The immune response is an energy-demanding process that must be coordinated with systemic metabolic changes redirecting nutrients from stores to the immune system. Although this interplay is fundamental for the function of the immune system, the underlying mechanisms remain elusive. Our data show that the pro-inflammatory polarization of Drosophila macrophages is coupled to the production of the insulin antagonist ImpL2 through the activity of the transcription factor HIF1α. ImpL2 production, reflecting nutritional demands of activated macrophages, subsequently impairs insulin signaling in the fat body, thereby triggering FOXO-driven mobilization of lipoproteins. This metabolic adaptation is fundamental for the function of the immune system and an individual's resistance to infection. We demonstrated that analogically to Drosophila, mammalian immune-activated macrophages produce ImpL2 homolog IGFBP7 in a HIF1α-dependent manner and that enhanced IGFBP7 production by these cells induces mobilization of lipoproteins from hepatocytes. Hence, the production of ImpL2/IGFBP7 by macrophages represents an evolutionarily conserved mechanism by which macrophages alleviate insulin signaling in the central metabolic organ to secure nutrients necessary for their function upon bacterial infection.

• Klíčová slova
• Drosophila, ImpL2, insulin resistance, lipoproteins, macrophage polarization,
• MeSH
• antagonisté inzulinu metabolismus   farmakologie   MeSH
• bakteriální infekce * metabolismus   MeSH
• Drosophila metabolismus   MeSH
• inzulin metabolismus   MeSH
• inzulinová rezistence * MeSH
• makrofágy metabolismus   MeSH
• proteiny Drosophily * metabolismus   MeSH
• proteiny vázající insulinu podobné růstové faktory metabolismus   MeSH
• savci MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antagonisté inzulinu MeSH
• ImpL2 protein, Drosophila MeSH Prohlížeč
• inzulin MeSH
• proteiny Drosophily * MeSH
• proteiny vázající insulinu podobné růstové faktory MeSH

BACKGROUND: The international, multicenter registry LOGGIC Core BioClinical Data Bank aims to enhance the understanding of tumor biology in pediatric low-grade glioma (pLGG) and provide clinical and molecular data to support treatment decisions and interventional trial participation. Hence, the question arises whether implementation of RNA sequencing (RNA-Seq) using fresh frozen (FrFr) tumor tissue in addition to gene panel and DNA methylation analysis improves diagnostic accuracy and provides additional clinical benefit. METHODS: Analysis of patients aged 0 to 21 years, enrolled in Germany between April 2019 and February 2021, and for whom FrFr tissue was available. Central reference histopathology, immunohistochemistry, 850k DNA methylation analysis, gene panel sequencing, and RNA-Seq were performed. RESULTS: FrFr tissue was available in 178/379 enrolled cases. RNA-Seq was performed on 125 of these samples. We confirmed KIAA1549::BRAF-fusion (n = 71), BRAF V600E-mutation (n = 12), and alterations in FGFR1 (n = 14) as the most frequent alterations, among other common molecular drivers (n = 12). N = 16 cases (13%) presented rare gene fusions (eg, TPM3::NTRK1, EWSR1::VGLL1, SH3PXD2A::HTRA1, PDGFB::LRP1, GOPC::ROS1). In n = 27 cases (22%), RNA-Seq detected a driver alteration not otherwise identified (22/27 actionable). The rate of driver alteration detection was hereby increased from 75% to 97%. Furthermore, FGFR1 internal tandem duplications (n = 6) were only detected by RNA-Seq using current bioinformatics pipelines, leading to a change in analysis protocols. CONCLUSIONS: The addition of RNA-Seq to current diagnostic methods improves diagnostic accuracy, making precision oncology treatments (MEKi/RAFi/ERKi/NTRKi/FGFRi/ROSi) more accessible. We propose to include RNA-Seq as part of routine diagnostics for all pLGG patients, especially when no common pLGG alteration was identified.

