RESUMEN
Ongoing, early-stage clinical trials illustrate the translational potential of human pluripotent stem cell (hPSC)-based cell therapies in Parkinson's disease (PD). However, an unresolved challenge is the extensive cell death following transplantation. Here, we performed a pooled CRISPR-Cas9 screen to enhance postmitotic dopamine neuron survival in vivo. We identified p53-mediated apoptotic cell death as a major contributor to dopamine neuron loss and uncovered a causal link of tumor necrosis factor alpha (TNF-α)-nuclear factor κB (NF-κB) signaling in limiting cell survival. As a translationally relevant strategy to purify postmitotic dopamine neurons, we identified cell surface markers that enable purification without the need for genetic reporters. Combining cell sorting and treatment with adalimumab, a clinically approved TNF-α inhibitor, enabled efficient engraftment of postmitotic dopamine neurons with extensive reinnervation and functional recovery in a preclinical PD mouse model. Thus, transient TNF-α inhibition presents a clinically relevant strategy to enhance survival and enable engraftment of postmitotic hPSC-derived dopamine neurons in PD.
Asunto(s)
Supervivencia Celular , Neuronas Dopaminérgicas , FN-kappa B , Factor de Necrosis Tumoral alfa , Proteína p53 Supresora de Tumor , Neuronas Dopaminérgicas/metabolismo , Animales , Humanos , FN-kappa B/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ratones , Supervivencia Celular/efectos de los fármacos , Transducción de Señal , Enfermedad de Parkinson/metabolismo , Células Madre Pluripotentes/metabolismo , Apoptosis , Modelos Animales de Enfermedad , Sistemas CRISPR-CasRESUMEN
Sepsis is a systemic response to infection with life-threatening consequences. Our understanding of the molecular and cellular impact of sepsis across organs remains rudimentary. Here, we characterize the pathogenesis of sepsis by measuring dynamic changes in gene expression across organs. To pinpoint molecules controlling organ states in sepsis, we compare the effects of sepsis on organ gene expression to those of 6 singles and 15 pairs of recombinant cytokines. Strikingly, we find that the pairwise effects of tumor necrosis factor plus interleukin (IL)-18, interferon-gamma or IL-1ß suffice to mirror the impact of sepsis across tissues. Mechanistically, we map the cellular effects of sepsis and cytokines by computing changes in the abundance of 195 cell types across 9 organs, which we validate by whole-mouse spatial profiling. Our work decodes the cytokine cacophony in sepsis into a pairwise cytokine message capturing the gene, cell and tissue responses of the host to the disease.
Asunto(s)
Citocinas , Sepsis , Ratones , Animales , Interleucina-6/genética , Factor de Necrosis Tumoral alfa/metabolismo , Interferón gamma , Sepsis/genéticaRESUMEN
COVID-19 is characterized by excessive production of pro-inflammatory cytokines and acute lung damage associated with patient mortality. While multiple inflammatory cytokines are produced by innate immune cells during SARS-CoV-2 infection, we found that only the combination of TNF-α and IFN-γ induced inflammatory cell death characterized by inflammatory cell death, PANoptosis. Mechanistically, TNF-α and IFN-γ co-treatment activated the JAK/STAT1/IRF1 axis, inducing nitric oxide production and driving caspase-8/FADD-mediated PANoptosis. TNF-α and IFN-γ caused a lethal cytokine shock in mice that mirrors the tissue damage and inflammation of COVID-19, and inhibiting PANoptosis protected mice from this pathology and death. Furthermore, treating with neutralizing antibodies against TNF-α and IFN-γ protected mice from mortality during SARS-CoV-2 infection, sepsis, hemophagocytic lymphohistiocytosis, and cytokine shock. Collectively, our findings suggest that blocking the cytokine-mediated inflammatory cell death signaling pathway identified here may benefit patients with COVID-19 or other infectious and autoinflammatory diseases by limiting tissue damage/inflammation.
