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Biology subjects

Sugimura, R.

Publications and source records attributed to Sugimura, R..

10 recordsLinked to original sources

Blood originates in hypoblasts during embryonic development

Blood is essential for oxygen supply throughout life. The emergence of blood in the human embryo remains poorly understood. Our study leverages multiple stem cell embryo models and advanced lineage barcoding to unveil that hypoblast, originally regarded as forming the yolk sac wall, is heterogeneous and contributes to CDX2+ extraembryonic mesoderm, followed by hemoglobin+ cells as the first blood cells. CDX2 marks the hypoblast-to-hemoglobin+ cell trajectory that functionally sustains oxygen levels in embryo models. These hemoglobin+ cells molecularly and functionally resemble phagocytes. We show that the erythro-core regulatory network is poised in hypoblasts, and its boost endows erythropoiesis to both hypoblasts and phagocytes. Hypoblasts are the origin of the first blood in humans and non-human primates, providing a conceptual framework that earlier blood generation than expected fills the gap in the establishment of circulation. Further, the hypoblast is a place where primates may repurpose the phagocyte program to carry oxygen throughout embryos. HighlightsO_LIBarcode-traced hypoblast fate in human embryo models; C_LIO_LIThe first blood comes from the hypoblast that contributes to hemoglobin+ phagocyte-like cells; C_LIO_LICDX2 marks hypoblast blood that sustains oxygen supply in embryos before heart formation; C_LIO_LIErythro-core regulatory network endows erythropoiesis to human hypoblasts and phagocytes. C_LI

developmental biology↗

Homogeneously crosslinked in situ hydrogel enclosing high-density human-cancer cells promotes vascularized in vivo tumor modeling for immune cell therapy

Cancer models in animal studies play a central role in cancer research, particularly in investigating vascularized tumor tissues for the validation of immune cell therapies. However, xenografts relying solely on cancer cells are ineffective for optimal tumor tissue formation. Additionally, tumor modeling using hydrogels with cancer cells to promote vascularization often leaves behind residual biomaterials that inhibit integration with surrounding tissues. To address these issues, we utilized a straightforward in vivo vascularized tumor modeling method with a completely degradable, crosslinker-free carboxymethyl chitosan (CMCTS)/oxidized hyaluronic acid (OHA) hydrogel that encapsulates high-density human cancer cells for in situ injection. The CMCTS/oHA hydrogel was fully degraded within 3 weeks, enabling three-dimensional (3D) cell condensation in vitro. 2 weeks after subcutaneous injection in mice, solid tumors formed, with native host vasculature infiltrating the transplanted human cancer cells, confirming spontaneous hydrogel degradation. Following this, human macrophages were administered via tail vein injection, enhancing the accumulation of mouse immune cells in the humanized tumor twofold and showing murine macrophages adjacent to the vasculature. This study thus provides proof-of-concept for a facile and fully vascularized humanized tumor model in mice for validating immune cell therapies. HIGHLIGHTSO_LIThe oHA was prepared using sodium periodate treatment, which facilitated the formation of in situ CMCTS/oHA hydrogels C_LIO_LICMCTS/oHA hydrogels completely degraded within a short period, allowing for 3D cell condensation C_LIO_LIHigh-density cell-laden CMCTS/oHA hydrogels were injected subcutaneously in mice, resulting in the generation of a vascularized solid tumor C_LIO_LIThe transplanted therapeutic cell was observed to adhere to the tumor tissue through the bloodstream C_LI

bioengineering↗

Lipidic and senescent macrophages predict progression and response to combinatorial immunotherapy in triple-negative breast cancer

Immune cell subsets in the tumor predict prognosis. Identifying reliable subsets consistently in multiple patients is clinically important. Whats more advantageous to the field is if such subsets can be a target of immunotherapy. Here we analyzed single-cell RNA-sequencing datasets of patients with triple-negative breast cancer and identified APOE or FABP5-expressing macrophages correlated with poor prognosis. Further validation with TCGA-BRCA cohort detailed molecular signatures of these macrophages as lipidic and senescent. Our receptor-ligand mapping identified lipidic and senescent macrophages both suppress T-lymphoid and myeloid immunogenicity. Finally, we discovered that immune checkpoint therapy combined with chemotherapy reprogrammed anti-tumor microenvironment enriched with FOLR2+ macrophages facilitated T-cell activations. This suggests that lipidic and senescent macrophages could be a therapeutic target of immune checkpoint therapy.

