RESUMO
Vitiligo is an autoimmune disease of the skin that targets pigment-producing melanocytes and results in patches of depigmentation that are visible as white spots. Recent research studies have yielded a strong mechanistic understanding of this disease. Autoreactive cytotoxic CD8+ T cells engage melanocytes and promote disease progression through the local production of IFN-γ, and IFN-γ-induced chemokines are then secreted from surrounding keratinocytes to further recruit T cells to the skin through a positive-feedback loop. Both topical and systemic treatments that block IFN-γ signaling can effectively reverse vitiligo in humans; however, disease relapse is common after stopping treatments. Autoreactive resident memory T cells are responsible for relapse, and new treatment strategies focus on eliminating these cells to promote long-lasting benefit. Here, we discuss basic, translational, and clinical research studies that provide insight into the pathogenesis of vitiligo, and how this insight has been utilized to create new targeted treatment strategies.
Assuntos
Vitiligo/etiologia , Vitiligo/terapia , Animais , Autoimunidade , Biomarcadores , Citocinas/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , Humanos , Memória Imunológica , Vitiligo/diagnósticoRESUMO
The discovery of interleukin-2 (IL-2) changed the molecular understanding of how the immune system is controlled. IL-2 is a pleiotropic cytokine, and dissecting the signaling pathways that allow IL-2 to control the differentiation and homeostasis of both pro- and anti-inflammatory T cells is fundamental to determining the molecular details of immune regulation. The IL-2 receptor couples to JAK tyrosine kinases and activates the STAT5 transcription factors. However, IL-2 does much more than control transcriptional programs; it is a key regulator of T cell metabolic programs. The development of global phosphoproteomic approaches has expanded the understanding of IL-2 signaling further, revealing the diversity of phosphoproteins that may be influenced by IL-2 in T cells. However, it is increasingly clear that within each T cell subset, IL-2 will signal within a framework of other signal transduction networks that together will shape the transcriptional and metabolic programs that determine T cell fate.
Assuntos
Interleucina-2/metabolismo , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Biomarcadores , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Citocinas/metabolismo , Humanos , Janus Quinases/metabolismo , Ativação Linfocitária/imunologia , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição STAT5/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
Common gamma receptor-dependent cytokines and their JAK/STAT pathways play pivotal roles in T cell immunity. Abnormal activation of this system was pervasive in diverse T cell malignancies assessed by pSTAT3/pSTAT5 phosphorylation. Activating mutations were described in some but not all cases. JAK1 and STAT3 were required for proliferation and survival of these T cell lines whether or not JAKs or STATs were mutated. Activating JAK and STAT mutations were not sufficient to initiate leukemic cell proliferation but rather only augmented signals from upstream in the cytokine pathway. Activation required the full pathway, including cytokine receptors acting as scaffolds and docking sites for required downstream JAK/STAT proteins. JAK kinase inhibitors have depressed leukemic T cell line proliferation. The insight that JAK/STAT system activation is pervasive in T cell malignancies suggests novel therapeutic approaches that include antibodies to common gamma cytokines, inhibitors of cytokine-receptor interactions, and JAK kinase inhibitors that may revolutionize therapy for T cell malignancies.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Imunoterapia/métodos , Janus Quinases/metabolismo , Linfoma de Células T/imunologia , Fatores de Transcrição STAT/metabolismo , Animais , Antineoplásicos/uso terapêutico , Carcinogênese , Citocinas/imunologia , Citocinas/metabolismo , Humanos , Subunidade gama Comum de Receptores de Interleucina/metabolismo , Linfoma de Células T/terapia , Receptores de Citocinas/antagonistas & inibidores , Transdução de SinaisRESUMO
Mammalian blastocyst formation involves the specification of the trophectoderm followed by the differentiation of the inner cell mass into embryonic epiblast and extra-embryonic primitive endoderm (PrE). During this time, the embryo maintains a window of plasticity and can redirect its cellular fate when challenged experimentally. In this context, we found that the PrE alone was sufficient to regenerate a complete blastocyst and continue post-implantation development. We identify an in vitro population similar to the early PrE in vivo that exhibits the same embryonic and extra-embryonic potency and can form complete stem cell-based embryo models, termed blastoids. Commitment in the PrE is suppressed by JAK/STAT signaling, collaborating with OCT4 and the sustained expression of a subset of pluripotency-related transcription factors that safeguard an enhancer landscape permissive for multi-lineage differentiation. Our observations support the notion that transcription factor persistence underlies plasticity in regulative development and highlight the importance of the PrE in perturbed development.
