Macrophage morphological plasticity and migration is Rac signalling and MMP9 dependant

Abstract In vitro, depending on extracellular matrix (ECM) architecture, macrophages migrate either in amoeboid or mesenchymal mode; while the first is a general trait of leukocytes, the latter is associated with tissue remodelling via Matrix Metalloproteinases (MMPs). To assess whether these stereotyped migrations could be also observed in a physiological context, we used the zebrafish embryo and monitored macrophage morphology, behaviour and capacity to mobilisation haematopoietic stem/progenitor cells (HSPCs), as a final functional readout. Morphometric analysis identified 4 different cell shapes. Live imaging revealed that macrophages successively adopt all four shapes as they migrate through ECM. Treatment with inhibitors of MMPs or Rac GTPase to abolish mesenchymal migration, suppresses both ECM degradation and HSPC mobilisation while differently affecting macrophage behaviour. This study depicts real time macrophage behaviour in a physiological context and reveals extreme reactivity of these cells constantly adapting and switching migratory shapes to achieve HSPCs proper mobilisation.

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Macrophage plasticity is Rac signalling and MMP9 dependant

10.1101/614388 ◽

2019 ◽

Author(s):

Jana Travnickova ◽

Sandra Nhim ◽

Naoill Abdellaoui ◽

Farida Djouad ◽

Maï Nguyen-Chi ◽

...

Keyword(s):

Extracellular Matrix ◽

Morphometric Analysis ◽

Zebrafish Embryo ◽

Tissue Remodelling ◽

Rac Gtpase ◽

Cell Shapes ◽

Ecm Degradation ◽

Macrophage Plasticity ◽

Ecm Architecture

AbstractIn vitro, depending on extracellular matrix (ECM) architecture, macrophages migrate either in amoeboid or mesenchymal mode; while the first is a general trait of leukocytes, the latter is associated with tissue remodelling via Matrix Metalloproteinases (MMPs). To assess whether these stereotyped migrations could be also observed in a physiological context, we used the zebrafish embryo and monitored macrophage morphology, behaviour and capacity to mobilisation haematopoietic stem/progenitor cells (HSPCs), as a final functional readout. Morphometric analysis identified 4 different cell shapes. Live imaging revealed that macrophages successively adopt all four shapes as they migrate through ECM. Treatment with inhibitors of MMPs or Rac GTPase to abolish mesenchymal migration, suppresses both ECM degradation and HSPC mobilisation while differently affecting macrophage behaviour. This study depicts real time macrophage behaviour in a physiological context and reveals extreme reactivity of these cells constantly adapting and switching migratory shapes to achieve HSPCs proper mobilisation.

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Extracellular matrix derived peptides and mesenchymal stem cell motility

10.26686/wgtn.17152088.v1 ◽

2021 ◽

Author(s):

◽

Sandi Grainne Dempsey

Keyword(s):

Extracellular Matrix ◽

Wound Healing ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Cell Motility ◽

Cell Attachment ◽

Mass Spectrometry Analysis ◽

And Migration ◽

Proliferation And Migration

<p>Biomaterials derived from decellularised extracellular matrices have shown promise as tools in tissue regeneration and wound healing. Such materials display biocompatibility as well as inherent bioactivity, promoting constructive remodelling in healing tissues. In this study, the bioactivity of ovine forestomach matrix (a decellularised extracellular matrix biomaterial) is assessed based on its ability to affect the proliferation and migration of wound healing cells. This material supported cell attachment and proliferation, but did not allow cell infiltration in vitro. Enzymatic digestion of the material rendered soluble components that were able to induce proliferation and migration of some cell types. Cell-mediated processing of the material generated a protein or proteins with chemotactic activity for mesenchymal stem cells in vitro. Mass spectrometry analysis indicated the bioactive component consisted of the proteoglycan decorin, or fragments thereof. Decorin has not previously been shown to induce mesenchymal stem cell motility, and these findings may add to what is known about decorin and its role in constructive remodelling. Furthermore, this cell-mediated approach for ECM breakdown could lead to the discovery of other bioactive peptides involved in ECM remodelling and wound healing.</p>

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Lysyl oxidase-like 2 is increased in asthma and contributes to asthmatic airway remodelling

European Respiratory Journal ◽

10.1183/13993003.04361-2020 ◽

2022 ◽

pp. 2004361

Author(s):

Jopeth Ramis ◽

Robert Middlewick ◽

Francesco Pappalardo ◽

Jennifer T. Cairns ◽

Iain D. Stewart ◽

...

