Neutrophils : the short lived cells

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Table of contents

0.1 Abstract
0.2 Foreword
1 Migration: a multiscale process
1.1 Migration: a multiscales process
1.2 Cell migration
1.2.1 Cell migration in health and disease
1.2.1.1 Cell migration during embryogenesis
1.2.1.1.1 Neural crest cells migration:
1.2.1.2 Cell migration to maintain tissue homeostasis
1.2.1.2.1 Cell migration during wound healing
1.2.1.3 Metastasis formation: when cell migration goes out of control
1.2.1.3.1 Some history
1.2.1.3.2 Cancer cell migration
2 Cell migration in the context of the immune response
2.1 Introduction to the immune system
2.1.0.4 Some history
2.2 The immune system
2.2.1 Innate immunity
2.2.2 Motiles cells in innate immunity
2.2.2.1 Macrophages: the long lived cells
2.2.2.2 Neutrophils: the short lived cells
2.2.2.3 The natural killers cells
2.2.2.4 Dendritic cells at the interface between innate and adaptive immunity
2.2.3 Adaptive immunity
2.2.3.1 The T lymphocytes
2.2.3.2 The B lymphocytes
2.2.3.3 Generation of memory
2.3 Dendritic cells
2.3.1 Antigen uptake in dendritic cells
2.3.2 From an immature to a mature state
2.3.3 Dendritic cells migratory routes
3 The physics of cell migration
3.1 Cell mechanics in migration
3.1.1 The cytoskeleton as a load bearing structure
3.1.1.1 The actin cytoskeleton
3.1.1.1.1 Actin polymerization
3.1.1.1.1.1 Arp2/3 based actin networks
3.1.1.1.1.2 Formins based actin networks
3.1.1.2 Actin networks and their mechanical properties
3.1.1.2.1 Actin networks mechanical properties
3.1.1.2.2 Mechanical properties of dendritic actin network
3.1.1.2.3 Mechanical properties of unbranched actin network
3.1.1.2.4 Force production by actin networks
3.1.1.2.4.1 Contractile forces
3.1.1.2.4.2 Protrusive forces
3.1.1.2.4.3 An exemple of actin based motility: actin comet tails
3.1.1.3 The microtubule network
3.1.1.3.1 Crosstalk between microtubules and actin
3.1.1.4 The intermediate filaments
3.1.2 Proposed model of the cytoplasm
3.1.3 Contribution of the plasma membrane to the cell mechanics
3.1.4 The nucleus in cell mechanics
3.2 Physical properties of the extracellular environment
3.2.1 in vivo environments
3.2.2 In vitro assays for mimicking in vivo environments
3.2.2.1 The 2D migration assay
3.2.2.2 3D collagen gels
3.2.2.3 1D/3D migration assays
3.3 Mechanotransduction in cell migration
3.3.1 Ions channels in mechanotransduction
3.3.1.0.1 Role of membrane potential in cell migration
3.3.1.0.2 Role of cell volume in cell migration
3.3.1.0.3 Calcium signalling in cell migration
3.3.1.0.4 pH in cell migration
3.4 Mechanism of cell migration
3.4.1 2D/planar migration
3.4.1.1 Adhesion dynamics
3.4.1.2 The molecular clutch model
3.4.2 3D cell migration
3.4.2.1 3D mesenchymal migration
3.4.2.2 3D amoeboid migration
3.4.2.2.1 Mechanism of blebbing migration
3.4.2.2.1.1 Myosin II as force generator
3.4.2.2.1.2 Models for force transmission in blebbing motility
3.4.2.2.2 Polymerization driven amoeboid migration
3.4.2.3 Switching migration mode as function of the ECM physical and chemical properties
3.4.3 1D-3D cell migration
3.4.3.1 Actin slab at the leading edge of neutrophils undergoing interstitial migration
3.4.3.2 Pushing on the walls to move forward
3.4.3.3 Interstitial migration independent of the actomyosin system: the osmotic engine model