Assuntos
Blastocisto , Diferenciação Celular , Endoderma , Animais , Endoderma/metabolismo , Endoderma/citologia , Camundongos , Blastocisto/metabolismo , Blastocisto/citologia , Linhagem da Célula , Fator 3 de Transcrição de Octâmero/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Transdução de Sinais , Desenvolvimento Embrionário , Janus Quinases/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição STAT/metabolismo , Fatores de Transcrição/metabolismo , Feminino , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/citologiaRESUMO
Cytokines employ downstream Janus kinases (JAKs) to promote chronic inflammatory diseases. JAK1-dependent type 2 cytokines drive allergic inflammation, and patients with JAK1 gain-of-function (GoF) variants develop atopic dermatitis (AD) and asthma. To explore tissue-specific functions, we inserted a human JAK1 GoF variant (JAK1GoF) into mice and observed the development of spontaneous AD-like skin disease but unexpected resistance to lung inflammation when JAK1GoF expression was restricted to the stroma. We identified a previously unrecognized role for JAK1 in vagal sensory neurons in suppressing airway inflammation. Additionally, expression of Calcb/CGRPß was dependent on JAK1 in the vagus nerve, and CGRPß suppressed group 2 innate lymphoid cell function and allergic airway inflammation. Our findings reveal evolutionarily conserved but distinct functions of JAK1 in sensory neurons across tissues. This biology raises the possibility that therapeutic JAK inhibitors may be further optimized for tissue-specific efficacy to enhance precision medicine in the future.
Assuntos
Dermatite Atópica , Imunidade Inata , Pulmão , Células Receptoras Sensoriais , Animais , Humanos , Camundongos , Citocinas , Dermatite Atópica/imunologia , Inflamação , Pulmão/imunologia , Linfócitos , Células Receptoras Sensoriais/enzimologiaRESUMO
Thrombopoietin (THPO or TPO) is an essential cytokine for hematopoietic stem cell (HSC) maintenance and megakaryocyte differentiation. Here, we report the 3.4 Å resolution cryoelectron microscopy structure of the extracellular TPO-TPO receptor (TpoR or MPL) signaling complex, revealing the basis for homodimeric MPL activation and providing a structural rationalization for genetic loss-of-function thrombocytopenia mutations. The structure guided the engineering of TPO variants (TPOmod) with a spectrum of signaling activities, from neutral antagonists to partial- and super-agonists. Partial agonist TPOmod decoupled JAK/STAT from ERK/AKT/CREB activation, driving a bias for megakaryopoiesis and platelet production without causing significant HSC expansion in mice and showing superior maintenance of human HSCs in vitro. These data demonstrate the functional uncoupling of the two primary roles of TPO, highlighting the potential utility of TPOmod in hematology research and clinical HSC transplantation.
