Biology subjects

Poincloux, R.

Publications and source records attributed to Poincloux, R..

18 recordsLinked to original sources

bioRxiv2026

Layered helical order reveals assembly states in podosome actin networks

How stochastic molecular events are converted into ordered cellular machines that perform mechanical work remains a central question in biology. Cryo-electron tomography enables visualization of macromolecular assemblies inside cells at molecular resolution, but static tomograms are generally interpreted as structural snapshots, with limited access to assembly state and temporal progression. Here, we show that cellular tomograms retain interpretable information about the assembly of a force-generating actin network. Using human macrophage podosomes as a physiologically relevant system, we combine spatial mapping of actin filaments (F-actin) and Arp2/3-mediated branch junctions, orientation analysis of deep-learning-based filament segmentations and Markov-chain modeling to infer actin-network assembly in situ. We identify favored membrane-directed actin polymerization and Arp2/3-mediated branching, establishing a local growth axis for podosome network organization. At the network scale, podosomes display layered helical order: filament-orientation classes recur at intervals of approximately 33 nm along the membrane-normal axis, forming a three-class cycle that returns to an approximately equivalent non-polar orientation. Markov modeling identifies preferred mother-to-daughter filament-orientation transitions and yields a stationary composition of branch-orientation states that closely matches that observed in structurally more advanced network regions. Together, these results link local actin nucleation, network-scale architecture and structural assembly state in a native cellular machine. Our study advances cryo-electron tomography from structural description toward temporal inference and 4D in situ structural biology.

cell biology↗

bioRxiv2025

Dual human lung models reveal compartment-specific activity of anti-tuberculosis drugs and host-directed therapies

Tuberculosis (TB) remains a major global health challenge that requires new therapeutic strategies to improve drug efficacy, shorten treatment duration, prevent drug resistance, and limit Mycobacterium tuberculosis (Mtb) persistence. Here, we established complementary in vitro human lung models integrating alveolar macrophage-like (AML) cells and airway air-liquid interface (ALI) cultures to evaluate standard-of-care antibiotics, host-directed therapies, and virulence-targeting agents. AMLs recapitulated key morphological, transcriptional, and functional features of primary alveolar macrophages, including a CD16+ immunoregulatory phenotype highly permissive to Mtb infection. In parallel, ALI cultures maintained epithelial barrier integrity and secretory functions, allowing apical Mtb infection, drug penetration analysis, and inflammatory profiling. Benchmarking of standard-of-care antibiotics revealed compartment-specific activity: isoniazid, rifampicin, and moxifloxacin were effective in both systems, while pyrazinamide was active only in AMLs. Anti-inflammatory host-directed therapies such as ibuprofen and doramapimod selectively reduced cytokine production without affecting bacterial load. Together, this dual-platform system offers a physiologically relevant and scalable model to assess antimicrobial efficacy and host modulation across distinct pulmonary niches, bridging the gap between conventional macrophage assays and the complex human lung.

immunology↗

bioRxiv2025

4polar3D : Single molecule 3D orientation imaging of dense actin networks using ratiometric polarization splitting

Single Molecule Orientation and Localization Microscopy (SMOLM) aims at simultaneously measuring the position and orientation of single molecules, generating orientation-encoded super-resolved images by estimating both their 3D mean orientation and the extent of their angular fluctuations (wobble). Most existing SMOLM approaches rely on the engineering of single molecules point spread functions, which requires complex optical setups and long computational times that can be an obstacle in dense cellular environments with high detection density and challenging imaging conditions. In this work, we propose a simpler and effective method named 4polar3D, based on the estimation of single molecule intensities projected onto four polarized channels with controlled numerical apertures. This strategy enables 3D orientation measurements of single molecules in addition to their 2D localization in a fast processing step. We demonstrate that 4polar3D can resolve nanoscale molecular organization in whole cells crowded structures, uncovering 3D-oriented actin filament networks in densely packed lamellipodia and podosomes.

bioengineering↗

bioRxiv2025

Myo1e/f at the podosome base regulate podosome dynamics and promote macrophage migration