4 Nuclear mechanics in cell migration
4.1 Nuclear mechanics
4.1.1 The nucleoplasm define the nuclear rheological properties
4.1.2 Mechanical properties of the lamina network
4.1.2.1 Structure of the lamina network
4.1.2.2 Lamina mechanics
4.2 Linking the nucleus to the cytoplasm
4.2.1 The LINC Complex
4.2.1.1 The SUN-domain proteins
4.2.1.2 The Kash-domain proteins
4.3 Nuclear mechanics in health and disease
4.3.1 Laminopathies
4.3.1.1 The structural hypothesis
4.3.1.2 The genome regulation hypothesis
4.4 The nucleus during cell migration
4.4.1 Nuclear positioning
4.4.1.1 Microtubules based nuclear positioning
4.4.1.2 Actin based nuclear positioning
4.4.1.2.1 The Transmembrane Actin-associated Nuclear (TAN) lines
4.4.2 The nucleus in mechanotransduction
4.4.2.1 Can the nucleus feel the force?
4.4.2.1.1 The actin caps
4.4.2.2 How could the nucleus react to forces?
4.4.3 The nucleus as limiting factor for cell migration
5 Objectives
6 Methods
6.1 Cellular models for cell migration
6.1.1 Dendritic cells as model system
6.1.1.0.1 Dendritic cells maturation
6.1.1.0.2 Genetic manipulation of dendritic cells
6.1.2 Neutrophils as a second model
6.2 Microchannels as an original setup for transmigration
6.2.1 The common setup: transwells
6.2.2 The microfabrication based setup: microchannels with constrictions
6.2.2.1 From soft photolithography to PDMS chambers
6.2.2.2 3D visualization of the channels geometry
6.2.2.2.1 Optical profilometer
6.2.2.2.2 Confocal imaging based channels measurement
6.3 Live cell imaging of cells migrating through constrictions
6.3.1 Channels preparation
6.3.2 Putting cells in channels
6.3.3 Video microscopy of cells crawling through constrictions
6.4 Immunostaining in microchannels
7 Results
7.1 An Arp2/3 based nuclear squeezing allows dendritic cells to passage through micrometric
constrictions
7.1.1 Summary
7.2 Manuscript in preparation for submission
7.2.1 Main text
7.2.2 Remarks
7.2.2.1 Analysis to perform
7.2.2.2 Experiments planed before submission
7.2.2.3 More general remarks
8 Discussion
8.1 An Arp2/3 based nuclear squeezing mechanism allows immature dendritic cells to pass through narrow gaps
8.2 The nucleus as a limiting factor for dendritic cells migration
8.2.1 A microchannel based set up
8.2.2 The nucleus limits migration below 12 m2 constrictions
8.3 Mechanisms of perinuclear actin meshwork formation
8.3.1 A retrograde flow based actin increase
8.3.2 Adhesion based actin formation
8.3.3 Microtubules based F-actin recruitment
8.3.4 Arp2/3 based nucleation
8.3.4.1 Arp2/3 recruitment at the nucleus
8.3.4.2 NPFs confinement induced Arp2/3 activation
8.3.5 Conclusion
8.4 Role of the actin accumulation in nuclear passage through constrictions
8.4.1 Breaking the Lamina network to allow nuclear passage through narrow pores
8.4.2 Phosphorilation based nuclear passage through constrictions
8.4.3 How are forces transmitted to the nucleus
8.4.4 Conclusion on the role of the perinuclear actin meshwork in constrictions
8.5 Role of myosin II in nuclear squeezing
8.6 Squeezing the nucleus through a small pore
8.6.1 Our model of nuclear squeezing during cell migration
8.6.2 Limits of this model
8.7 Perspectives
8.7.1 An intriguing Arp2/3 based nuclear squeezing
8.7.2 Cell survival during migration: role of the LINC complex
8.7.3 Importance of nuclear squeezing for in vivo cell migration
9 Conclusion
Bibliography