Asunto(s)
COVID-19/inmunología , COVID-19/patología , Síndrome de Liberación de Citoquinas/inmunología , Síndrome de Liberación de Citoquinas/patología , Interferón gamma/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Anticuerpos Neutralizantes/administración & dosificación , Muerte Celular , Modelos Animales de Enfermedad , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Inflamación/inmunología , Inflamación/patología , Linfohistiocitosis Hemofagocítica/inducido químicamente , Masculino , Ratones , Ratones Transgénicos , Células THP-1RESUMEN
TANK binding kinase 1 (TBK1) regulates IFN-I, NF-κB, and TNF-induced RIPK1-dependent cell death (RCD). In mice, biallelic loss of TBK1 is embryonically lethal. We discovered four humans, ages 32, 26, 7, and 8 from three unrelated consanguineous families with homozygous loss-of-function mutations in TBK1. All four patients suffer from chronic and systemic autoinflammation, but not severe viral infections. We demonstrate that TBK1 loss results in hypomorphic but sufficient IFN-I induction via RIG-I/MDA5, while the system retains near intact IL-6 induction through NF-κB. Autoinflammation is driven by TNF-induced RCD as patient-derived fibroblasts experienced higher rates of necroptosis in vitro, and CC3 was elevated in peripheral blood ex vivo. Treatment with anti-TNF dampened the baseline circulating inflammatory profile and ameliorated the clinical condition in vivo. These findings highlight the plasticity of the IFN-I response and underscore a cardinal role for TBK1 in the regulation of RCD.
Asunto(s)
Inflamación/enzimología , Proteínas Serina-Treonina Quinasas/deficiencia , Factor de Necrosis Tumoral alfa/farmacología , Células A549 , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis , Autoinmunidad/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Muerte Celular/efectos de los fármacos , Citocinas/metabolismo , Enzima Desubiquitinante CYLD/metabolismo , Femenino , Células HEK293 , Homocigoto , Humanos , Quinasa I-kappa B/metabolismo , Inmunofenotipificación , Inflamación/patología , Interferón Tipo I/metabolismo , Interferón gamma/metabolismo , Mutación con Pérdida de Función/genética , Masculino , Linaje , Fosforilación/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Receptores de Reconocimiento de Patrones/metabolismo , Receptor Toll-Like 3/metabolismo , Transcriptoma/genética , Vesiculovirus/efectos de los fármacos , Vesiculovirus/fisiologíaRESUMEN
Missense mutations in PLCG2 can cause autoinflammation with phospholipase C gamma 2-associated antibody deficiency and immune dysregulation (APLAID). Here, we generated a mouse model carrying an APLAID mutation (p.Ser707Tyr) and found that inflammatory infiltrates in the skin and lungs were only partially ameliorated by removing inflammasome function via the deletion of caspase-1. Also, deleting interleukin-6 or tumor necrosis factor did not fully prevent APLAID mutant mice from autoinflammation. Overall, these findings are in accordance with the poor response individuals with APLAID have to treatments that block interleukin-1, JAK1/2 or tumor necrosis factor. Cytokine analysis revealed increased granulocyte colony-stimulating factor (G-CSF) levels as the most distinct feature in mice and individuals with APLAID. Remarkably, treatment with a G-CSF antibody completely reversed established disease in APLAID mice. Furthermore, excessive myelopoiesis was normalized and lymphocyte numbers rebounded. APLAID mice were also fully rescued by bone marrow transplantation from healthy donors, associated with reduced G-CSF production, predominantly from non-hematopoietic cells. In summary, we identify APLAID as a G-CSF-driven autoinflammatory disease, for which targeted therapy is feasible.
Asunto(s)
Trasplante de Médula Ósea , Factor Estimulante de Colonias de Granulocitos , Animales , Ratones , Citocinas , Interleucina-1 , Factor de Necrosis Tumoral alfa/genética , Síndromes de Inmunodeficiencia/genética , Síndromes de Inmunodeficiencia/inmunología , Síndromes de Inmunodeficiencia/metabolismoRESUMEN
Humoral responses in coronavirus disease 2019 (COVID-19) are often of limited durability, as seen with other human coronavirus epidemics. To address the underlying etiology, we examined post mortem thoracic lymph nodes and spleens in acute SARS-CoV-2 infection and observed the absence of germinal centers and a striking reduction in Bcl-6+ germinal center B cells but preservation of AID+ B cells. Absence of germinal centers correlated with an early specific block in Bcl-6+ TFH cell differentiation together with an increase in T-bet+ TH1 cells and aberrant extra-follicular TNF-α accumulation. Parallel peripheral blood studies revealed loss of transitional and follicular B cells in severe disease and accumulation of SARS-CoV-2-specific "disease-related" B cell populations. These data identify defective Bcl-6+ TFH cell generation and dysregulated humoral immune induction early in COVID-19 disease, providing a mechanistic explanation for the limited durability of antibody responses in coronavirus infections, and suggest that achieving herd immunity through natural infection may be difficult.
