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Circulation Research Jun 2023Reperfusion therapy is critical to myocardial salvage in the event of a myocardial infarction but is complicated by ischemia-reperfusion injury (IRI). Limited...
BACKGROUND
Reperfusion therapy is critical to myocardial salvage in the event of a myocardial infarction but is complicated by ischemia-reperfusion injury (IRI). Limited understanding of the spatial organization of cardiac cells, which governs cellular interaction and function, has hindered the search for targeted interventions minimizing the deleterious effects of IRI.
METHODS
We used imaging mass cytometry to characterize the spatial distribution and dynamics of cell phenotypes and communities in the mouse left ventricle following IRI. Heart sections were collected from 12 cardiac segments (basal, mid-cavity, apical, and apex of the anterior, lateral, and inferior wall) and 8 time points (before ischemia [I-0H], and postreperfusion [R-0H, R-2H, R-6H, R-12H, R-1D, R-3D, R-7D]), and stained with 29 metal-isotope-tagged antibodies. Cell community analysis was performed on reconstructed images, and the most disease-relevant cell type and target protein were selected for intervention of IRI.
RESULTS
We obtained a total of 251 multiplexed images, and identified 197 063 single cells, which were grouped into 23 distinct cell communities based on the structure of cellular neighborhoods. The cellular architecture was heterogeneous throughout the ventricular wall and exhibited swift changes following IRI. Analysis of proteins with posttranslational modifications in single cells unveiled 13 posttranslational modification intensity clusters and highlighted increased H3K9me3 (tri-methylated lysine 9 of histone H3) as a key regulatory response in endothelial cells during the middle stage of IRI. Erasing H3K9 methylation, by silencing its methyltransferase or overexpressing its demethylase in isolated endothelial cells, attenuated cardiac dysfunction and pathological remodeling following IRI. in vitro, H3K9me3 binding significantly increased at endothelial cell function-related genes upon hypoxia, suppressing tube formation, which was rescued by inhibiting H3K9me3.
CONCLUSIONS
We mapped the spatiotemporal heterogeneity of cellular phenotypes in the adult heart upon IRI, and uncovered H3K9me3 in endothelial cells as a potential therapeutic target for alleviating pathological remodeling of the heart following myocardial IRI.
Topics: Mice; Animals; Myocytes, Cardiac; Endothelial Cells; Myocardial Reperfusion Injury; Myocardium; Reperfusion Injury; Myocardial Infarction
PubMed: 37249015
DOI: 10.1161/CIRCRESAHA.123.322620 -
Nature Nov 2023The skin epidermis is constantly renewed throughout life. Disruption of the balance between renewal and differentiation can lead to uncontrolled growth and tumour...
The skin epidermis is constantly renewed throughout life. Disruption of the balance between renewal and differentiation can lead to uncontrolled growth and tumour initiation. However, the ways in which oncogenic mutations affect the balance between renewal and differentiation and lead to clonal expansion, cell competition, tissue colonization and tumour development are unknown. Here, through multidisciplinary approaches that combine in vivo clonal analysis using intravital microscopy, single-cell analysis and functional analysis, we show how SmoM2-a constitutively active oncogenic mutant version of Smoothened (SMO) that induces the development of basal cell carcinoma-affects clonal competition and tumour initiation in real time. We found that expressing SmoM2 in the ear epidermis of mice induced clonal expansion together with tumour initiation and invasion. By contrast, expressing SmoM2 in the back-skin epidermis led to a clonal expansion that induced lateral cell competition without dermal invasion and tumour formation. Single-cell analysis showed that oncogene expression was associated with a cellular reprogramming of adult interfollicular cells into an embryonic hair follicle progenitor (EHFP) state in the ear but not in the back skin. Comparisons between the ear and the back skin revealed that the dermis has a very different composition in these two skin types, with increased stiffness and a denser collagen I network in the back skin. Decreasing the expression of collagen I in the back skin through treatment with collagenase, chronic UV exposure or natural ageing overcame the natural resistance of back-skin basal cells to undergoing EHFP reprogramming and tumour initiation after SmoM2 expression. Altogether, our study shows that the composition of the extracellular matrix regulates how susceptible different regions of the body are to tumour initiation and invasion.