• Klíčová slova
• RNA sequencing, actionable drivers, molecular profiling, pLGG, rare gene fusions,
• MeSH
• dítě MeSH
• DNA vazebné proteiny genetika   MeSH
• gliom * patologie   MeSH
• individualizovaná medicína MeSH
• lidé MeSH
• molekulární patologie MeSH
• protoonkogenní proteiny B-Raf * genetika   MeSH
• protoonkogenní proteiny genetika   MeSH
• sekvenování transkriptomu MeSH
• transkripční faktory genetika   MeSH
• tyrosinkinasy MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA vazebné proteiny MeSH
• protoonkogenní proteiny B-Raf * MeSH
• protoonkogenní proteiny MeSH
• transkripční faktory MeSH
• tyrosinkinasy MeSH
• VGLL1 protein, human MeSH Prohlížeč

Regulatory T cells (Tregs) are indispensable for maintaining self-tolerance by suppressing conventional T cells. On the other hand, Tregs promote tumor growth by inhibiting anticancer immunity. In this study, we identified that Tregs increase the quorum of self-reactive CD8+ T cells required for the induction of experimental autoimmune diabetes in mice. Their major suppression mechanism is limiting available IL-2, an essential T-cell cytokine. Specifically, Tregs inhibit the formation of a previously uncharacterized subset of antigen-stimulated KLRK1+ IL-7R+ (KILR) CD8+ effector T cells, which are distinct from conventional effector CD8+ T cells. KILR CD8+ T cells show superior cell-killing abilities in vivo. The administration of agonistic IL-2 immunocomplexes phenocopies the absence of Tregs, i.e., it induces KILR CD8+ T cells, promotes autoimmunity, and enhances antitumor responses in mice. Counterparts of KILR CD8+ T cells were found in the human blood, revealing them as a potential target for immunotherapy.

As well as protecting us from invading pathogens, like bacteria or viruses, our immune system can also identify dangerous cells of our own that may cause the body harm, such as cancer cells. Once detected, a population of immune cells called cytotoxic T cells launch into action to kill the potentially harmful cell. However, sometimes the immune system makes mistakes and attacks healthy cells which it misidentifies as being dangerous, leading to autoimmune diseases. Special immune cells called T regulatory lymphocytes, or ‘Tregs’, can suppress the activity of cytotoxic T cells, preventing them from hurting the body’s own cells. While this can have a positive impact and reduce the effects of autoimmunity, Tregs can also make the immune system less responsive to cancer cells and allow tumors to grow. But how Tregs alter the behavior of cytotoxic T cells during autoimmune diseases and cancer is poorly understood. While multiple mechanisms have been proposed, none of these have been tested in living animal models of these diseases. To address this, Tsyklauri et al. studied Tregs in laboratory mice which had been modified to have autoimmune diabetes, which is when the body attacks the cells responsible for producing insulin. The experiments revealed that Tregs take up a critical signaling molecule called IL-2 which cytotoxic T cells need to survive and multiply. As a result, there is less IL-2 molecules available in the environment, inhibiting the cytotoxic T cells’ activity. Furthermore, if Tregs are absent and there is an excess of IL-2, this causes cytotoxic T cells to transition into a previously unknown subset of T cells with superior killing abilities. Tsyklauri et al. were able to replicate these findings in two different groups of laboratory mice which had been modified to have cancer. This suggests that Tregs suppress the immune response to cancer cells and prevent autoimmunity using the same mechanism. In the future, this work could help researchers to develop therapies that alter the behavior of cytotoxic T cells and/or Tregs to either counteract autoimmune diseases, or help the body fight off cancer.

• Klíčová slova
• IL-2, T cells, autoimmunity, cytotoxic, immune suppression, immunology, inflammation, mouse, regulatory T cells,
• MeSH
• CD8-pozitivní T-lymfocyty MeSH
• diabetes mellitus 1. typu * patologie   MeSH
• imunologická tolerance MeSH
• interleukin-2 MeSH
• lektinové receptory NK-buněk - podrodina K MeSH
• lidé MeSH
• myši MeSH
• receptory interleukinu-7 MeSH
• regulační T-lymfocyty * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• interleukin-2 MeSH
• KLRK1 protein, human MeSH Prohlížeč
• Klrk1 protein, mouse MeSH Prohlížeč
• lektinové receptory NK-buněk - podrodina K MeSH
• receptory interleukinu-7 MeSH