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Infecciones por Coronavirus/inmunología , Centro Germinal/inmunología , Neumonía Viral/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Anciano , Anciano de 80 o más Años , Linfocitos B/inmunología , COVID-19 , Femenino , Centro Germinal/patología , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Proteínas Proto-Oncogénicas c-bcl-6/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Bazo/inmunología , Bazo/patología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Cell function and activity are regulated through integration of signaling, epigenetic, transcriptional, and metabolic pathways. Here, we introduce INs-seq, an integrated technology for massively parallel recording of single-cell RNA sequencing (scRNA-seq) and intracellular protein activity. We demonstrate the broad utility of INs-seq for discovering new immune subsets by profiling different intracellular signatures of immune signaling, transcription factor combinations, and metabolic activity. Comprehensive mapping of Arginase 1-expressing cells within tumor models, a metabolic immune signature of suppressive activity, discovers novel Arg1+ Trem2+ regulatory myeloid (Mreg) cells and identifies markers, metabolic activity, and pathways associated with these cells. Genetic ablation of Trem2 in mice inhibits accumulation of intra-tumoral Mreg cells, leading to a marked decrease in dysfunctional CD8+ T cells and reduced tumor growth. This study establishes INs-seq as a broadly applicable technology for elucidating integrated transcriptional and intra-cellular maps and identifies the molecular signature of myeloid suppressive cells in tumors.
Asunto(s)
Glicoproteínas de Membrana/metabolismo , Neoplasias/patología , ARN Citoplasmático Pequeño/química , Receptores Inmunológicos/metabolismo , Animales , Arginasa/genética , Arginasa/metabolismo , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Femenino , Regulación de la Expresión Génica , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Lipopolisacáridos/farmacología , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Neoplasias/inmunología , Neoplasias/metabolismo , ARN Citoplasmático Pequeño/metabolismo , Receptores Inmunológicos/genética , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Factores de Transcripción/metabolismo , Microambiente Tumoral , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Tumor necrosis factor (TNF) drives chronic inflammation and cell death in the intestine, and blocking TNF is a therapeutic approach in inflammatory bowel disease (IBD). Despite this knowledge, the pathways that protect the intestine from TNF are incompletely understood. Here we demonstrate that group 3 innate lymphoid cells (ILC3s) protect the intestinal epithelium from TNF-induced cell death. This occurs independent of interleukin-22 (IL-22), and we identify that ILC3s are a dominant source of heparin-binding epidermal growth factor-like growth factor (HB-EGF). ILC3s produce HB-EGF in response to prostaglandin E2 (PGE2) and engagement of the EP2 receptor. Mice lacking ILC3-derived HB-EGF exhibit increased susceptibility to TNF-mediated epithelial cell death and experimental intestinal inflammation. Finally, human ILC3s produce HB-EGF and are reduced from the inflamed intestine. These results define an essential role for ILC3-derived HB-EGF in protecting the intestine from TNF and indicate that disruption of this pathway contributes to IBD.