cancer biology↗

SARS-CoV-2 infection activates inflammatory macrophages in vascular immune organoids

SARS-CoV-2 provokes devastating tissue damage by cytokine release syndrome and leads to multi-organ failure. Modeling the process of immune cell activation and subsequent tissue damage is a significant task. Organoids from human tissues advanced our understanding of SARS-CoV-2 infection mechanisms though, they are missing crucial components: immune cells and endothelial cells. This study aims to generate organoids with these components. We established vascular immune organoids from human pluripotent stem cells and examined the effect of SARS-CoV-2 infection. We demonstrated that infections activated inflammatory macrophages. Notably, the upregulation of interferon signaling supports macrophages role in cytokine release syndrome. We propose vascular immune organoids are a useful platform to model and discover factors that ameliorate SARS-CoV-2-mediated cytokine release syndrome.

immunology↗

Single-cell mitochondrial variant enrichment resolved clonal tracking and spatial architecture in human embryonic hematopoiesis

The ability to perform lineage tracing at the single-cell level is critical to reconstructing dynamic transitions during cell differentiation. However, prospective tracing approaches inevitably encounter outstanding challenges including barcoding precision, barcode diversity, and detection efficiency, which can skew inferred lineage relationships. Human pluripotent stem cells (hPSCs) even face risks of DNA-damage-induced toxicity-related cell death. We explored the use of naturally occurring somatic mutations in mitochondrial transcripts detected in single-cell RNA-seq as genetic lineage barcodes in hPSCs. In this study, we used an enrichment of scRNA-seq mitochondrial reads and a robust computational method to identify clonally relevant mitochondrial variants as endogenous genetic barcodes for clonal tracking of early embryonic hematopoiesis from hPSC. We modeled the development of embryonic tissues from hPSCs and delineated cell fate specification by integrating synthetic barcoding with mitochondrial lineage tracing. Using a biophysical model, we reconstructed the sequential transcriptional logic of fate specification and its underlying regulatory network. We further applied mitochondrial lineage tracing to spatial transcriptomics, which enabled us to identify the spatial clonal architecture of human embryonic organoids. Our analysis revealed that this spatial zonation was orchestrated by NOTCH-mediated crosstalk between stromal cells and hematopoietic progenitors. Our multi-modal framework links clonal dynamics with niche-specific fate decisions, providing a generalizable approach to dissecting tissue organization in development and disease. This study underscores the utility of mitochondrial variants as endogenous markers for high-resolution spatial clonal tracking in stem cell-derived organoid models of human development.

developmental biology↗

SpatialScope: A unified approach for integrating spatial and single-cell transcriptomics data using deep generative models

The rapid emergence of spatial transcriptomics (ST) technologies are revolutionizing our under-standing of tissue spatial architecture and their biology. Current ST technologies based on either next generation sequencing (seq-based approaches) or fluorescence in situ hybridization (image-based approaches), while providing hugely informative insights, remain unable to provide spatial characterization at transcriptome-wide single-cell resolution, limiting their usage in resolving detailed tissue structure and detecting cellular communications. To overcome these limitations, we developed SpatialScope, a unified approach to integrating scRNA-seq reference data and ST data that leverages deep generative models. With innovation in model and algorithm designs, SpatialScope not only enhances seq-based ST data to achieve single-cell resolution, but also accurately infers transcriptome-wide expression levels for image-based ST data. We demonstrate the utility of SpatialScope through comprehensive simulation studies and then apply it to real data from both seq-based and image-based ST approaches. SpatialScope provides a spatial characterization of tissue structures at transcriptome-wide single-cell resolution, greatly facilitating the downstream analysis of ST data, such as detection of cellular communication by identifying ligand-receptor interactions from seq-based ST data, localization of cellular subtypes, and detection of spatially differently expressed genes.

bioinformatics↗

PD-L1 regulates inflammatory macrophage development from human pluripotent stem cells by maintaining interferon-gamma signal

