Special Issue: Cell Biology of the Immune System
CELL SCIENTISTS TO WATCH
CELL SCIENCE AT A GLANCE
Summary: A discussion of the distinct host cell transport routes that underpin the biogenesis and function of plant–pathogen interfaces.
Summary: Why is membrane trafficking rate-limiting for release of constitutively secreted interleukin-6? We propose that cells monitor and adjust cytokine secretion rates for prevention of septic shock.
Summary: This Review explores the forces driving the process of neutrophil extracellular trap (NET) formation, with a focus on the biophysical aspects.
Summary: Bone marrow adipocytes share a spatially constricted area with hematopoietic cells, and may act as intermediaries in communicating environmental signals that influence hematopoietic lineage decisions.
Summary: This Review provides a current perspective on live-cell imaging in vitro and in vivo with a focus on the understanding of the immune system at the subcellular and molecular level.
Molecular regulation of the plasma membrane-proximal cellular steps involved in NK cell cytolytic function
Summary: This review highlights the molecular steps involved in the regulation of lytic granule secretion by natural killer cells.
Summary: This manuscript provides a comprehensive review on canonical and regulatory adaptors for Toll-like receptors.
Macrophages show higher levels of engulfment after disruption of cis interactions between CD47 and the checkpoint receptor SIRPα
Summary: When a membrane receptor and its membrane ligand are on the same cell, they might interact in cis and modulate trans functions, as shown here for macrophage SIRPα and CD47.
Summary: The emerging idea that the cytoskeletal and biophysical principles are preserved in primary cells and transformed cell lines, and the two can be used to interchangeably examine synaptic actin characteristics, needs careful reconsideration.
Vav2 lacks Ca2+ entry-promoting scaffolding functions unique to Vav1 and inhibits T cell activation via Cdc42
Summary: The proto-oncoproteins Vav1 and Vav2 regulate immune function. Here, we identify key differences in catalytic specificity and scaffolding function that mediate their divergent impacts on T cell activation.
Identification of serine residues in the connexin43 carboxyl tail important for BCR-mediated spreading of B-lymphocytes
Summary: Mutation of specific serine residues of connexin43 affects B-cell spreading, suggesting that this protein can be considered as a regulator of B-cell responses.
Cofilin1-driven actin dynamics controls migration of thymocytes and is essential for positive selection in the thymus
Summary: Cofilin1 controlled migration determines the dwelling time of thymocytes in the thymic niches and is essential for positive selection and differentiation into mature CD4 and CD8 single-positive cells.
P2X7 receptor activation increases expression of caveolin-1 and formation of macrophage lipid rafts, thereby boosting CD39 activity
Summary: P2X7 receptor activation triggers the initiation of lipid raft-dependent regulatory pathways that upregulate CD39 activity, contributing to limit macrophage responses and inflammation.
Ca2+-activated cleavage of ezrin visualised dynamically in living myeloid cells during cell surface area expansion
Summary: The cleavage of ezrin, visualised in living cells by the separation of ezrin fluorescently labelled at the N- and C-termini, accompanies Ca2+-induced cell surface expansion.
Summary: A fluorescent reporter mouse for visualising F-actin structure and dynamics in live cells also reports T cell activation through a translationallly controlled mechanism.
Reactive oxygen species-mediated cytoplasmic stiffening impairs the phagocytic ability of the macrophage
Summary: Here, we explore how the deformability of macrophages impact their phagocytic ability and report a ROS-dependent cytoplasmic stiffening that reduces their phagocytic ability.
Summary: The anti-fungal innate immunoreceptor Dectin-1 induces signaling through RHOA, leading to contractile mechanical force generation necessary for phagocytosis.
Adhesion, motility and matrix-degrading gene expression changes in CSF-1-induced mouse macrophage differentiation
Summary: Widespread and profound changes occur in the expression of adhesion, motility and matrix-degrading genes as macrophages differentiate under the influence of CSF-1; the roles of paxillin and leupaxin adhesion proteins are compared.
Summary: Myo1e participates in the adhesion and migration of activated B cells at high endothelial venules by regulating integrins and the PI3K–FAK–RAC-1 signaling pathway.