Asunto(s)
Factor de Crecimiento Similar a EGF de Unión a Heparina/inmunología , Inmunidad Innata/inmunología , Inflamación/inmunología , Intestinos/inmunología , Linfocitos/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Células Epiteliales/inmunología , Mucosa Intestinal/inmunología , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/inmunologíaRESUMEN
Clinical benefits of cytokine blockade in ileal Crohn's disease (iCD) are limited to a subset of patients. Here, we applied single-cell technologies to iCD lesions to address whether cellular heterogeneity contributes to treatment resistance. We found that a subset of patients expressed a unique cellular module in inflamed tissues that consisted of IgG plasma cells, inflammatory mononuclear phagocytes, activated T cells, and stromal cells, which we named the GIMATS module. Analysis of ligand-receptor interaction pairs identified a distinct network connectivity that likely drives the GIMATS module. Strikingly, the GIMATS module was also present in a subset of patients in four independent iCD cohorts (n = 441), and its presence at diagnosis correlated with failure to achieve durable corticosteroid-free remission upon anti-TNF therapy. These results emphasize the limitations of current diagnostic assays and the potential for single-cell mapping tools to identify novel biomarkers of treatment response and tailored therapeutic opportunities.
Asunto(s)
Enfermedad de Crohn/terapia , Citocinas/inmunología , Intestinos/patología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/patología , Humanos , Inmunoterapia/métodos , Fagocitos/patología , Análisis de la Célula Individual , Células del Estroma/patología , Linfocitos T/patologíaRESUMEN
Cutaneous TRPV1+ neurons directly sense noxious stimuli, inflammatory cytokines, and pathogen-associated molecules and are required for innate immunity against some skin pathogens. Important unanswered questions are whether TRPV1+ neuron activation in isolation is sufficient to initiate innate immune responses and what is the biological function for TRPV1+ neuron-initiated immune responses. We used TRPV1-Ai32 optogenetic mice and cutaneous light stimulation to activate cutaneous neurons in the absence of tissue damage or pathogen-associated products. We found that TRPV1+ neuron activation was sufficient to elicit a local type 17 immune response that augmented host defense to C. albicans and S. aureus. Moreover, local neuron activation elicited type 17 responses and augmented host defense at adjacent, unstimulated skin through a nerve reflex arc. These data show the sufficiency of TRPV1+ neuron activation for host defense and demonstrate the existence of functional anticipatory innate immunity at sites adjacent to infection that depends on antidromic neuron activation.
Asunto(s)
Inmunidad Innata/inmunología , Interleucina-23/metabolismo , Interleucina-6/metabolismo , Células Receptoras Sensoriales/inmunología , Piel/inmunología , Canales Catiónicos TRPV/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Candida albicans/inmunología , Inflamación/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Optogenética/métodos , Piel/microbiología , Staphylococcus aureus/inmunología , Canales Catiónicos TRPV/genéticaRESUMEN
Genome-wide association studies (GWAS) have revealed risk alleles for ulcerative colitis (UC). To understand their cell type specificities and pathways of action, we generate an atlas of 366,650 cells from the colon mucosa of 18 UC patients and 12 healthy individuals, revealing 51 epithelial, stromal, and immune cell subsets, including BEST4+ enterocytes, microfold-like cells, and IL13RA2+IL11+ inflammatory fibroblasts, which we associate with resistance to anti-TNF treatment. Inflammatory fibroblasts, inflammatory monocytes, microfold-like cells, and T cells that co-express CD8 and IL-17 expand with disease, forming intercellular interaction hubs. Many UC risk genes are cell type specific and co-regulated within relatively few gene modules, suggesting convergence onto limited sets of cell types and pathways. Using this observation, we nominate and infer functions for specific risk genes across GWAS loci. Our work provides a framework for interrogating complex human diseases and mapping risk variants to cell types and pathways.