PD-L1 (programmed death-ligand 1) serves as a pivotal immune checkpoint in both the innate and adaptive immune systems. PD-L1 is expressed in macrophages in response to interferon-gamma (IFN{gamma}). We examined whether PD-L1 might regulate macrophage development. We established PD-L1-/- human pluripotent stem cells, differentiated them into macrophages, and observed a 60% reduction of CD11B+CD45+ macrophages in PD-L1-/-, orthogonally verified with PD-L1 inhibitor BMS-1166 reduced macrophages to the same fold. Single-cell RNA sequencing further confirmed the 60% reduction of macrophages as well as the down-regulation of macrophage-defining transcription factors SPI1, KLF6, and MAFB. Further, PD-L1-/- macrophages reduced the level of inflammatory signals such as NF{kappa}B, TNF, and chemokines CXCL and CCL families. Whilst anti-inflammatory TGF-{beta} was upregulated. Finally, we identified that PD-L1-/- macrophages significantly down-regulated interferon-stimulated genes (ISGs) despite IFN{gamma} in differentiation media. Mechanistically, PD-L1-/- macrophages reduced IFNGR1 expression explaining that cells could not respond to IFN{gamma}. These data suggest that PD-L1 regulates inflammatory macrophage development by maintaining the IFN{gamma} signal.

immunology↗

Organoid-based single-cell spatiotemporal gene expression landscape of human embryonic development and hematopoiesis

Single-cell level characterization of embryonic development is a major benchmark of human developmental biology. Spatiotemporal analysis of stem-cell-derived embryos offers conceptual and technical advances in the field. Here, we defined the single-cell spatiotemporal gene expression landscape of human embryonic development with stem-cell-derived organoids. We established the human embryonic organoid (HEMO) from expanded potential stem cells and achieved both embryonic and extraembryonic tissues in the same organoid. Time-series single-cell RNA sequencing paired with single-cell resolution spatial revealed human embryonic development signatures such as extraembryonic placenta, yolk sac hematopoiesis neural crest, blood vessels, and cardiac mesoderm. Hematopoietic tissues eventually predominated HEMO with erythropoiesis, mekagaryopiesis, and myelopoiesis. Cell-cell communication network analysis demonstrated that trophoblast-like tissues supplied WNT signaling in neural crest cells to facilitate maturation and migration. Single-cell resolution spatial transcriptomics defined the yolk sac erythro-megakaryopoietic niche. Vitronectin-integrin signaling, a major contributor to megakaryocyte maturation, was predominant in the yolk sac niche in HEMO and to human fetal samples. Overall, our study advances the spatiotemporal analysis of human embryonic development in stem-cell-derived organoids. HighlightsO_LIModeling human embryonic development from stem cells C_LIO_LIUsed of both 10X Chromium and 10X Visium to define the gene expression landscape of embryonic development and hematopoiesis C_LIO_LIWNT signaling as a regulator of neural crest maturation and EMT C_LIO_LIVTN-ITGA2B as the main contributor to Mk maturation within the yolk sac erythro-megakaryopoietic niche C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=158 HEIGHT=200 SRC="FIGDIR/small/505700v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@1710d00org.highwire.dtl.DTLVardef@10ca8e0org.highwire.dtl.DTLVardef@2310d1org.highwire.dtl.DTLVardef@252728_HPS_FORMAT_FIGEXP M_FIG C_FIG

developmental biology↗

Angiocrine factors from HUVECs amplify erythroid cells

Erythropoiesis is regulated by microenvironmental factors from the vasculature. Enhanced erythropoiesis, which occurs under stress or during development, amplifies erythroid cells to meet the demand of red blood cells. This process uncouples cell division and differentiation, thus the accumulated erythroid cells remain undifferentiated in the vasculature. However, little is known about how vascular endothelial cells (ECs) regulate erythropoiesis. Here we identified that human umbilical vein endothelial cells (HUVECs) keep erythroid cells undifferentiated and amplify their number. We determined that HUVECs amplify erythroid cells via secreted angiocrine factors. The expression profile of these factors suggested that they resemble macrophage-crines for enhanced erythropoiesis. Molecularly, HUVECs mediate the activation of ERK signaling. These data indicate that angiocrine factors from HUVECs enhance erythropoiesis via the amplification of undifferentiated erythroid cells. Our study contributes to the ultimate goal of harnessing erythropoiesis to replace blood transfusions.

developmental biology↗

Biomimetic Aorta-Gonad-Mesonephros on-a-Chip to Study Human Developmental Hematopoiesis

We established a multilayer microfluidic Aorta-Gonad-Mesonephros (AGM)-on-a-chip to emulate developmental hematopoiesis from human pluripotent stem cells. We show that the AGM-chip efficiently derives endothelial-to-hematopoietic transition (EHT) in the presence of mesenchymal stroma and endothelial cells. The AGM-chip could dissect the cellular and molecular mechanisms of human developmental hematopoiesis.

bioengineering↗