DOI: https://doi.org/10.70401/EXO.2026.0020 - September 10, 2026
Single-cell and spatial multi-omics for mapping the brain across molecular layers
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Understanding how molecular mechanisms occur and shape brain function and dysfunction remains a central challenge in neuroscience. Although bulk omics methods have contributed significantly to the field, they fail to address the cellular and spatial heterogeneity ...
MoreUnderstanding how molecular mechanisms occur and shape brain function and dysfunction remains a central challenge in neuroscience. Although bulk omics methods have contributed significantly to the field, they fail to address the cellular and spatial heterogeneity of the brain. Single-cell and spatial multi-omics approaches emerged to address these limitations by enabling integrated, high-resolution profiling of molecular layers while preserving cellular and tissue context. However, despite their impact on basic neuroscience, the clinical translation of these methods remains limited by cost, technical complexity, and analytical challenges. In this review, we summarize recent advances in single-cell and spatial multi-omics applied to brain research, critically evaluating their technological capabilities, translational potential, and current limitations. We further highlight emerging directions, including spatiotemporal integration, morphomics, improved reproducibility, and the expansion of multi-omics research to biologically and environmentally diverse populations.
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Vitor Ikeda Ito-Silva, ... Daniel Martins-de-Souza
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DOI: https://doi.org/10.70401/EXO.2026.0019 - August 14, 2026
Computational workflows and data infrastructures for spatial omics analysis
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Spatial omics is a broad term referring to technologies that allow for biomolecules to be observed within their native tissue context. These technologies have been used by biomedical researchers to gain a better understanding of cellular interactions, tumor ...
MoreSpatial omics is a broad term referring to technologies that allow for biomolecules to be observed within their native tissue context. These technologies have been used by biomedical researchers to gain a better understanding of cellular interactions, tumor microenvironment dynamics, and immune cell infiltration. While the basic outputs, such as spatial coordinates, segmentation masks, and transcript/protein matrices, are provided by the instrument software, the true biological insights come from several downstream, specialized analysis steps. Since spatial omics remains a relatively new field, no unified analysis pipeline has yet been established to encompass all platforms. Most workflows are adapted from single-cell RNA sequencing analysis frameworks, while incorporating additional steps that are specific to spatial data, especially for imaging-based technologies. At the same time, the diversity of platforms, data modalities, and output formats has introduced substantial challenges for data representation, interoperability, and cross-platform integration, highlighting the need for flexible, spatially aware, and user-friendly data structures made specifically for imaging-based data, not merely adapted from other methods. This review summarizes the general analytical steps following spatial omics data acquisition, commonly used data infrastructures and tools, existing gaps, and future directions in the field.
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Margaret Alexander, ... Jasmine Plummer
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DOI: https://doi.org/10.70401/EXO.2026.0010 - May 15, 2026
Predicting spatial transcriptomics from histology images: Progress, challenges, and directions
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Spatial transcriptomics (ST) maps gene expression within intact tissues, but its cost and technical complexity limit broad adoption. A growing body of deep-learning methods now seeks to infer ST directly from routine histology images, especially hematoxylin ...
MoreSpatial transcriptomics (ST) maps gene expression within intact tissues, but its cost and technical complexity limit broad adoption. A growing body of deep-learning methods now seeks to infer ST directly from routine histology images, especially hematoxylin and eosin (H&E)-stained slides, with the aim of turning archived pathology material into virtual molecular data. This review examines more than 40 ST prediction models, comparing their data requirements, modelling strategies, evaluation practices, and translational potential. Recent advances in model architecture, histology foundation models, and higher-resolution in situ ST platforms have improved prediction performance and expanded the range of potential applications. However, most current methods still show limited robustness and generalisability, with performance constrained primarily by the quantity, quality, and diversity of available ST training data. Comparisons between models also remain difficult due to inconsistent pre-processing pipelines, training datasets and evaluation strategies. The field is increasingly recognising that progress depends not only on more sophisticated models, but also on standardised benchmarks, improved data harmonisation and clearer evaluation frameworks. Despite these limitations, ST prediction is already showing utility in research settings, including biomarker discovery, tissue domain inference, molecular super-resolution and large-scale analysis of archived histology cohorts. Emerging applications also include patient stratification, virtual molecular profiling and multi-modal pathology systems that integrate histology, transcriptomics and language models. As datasets continue to expand and models become more reliable, ST prediction has the potential to become an important component of next-generation digital pathology workflows.