Asunto(s)
Colitis Ulcerosa/patología , Colon/metabolismo , Adulto , Anciano , Anticuerpos Monoclonales/uso terapéutico , Bestrofinas/metabolismo , Antígenos CD8/metabolismo , Estudios de Casos y Controles , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/metabolismo , Colon/patología , Enterocitos/citología , Enterocitos/metabolismo , Femenino , Sitios Genéticos , Estudio de Asociación del Genoma Completo , Humanos , Interleucina-17/metabolismo , Masculino , Persona de Mediana Edad , Factores de Riesgo , Linfocitos T/citología , Linfocitos T/metabolismo , Trombospondinas/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Adulto JovenRESUMEN
New opportunities are needed to increase immune checkpoint blockade (ICB) benefit. Whereas the interferon (IFN)γ pathway harbors both ICB resistance factors and therapeutic opportunities, this has not been systematically investigated for IFNγ-independent signaling routes. A genome-wide CRISPR/Cas9 screen to sensitize IFNγ receptor-deficient tumor cells to CD8 T cell elimination uncovered several hits mapping to the tumor necrosis factor (TNF) pathway. Clinically, we show that TNF antitumor activity is only limited in tumors at baseline and in ICB non-responders, correlating with its low abundance. Taking advantage of the genetic screen, we demonstrate that ablation of the top hit, TRAF2, lowers the TNF cytotoxicity threshold in tumors by redirecting TNF signaling to favor RIPK1-dependent apoptosis. TRAF2 loss greatly enhanced the therapeutic potential of pharmacologic inhibition of its interaction partner cIAP, another screen hit, thereby cooperating with ICB. Our results suggest that selective reduction of the TNF cytotoxicity threshold increases the susceptibility of tumors to immunotherapy.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Inmunoterapia , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Apoptosis/efectos de los fármacos , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/metabolismo , Línea Celular Tumoral , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Interferón gamma/metabolismo , Estimación de Kaplan-Meier , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias/mortalidad , Neoplasias/terapia , ARN Guía de Kinetoplastida/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Receptores de Interferón/deficiencia , Receptores de Interferón/genética , Transducción de Señal/efectos de los fármacos , Factor 2 Asociado a Receptor de TNF/deficiencia , Factor 2 Asociado a Receptor de TNF/genética , Factor de Necrosis Tumoral alfa/farmacología , Receptor de Interferón gammaRESUMEN
Necrosis of infected macrophages constitutes a critical pathogenetic event in tuberculosis by releasing mycobacteria into the growth-permissive extracellular environment. In zebrafish infected with Mycobacterium marinum or Mycobacterium tuberculosis, excess tumor necrosis factor triggers programmed necrosis of infected macrophages through the production of mitochondrial reactive oxygen species (ROS) and the participation of cyclophilin D, a component of the mitochondrial permeability transition pore. Here, we show that this necrosis pathway is not mitochondrion-intrinsic but results from an inter-organellar circuit initiating and culminating in the mitochondrion. Mitochondrial ROS induce production of lysosomal ceramide that ultimately activates the cytosolic protein BAX. BAX promotes calcium flow from the endoplasmic reticulum into the mitochondrion through ryanodine receptors, and the resultant mitochondrial calcium overload triggers cyclophilin-D-mediated necrosis. We identify ryanodine receptors and plasma membrane L-type calcium channels as druggable targets to intercept mitochondrial calcium overload and necrosis of mycobacterium-infected zebrafish and human macrophages.
Asunto(s)
Macrófagos/microbiología , Macrófagos/patología , Mitocondrias/metabolismo , Infecciones por Mycobacterium no Tuberculosas/metabolismo , Tuberculosis/inmunología , Tuberculosis/patología , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Apoptosis , Calcio/metabolismo , Retículo Endoplásmico/microbiología , Humanos , Lisosomas/microbiología , Potencial de la Membrana Mitocondrial , Infecciones por Mycobacterium no Tuberculosas/patología , Mycobacterium marinum , Mycobacterium tuberculosis , Necrosis , Especies Reactivas de Oxígeno/metabolismo , Células THP-1 , Pez CebraRESUMEN
Growth and differentiation factor 15 (GDF15) is an inflammation-associated hormone with poorly defined biology. Here, we investigated the role of GDF15 in bacterial and viral infections. We found that inflammation induced GDF15, and that GDF15 was necessary for surviving both bacterial and viral infections, as well as sepsis. The protective effects of GDF15 were largely independent of pathogen control or the magnitude of inflammatory response, suggesting a role in disease tolerance. Indeed, we found that GDF15 was required for hepatic sympathetic outflow and triglyceride metabolism. Failure to defend the lower limit of plasma triglyceride levels was associated with impaired cardiac function and maintenance of body temperature, effects that could be rescued by exogenous administration of lipids. Together, we show that GDF15 coordinates tolerance to inflammatory damage through regulation of triglyceride metabolism.