The interplay among different cells in a tissue is essential for maintaining homeostasis. Although disease states have been traditionally attributed to individual cell types, increasing evidence and new therapeutic options have demonstrated the primary role of multicellular functions to understand health and disease, opening new avenues to understand pathogenesis and develop new treatment strategies. We recently described the cellular composition and dynamics of the human oral mucosa; however, the spatial arrangement of cells is needed to better understand a morphologically complex tissue. Here, we link single-cell RNA sequencing, spatial transcriptomics, and high-resolution multiplex fluorescence in situ hybridisation to characterise human oral mucosa in health and oral chronic inflammatory disease. We deconvolved expression for resolution enhancement of spatial transcriptomic data and defined highly specialised epithelial and stromal compartments describing location-specific immune programs. Furthermore, we spatially mapped a rare pathogenic fibroblast population localised in a highly immunogenic region, responsible for lymphocyte recruitment through CXCL8 and CXCL10 and with a possible role in pathological angiogenesis through ALOX5AP. Collectively, our study provides a comprehensive reference for the study of oral chronic disease pathogenesis.

• Klíčová slova
• cell biology, fibroblast, gingiva, human, immunology, inflammation, oral mucosa, periodontal disease, spatial genomics,
• MeSH
• chemokin CXCL10 genetika   MeSH
• fibroblasty MeSH
• interleukin-8 * metabolismus   MeSH
• lidé MeSH
• lymfocyty MeSH
• stanovení celkové genové exprese * MeSH
• transkriptom * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chemokin CXCL10 MeSH
• CXCL10 protein, human MeSH Prohlížeč
• CXCL8 protein, human MeSH Prohlížeč
• interleukin-8 * MeSH

Interleukin-2 is a pleiotropic cytokine that mediates both pro- and anti-inflammatory functions. Immune cells naturally differ in their sensitivity to IL-2 due to cell type and activation state-dependent expression of receptors and signaling pathway components. To probe differences in IL-2 signaling across cell types, we used structure-based design to create and profile a series of IL-2 variants with the capacity to titrate maximum signal strength in fine increments. One of these partial agonists, IL-2-REH, specifically expanded Foxp3+ regulatory T cells with reduced activity on CD8+ T cells due to cell type-intrinsic differences in IL-2 signaling. IL-2-REH elicited cell type-dependent differences in gene expression and provided mixed therapeutic results: showing benefit in the in vivo mouse dextran sulfate sodium (DSS) model of colitis, but no therapeutic efficacy in a transfer colitis model. Our findings show that cytokine partial agonists can be used to calibrate intrinsic differences in response thresholds across responding cell types to narrow pleiotropic actions, which may be generalizable to other cytokine and growth factor systems.

• Klíčová slova
• IL-2, biochemistry, chemical biology, cytokine signaling, human, immunology, inflammation, mouse,
• MeSH
• buněčné linie MeSH
• CD8-pozitivní T-lymfocyty metabolismus   MeSH
• cytokiny metabolismus   MeSH
• interleukin-2 agonisté   metabolismus   MeSH
• kolitida chemicky indukované   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• regulační T-lymfocyty metabolismus   MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• cytokiny MeSH
• interleukin-2 MeSH

The organizational integrity of the adaptive immune system is determined by functionally discrete subsets of CD4+ T cells, but it has remained unclear to what extent lineage choice is influenced by clonotypically expressed T-cell receptors (TCRs). To address this issue, we used a high-throughput approach to profile the αβ TCR repertoires of human naive and effector/memory CD4+ T-cell subsets, irrespective of antigen specificity. Highly conserved physicochemical and recombinatorial features were encoded on a subset-specific basis in the effector/memory compartment. Clonal tracking further identified forbidden and permitted transition pathways, mapping effector/memory subsets related by interconversion or ontogeny. Public sequences were largely confined to particular effector/memory subsets, including regulatory T cells (Tregs), which also displayed hardwired repertoire features in the naive compartment. Accordingly, these cumulative repertoire portraits establish a link between clonotype fate decisions in the complex world of CD4+ T cells and the intrinsic properties of somatically rearranged TCRs.

• Klíčová slova
• CDR3 properties, TCR repertoire, helper CD4+ subsets, human, immunology, inflammation, plasticity of CD4+ subsets,
• MeSH
• buněčný rodokmen imunologie   MeSH
• CD4-pozitivní T-lymfocyty imunologie   MeSH
• lidé MeSH
• receptory antigenů T-buněk alfa-beta imunologie   MeSH
• T-lymfocyty - podskupiny imunologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• receptory antigenů T-buněk alfa-beta MeSH