Assuntos
Receptores de Trombopoetina , Trombopoetina , Animais , Humanos , Camundongos , Ciclo Celular , Microscopia Crioeletrônica , Receptores de Trombopoetina/genética , Trombopoese , Metilação de DNARESUMO
Human inherited disorders of interferon-gamma (IFN-γ) immunity underlie severe mycobacterial diseases. We report X-linked recessive MCTS1 deficiency in men with mycobacterial disease from kindreds of different ancestries (from China, Finland, Iran, and Saudi Arabia). Complete deficiency of this translation re-initiation factor impairs the translation of a subset of proteins, including the kinase JAK2 in all cell types tested, including T lymphocytes and phagocytes. JAK2 expression is sufficiently low to impair cellular responses to interleukin-23 (IL-23) and partially IL-12, but not other JAK2-dependent cytokines. Defective responses to IL-23 preferentially impair the production of IFN-γ by innate-like adaptive mucosal-associated invariant T cells (MAIT) and γδ T lymphocytes upon mycobacterial challenge. Surprisingly, the lack of MCTS1-dependent translation re-initiation and ribosome recycling seems to be otherwise physiologically redundant in these patients. These findings suggest that X-linked recessive human MCTS1 deficiency underlies isolated mycobacterial disease by impairing JAK2 translation in innate-like adaptive T lymphocytes, thereby impairing the IL-23-dependent induction of IFN-γ.
Assuntos
Interferon gama , Janus Quinase 2 , Infecções por Mycobacterium , Humanos , Masculino , Proteínas de Ciclo Celular/metabolismo , Interferon gama/imunologia , Interleucina-12 , Interleucina-23 , Janus Quinase 2/metabolismo , Mycobacterium/fisiologia , Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/metabolismo , Proteínas Oncogênicas/metabolismoRESUMO
Interferons (IFNs) induce an antimicrobial state, protecting tissues from infection. Many viruses inhibit IFN signaling, but whether bacterial pathogens evade IFN responses remains unclear. Here, we demonstrate that the Shigella OspC family of type-III-secreted effectors blocks IFN signaling independently of its cell death inhibitory activity. Rather, IFN inhibition was mediated by the binding of OspC1 and OspC3 to the Ca2+ sensor calmodulin (CaM), blocking CaM kinase II and downstream JAK/STAT signaling. The growth of Shigella lacking OspC1 and OspC3 was attenuated in epithelial cells and in a murine model of infection. This phenotype was rescued in both models by the depletion of IFN receptors. OspC homologs conserved in additional pathogens not only bound CaM but also inhibited IFN, suggesting a widespread virulence strategy. These findings reveal a conserved but previously undescribed molecular mechanism of IFN inhibition and demonstrate the critical role of Ca2+ and IFN targeting in bacterial pathogenesis.
Assuntos
Interferons , Fatores de Virulência , Animais , Antivirais , Sinalização do Cálcio , Células Epiteliais/metabolismo , Interferons/metabolismo , Camundongos , Fatores de Virulência/metabolismoRESUMO
Prolonged activation of the type I interferon (IFN-I) pathway leads to autoimmune diseases such as systemic lupus erythematosus (SLE). Metabolic regulation of cytokine signaling is critical for cellular homeostasis. Through metabolomics analyses of IFN-ß-activated macrophages and an IFN-stimulated-response-element reporter screening, we identified spermine as a metabolite brake for Janus kinase (JAK) signaling. Spermine directly bound to the FERM and SH2 domains of JAK1 to impair JAK1-cytokine receptor interaction, thus broadly suppressing JAK1 phosphorylation triggered by cytokines IFN-I, IFN-II, interleukin (IL)-2, and IL-6. Peripheral blood mononuclear cells (PBMCs) from individuals with SLE showing decreased spermine concentrations exhibited enhanced IFN-I and lupus gene signatures. Spermine treatment attenuated autoimmune pathogenesis in SLE and psoriasis mice and reduced IFN-I signaling in monocytes from individuals with SLE. We synthesized a spermine derivative (spermine derivative 1 [SD1]) and showed that it had a potent immunosuppressive function. Our findings reveal spermine as a metabolic checkpoint for cellular homeostasis and a potential immunosuppressive molecule for controlling autoimmune disease.