Topics: Animals; Mice; Cell Transformation, Neoplastic; Collagen; Epidermis; Extracellular Matrix; Skin Neoplasms; Tumor Microenvironment; Carcinoma, Basal Cell; Ear; Collagenases; Aging; Ultraviolet Rays; Mutant Proteins
PubMed: 37968399
DOI: 10.1038/s41586-023-06740-y -
Nature Communications Jul 2023Neuropathy is a feature more frequently observed in pancreatic ductal adenocarcinoma (PDAC) than other tumors. Schwann cells, the most prevalent cell type in peripheral...
Neuropathy is a feature more frequently observed in pancreatic ductal adenocarcinoma (PDAC) than other tumors. Schwann cells, the most prevalent cell type in peripheral nerves, migrate toward tumor cells and associate with poor prognosis in PDAC. To unveil the effects of Schwann cells on the neuro-stroma niche, here we perform single-cell RNA-sequencing and microarray-based spatial transcriptome analysis of PDAC tissues. Results suggest that Schwann cells may drive tumor cells and cancer-associated fibroblasts (CAFs) to more malignant subtypes: basal-like and inflammatory CAFs (iCAFs), respectively. Moreover, in vitro and in vivo assays demonstrate that Schwann cells enhance the proliferation and migration of PDAC cells via Midkine signaling and promote the switch of CAFs to iCAFs via interleukin-1α. Culture of tumor cells and CAFs with Schwann cells conditioned medium accelerates PDAC progression. Thus, we reveal that Schwann cells induce malignant subtypes of tumor cells and CAFs in the PDAC milieu.
Topics: Humans; Cancer-Associated Fibroblasts; Pancreatic Neoplasms; Carcinoma, Pancreatic Ductal; Schwann Cells; Tumor Microenvironment; Cell Line, Tumor; Fibroblasts
PubMed: 37524695
DOI: 10.1038/s41467-023-40314-w -
Science Immunology Dec 2023Studies of human lung development have focused on epithelial and mesenchymal cell types and function, but much less is known about the developing lung immune cells, even...
Studies of human lung development have focused on epithelial and mesenchymal cell types and function, but much less is known about the developing lung immune cells, even though the airways are a major site of mucosal immunity after birth. An unanswered question is whether tissue-resident immune cells play a role in shaping the tissue as it develops in utero. Here, we profiled human embryonic and fetal lung immune cells using scRNA-seq, smFISH, and immunohistochemistry. At the embryonic stage, we observed an early wave of innate immune cells, including innate lymphoid cells, natural killer cells, myeloid cells, and lineage progenitors. By the canalicular stage, we detected naive T lymphocytes expressing high levels of cytotoxicity genes and the presence of mature B lymphocytes, including B-1 cells. Our analysis suggests that fetal lungs provide a niche for full B cell maturation. Given the presence and diversity of immune cells during development, we also investigated their possible effect on epithelial maturation. We found that IL-1β drives epithelial progenitor exit from self-renewal and differentiation to basal cells in vitro. In vivo, IL-1β-producing myeloid cells were found throughout the lung and adjacent to epithelial tips, suggesting that immune cells may direct human lung epithelial development.
Topics: Humans; Immunity, Innate; Cell Differentiation; Lung; Killer Cells, Natural; Epithelial Cells
PubMed: 38100545
DOI: 10.1126/sciimmunol.adf9988 -
Frontiers in Immunology 2023Dysregulated inflammation is associated with many skeletal diseases and disorders, such as osteolysis, non-union of fractures, osteonecrosis, osteoarthritis and...
BACKGROUND
Dysregulated inflammation is associated with many skeletal diseases and disorders, such as osteolysis, non-union of fractures, osteonecrosis, osteoarthritis and orthopaedic infections. We previously showed that continuous infusion of lipopolysaccharide (LPS) contaminated polyethylene particles (cPE) caused prolonged inflammation and impaired bone formation. However, the metabolic and bioenergetic processes associated with inflammation of bone are unknown. Mitochondria are highly dynamic organelles that modulate cell metabolism and orchestrate the inflammatory responses that involve both resident and recruited cells. Glycolytic reprogramming, the shift from oxidative phosphorylation (OXPHOS) to glycolysis causes inappropriate cell activation and function, resulting in dysfunctional cellular metabolism. We hypothesized that impaired immunoregulation and bone regeneration from inflammatory states are associated with glycolytic reprogramming and mitochondrial dysfunction in macrophages (Mφ) and mesenchymal stromal cells (MSCs).