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Kexin Xu, ... Agne Antanaviciute
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DOI: https://doi.org/10.70401/EXO.2026.0020 - September 10, 2026
Approaches to deorphanize secretome: Classical, computational, and next generation strategies to reveal ligand-receptor networks
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Secreted proteins mediate intercellular and inter-organ communication and are essential for coordinating physiological processes across tissues. Advances in proteomics and proximity labeling have greatly expanded the catalog of circulating secreted ...
MoreSecreted proteins mediate intercellular and inter-organ communication and are essential for coordinating physiological processes across tissues. Advances in proteomics and proximity labeling have greatly expanded the catalog of circulating secreted factors; however, for many of these molecules, their cognate receptors and mechanisms of action remain unknown. This lack of receptor annotation represents a major bottleneck in understanding systemic signaling networks and translating secretome discoveries into biological insights. In this review, we summarize and evaluate the strengths and limitations of current strategies for deorphanizing secreted proteins, including 1) biochemical approaches such as affinity purification–mass spectrometry and crosslinking-based receptor capture, 2) genetic screening strategies in both in vivo and in vitro systems, including RNA interference and Clustered Regularly-Interspaced Short Palindromic Repeats (CRISPR)-based perturbation and activation platforms, and 3) computational frameworks based on AI-driven protein structure modeling. Finally, we outline future directions aimed at accelerating ligand–receptor identification, including multiplexed screening platforms, approaches to improve sensitivity for low-affinity interactions, synthetic biology tools that convert transient binding events into stable readouts, and integration with single-cell and spatial transcriptomic technologies. Together, these advances provide a roadmap for transforming classical ligand deorphanization into a scalable, context-aware framework for decoding inter-organ communication.
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Myeonghoon Han, Norbert Perrimon
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DOI: https://doi.org/10.70401/EXO.2026.0008 - May 11, 2026
EXO - Beyond the Cell, a journal about how cells interact with their environment
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Brent R. Stockwell
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DOI: https://doi.org/10.70401/EXO.2026.0001 - January 13, 2026
Human iPSC-derived macrophages for studying intrinsic and extrinsic factors in cystic fibrosis
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Background: Cystic fibrosis (CF) is a progressive genetic disease characterized by defective ion transport, mucus accumulation, chronic infection, and inflammation that drive airway damage and ultimately end-stage lung failure. Previous studies ...
MoreBackground: Cystic fibrosis (CF) is a progressive genetic disease characterized by defective ion transport, mucus accumulation, chronic infection, and inflammation that drive airway damage and ultimately end-stage lung failure. Previous studies show that high levels of proteolytic enzymes in the sputum of CF patients correlate with declining lung function, but the related effects on distal lung extracellular matrix (ECM) and immune responses are unclear.
Methods: To address this gap, induced pluripotent stem cell (iPSC) lines from healthy donors and CF patients were differentiated into macrophages, and stimulated with lipopolysaccharide (LPS) to compare their inflammatory responses. Bulk RNA sequencing, functional assays, and secreted protein profiling revealed key differences between healthy and CF-derived macrophages, providing insight into how these cells may contribute to inflammatory responses in CF patients. Further, human lung ECM from distal CF lung tissue was isolated, used to generate ECM biomaterials, and combined with iPSC-derived macrophages from healthy and CF donors in vitro. Macrophage phenotype was evaluated through cytokine profiling and RNA sequencing.
Results: CF macrophage inflammation was dysregulated, with elevated baseline IL-8, IL-18, and MCP-1 expression, and a blunted inflammatory response to CF ECM compared to healthy macrophages. By using CF ECM and healthy macrophages, we characterized how healthy cells may be altered in a persistent CF milieu after anticipated CFTR modulator therapy.
Conclusion: These findings reveal altered innate immune behavior in CF and demonstrate the utility of iPSC-derived macrophages for modeling extrinsic immune-ECM interactions in disease.
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Daniel Naveed Tavakol, ... Gordana Vunjak-Novakovic
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DOI: https://doi.org/10.70401/EXO.2026.0005 - April 10, 2026
Computational workflows and data infrastructures for spatial omics analysis
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Spatial omics is a broad term referring to technologies that allow for biomolecules to be observed within their native tissue context. These technologies have been used by biomedical researchers to gain a better understanding of cellular interactions, tumor ...