Keyword(s):

Extracellular Matrix ◽

Lysyl Oxidase ◽

Airway Smooth Muscle Cells ◽

Airway Remodelling ◽

Collagen Deposition ◽

Tissue Remodelling ◽

Asthmatic Airway ◽

Bronchial Biopsies

Airway smooth muscle cells (ASM) are fundamental to asthma pathogenesis, influencing bronchoconstriction, airway hyper-responsiveness, and airway remodelling. Extracellular matrix (ECM) can influence tissue remodelling pathways, however, to date no study has investigated the effect of ASM ECM stiffness and crosslinking on the development of asthmatic airway remodelling. We hypothesised that TGFβ activation by ASM is influenced by ECM in asthma and sought to investigate the mechanisms involved. This study combines in vitro and in vivo approaches: human ASM cells were used in vitro to investigate basal TGFβ activation and expression of ECM crosslinking enzymes. Human bronchial biopsies from asthmatic and non-asthmatic donors were used to confirm LOXL2 expression ASM. A chronic ovalbumin model of asthma was used to study the effect of LOXL2 inhibition on airway remodelling. We found that ASM cells from asthmatics activated more TGFβ basally than non-asthmatic controls and that diseased cell-derived ECM influences levels of TGFβ activated. Our data demonstrate that the ECM crosslinking enzyme LOXL2 is increased in asthmatic ASM cells and in bronchial biopsies. Crucially, we show that LOXL2 inhibition reduces ECM stiffness and TGFβ activation in vitro, and can reduce subepithelial collagen deposition and ASM thickness, two features of airway remodelling, in an ovalbumin mouse model of asthma. These data are the first to highlight a role for LOXL2 in the development of asthmatic airway remodelling and suggest that LOXL2 inhibition warrants further investigation as a potential therapy to reduce remodelling of the airways in severe asthma.

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Extracellular matrix derived peptides and mesenchymal stem cell motility

10.26686/wgtn.17152088 ◽

2021 ◽

Author(s):

◽

Sandi Grainne Dempsey

Keyword(s):

Extracellular Matrix ◽

Wound Healing ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Cell Motility ◽

Cell Attachment ◽

Mass Spectrometry Analysis ◽

And Migration ◽

Proliferation And Migration

<p>Biomaterials derived from decellularised extracellular matrices have shown promise as tools in tissue regeneration and wound healing. Such materials display biocompatibility as well as inherent bioactivity, promoting constructive remodelling in healing tissues. In this study, the bioactivity of ovine forestomach matrix (a decellularised extracellular matrix biomaterial) is assessed based on its ability to affect the proliferation and migration of wound healing cells. This material supported cell attachment and proliferation, but did not allow cell infiltration in vitro. Enzymatic digestion of the material rendered soluble components that were able to induce proliferation and migration of some cell types. Cell-mediated processing of the material generated a protein or proteins with chemotactic activity for mesenchymal stem cells in vitro. Mass spectrometry analysis indicated the bioactive component consisted of the proteoglycan decorin, or fragments thereof. Decorin has not previously been shown to induce mesenchymal stem cell motility, and these findings may add to what is known about decorin and its role in constructive remodelling. Furthermore, this cell-mediated approach for ECM breakdown could lead to the discovery of other bioactive peptides involved in ECM remodelling and wound healing.</p>

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Graptopetalum paraguayense Inhibits Liver Fibrosis by Blocking TGF-β Signaling In Vivo and In Vitro

International Journal of Molecular Sciences ◽

10.3390/ijms20102592 ◽

2019 ◽

Vol 20 (10) ◽

pp. 2592 ◽

Cited By ~ 3

Author(s):

Wei-Hsiang Hsu ◽

Se-Chun Liao ◽

Yau-Jan Chyan ◽

Kai-Wen Huang ◽

Shih-Lan Hsu ◽

...

