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Interleukin-1β (IL-1β) is a key orchestrator of anti-microbial immunity whose secretion is typically dependent on activation of inflammasomes. However, many pathogens have evolved strategies to evade inflammasome activation. Here we describe an alternative, two-cell model for IL-1β release where invariant natural killer T (iNKT) cells use the death receptor pathway to instruct antigen-presenting cells to secrete IL-1β. Following cognate interactions with TLR-primed bone marrow-derived dendritic cells (BMDCs), iNKT cells rapidly translocate intracellular Fas ligand to the surface to engage Fas on BMDCs. Fas ligation activates a caspase-8-dependent signaling cascade in BMDCs that drives IL-1β release largely independent of inflammasomes. The apoptotic program initiated by Fas ligation rapidly transitions into a pyroptosis-like form of cell death mediated by gasdermin D. Together, our findings support a two-cell model for IL-1β secretion that may supersede inflammasome activation when cytosolic triggers fail. Stimulator of Interferon Genes (STING) is a critical component of host innate immune defense but can contribute to chronic autoimmune or autoinflammatory disease. Once activated, the cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) (cGAMP) synthase (cGAS)-STING pathway induces both type I interferon (IFN) expression and nuclear factor-κB (NF-κB)-mediated cytokine production. Currently, these two signaling arms are thought to be mediated by a single upstream kinase, TANK-binding kinase 1 (TBK1). Here, using genetic and pharmacological approaches, we show that TBK1 alone is dispensable for STING-induced NF-κB responses in human and mouse immune cells, as well as in vivo. We further demonstrate that TBK1 acts redundantly with IκB kinase ε (IKKε) to drive NF-κB upon STING activation. Interestingly, we show that activation of IFN regulatory factor 3 (IRF3) is highly dependent on TBK1 kinase activity, whereas NF-κB is significantly less sensitive to TBK1/IKKε kinase inhibition. Our work redefines signaling events downstream of cGAS-STING. Our findings further suggest that cGAS-STING will need to be targeted directly to effectively ameliorate the inflammation underpinning disorders associated with STING hyperactivity. The transition from the follicular B to the plasma cell stage is associated with large-scale changes in cell morphology. Here, we examine whether plasma cell development is also associated with changes in nuclear architecture. We find that the onset of plasma cell development is concomitant with a decline in remote genomic interactions; a gain in euchromatic character at loci encoding for factors that specify plasma cell fate, including Prdm1 and Atf4; and establishment of de novo inter-chromosomal hubs. We find that, in developing plasma cells and concurrent with transcriptional silencing, the Ebf1 locus repositions from an euchromatic to peri-centromeric heterochromatic environment. Finally, we find that inter-chromosomal hubs are enriched for the deposition of either H3K27Ac or H3K27me3. These data indicate that plasma cell fate is orchestrated by elaborate changes in genome topology and that epigenetic marks, linked with super-enhancers or transcriptionally repressed regions, are enriched at inter-chromosomal hubs. The Toll/IL-1R-domain-containing adaptor protein SARM1 is expressed primarily in the brain, where it mediates axonal degeneration. Roles for SARM1 in TLR signaling, viral infection, inflammasome activation, and chemokine and Xaf1 expression have also been described. read more Much of the evidence for SARM1 function relies on SARM1-deficient mice generated in 129 ESCs and backcrossed to B6. The Sarm1 gene lies in a gene-rich region encompassing Xaf1 and chemokine loci, which remain 129 in sequence. We therefore generated additional knockout strains on the B6 background, confirming the role of SARM1 in axonal degeneration and WNV infection, but not in VSV or LACV infection, or in chemokine or Xaf1 expression. Sequence variation in proapoptotic Xaf1 between B6 and 129 results in coding changes and distinct splice variants, which may account for phenotypes previously attributed to SARM1. Reevaluation of phenotypes in these strains will be critical for understanding the function of SARM1. There is increasing evidence that gut microbiome perturbations, also known as dysbiosis, can influence colorectal cancer development. To understand the mechanisms by which the gut microbiome modulates cancer susceptibility, we examine two wild-type mouse colonies with distinct gut microbial communities that develop significantly different tumor numbers using a mouse model of inflammation-associated tumorigenesis. We demonstrate that adaptive immune cells contribute to the different tumor susceptibilities associated with the two microbial communities. Mice that develop more tumors have increased colon lamina propria CD8+ IFNγ+ T cells before tumorigenesis but reduced CD8+ IFNγ+ T cells in tumors and adjacent tissues compared with mice that develop fewer tumors. Notably, intratumoral T cells in mice that develop more tumors exhibit increased exhaustion. Thus, these studies suggest that microbial dysbiosis can contribute to colon tumor susceptibility by hyperstimulating CD8 T cells to promote chronic inflammation and early T cell exhaustion, which can reduce anti-tumor immunity. The mechanical properties of the actin cortex regulate shape changes during cell division, cell migration, and tissue morphogenesis. We show that modulation of myosin II (MII) filament composition allows tuning of surface tension at the cortex to maintain cell shape during cytokinesis. Our results reveal that MIIA generates cortex tension, while MIIB acts as a stabilizing motor and its inclusion in MII hetero-filaments reduces cortex tension. Tension generation by MIIA drives faster cleavage furrow ingression and bleb formation. We also show distinct roles for the motor and tail domains of MIIB in maintaining cytokinetic fidelity. Maintenance of cortical stability by the motor domain of MIIB safeguards against shape instability-induced chromosome missegregation, while its tail domain mediates cortical localization at the terminal stages of cytokinesis to mediate cell abscission. Because most non-muscle contractile systems are cortical, this tuning mechanism will likely be applicable to numerous processes driven by myosin-II contractility.