Assuntos
Autoimunidade , Citocinas , Lúpus Eritematoso Sistêmico , Transdução de Sinais , Espermina , Animais , Espermina/metabolismo , Espermina/farmacologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Camundongos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Citocinas/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Janus Quinase 1/metabolismo , Fosforilação , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Psoríase/imunologia , Psoríase/metabolismo , Camundongos Endogâmicos C57BL , Janus Quinases/metabolismo , Feminino , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismoRESUMO
Cytokines are classically thought to stimulate downstream signaling pathways through monotonic activation of receptors. We describe a severe anemia resulting from a homozygous mutation (R150Q) in the cytokine erythropoietin (EPO). Surprisingly, the EPO R150Q mutant shows only a mild reduction in affinity for its receptor but has altered binding kinetics. The EPO mutant is less effective at stimulating erythroid cell proliferation and differentiation, even at maximally potent concentrations. While the EPO mutant can stimulate effectors such as STAT5 to a similar extent as the wild-type ligand, there is reduced JAK2-mediated phosphorylation of select downstream targets. This impairment in downstream signaling mechanistically arises from altered receptor dimerization dynamics due to extracellular binding changes. These results demonstrate how variation in a single cytokine can lead to biased downstream signaling and can thereby cause human disease. Moreover, we have defined a distinct treatable form of anemia through mutation identification and functional studies.
Assuntos
Anemia de Diamond-Blackfan/genética , Anemia de Diamond-Blackfan/patologia , Eritropoetina/genética , Mutação de Sentido Incorreto , Transdução de Sinais , Anemia de Diamond-Blackfan/terapia , Criança , Consanguinidade , Ativação Enzimática , Eritropoese , Eritropoetina/química , Feminino , Humanos , Janus Quinase 2/metabolismo , Cinética , Masculino , Receptores da Eritropoetina/química , Receptores da Eritropoetina/genética , Receptores da Eritropoetina/metabolismoRESUMO
Mammals have evolved neurophysiologic reflexes, such as coughing and scratching, to expel invading pathogens and noxious environmental stimuli. It is well established that these responses are also associated with chronic inflammatory diseases, including asthma and atopic dermatitis. However, the mechanisms by which inflammatory pathways promote sensations such as itch remain poorly understood. Here, we show that type 2 cytokines directly activate sensory neurons in both mice and humans. Further, we demonstrate that chronic itch is dependent on neuronal IL-4Rα and JAK1 signaling. We also observe that patients with recalcitrant chronic itch that failed other immunosuppressive therapies markedly improve when treated with JAK inhibitors. Thus, signaling mechanisms previously ascribed to the immune system may represent novel therapeutic targets within the nervous system. Collectively, this study reveals an evolutionarily conserved paradigm in which the sensory nervous system employs classical immune signaling pathways to influence mammalian behavior.
Assuntos
Prurido/imunologia , Células Receptoras Sensoriais/imunologia , Células Receptoras Sensoriais/metabolismo , Transdução de Sinais , Dermatopatias/imunologia , Animais , Gânglios Espinais , Humanos , Interleucina-13/imunologia , Interleucina-4/imunologia , Janus Quinase 1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Prurido/metabolismo , Dermatopatias/patologiaRESUMO
Human plasmacytoid dendritic cells (pDCs) are interleukin-3 (IL-3)-dependent cells implicated in autoimmunity, but the role of IL-3 in pDC biology is poorly understood. We found that IL-3-induced Janus kinase 2-dependent expression of SLC7A5 and SLC3A2, which comprise the large neutral amino acid transporter, was required for mammalian target of rapamycin complex 1 (mTORC1) nutrient sensor activation in response to toll-like receptor agonists. mTORC1 facilitated increased anabolic activity resulting in type I interferon, tumor necrosis factor, and chemokine production and the expression of the cystine transporter SLC7A11. Loss of function of these amino acid transporters synergistically blocked cytokine production by pDCs. Comparison of in vitro-activated pDCs with those from lupus nephritis lesions identified not only SLC7A5, SLC3A2, and SLC7A11 but also ectonucleotide pyrophosphatase-phosphodiesterase 2 (ENPP2) as components of a shared transcriptional signature, and ENPP2 inhibition also blocked cytokine production. Our data identify additional therapeutic targets for autoimmune diseases in which pDCs are implicated.