Keyword(s):

Extracellular Matrix ◽

Liver Fibrosis ◽

Liver Injury ◽

Rat Liver ◽

Injury Model ◽

Ethanol Extracts ◽

And Migration ◽

Tgf Β1

Background and Aims: Liver fibrosis is the excessive accumulation of extracellular matrix proteins, including collagen, which occurs in most types of chronic liver diseases. Advanced liver fibrosis results in cirrhosis, liver failure, and portal hypertension. Activated hepatic perivascular stellate cells, portal fibroblasts, and myofibroblasts of bone marrow origin have been identified as major collagen-producing cells in the injured liver. These cells are activated by fibrogenic cytokines, such as TGF-β1. The inhibition of TGF-β1 function or synthesis is a major target for the development of antifibrotic therapies. Our previous study showed that the water and ethanol extracts of Graptopetalum paraguayense (GP), a Chinese herbal medicine, can prevent dimethylnitrosamine (DMN)-induced hepatic inflammation and fibrosis in rats. Methods: We used rat hepatic stellate HSC-T6 cells and a diethylnitrosamine (DEN)-induced rat liver injury model to test the potential mechanism of GP extracts and its fraction, HH-F3. Results: We demonstrated that GP extracts and HH-F3 downregulated the expression levels of extracellular matrix (ECM) proteins and inhibited the proliferation and migration via suppression of the TGF-β1 pathway in rat hepatic stellate HSC-T6 cells. Moreover, the HH-F3 fraction decreased hepatic collagen content and reduced plasma AST, ALT, and γ-GT activities in a DEN-induced rat liver injury model, suggesting that GP/HH-F3 has hepatoprotective effects against DEN-induced liver fibrosis. Conclusion: These findings indicate that GP/HH-F3 may be a potential therapeutic agent for the treatment of liver fibrosis. The inhibition of TGF-β-mediated fibrogenesis may be a central mechanism by which GP/HH-F3 protects the liver from injury.

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Recreation of the terminal events in physiological integrin activation

The Journal of Cell Biology ◽

10.1083/jcb.200908045 ◽

2010 ◽

Vol 188 (1) ◽

pp. 157-173 ◽

Cited By ~ 186

Author(s):

Feng Ye ◽

Guiqing Hu ◽

Dianne Taylor ◽

Boris Ratnikov ◽

Andrey A. Bobkov ◽

...

Keyword(s):

Extracellular Matrix ◽

Cell Adhesion ◽

Integrin Signaling ◽

Integrin Activation ◽

Matrix Assembly ◽

Integrin Αiibβ3 ◽

Terminal Events ◽

Cell Adhesion And Migration ◽

And Migration

Increased affinity of integrins for the extracellular matrix (activation) regulates cell adhesion and migration, extracellular matrix assembly, and mechanotransduction. Major uncertainties concern the sufficiency of talin for activation, whether conformational change without clustering leads to activation, and whether mechanical force is required for molecular extension. Here, we reconstructed physiological integrin activation in vitro and used cellular, biochemical, biophysical, and ultrastructural analyses to show that talin binding is sufficient to activate integrin αIIbβ3. Furthermore, we synthesized nanodiscs, each bearing a single lipid-embedded integrin, and used them to show that talin activates unclustered integrins leading to molecular extension in the absence of force or other membrane proteins. Thus, we provide the first proof that talin binding is sufficient to activate and extend membrane-embedded integrin αIIbβ3, thereby resolving numerous controversies and enabling molecular analysis of reconstructed integrin signaling.

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Plasticity of the actin cytoskeleton in response to extracellular matrix nanostructure and dimensionality

Biochemical Society Transactions ◽

10.1042/bst20140139 ◽

2014 ◽

Vol 42 (5) ◽

pp. 1356-1366 ◽

Cited By ~ 14

Author(s):

Josefine Starke ◽

Bernhard Wehrle-Haller ◽

Peter Friedl

Keyword(s):