Summary: Protein tyrosine phosphatase ε regulates the leukotriene D4-mediated responses of human monocytes and macrophages through modulation of ROCK2 phosphorylation.
Summary: Inhibition of SHIP1 and SHIP2 improves the ability of microglia to phagocytose Aβ and dead neurons. Thus, pan-SHIP1/2 inhibitors might be used to treat Alzheimer's disease.
Summary: B cells rapidly target antigen and surface-derived MHCII into peripheral MHCII compartments compatible with fast antigen processing right after internalisation.
Summary: Live imaging reveals neutrophil NADPH oxidase activity limits fungal growth and excessive inflammation during Aspergillus nidulans infection in larval zebrafish.
Summary: Channel proteins TRPC1 and Orai1 modulate Ca2+ entry, which inhibits ER-stress induced activation of macrophages and the development of the M1 phenotype.
IL-15Rα membrane anchorage in either cis or trans is required for stabilization of IL-15 and optimal signaling
Summary: Cytokines play a main role in the communication between immune cells to eliminate infected of transformed cells. We reveal how cells finely control the intensity of cytokine signaling.
Epidermal growth factor receptor signaling suppresses αvβ6 integrin and promotes periodontal inflammation and bone loss
Summary: Bacterial biofilms suppress αvβ6 integrin via EGFR signaling in gingival epithelial cells. Blocking EGFR activity reduces alveolar bone loss and inflammation in a ligature-induced experimental periodontitis mouse model.
Rat cytomegalovirus-encoded γ-chemokine vXCL1 is a highly adapted, species-specific agonist for rat XCR1-positive dendritic cells
Summary: Superior activation of G protein-coupled receptor signaling by a viral chemokine might lead to novel ideas for fine-tuning immune responses and improve control of infection.
Summary: Proton-secreting cells lining the epididymal tubule can switch their function to become previously unrecognized regulators of immune responses, while establishing close interactions with spermatozoa.
Discovery of aspirin-triggered eicosanoid-like mediators in a Drosophila metainflammation blood tumor model
Summary: Aspirin administration shrinks blood tumors and resolves inflammation in fruit flies. These effects correlate with high levels of linoleic acid-derived bioactive lipids.
Summary: Notch1, a key regulator of cell fate, acts upstream of cell division to dictate the asymmetric inheritance of T cell fate determinants by daughter cells.
Summary: T-cell migration depends on the nanoscale organisation of adhesion and regulatory proteins as revealed by single-molecule super-resolution fluorescence microscopy.
FcRn mediates fast recycling of endocytosed albumin and IgG from early macropinosomes in primary macrophages
Summary: The recycling of albumin and IgG in primary mouse macrophages expressing the human FcRn occurs through a novel fast recycling pathway from early macropinosomes to the cell surface, which protects these ligands from degradation.
Live imaging the foreign body response in zebrafish reveals how dampening inflammation reduces fibrosis
Summary: A translucent zebrafish model allows a window on the pathological angiogenic and fibrotic response to suture implantation and how this can be modulated by genetically or pharmacologically dampening inflammation.
Summary: DDX56 is a negative regulator of virus-triggered IFN-β induction that acts by disruputing the IRF3–IOP5 interaction to inhibit the import of IRF3 into the nucleus.
NKG2D–DAP10 signaling recruits EVL to the cytotoxic synapse to generate F-actin and promote NK cell cytotoxicity
Summary: The NK activating receptor NKG2D–DAP10 recruits EVL to the cytotoxic synapse via a Grb2–VAV1 signaling node to promote F-actin generation, target cell adhesion and the development of cell-mediated cytotoxicity.
TOOLS AND RESOURCES
High-resolution quantification of discrete phagocytic events by live cell time-lapse high-content microscopy imaging
Summary: Engulfment enumeration using high-content microscopy images of live cells phagocytosing in real time provides unprecedented high-resolution temporal data that allows new insights into this fundamental biological process.
Genetic engineering of Hoxb8-immortalized hematopoietic progenitors – a potent tool to study macrophage tissue migration
Summary: Validation of the use of ER-Hoxb8-immortalized hematopoietic progenitors combined with CRISPR/Cas9 technology as a potent tool to investigate macrophage functionalities with a large number of applications.