Assuntos
Sistemas de Transporte de Aminoácidos/genética , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Regulação da Expressão Gênica , Sistemas de Transporte de Aminoácidos/metabolismo , Autoimunidade , Biomarcadores , Citocinas/genética , Citocinas/metabolismo , Suscetibilidade a Doenças , Metabolismo Energético , Humanos , Imunidade , Transdução de SinaisRESUMO
Tumor-infiltrating myeloid cells (TIMs) are crucial cell populations involved in tumor immune escape, and their functions are regulated by multiple epigenetic mechanisms. The precise regulation mode of RNA N6-methyladenosine (m6A) modification in controlling TIM function is still poorly understood. Our study revealed that the increased expression of methyltransferase-like 3 (METTL3) in TIMs was correlated with the poor prognosis of colon cancer patients, and myeloid deficiency of METTL3 attenuated tumor growth in mice. METTL3 mediated m6A modification on Jak1 mRNA in TIMs, the m6A-YTHDF1 axis enhanced JAK1 protein translation efficiency and subsequent phosphorylation of STAT3. Lactate accumulated in tumor microenvironment potently induced METTL3 upregulation in TIMs via H3K18 lactylation. Interestingly, we identified two lactylation modification sites in the zinc-finger domain of METTL3, which was essential for METTL3 to capture target RNA. Our results emphasize the importance of lactylation-driven METTL3-mediated RNA m6A modification for promoting the immunosuppressive capacity of TIMs.
Assuntos
Metiltransferases , Neoplasias , Adenosina/metabolismo , Animais , Humanos , Terapia de Imunossupressão , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Células Mieloides/metabolismo , RNA , Microambiente TumoralRESUMO
Citrulline can be converted into argininosuccinate by argininosuccinate synthetase (ASS1) in the urea cycle and the citrulline-nitric oxide cycle. However, the regulation and biological function of citrulline metabolism remain obscure in the immune system. Unexpectedly, we found that macrophage citrulline declines rapidly after interferon gamma (IFN-γ) and/or lipopolysaccharide (LPS) stimulation, which is required for efficient proinflammatory signaling activation. Mechanistically, IFN-γ and/or LPS stimulation promotes signal transducers and activators of transcription 1 (STAT1)-mediated ASS1 transcription and Janus kinase2 (JAK2)-mediated phosphorylation of ASS1 at tyrosine 87, thereby leading to citrulline depletion. Reciprocally, increased citrulline directly binds to JAK2 and inhibits JAK2-STAT1 signaling. Blockage of ASS1-mediated citrulline depletion suppresses the host defense against bacterial infection in vivo. We therefore define a central role for ASS1 in controlling inflammatory macrophage activation and antibacterial defense through depletion of cellular citrulline and, further, identify citrulline as an innate immune-signaling metabolite that engages a metabolic checkpoint for proinflammatory responses.
Assuntos
Argininossuccinato Sintase/metabolismo , Citrulina/metabolismo , Imunidade Inata , Inflamação/enzimologia , Listeriose/enzimologia , Ativação de Macrófagos , Macrófagos/enzimologia , Animais , Argininossuccinato Sintase/genética , Modelos Animais de Doenças , Células HEK293 , Humanos , Inflamação/genética , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Listeria monocytogenes/imunologia , Listeriose/genética , Listeriose/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Células RAW 264.7 , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de SinaisRESUMO
Autoinflammatory disease can result from monogenic errors of immunity. We describe a patient with early-onset multi-organ immune dysregulation resulting from a mosaic, gain-of-function mutation (S703I) in JAK1, encoding a kinase essential for signaling downstream of >25 cytokines. By custom single-cell RNA sequencing, we examine mosaicism with single-cell resolution. We find that JAK1 transcription was predominantly restricted to a single allele across different cells, introducing the concept of a mutational "transcriptotype" that differs from the genotype. Functionally, the mutation increases JAK1 activity and transactivates partnering JAKs, independent of its catalytic domain. S703I JAK1 is not only hypermorphic for cytokine signaling but also neomorphic, as it enables signaling cascades not canonically mediated by JAK1. Given these results, the patient was treated with tofacitinib, a JAK inhibitor, leading to the rapid resolution of clinical disease. These findings offer a platform for personalized medicine with the concurrent discovery of fundamental biological principles.