Cells of the monocyte lineage form specialized membrane-associated, actin-rich structures, called podosomes. Podosomes play important roles in cell adhesion and migration as well as the proteolytic degradation of the extracellular matrix. While podosomes are always closely associated with the plasma membrane, the structural components linking the podosome core, composed of branched actin, to the membrane are not fully understood. In this study we show that class I myosins, Myo1e and Myo1f, localize to a specific region of podosomes, underneath the podosome core and near the ventral plasma membrane, and that this localization is mainly mediated by the Myo1e/f TH2 domains. Respective knockdowns or knockouts of Myo1e/f lead to increased podosome size, altered turnover and lateral mobility, which is likely due to Myo1e/f regulating the attachment of core actin filaments to the plasma membrane. In addition, Myo1e/f double knockout macrophages were characterized by a reduction in 3D and 2D migration, even though these cells exhibited increased ability to degrade the extracellular matrix. Along with the other membrane-associated podosome components, such as the transmembrane proteins MT-MMP and CD44, and the GPI-anchored DNase X, Myo1e and Myo1f mark the membrane-proximal region of podosomes. We propose to label this region as the podosome "base", an additional substructure joining the current trifecta of the podosome cap, core, and ring.

cell biology↗

bioRxiv2025

Identification of a unique TUBB3+ cell population in the tuberculosis granuloma

Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains a leading cause of mortality worldwide. Granulomas, hallmark structures of TB in the lungs and other infected tissues, are critical sites of host-pathogen interactions, yet their full cellular composition is not completely understood. Here, we identify a previously unrecognized {beta}3-tubulin (TUBB3)-positive cell population within TB granulomas in mice, guinea pigs, non-human primates, and TB patients. TUBB3 is a well-established pan-neuronal marker, yet these TUBB3+ cells are distinct from typical pulmonary resident cells and leukocytes. They exhibit a branched, elongated morphology, which is suggestive of neuron-like features. Intriguingly, their appearance is independent of adaptive immunity and is also observed in viral and fungal infections, but not in asthma. Our findings suggest the existence of a neuro-immune component within granulomas that may influence TB pathogenesis. Further investigation into the origin, function, and signaling pathways of these TUBB3+ cells is required to clarify their identity and potential role in host defense, which could reveal novel therapeutic targets for TB and other pulmonary infections.

immunology↗

bioRxiv2025

Capsule-mediated O-antigen masking protects hypervirulent Klebsiella pneumoniae from neutrophil killing

Klebsiella pneumoniae is listed as a critical priority pathogen by the WHO due to prevalent extended-spectrum {beta}-lactamase and carbapenem resistance and high mortality rates Hypervirulent K. pneumoniae (hvKp) causes life-threatening infections in immunocompetent individuals, while classical K. pneumoniae (cKp) causes nosocomial infections in immunosuppressed patients. The convergence of hypervirulence with antibiotic resistance is now a major global health threat. Using a murine pulmonary infection model, we show that hvKp resisted clearance despite significant neutrophil recruitment. Using clinical hvKp and cKp isolates, bone marrow derived neutrophils, cell biology, pharmacology and imaging (both light and electron microscopy) in ex vivo assays revealed that the hvKp hypermucoviscous capsule prevents bacterial recognition and neutrophil activation, blocking ROS production, degranulation, and neutrophil extracellular traps (NETs) formation. In the absence of capsule ({Delta}wcaJ) or hypermucoid capsule determinants ({Delta}rmpADC), hvKp activates neutrophils, leading to degranulation, NET formation and bacterial killing. While superimposing the absence of O-antigen ({Delta}rfb) on the {Delta}wcaJ abrogates degranulation, neutrophils still elaborate NETs that eliminate the {Delta}wcaJ/{Delta}rfb mutant at high efficiency. This suggests that O-antigen is a double-edged sword, functioning as a PAMP triggering neutrophil degranulation yet assisting the pathogen to evade NET-mediated destruction. These findings shed light on the mechanism underpinning immune evasion by the hypervirulent capsule in hvKp.

microbiology↗

bioRxiv2024

Megakaryocytes build a cage of extracellular matrix that controls their maturation and anchoring to the vascular niche