Visual cortical circuits show profound plasticity during early life and are later stabilized by molecular "brakes" limiting excessive rewiring beyond a critical period. The mechanisms coordinating the expression of these factors during the transition from development to adulthood remain unknown. We found that miR-29a expression in the visual cortex dramatically increases with age, but it is not experience-dependent. Precocious high levels of miR-29a blocked ocular dominance plasticity and caused an early appearance of perineuronal nets. Conversely, inhibition of miR-29a in adult mice using LNA antagomirs activated ocular dominance plasticity, reduced perineuronal nets, and restored their juvenile chemical composition. Activated adult plasticity had the typical functional and proteomic signature of critical period plasticity. Transcriptomic and proteomic studies indicated that miR-29a manipulation regulates the expression of plasticity brakes in specific cortical circuits. These data indicate that miR-29a is a regulator of the plasticity brakes promoting age-dependent stabilization of visual cortical connections.

• Klíčová slova
• DNA methylation, microRNA, ocular dominance plasticity, perineuronal net,
• MeSH
• mikro RNA * genetika   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neuroplasticita genetika   MeSH
• oční dominance genetika   MeSH
• proteomika MeSH
• zrakové korové centrum * MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• mikro RNA * MeSH
• MIRN29 microRNA, mouse MeSH Prohlížeč

Wnt/β-catenin signaling is a primary pathway for stem cell maintenance during tissue renewal and a frequent target for mutations in cancer. Impaired Wnt receptor endocytosis due to loss of the ubiquitin ligase RNF43 gives rise to Wnt-hypersensitive tumors that are susceptible to anti-Wnt-based therapy. Contrary to this paradigm, we identify a class of RNF43 truncating cancer mutations that induce β-catenin-mediated transcription, despite exhibiting retained Wnt receptor downregulation. These mutations interfere with a ubiquitin-independent suppressor role of the RNF43 cytosolic tail that involves Casein kinase 1 (CK1) binding and phosphorylation. Mechanistically, truncated RNF43 variants trap CK1 at the plasma membrane, thereby preventing β-catenin turnover and propelling ligand-independent target gene transcription. Gene editing of human colon stem cells shows that RNF43 truncations cooperate with p53 loss to drive a niche-independent program for self-renewal and proliferation. Moreover, these RNF43 variants confer decreased sensitivity to anti-Wnt-based therapy. Our data demonstrate the relevance of studying patient-derived mutations for understanding disease mechanisms and improved applications of precision medicine.

• Klíčová slova
• PORCN inhibitors, RNF43, Wnt signaling, cancer mutations, human colon organoids,
• MeSH
• beta-katenin genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• kasein kinasa I genetika   metabolismus   MeSH
• lidé MeSH
• nádorový supresorový protein p53 genetika   metabolismus   MeSH
• nádory genetika   metabolismus   patologie   MeSH
• signální dráha Wnt * MeSH
• ubikvitinligasy genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• beta-katenin MeSH
• CTNNB1 protein, human MeSH Prohlížeč
• kasein kinasa I MeSH
• nádorový supresorový protein p53 MeSH
• RNF43 protein, human MeSH Prohlížeč
• TP53 protein, human MeSH Prohlížeč
• ubikvitinligasy MeSH

IL-17 mediates immune protection from fungi and bacteria, as well as it promotes autoimmune pathologies. However, the regulation of the signal transduction from the IL-17 receptor (IL-17R) remained elusive. We developed a novel mass spectrometry-based approach to identify components of the IL-17R complex followed by analysis of their roles using reverse genetics. Besides the identification of linear ubiquitin chain assembly complex (LUBAC) as an important signal transducing component of IL-17R, we established that IL-17 signaling is regulated by a robust negative feedback loop mediated by TBK1 and IKKε. These kinases terminate IL-17 signaling by phosphorylating the adaptor ACT1 leading to the release of the essential ubiquitin ligase TRAF6 from the complex. NEMO recruits both kinases to the IL-17R complex, documenting that NEMO has an unprecedented negative function in IL-17 signaling, distinct from its role in NF-κB activation. Our study provides a comprehensive view of the molecular events of the IL-17 signal transduction and its regulation.