METHODS
We used the Seahorse XF96 analyzer and real-time qPCR to study the bioenergetics of Mφ and MSCs exposed to cPE. To understand the oxygen consumption rate (OCR), we used Seahorse XF Cell Mito Stress Test Kit with Seahorse XF96 analyzer. Similarly, Seahorse XF Glycolytic Rate Assay Kit was used to detect the extracellular acidification rate (ECAR) and Seahorse XF Real-Time ATP Rate Assay kit was used to detect the real-time ATP production rates from OXPHOS and glycolysis. Real-time qPCR was performed to analyze the gene expression of key enzymes in glycolysis and mitochondrial biogenesis. We further detected the gene expression of proinflammatory cytokines in Mφ and genes related to cell differentiation in MSC during the challenge of cPE.
RESULTS
Our results demonstrated that the oxidative phosphorylation of Mφ exposed to cPE was significantly decreased when compared with the control group. We found reduced basal, maximal and ATP-production coupled respiration rates, and decreased proton leak in Mφ during challenge with cPE. Meanwhile, Mφ showed increased basal glycolysis and proton efflux rates (PER) when exposed to cPE. The percentage (%) of PER from glycolysis was higher in Mφ exposed to cPE, indicating that the contribution of the glycolytic pathway to total extracellular acidification was elevated during the challenge of cPE. In line with the results of OCR and ECAR, we found Mφ during cPE challenge showed higher glycolytic ATP (glycoATP) production rates and lower mitochondrial ATP (mitoATP) production rates which is mainly from OXPHOS. Interestingly, MSCs showed enhanced glycolysis during challenge with cPE, but no significant changes in oxygen consumption rates (OCR). In accordance, seahorse assay of real-time ATP revealed glycoATP rates were elevated while mitoATP rates showed no significant differences in MSC during challenge with cPE. Furthermore, Mφ and MSCs exposed to cPE showed upregulated gene expression levels of glycolytic regulators and Mφ exposed to cPE expressed higher levels of pro-inflammatory cytokines.
CONCLUSION
This study demonstrated the dysfunctional bioenergetic activity of bone marrow-derived Mφ and MSCs exposed to cPE, which could impair the immunoregulatory properties of cells in the bone niche. The underlying molecular defect related to disordered mitochondrial function could represent a potential therapeutic target during the resolution of inflammation.
Topics: Humans; Protons; Glycolysis; Inflammation; Mesenchymal Stem Cells; Macrophages; Cytokines; Adenosine Triphosphate
PubMed: 37675119
DOI: 10.3389/fimmu.2023.1199751 -
Nature Communications Sep 2023Aberrant expansion of KRT5 basal cells in the distal lung accompanies progressive alveolar epithelial cell loss and tissue remodelling during fibrogenesis in idiopathic...
Aberrant expansion of KRT5 basal cells in the distal lung accompanies progressive alveolar epithelial cell loss and tissue remodelling during fibrogenesis in idiopathic pulmonary fibrosis (IPF). The mechanisms determining activity of KRT5 cells in IPF have not been delineated. Here, we reveal a potential mechanism by which KRT5 cells migrate within the fibrotic lung, navigating regional differences in collagen topography. In vitro, KRT5 cell migratory characteristics and expression of remodelling genes are modulated by extracellular matrix (ECM) composition and organisation. Mass spectrometry- based proteomics revealed compositional differences in ECM components secreted by primary human lung fibroblasts (HLF) from IPF patients compared to controls. Over-expression of ECM glycoprotein, Secreted Protein Acidic and Cysteine Rich (SPARC) in the IPF HLF matrix restricts KRT5 cell migration in vitro. Together, our findings demonstrate how changes to the ECM in IPF directly influence KRT5 cell behaviour and function contributing to remodelling events in the fibrotic niche.