Megakaryocytes, the progenitor cells of blood platelets, play a crucial role in hemostasis by residing in the bone marrow and ensuring continuous platelet production. Unlike other hematopoietic cells, megakaryocytes do not enter the blood circulation intact. They remain anchored within the bone marrow while extending cytoplasmic protrusions called proplatelets through the sinusoidal endothelial barrier. These proplatelets subsequently fragment into functional platelets. This unique process of intravasation facilitates efficient platelet production while maintaining the megakaryocyte cell body within the bone marrow niche, thus preventing potential thrombotic complications. How the extracellular matrix (ECM) influences the delicate balance between megakaryocyte retention and proplatelet extension remains largely unknown. Here, we investigate the spatial organization and functional role of ECM components in the megakaryocyte vascular niche. Our findings reveal that laminin and collagen IV form three-dimensional (3D) ECM cages encompassing megakaryocytes and anchor them to the sinusoidal basement membrane. Gene deletion shows the existence of laminin 4 in the ECM cage that is necessary to maintain megakaryocyte-sinusoid interactions. Notably, megakaryocytes actively contribute to the ECM cage assembly; {beta}1/{beta}3 integrin knockout weakens these structures, increasing intravasation and entire megakaryocyte entry into circulation. The retention of megakaryocytes by these 3D ECM cages depends on dynamic remodeling processes. Inhibition of ECM proteolysis results in denser cage formation, increasing the frequence of immature megakaryocytes with impaired demarcation membrane system (DMS) development. Thus, the ECM cage represents a novel concept of an active and dynamic 3D microenvironment that is continuously remodeled and essential for maintaining megakaryocyte perivascular positioning. This specific microarchitecture guides megakaryocyte maturation and intravasation, underscoring the critical role of ECM microarchitecture and dynamics in megakaryocyte function. Key PointsO_LIMegakaryocytes form a three-dimensional (3D) cage composed of laminin and collagen IV connected to the basement membrane surrounding them. This microarchitecture stabilizes megakaryocytes within their vascular niche. C_LIO_LI{beta}1/{beta}3 integrins and MMP are key ECM cage regulators that assist megakaryocyte maturation and intravasation at the bone marrow-blood interface. C_LI

physiology↗

bioRxiv2024

Inhibition of glycolysis in tuberculosis-mediated metabolic rewiring reduces HIV-1 spread across macrophages

Tuberculosis (TB) is a significant aggravating factor in individuals living with human immunodeficiency virus type 1 (HIV-1), the causative agent for acquired immunodeficiency syndrome (AIDS). Both Mycobacterium tuberculosis (Mtb), the bacterium responsible for TB, and HIV-1 target macrophages. Understanding how Mtb subverts these cells may facilitate the identification of new druggable targets. Here, we explored how TB can induce macrophages to form tunneling nanotubes (TNT), promoting HIV-1 spread. We found that TB triggers metabolic rewiring of macrophages, increasing their glycolytic ATP production. Using pharmacological inhibitors and glucose deprivation, we discovered that disrupting aerobic glycolysis significantly reduces HIV-1 exacerbation in these macrophages. Glycolysis is essential for tunneling nanotubes (TNT) formation, which facilitates viral transfer and cell-to-cell fusion and induces the expression of the sialoadhesin Siglec-1, enhancing both HIV-1 binding and TNT stabilization. Glycolysis did not exacerbate HIV-1 infection when TNT formation was pharmacologically prevented, indicating that higher metabolic activity is not sufficient per se to make macrophages more susceptible to HIV-1. Overall, these data might facilitate the development of targeted therapies aimed at inhibiting glycolytic activity in TB-induced immunomodulatory macrophages to ultimately halt HIV-1 dissemination in co-infected patients.

immunology↗

bioRxiv2024

Moesin activation controls bone resorption and tunneling nanotube-dependent osteoclast fusion

Cell-cell fusion is an evolutionarily conserved process that is essential for many functions, including fertilisation and the formation of placenta, muscle and osteoclasts, multinucleated cells that are unique in their ability to resorb bone. The mechanisms of osteoclast multinucleation involve dynamic interactions between the actin cytoskeleton and the plasma membrane that are still poorly characterized. Here, we found that moesin, a cytoskeletal linker protein member of the Ezrin/Radixin/Moesin (ERM) protein family, is activated during osteoclast maturation and plays an instrumental role in both osteoclast fusion and function. In mouse and human osteoclast precursors, moesin inhibition favors their ability to fuse into multinucleated osteoclasts. Accordingly, we demonstrated that moesin depletion decreases membrane-to-cortex attachment and enhances the formation of tunneling nanotubes (TNTs), F-actin-based intercellular bridges that we reveal here to trigger cell-cell fusion. Moesin also controls HIV-1- and inflammation-induced cell fusion. In addition, moesin regulates the formation of the sealing zone, the adhesive structure determining osteoclast bone resorption area, and thus controls bone degradation, via a {beta}3-integrin/RhoA/SLK pathway. Supporting our results, moesin-deficient mice present a reduced density of trabecular bones and increased osteoclast abundance and activity. These findings provide a better understanding of the regulation of cell-cell fusion and osteoclast biology, opening new opportunities to specifically target osteoclast activity in bone disease therapy.

cell biology↗

bioRxiv2023

The membrane-actin linkers ezrin, radixin, and moesin are dispensable for macrophage migration and cortex mechanics.