MoreSpatial omics is a broad term referring to technologies that allow for biomolecules to be observed within their native tissue context. These technologies have been used by biomedical researchers to gain a better understanding of cellular interactions, tumor microenvironment dynamics, and immune cell infiltration. While the basic outputs, such as spatial coordinates, segmentation masks, and transcript/protein matrices, are provided by the instrument software, the true biological insights come from several downstream, specialized analysis steps. Since spatial omics remains a relatively new field, no unified analysis pipeline has yet been established to encompass all platforms. Most workflows are adapted from single-cell RNA sequencing analysis frameworks, while incorporating additional steps that are specific to spatial data, especially for imaging-based technologies. At the same time, the diversity of platforms, data modalities, and output formats has introduced substantial challenges for data representation, interoperability, and cross-platform integration, highlighting the need for flexible, spatially aware, and user-friendly data structures made specifically for imaging-based data, not merely adapted from other methods. This review summarizes the general analytical steps following spatial omics data acquisition, commonly used data infrastructures and tools, existing gaps, and future directions in the field.
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Margaret Alexander, ... Jasmine Plummer
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DOI: https://doi.org/10.70401/EXO.2026.0010 - May 15, 2026
Predicting spatial transcriptomics from histology images: Progress, challenges, and directions
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Spatial transcriptomics (ST) maps gene expression within intact tissues, but its cost and technical complexity limit broad adoption. A growing body of deep-learning methods now seeks to infer ST directly from routine histology images, especially hematoxylin ...
MoreSpatial transcriptomics (ST) maps gene expression within intact tissues, but its cost and technical complexity limit broad adoption. A growing body of deep-learning methods now seeks to infer ST directly from routine histology images, especially hematoxylin and eosin (H&E)-stained slides, with the aim of turning archived pathology material into virtual molecular data. This review examines more than 40 ST prediction models, comparing their data requirements, modelling strategies, evaluation practices, and translational potential. Recent advances in model architecture, histology foundation models, and higher-resolution in situ ST platforms have improved prediction performance and expanded the range of potential applications. However, most current methods still show limited robustness and generalisability, with performance constrained primarily by the quantity, quality, and diversity of available ST training data. Comparisons between models also remain difficult due to inconsistent pre-processing pipelines, training datasets and evaluation strategies. The field is increasingly recognising that progress depends not only on more sophisticated models, but also on standardised benchmarks, improved data harmonisation and clearer evaluation frameworks. Despite these limitations, ST prediction is already showing utility in research settings, including biomarker discovery, tissue domain inference, molecular super-resolution and large-scale analysis of archived histology cohorts. Emerging applications also include patient stratification, virtual molecular profiling and multi-modal pathology systems that integrate histology, transcriptomics and language models. As datasets continue to expand and models become more reliable, ST prediction has the potential to become an important component of next-generation digital pathology workflows.
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Kexin Xu, ... Agne Antanaviciute
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DOI: https://doi.org/10.70401/EXO.2026.0020 - September 10, 2026
Extracellular vesicles in Drosophila and mammals: Conserved mechanisms and emerging functional roles
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Extracellular vesicles (EVs) are membrane-enclosed particles released by cells carrying proteins, lipids, metabolites and nucleic acids that can alter the behavior of recipient cells. In mammalian systems, EVs have been studied extensively as important ...
MoreExtracellular vesicles (EVs) are membrane-enclosed particles released by cells carrying proteins, lipids, metabolites and nucleic acids that can alter the behavior of recipient cells. In mammalian systems, EVs have been studied extensively as important mediators of intercellular and interorgan communication in development, tissue homeostasis, immunity, regeneration, metabolism, cancer and neurobiology. In parallel, Drosophila has emerged as a powerful in vivo model for EV research owing to its genetic tractability and the availability of well-established tools for studying interorgan communication. Work in Drosophila has shown that EVs participate in synaptic cargo transfer, developmental and reproductive signaling, neuronal homeostasis and systemic immune responses. Importantly, most of the pathways that regulate endosomal sorting, multivesicular body dynamics, membrane budding and vesicle secretion are conserved between flies and mammals. This review summarizes current understanding of EV nomenclature, biogenesis, cargo selection and biological function, with emphasis on points of convergence and divergence between mammalian and Drosophila systems. It further discusses the strengths and limitations of Drosophila as a model for mammalian EV biology and highlights how comparative approaches can sharpen mechanistic insight and translational EV studies.