Asunto(s)
Factor 15 de Diferenciación de Crecimiento/metabolismo , Hígado/metabolismo , Sepsis/patología , Animales , Anticuerpos/farmacología , Modelos Animales de Enfermedad , Factor 15 de Diferenciación de Crecimiento/sangre , Factor 15 de Diferenciación de Crecimiento/genética , Factor 15 de Diferenciación de Crecimiento/inmunología , Corazón/efectos de los fármacos , Corazón/virología , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Lipopolisacáridos/toxicidad , Hígado/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Norepinefrina/metabolismo , Orthomyxoviridae/patogenicidad , Poli I-C/toxicidad , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología , Sepsis/sangre , Sepsis/mortalidad , Tasa de Supervivencia , Triglicéridos/sangre , Triglicéridos/metabolismo , Troponina I/sangre , Factor de Necrosis Tumoral alfa/sangreRESUMEN
Sub-Saharan Africa currently experiences an unprecedented wave of urbanization, which has important consequences for health and disease patterns. This study aimed to investigate and integrate the immune and metabolic consequences of rural or urban lifestyles and the role of nutritional changes associated with urban living. In a cohort of 323 healthy Tanzanians, urban as compared to rural living was associated with a pro-inflammatory immune phenotype, both at the transcript and protein levels. We identified different food-derived and endogenous circulating metabolites accounting for these differences. Serum from urban dwellers induced reprogramming of innate immune cells with higher tumor necrosis factor production upon microbial re-stimulation in an in vitro model of trained immunity. These data demonstrate important shifts toward an inflammatory phenotype associated with an urban lifestyle and provide new insights into the underlying dietary and metabolic factors, which may affect disease epidemiology in sub-Sahara African countries.
Asunto(s)
Citocinas/sangre , Dieta Saludable , Metabolismo Energético , Inmunidad Innata , Mediadores de Inflamación/sangre , Salud Rural , Salud Urbana , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Citocinas/genética , Metabolismo Energético/genética , Femenino , Humanos , Inmunidad Innata/genética , Masculino , Metaboloma , Persona de Mediana Edad , Estado Nutricional , Valor Nutritivo , Conducta de Reducción del Riesgo , Estaciones del Año , Tanzanía , Transcriptoma , Factor de Necrosis Tumoral alfa/sangre , Urbanización , Adulto JovenRESUMEN
Misdirected immunity gives rise to the autoimmune tissue inflammation of rheumatoid arthritis, in which excess production of the cytokine tumor necrosis factor (TNF) is a central pathogenic event. Mechanisms underlying the breakdown of self-tolerance are unclear, but T cells in the arthritic joint have a distinctive metabolic signature of ATPlo acetyl-CoAhi proinflammatory effector cells. Here we show that a deficiency in the production of mitochondrial aspartate is an important abnormality in these autoimmune T cells. Shortage of mitochondrial aspartate disrupted the regeneration of the metabolic cofactor nicotinamide adenine dinucleotide, causing ADP deribosylation of the endoplasmic reticulum (ER) sensor GRP78/BiP. As a result, ribosome-rich ER membranes expanded, promoting co-translational translocation and enhanced biogenesis of transmembrane TNF. ERrich T cells were the predominant TNF producers in the arthritic joint. Transfer of intact mitochondria into T cells, as well as supplementation of exogenous aspartate, rescued the mitochondria-instructed expansion of ER membranes and suppressed TNF release and rheumatoid tissue inflammation.