The cellular actin cortex provides crucial mechanical support and plays critical roles in numerous functions, including cell division and migration. The proteins of the ERM family, ezrin, radixin, and moesin, are central to these processes by linking the plasma membrane to the actin cytoskeleton. To investigate the individual contributions of these three proteins to leukocyte migration, we generated single and triple ERM knock-out macrophages. Surprisingly, we found that even in the absence of ERMs, macrophages can still form the different actin structures promoting cell migration, such as filopodia, lamellipodia, podosomes, and ruffles. Furthermore we discovered that, unlike every other cell type previously investigated, the single or triple knock-out of ERMs does not affect macrophage migration in a large diversity of contexts. Finally, we demonstrated that the loss of ERMs in macrophages does not affect the mechanics of their actin cortex. These findings challenge the notion that ERMs are universally essential for cortex mechanics and cell migration and support the notion that the macrophage cortex may have diverged from that of other cells to allow for their adaptive cortical plasticity.

cell biology↗

bioRxiv2023

Specialized actin nanoscale layers control focal adhesion turnover

Focal adhesions (FAs) connect inner workings of the cell to the extracellular matrix to control cell adhesion, migration, and mechanosensing1,2. Previous studies demonstrated that FAs contain three vertical layers, which connect extracellular matrix to the cytoskeleton3,4,5. However, cellular processes rely on precisely-regulated FA turnover, but the molecular machineries that control FA assembly and disassembly have remained elusive. By using super-resolution iPALM microscopy, we identified two unprecedented nanoscale layers within FAs, specified by actin filaments bound to tropomyosin isoforms Tpm1.6 and Tpm3.2. The Tpm1.6-actin filaments beneath the previously identified actin-regulatory layer are critical for adhesion maturation and controlled cell motility, whereas the Tpm3.2-actin filament layer towards the bottom of FA facilitates adhesion disassembly. Mechanistically, Tpm3.2 stabilizes KANK-family proteins at adhesions, and hence targets microtubule plus-ends to FAs to catalyse their disassembly. Loss of Tpm3.2 leads to disorganized microtubule network, abnormally stable FAs, and defects in tail retraction during cell migration. Thus, FAs are composed of at least three distinct actin filament layers, each having specific roles in coupling of adhesion to the cytoskeleton, or in controlling adhesion dynamics. In a broader context, these findings demonstrate how distinct actin filament populations can co-exist and perform specific functions within a defined cellular compartment.

cell biology↗

bioRxiv2021

Nanoscale architecture and coordination of actin cores within the sealing zone of human osteoclasts

Osteoclasts are unique in their capacity to degrade bone tissue. To achieve this process, osteoclasts form a specific structure called the sealing zone, which creates a close contact with bone and confines the release of protons and hydrolases for bone degradation. The sealing zone is composed of actin structures called podosomes nested in a dense actin network. The organization of these actin structures inside the sealing zone at the nano scale is still unknown. Here, we combine cutting-edge microscopy methods to reveal the nanoscale architecture and dynamics of the sealing zone formed by human osteoclasts on bone surface. Random illumination microscopy allowed the identification and live imaging of densely packed actin cores within the sealing zone. A cross-correlation analysis of the fluctuations of actin content at these cores indicates that they are locally synchronized. Further examination shows that the sealing zone is composed of groups of synchronized cores linked by -actinin1 positive filaments, and encircled by adhesion complexes. Thus, we propose that the confinement of bone degradation mediators is achieved through the coordination of islets of actin cores and not by the global coordination of all podosomal subunits forming the sealing zone.

cell biology↗

bioRxiv2021

Pseudomonas aeruginosa infection reveals a Caspase-1-dependent neutrophil pyroptosis pathway that restrains damaging Histone release