Assuntos
Doenças Hereditárias Autoinflamatórias/genética , Doenças Hereditárias Autoinflamatórias/patologia , Janus Quinase 1/genética , Síndrome de Resposta Inflamatória Sistêmica/genética , Síndrome de Resposta Inflamatória Sistêmica/patologia , Adolescente , COVID-19/mortalidade , Domínio Catalítico/genética , Linhagem Celular , Citocinas/metabolismo , Feminino , Mutação com Ganho de Função/genética , Genótipo , Células HEK293 , Doenças Hereditárias Autoinflamatórias/tratamento farmacológico , Humanos , Janus Quinase 1/antagonistas & inibidores , Mosaicismo , Piperidinas/uso terapêutico , Medicina de Precisão/métodos , Pirimidinas/uso terapêutico , Transdução de Sinais/imunologia , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológicoRESUMO
Ten-eleven translocation (TET) proteins are dioxygenases that convert 5-methylcytosine (5mC) into 5-hydroxylmethylcytosine (5hmC) in DNA and RNA. However, their involvement in adult stem cell regulation remains unclear. Here, we identify a novel enzymatic activity-independent function of Tet in the Drosophila germline stem cell (GSC) niche. Tet activates the expression of Dpp, the fly homologue of BMP, in the ovary stem cell niche, thereby controlling GSC self-renewal. Depletion of Tet disrupts Dpp production, leading to premature GSC loss. Strikingly, both wild-type and enzyme-dead mutant Tet proteins rescue defective BMP signaling and GSC loss when expressed in the niche. Mechanistically, Tet interacts directly with Bap55 and Stat92E, facilitating recruitment of the Polybromo Brahma associated protein (PBAP) complex to the dpp enhancer and activating Dpp expression. Furthermore, human TET3 can effectively substitute for Drosophila Tet in the niche to support BMP signaling and GSC self-renewal. Our findings highlight a conserved novel catalytic activity-independent role of Tet as a scaffold protein in supporting niche signaling for adult stem cell self-renewal.
Assuntos
Dioxigenases , Proteínas de Drosophila , Drosophila melanogaster , Animais , Feminino , Humanos , Diferenciação Celular/genética , Drosophila/genética , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Células Germinativas/metabolismo , Nicho de Células-Tronco/fisiologia , Células-Tronco/metabolismo , Dioxigenases/metabolismoRESUMO
Tumor interferon (IFN) signaling promotes PD-L1 expression to suppress T cell-mediated immunosurveillance. We identify the IFN-stimulated non-coding RNA 1 (INCR1) as a long noncoding RNA (lncRNA) transcribed from the PD-L1 locus and show that INCR1 controls IFNγ signaling in multiple tumor types. Silencing INCR1 decreases the expression of PD-L1, JAK2, and several other IFNγ-stimulated genes. INCR1 knockdown sensitizes tumor cells to cytotoxic T cell-mediated killing, improving CAR T cell therapy. We discover that PD-L1 and JAK2 transcripts are negatively regulated by binding to HNRNPH1, a nuclear ribonucleoprotein. The primary transcript of INCR1 binds HNRNPH1 to block its inhibitory effects on the neighboring genes PD-L1 and JAK2, enabling their expression. These findings introduce a mechanism of tumor IFNγ signaling regulation mediated by the lncRNA INCR1 and suggest a therapeutic target for cancer immunotherapy.