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Kyosuke Yanagawa, Norbert Perrimon
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DOI: https://doi.org/10.70401/EXO.2026.0014 - June 23, 2026
Human iPSC-derived macrophages for studying intrinsic and extrinsic factors in cystic fibrosis
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Background: Cystic fibrosis (CF) is a progressive genetic disease characterized by defective ion transport, mucus accumulation, chronic infection, and inflammation that drive airway damage and ultimately end-stage lung failure. Previous studies ...
MoreBackground: Cystic fibrosis (CF) is a progressive genetic disease characterized by defective ion transport, mucus accumulation, chronic infection, and inflammation that drive airway damage and ultimately end-stage lung failure. Previous studies show that high levels of proteolytic enzymes in the sputum of CF patients correlate with declining lung function, but the related effects on distal lung extracellular matrix (ECM) and immune responses are unclear.
Methods: To address this gap, induced pluripotent stem cell (iPSC) lines from healthy donors and CF patients were differentiated into macrophages, and stimulated with lipopolysaccharide (LPS) to compare their inflammatory responses. Bulk RNA sequencing, functional assays, and secreted protein profiling revealed key differences between healthy and CF-derived macrophages, providing insight into how these cells may contribute to inflammatory responses in CF patients. Further, human lung ECM from distal CF lung tissue was isolated, used to generate ECM biomaterials, and combined with iPSC-derived macrophages from healthy and CF donors in vitro. Macrophage phenotype was evaluated through cytokine profiling and RNA sequencing.
Results: CF macrophage inflammation was dysregulated, with elevated baseline IL-8, IL-18, and MCP-1 expression, and a blunted inflammatory response to CF ECM compared to healthy macrophages. By using CF ECM and healthy macrophages, we characterized how healthy cells may be altered in a persistent CF milieu after anticipated CFTR modulator therapy.
Conclusion: These findings reveal altered innate immune behavior in CF and demonstrate the utility of iPSC-derived macrophages for modeling extrinsic immune-ECM interactions in disease.
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Daniel Naveed Tavakol, ... Gordana Vunjak-Novakovic
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DOI: https://doi.org/10.70401/EXO.2026.0005 - April 10, 2026
Ferroptosis spreading through propagative signals
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Ferroptosis is a regulated mechanism of cell death caused by the uncontrolled peroxidation of cellular lipids that has an unusual ability to propagate or spread between cells. Here, we review studies identifying regulators of ferroptosis propagation to consider ...
MoreFerroptosis is a regulated mechanism of cell death caused by the uncontrolled peroxidation of cellular lipids that has an unusual ability to propagate or spread between cells. Here, we review studies identifying regulators of ferroptosis propagation to consider a working model that might explain this unusual feature. Recent findings implicating the spread of lipid peroxides and iron suggest that these main catalysts of ferroptosis may also be primary vehicles that can spread death between cells. Experiments revealing localized versus long-range effects of propagation are discussed, as well as sensitizing factors that may expand the propagative potential of death induced by Class II ferroptosis-inducing compounds. As ferroptosis propagation may underlie the loss of large groups of cells in degenerative diseases and may also have a specialized role in normal development, consideration of how ferroptosis can spread through propagative signals may be important for understanding both normal tissue dynamics and disease.
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Saloni K. Hombalkar, ... Michael Overholtzer
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DOI: https://doi.org/10.70401/EXO.2026.0011 - May 26, 2026
Frontier Forums
EXO Chats
Cracking the Spatial Omics Data Bottleneck: From Images to Biological Insight
Department of Biological Sciences, Department of Chemistry, Department of Pathology and Cell Biology, Columbia University, New York, NY, USA.
Dr. Jasmine Plummer
Center for Spatial Omics, St. Jude Children's Research Hospital, Memphis, TN, USA.
Exercise Oncology: A Discovery Engine for New Cancer Treatment Strategies
Department of Biological Sciences, Department of Chemistry, Department of Pathology and Cell Biology, Columbia University, New York, NY, USA.
Prof. Dafna Bar-Sagi
Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, New York, NY, USA.
Dr. Emma S. Kurz
Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Beyond the Cell: How the Microenvironment Shapes Macrophage-Driven Inflammation in Cystic Fibrosis
Department of Biological Sciences, Department of Chemistry, Department of Pathology and Cell Biology, Columbia University, New York, NY, USA.
Prof. Gordana Vunjak-Novakovic
Department of Biomedical Engineering, Columbia University, New York, NY, USA.
Dr. Daniel Naveed Tavakol
Department of Biomedical Engineering, Columbia University, New York, NY, USA.
Dr. Pamela L. Graney
Department of Biomedical Engineering, Columbia University, New York, NY, USA.