Multiple neutrophil death programs contribute to host defense against infections. Although expressing all necessary components, neutrophils specifically fail to undergo pyroptosis, a lytic form of cell death triggered by the activation of the pro-inflammatory complex inflammasome. In the light of the arm race, we hypothesized that intrinsic neutrophil pyroptosis resistance might be bypassed in response to specific microbial species. We show that Pseudomonas aeruginosa (P. aeruginosa) stimulates Caspase-1-dependent pyroptosis in human and murine neutrophils. Mechanistically, activated NLRC4 inflammasome supports Caspase-1-driven Gasdermin-D (GSDMD) activation, IL-1{beta} cytokine release and neutrophil pyroptosis. Furthermore, GSDMD activates Peptidyl Arginine Deaminase-4 which drives an "incomplete NETosis" where neutrophil DNA fills the cell cytosol but fails crossing plasma membrane. Finally, we show that neutrophil Caspase-1 account for IL-1{beta} production and contributes to various P. aeruginosa strains spread in mice. Overall, we demonstrate that neutrophils are fully competent for Caspase-1-dependent pyroptosis, which drives an unsuspected "incomplete NETosis". SummaryNeutrophils play an essential roles against infections. Although multiple neutrophil death programs contribute to host defense against infections, they fail to undergo pyroptosis, a pro-inflammatory form of cell death. Upon Infections, pyroptosis can be induced in macrophages or epithelial cells upon activation of pro-inflammatory complexes, inflammasomes that trigger Caspase-1-driven Gasdermin dependent plasma membrane lysis. In the light of host-microbe interactions, we hypothesized that yet to find microbial species might hold the capacity to overcome neutrophil resistance to inflammasome-driven pyroptosis. Among several bacterial species, we describe that the bacterium Pseudomonas aeruginosa specifically engages the NLRC4 inflammasome, which promotes Caspase-1-dependent Gasdermin-D activation and subsequent neutrophil pyroptosis. Furthermore, inflammasome-driven pyroptosis leads to DNA decondensation and expansion into the host cell cytosol but not to the so called Neutrophil Extracellular Trap (NET) release as DNA fails breaching the plasma membrane. Finally, in vivo P. aeruginosa infections highlight that Caspase-1-driven neutrophil pyroptosis is functional and is detrimental upon P. aeruginosa infection. Altogether, our results unexpectedly underline neutrophil competence for Caspase-1-dependent pyroptosis, a process that contributes to host susceptibility to P. aeruginosa infection.

immunology↗

bioRxiv2021

Elasticity of dense actin networks produces nanonewton protrusive forces

Actin filaments assemble into force-generating systems involved in diverse cellular functions, including cell motility, adhesion, contractility and division. It remains unclear how networks of actin filaments, which individually generate piconewton forces, can produce forces reaching tens of nanonewtons. Here we use in situ cryo-electron tomography to unveil how the nanoscale architecture of macrophage podosomes enables basal membrane protrusion. We show that the sum of the actin polymerization forces at the membrane is not sufficient to explain podosome protrusive forces. Quantitative analysis of podosome organization demonstrates that the core is composed of a dense network of bent actin filaments storing elastic energy. Theoretical modelling of the network as a spring-loaded elastic material reveals that it exerts forces of up to tens of nanonewtons, similar to those evaluated experimentally. Thus, taking into account not only the interface with the membrane but also the bulk of the network, is crucial to understand force generation by actin machineries. Our integrative approach sheds light on the elastic behavior of dense actin networks and opens new avenues to understand force production inside cells.

biophysics↗

bioRxiv2020

HIV-1-infected human macrophages, by secreting RANKL, contribute to enhanced osteoclastogenesis

HIV-1 infection is frequently associated with low bone density, which can progress to osteoporosis leading to a high risk of fractures. Only a few mechanisms have been proposed to explain the enhanced osteolysis in the context of HIV-1 infection. As macrophages are involved in bone homeostasis and are critical cell hosts for HIV-1, we asked whether HIV-1-infected macrophages could participate in bone degradation. Upon infection, human macrophages acquired some osteoclast features: they became multinucleated, upregulated the osteoclast markers RhoE and {beta}3 integrin, and organized their podosomes as ring superstructures resembling osteoclast sealing zones. However, HIV-1 infected macrophages were not fully differentiated in osteoclasts as they did not upregulate NFATc-1 transcription factor and were unable to degrade bone. Investigating whether infected macrophages participate indirectly to virus-induced osteolysis, we showed that they produce RANKL, the key osteoclastogenic cytokine. RANK-L secreted by HIV-1-infected macrophages was not sufficient to stimulate multinucleation, but promoted the protease-dependent migration of osteoclast precursors. In conclusion, we propose that, by stimulating RANKL secretion, HIV-1-infected macrophages contribute to create a microenvironment that favors the recruitment of osteoclasts, participating to bone disorders observed in HIV-1+ patients.