Assuntos
Antígeno B7-H1/genética , Interferon gama/metabolismo , RNA Longo não Codificante/genética , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imunoterapia , Imunoterapia Adotiva/métodos , Interferon gama/genética , Interferons/genética , Interferons/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Proteína 2 Ligante de Morte Celular Programada 1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T CitotóxicosRESUMO
Inborn errors of immunity (IEI) or primary immune deficiencies (PIDD) are caused by variants in genes encoding for molecules that are relevant to the innate or adaptive immune response. To date, defects in more than 450 different genes have been identified as causes of IEI, causing a constellation of heterogeneous clinical manifestations ranging from increased susceptibility to infection, to autoimmunity or autoinflammation. IEI that are mainly characterized by autoinflammation are broadly classified according to the inflammatory pathway that they predominantly perturb. Among autoinflammatory IEI are those characterized by the transcriptional upregulation of type I interferon genes and are referred to as interferonopathies. Within the spectrum of interferonopathies, genetic defects that affect the proteasome have been described to cause autoinflammatory disease and represent a growing area of investigation. This review is focused on describing the clinical, genetic, and molecular aspects of IEI associated with mutations that affect the proteasome and how the study of these diseases has contributed to delineate therapeutic interventions.
Assuntos
Autoimunidade , Complexo de Endopeptidases do Proteassoma , Humanos , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Autoimunidade/genética , Mutação/genética , SíndromeRESUMO
Inborn errors of immunity (IEIs) encompass a diverse spectrum of genetic disorders that disrupt the intricate mechanisms of the immune system, leading to a variety of clinical manifestations. Traditionally associated with an increased susceptibility to recurrent infections, IEIs have unveiled a broader clinical landscape, encompassing immune dysregulation disorders characterized by autoimmunity, severe allergy, lymphoproliferation, and even malignancy. This review delves into the intricate interplay between IEIs and the JAK-STAT signaling pathway, a critical regulator of immune homeostasis. Mutations within this pathway can lead to a wide array of clinical presentations, even within the same gene. This heterogeneity poses a significant challenge, necessitating individually tailored therapeutic approaches to effectively manage the diverse manifestations of these disorders. Additionally, JAK-STAT pathway defects can lead to simultaneous susceptibility to both infection and immune dysregulation. JAK inhibitors, with their ability to suppress JAK-STAT signaling, have emerged as powerful tools in controlling immune dysregulation. However, questions remain regarding the optimal selection and dosing regimens for each specific condition. Hematopoietic stem cell transplantation (HSCT) holds promise as a curative therapy for many JAK-STAT pathway disorders, but this procedure carries significant risks. The use of JAK inhibitors as a bridge to HSCT has been proposed as a potential strategy to mitigate these risks.
Assuntos
Doenças do Sistema Imunitário , Inibidores de Janus Quinases , Humanos , Transdução de Sinais , Inibidores de Janus Quinases/uso terapêutico , Inibidores de Janus Quinases/farmacologia , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismoRESUMO
The gene expression programs that define the identity of each cell are controlled by master transcription factors (TFs) that bind cell-type-specific enhancers, as well as signaling factors, which bring extracellular stimuli to these enhancers. Recent studies have revealed that master TFs form phase-separated condensates with the Mediator coactivator at super-enhancers. Here, we present evidence that signaling factors for the WNT, TGF-ß, and JAK/STAT pathways use their intrinsically disordered regions (IDRs) to enter and concentrate in Mediator condensates at super-enhancers. We show that the WNT coactivator ß-catenin interacts both with components of condensates and DNA-binding factors to selectively occupy super-enhancer-associated genes. We propose that the cell-type specificity of the response to signaling is mediated in part by the IDRs of the signaling factors, which cause these factors to partition into condensates established by the master TFs and Mediator at genes with prominent roles in cell identity.