Topics: Humans; Idiopathic Pulmonary Fibrosis; Extracellular Matrix; Alveolar Epithelial Cells; Biological Transport; Cell Movement; Keratin-5
PubMed: 37758700
DOI: 10.1038/s41467-023-41621-y -
Seminars in Cell & Developmental Biology Dec 2023Apical-Basal polarity is a fundamental property of all epithelial cells that underlies both their form and function. The gut is made up of a single layer of intestinal... (Review)
Review
Apical-Basal polarity is a fundamental property of all epithelial cells that underlies both their form and function. The gut is made up of a single layer of intestinal epithelial cells, with distinct apical, lateral and basal domains. Occluding junctions at the apical side of the lateral domains create a barrier between the gut lumen and the body, which is crucial for tissue homeostasis, protection against gastrointestinal pathogens and for the maintenance of the immune response. Apical-basal polarity in most epithelia is established by conserved polarity factors, but recent evidence suggests that the gut epithelium in at least some organisms polarises by novel mechanisms. In this review, we discuss the recent advances in understanding polarity factors by focussing on work in C. elegans, Drosophila, Zebrafish and Mouse.
Topics: Animals; Mice; Caenorhabditis elegans; Zebrafish; Epithelium; Epithelial Cells; Drosophila; Cell Polarity
PubMed: 36670034
DOI: 10.1016/j.semcdb.2022.12.007 -
Cell Stem Cell Sep 2023Life-long reconstitution of a tissue's resident stem cell compartment with engrafted cells has the potential to durably replenish organ function. Here, we demonstrate...
Life-long reconstitution of a tissue's resident stem cell compartment with engrafted cells has the potential to durably replenish organ function. Here, we demonstrate the engraftment of the airway epithelial stem cell compartment via intra-airway transplantation of mouse or human primary and pluripotent stem cell (PSC)-derived airway basal cells (BCs). Murine primary or PSC-derived BCs transplanted into polidocanol-injured syngeneic recipients give rise for at least two years to progeny that stably display the morphologic, molecular, and functional phenotypes of airway epithelia. The engrafted basal-like cells retain extensive self-renewal potential, evident by the capacity to reconstitute the tracheal epithelium through seven generations of secondary transplantation. Using the same approach, human primary or PSC-derived BCs transplanted into NOD scid gamma (NSG) recipient mice similarly display multilineage airway epithelial differentiation in vivo. Our results may provide a step toward potential future syngeneic cell-based therapy for patients with diseases resulting from airway epithelial cell damage or dysfunction.
Topics: Humans; Animals; Mice; Pluripotent Stem Cells; Cell- and Tissue-Based Therapy; Epithelial Cells; Epithelium; Mice, Inbred NOD; Mice, SCID
PubMed: 37625411
DOI: 10.1016/j.stem.2023.07.014 -
Cell Oct 2023Gravity controls directional growth of plants, and the classical starch-statolith hypothesis proposed more than a century ago postulates that amyloplast sedimentation in...
Gravity controls directional growth of plants, and the classical starch-statolith hypothesis proposed more than a century ago postulates that amyloplast sedimentation in specialized cells initiates gravity sensing, but the molecular mechanism remains uncharacterized. The LAZY proteins are known as key regulators of gravitropism, and lazy mutants show striking gravitropic defects. Here, we report that gravistimulation by reorientation triggers mitogen-activated protein kinase (MAPK) signaling-mediated phosphorylation of Arabidopsis LAZY proteins basally polarized in root columella cells. Phosphorylation of LAZY increases its interaction with several translocons at the outer envelope membrane of chloroplasts (TOC) proteins on the surface of amyloplasts, facilitating enrichment of LAZY proteins on amyloplasts. Amyloplast sedimentation subsequently guides LAZY to relocate to the new lower side of the plasma membrane in columella cells, where LAZY induces asymmetrical auxin distribution and root differential growth. Together, this study provides a molecular interpretation for the starch-statolith hypothesis: the organelle-movement-triggered molecular polarity formation.
Topics: Arabidopsis; Arabidopsis Proteins; Gravity Sensing; Plant Roots; Plastids; Starch; Membrane Proteins
PubMed: 37741279
DOI: 10.1016/j.cell.2023.09.014