• Klíčová slova
• LUBAC, NEMO, IKKε, IL-17, TBK1,
• MeSH
• adaptorové proteiny signální transdukční genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• HeLa buňky MeSH
• kinasa I-kappa B genetika   metabolismus   MeSH
• lidé MeSH
• protein-serin-threoninkinasy genetika   metabolismus   MeSH
• receptory interleukinu-17 genetika   metabolismus   MeSH
• signální transdukce * MeSH
• zpětná vazba fyziologická * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• IKBKE protein, human MeSH Prohlížeč
• IKBKG protein, human MeSH Prohlížeč
• IL17RA protein, human MeSH Prohlížeč
• kinasa I-kappa B MeSH
• protein-serin-threoninkinasy MeSH
• receptory interleukinu-17 MeSH
• TBK1 protein, human MeSH Prohlížeč
• TRAF3IP2 protein, human MeSH Prohlížeč

Macrophages derive from multiple sources of hematopoietic progenitors. Most macrophages require colony-stimulating factor 1 receptor (CSF1R), but some macrophages persist in the absence of CSF1R. Here, we analyzed mpeg1:GFP-expressing macrophages in csf1r-deficient zebrafish and report that embryonic macrophages emerge followed by their developmental arrest. In larvae, mpeg1+ cell numbers then increased showing two distinct types in the skin: branched, putative Langerhans cells, and amoeboid cells. In contrast, although numbers also increased in csf1r-mutants, exclusively amoeboid mpeg1+ cells were present, which we showed by genetic lineage tracing to have a non-hematopoietic origin. They expressed macrophage-associated genes, but also showed decreased phagocytic gene expression and increased epithelial-associated gene expression, characteristic of metaphocytes, recently discovered ectoderm-derived cells. We further demonstrated that juvenile csf1r-deficient zebrafish exhibit systemic macrophage depletion. Thus, csf1r deficiency disrupts embryonic to adult macrophage development. Zebrafish deficient for csf1r are viable and permit analyzing the consequences of macrophage loss throughout life.

Immune cells called macrophages are found in all organs in the body. These cells are highly effective at eating and digesting large particles including dead cells and debris, and microorganisms such as bacteria. Macrophages are also instrumental in shaping developing organs and repairing tissues during life. Macrophages were, until recently, thought to be constantly replenished from cells circulating in the bloodstream. However, it turns out that separate populations of macrophages become established in most tissues during embryonic development and are maintained throughout life without further input. Previous studies of zebrafish, rodents and humans have shown that, when a gene called CSF1R is non-functional, macrophages are absent from many organs including the brain. However, some tissue-specific macrophages still persist, and it was not clear why these cells do not rely on the CSF1R gene while others do. Kuil et al. set out to decipher the precise requirement for the CSF1R gene in macrophage development in living zebrafish. The experiments used zebrafish that make a green fluorescent protein in their macrophages. As these fish are transparent, this meant that Kuil et al. could observe the cells within the living fish and isolate them to determine which genes are switched on and off. This approach revealed that zebrafish with a mutated version of the CSF1R gene make macrophages as embryos but that these cells then fail to multiply and migrate into the developing organs. This results in fewer macrophages in the zebrafish’s tissues, and an absence of these cells in the brain. Kuil et al. went on to show that new macrophages did emerge in zebrafish that were about two to three weeks old. However, unexpectedly, these new cells were not regular macrophages. Instead, they were a new recently identified cell-type called metaphocytes, which share similarities with macrophages but have a completely different origin, move faster and do not eat particles. Zebrafish lacking the CSF1R gene thus lose nearly all their macrophages but retain metaphocytes. These macrophage-free mutant zebrafish constitute an unprecedented tool for further studies looking to discriminate the different roles of macrophages and metaphocytes.

• Klíčová slova
• CSF1R, developmental biology, hematopoiesis, langerhans cells, macrophages, metaphocytes, microglia, zebrafish,
• MeSH
• dánio pruhované embryologie   MeSH
• makrofágy metabolismus   fyziologie   MeSH
• mikroglie metabolismus   fyziologie   MeSH
• proliferace buněk MeSH
• proteiny dánia pruhovaného metabolismus   fyziologie   MeSH
• receptory faktoru stimulujícího granulocyto-makrofágové kolonie metabolismus   fyziologie   MeSH
• stanovení celkové genové exprese MeSH
• tyrosinkinasové receptory MeSH
• tyrosinkinasy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• audiovizuální média MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• csf1ra protein, zebrafish MeSH Prohlížeč
• proteiny dánia pruhovaného MeSH
• receptory faktoru stimulujícího granulocyto-makrofágové kolonie MeSH
• tyrosinkinasové receptory MeSH
• tyrosinkinasy MeSH