Extracellular Matrix ◽

Actin Cytoskeleton ◽

Shape Change ◽

Leading Edge ◽

High Speeds ◽

Efficient Induction ◽

Important Input ◽

Single Force ◽

And Migration

Mobile cells discriminate and adapt to mechanosensory input from extracellular matrix (ECM) topographies to undergo actin-based polarization, shape change and migration. We tested ‘cell-intrinsic’ and adaptive components of actin-based cell migration in response to widely used in vitro collagen-based substrates, including a continuous 2D surface, discontinuous fibril-based surfaces (2.5D) and fibril-based 3D geometries. Migrating B16F1 mouse melanoma cells expressing GFP–actin developed striking diversity and adaptation of cytoskeletal organization and migration efficacy in response to collagen organization. 2D geometry enabled keratinocyte-like cell spreading and lamellipod-driven motility, with barrier-free movement averaging the directional vectors from one or several leading edges. 3D fibrillar collagen imposed spindle-shaped polarity with a single cylindrical actin-rich leading edge and terminal filopod-like protrusions generating a single force vector. As a mixed phenotype, 2.5D environments prompted a broad but fractalized leading lamella, with multiple terminal filopod-like protrusions engaged with collagen fibrils to generate an average directional vector from multiple, often divergent, interactions. The migratory population reached >90% of the cells with high speeds for 2D, but only 10–30% of the cells and a 3-fold lower speed range for 2.5D and 3D substrates, suggesting substrate continuity as a major determinant of efficient induction and maintenance of migration. These findings implicate substrate geometry as an important input for plasticity and adaptation of the actin cytoskeleton to cope with varying ECM topography and highlight striking preference of moving cells for 2D continuous-shaped over more complex-shaped discontinuous 2.5 and 3D substrate geometries.

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ILB® resolves inflammatory scarring and promotes functional tissue repair

npj Regenerative Medicine ◽

10.1038/s41536-020-00110-2 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Lisa J. Hill ◽

Hannah F. Botfield ◽

Ghazala Begum ◽

Omar Qureshi ◽

Vasanthy Vigneswara ◽

...

Keyword(s):

Extracellular Matrix ◽

Tissue Repair ◽

Transforming Growth Factor ◽

Clinical Success ◽

Loss Of Function ◽

Tissue Remodelling ◽

Functional Tissue ◽

Fibrotic Diseases ◽

Matrix Dynamics

AbstractFibrotic disease is a major cause of mortality worldwide, with fibrosis arising from prolonged inflammation and aberrant extracellular matrix dynamics. Compromised cellular and tissue repair processes following injury, infection, metabolic dysfunction, autoimmune conditions and vascular diseases leave tissues susceptible to unresolved inflammation, fibrogenesis, loss of function and scarring. There has been limited clinical success with therapies for inflammatory and fibrotic diseases such that there remains a large unmet therapeutic need to restore normal tissue homoeostasis without detrimental side effects. We investigated the effects of a newly formulated low molecular weight dextran sulfate (LMW-DS), termed ILB®, to resolve inflammation and activate matrix remodelling in rodent and human disease models. We demonstrated modulation of the expression of multiple pro-inflammatory cytokines and chemokines in vitro together with scar resolution and improved matrix remodelling in vivo. Of particular relevance, we demonstrated that ILB® acts, in part, by downregulating transforming growth factor (TGF)β signalling genes and by altering gene expression relating to extracellular matrix dynamics, leading to tissue remodelling, reduced fibrosis and functional tissue regeneration. These observations indicate the potential of ILB® to alleviate fibrotic diseases.

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THAP1 modulates oligodendrocyte maturation by regulating ECM degradation in lysosomes

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2100862118 ◽

2021 ◽

Vol 118 (31) ◽

pp. e2100862118

Author(s):

Dhananjay Yellajoshyula ◽

Samuel S. Pappas ◽

Abigail E. Rogers ◽

Biswa Choudhury ◽

Xylena Reed ◽

...

Keyword(s):

Central Nervous System ◽

Extracellular Matrix ◽

Nervous System ◽

Oligodendrocyte Progenitor Cells ◽

Gene Encoding ◽

A Cell ◽

Ecm Degradation ◽

Oligodendrocyte Development

Mechanisms controlling myelination during central nervous system (CNS) maturation play a pivotal role in the development and refinement of CNS circuits. The transcription factor THAP1 is essential for timing the inception of myelination during CNS maturation through a cell-autonomous role in the oligodendrocyte lineage. Here, we demonstrate that THAP1 modulates the extracellular matrix (ECM) composition by regulating glycosaminoglycan (GAG) catabolism within oligodendrocyte progenitor cells (OPCs). Thap1−/− OPCs accumulate and secrete excess GAGs, inhibiting their maturation through an autoinhibitory mechanism. THAP1 controls GAG metabolism by binding to and regulating the GusB gene encoding β-glucuronidase, a GAG-catabolic lysosomal enzyme. Applying GAG-degrading enzymes or overexpressing β-glucuronidase rescues Thap1−/− OL maturation deficits in vitro and in vivo. Our studies establish lysosomal GAG catabolism within OPCs as a critical mechanism regulating oligodendrocyte development.

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