cell biology↗

bioRxiv2020

Super-resolved live-cell imaging using Random Illumination Microscopy

Super-resolution fluorescence microscopy has been instrumental to progress in biology. Yet, the photo-induced toxicity, the loss of resolution into scattering samples or the complexity of the experimental setups curtail its general use for functional cell imaging. Here, we describe a new technology for tissue imaging reaching a 114nm/8Hz resolution at 30 {micro}m depth. Random Illumination Microscopy (RIM) consists in shining the sample with uncontrolled speckles and extracting a high-fidelity super-resolved image from the variance of the data using a reconstruction scheme accounting for the spatial correlation of the illuminations. Super-resolution unaffected by optical aberrations, undetectable phototoxicity, fast image acquisition rate and ease of use, altogether, make RIM ideally suited for functional live cell imaging in situ. RIM ability to image molecular and cellular processes in three dimensions and at high resolution is demonstrated in a wide range of biological situations such as the motion of Myosin II minifilaments in Drosophila.

bioengineering↗

bioRxiv2019

Tuberculosis-associated IFN-I induces Siglec-1 on tunneling nanotubes and favors HIV-1 spread in macrophages

While tuberculosis (TB) is a risk factor in HIV-1-infected individuals, the mechanisms by which Mycobacterium tuberculosis worsens HIV-1 pathogenesis remain poorly understood. Recently, we showed that HIV-1 infection and spread are exacerbated in macrophages exposed to TB-associated microenvironments due to tunneling nanotube (TNT) formation. To identify molecular factors associated with TNT function, we performed a transcriptomic analysis in these macrophages, and revealed the up-regulation of the lectin receptor Siglec-1. We demonstrate Siglec-1 expression depends on TB-mediated production of type I interferon. In co-infected non-human primates, Siglec-1 is highly expressed by alveolar macrophages, whose abundance correlates with pathology and activation of the type I interferon/STAT1 pathway. Intriguingly, Siglec-1 expression localizes exclusively on microtubule-containing TNT that are long and carry HIV-1 cargo. Siglec-1 depletion in macrophages decreases TNT length, diminishes HIV-1 capture and cell-to-cell transfer, and abrogates TB-driven exacerbation of HIV-1 infection. Altogether, we uncover a deleterious role for Siglec-1 in TB-HIV-1 co-infection, and its localization on TNT opens new avenues to understand cell-to-cell viral spread.

cell biology↗

bioRxiv2019

Genetic engineering of hoxb8 immortalized hematopoietic progenitors: a potent tool to study macrophage tissue migration

Tumor-associated macrophages (TAM) are detrimental in most cancers. Controlling their recruitment is thus potentially therapeutic. We showed that TAM perform the protease-dependent mesenchymal migration in cancer, while macrophages perform amoeboid migration in other tissues. Inhibition of mesenchymal migration correlates with decreased TAM infiltration and tumor growth, providing rationale for a new cancer immunotherapy specifically targeting TAM motility. To identify new effectors of mesenchymal migration, we produced ER-Hoxb8-immortalized hematopoietic progenitors with unlimited proliferative ability. The functionality of macrophages differentiated from ER-Hoxb8 progenitors was compared to bone marrow-derived macrophages (BMDM). They polarized into M1- and M2-orientated macrophages, generated ROS, ingested particles, formed podosomes, degraded the extracellular matrix, adopted amoeboid and mesenchymal migration in 3D, and infiltrated tumor explants ex vivo using mesenchymal migration. We also used the CRISPR/Cas9 system to disrupt gene expression of a known effector of mesenchymal migration, WASP, to provide a proof of concept. We observed impaired podosome formation and mesenchymal migration capacity, thus recapitulating the phenotype of BMDM isolated from Wasp-KO mice. Thus, we validate the use of Hoxb8-macrophages as a potent tool to investigate macrophage functionalities.\n\nSummary statementWe validate the use of ER-Hoxb8-immortalized hematopoietic progenitors combined to CRISPR/Cas9 technology as a potent tool to investigate macrophage functionalities with a large scale of applications.

cell biology↗