Asunto(s)
Artritis Reumatoide/metabolismo , Ácido Aspártico/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Mitocondrias/metabolismo , Membrana Sinovial/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , ADP-Ribosilación , Traslado Adoptivo , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/inmunología , Artritis Reumatoide/patología , Autoinmunidad , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/trasplante , Linfocitos T CD4-Positivos/ultraestructura , Estudios de Casos y Controles , Células Cultivadas , Retículo Endoplásmico/inmunología , Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/ultraestructura , Chaperón BiP del Retículo Endoplásmico/metabolismo , Femenino , Humanos , Masculino , Ratones , Mitocondrias/inmunología , Mitocondrias/trasplante , Mitocondrias/ultraestructura , Membrana Sinovial/inmunología , Membrana Sinovial/ultraestructura , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Severe acute respiratory syndrome coronavirus 2 infections can cause coronavirus disease 2019 (COVID-19), which manifests with a range of severities from mild illness to life-threatening pneumonia and multi-organ failure. Severe COVID-19 is characterized by an inflammatory signature, including high levels of inflammatory cytokines, alveolar inflammatory infiltrates and vascular microthrombi. Here we show that patients with severe COVID-19 produced a unique serologic signature, including an increased likelihood of IgG1 with afucosylated Fc glycans. This Fc modification on severe acute respiratory syndrome coronavirus 2 IgGs enhanced interactions with the activating Fcγ receptor FcγRIIIa; when incorporated into immune complexes, Fc afucosylation enhanced production of inflammatory cytokines by monocytes, including interleukin-6 and tumor necrosis factor. These results show that disease severity in COVID-19 correlates with the presence of proinflammatory IgG Fc structures, including afucosylated IgG1.
Asunto(s)
COVID-19/inmunología , Citocinas/inmunología , Inmunoglobulina G/inmunología , Receptores de IgG/inmunología , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , COVID-19/metabolismo , COVID-19/virología , Niño , Citocinas/metabolismo , Femenino , Glicosilación , Humanos , Inmunoglobulina G/metabolismo , Interleucina-6 , Masculino , Persona de Mediana Edad , Receptores de IgG/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiología , Índice de Severidad de la Enfermedad , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
A new solid-state NMR study determines the high-resolution hetero-amyloid structure of the RIPK1-RIPK3 signaling complex that is involved in mediating necroptosis. The structure demonstrates specific formation of hetero-amyloids over homo-amyloids and the structural basis for a functional amyloid to act as a platform to recruit and activate downstream partners in intracellular signaling.
Asunto(s)
Necrosis , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Proteínas Amiloidogénicas , Apoptosis , Humanos , Transducción de Señal , Factor de Necrosis Tumoral alfaRESUMEN
In the healthy adult liver, most hepatocytes proliferate minimally. However, upon physical or chemical injury to the liver, hepatocytes proliferate extensively in vivo under the direction of multiple extracellular cues, including Wnt and pro-inflammatory signals. Currently, liver organoids can be generated readily in vitro from bile-duct epithelial cells, but not hepatocytes. Here, we show that TNFα, an injury-induced inflammatory cytokine, promotes the expansion of hepatocytes in 3D culture and enables serial passaging and long-term culture for more than 6 months. Single-cell RNA sequencing reveals broad expression of hepatocyte markers. Strikingly, in vitro-expanded hepatocytes engrafted, and significantly repopulated, the injured livers of Fah-/- mice. We anticipate that tissue repair signals can be harnessed to promote the expansion of otherwise hard-to-culture cell-types, with broad implications.
Asunto(s)
Antígenos de Diferenciación/biosíntesis , Técnicas de Cultivo de Célula , Proliferación Celular/efectos de los fármacos , Hepatocitos/metabolismo , Esferoides Celulares/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Animales , Línea Celular Transformada , Células Hep G2 , Hepatocitos/trasplante , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hígado/lesiones , Hígado/metabolismo , Ratones Noqueados , Esferoides Celulares/trasplante , Factores de TiempoRESUMEN
Many tumors produce platelet-derived growth factor (PDGF)-DD, which promotes cellular proliferation, epithelial-mesenchymal transition, stromal reaction, and angiogenesis through autocrine and paracrine PDGFRß signaling. By screening a secretome library, we found that the human immunoreceptor NKp44, encoded by NCR2 and expressed on natural killer (NK) cells and innate lymphoid cells, recognizes PDGF-DD. PDGF-DD engagement of NKp44 triggered NK cell secretion of interferon gamma (IFN)-γ and tumor necrosis factor alpha (TNF-α) that induced tumor cell growth arrest. A distinctive transcriptional signature of PDGF-DD-induced cytokines and the downregulation of tumor cell-cycle genes correlated with NCR2 expression and greater survival in glioblastoma. NKp44 expression in mouse NK cells controlled the dissemination of tumors expressing PDGF-DD more effectively than control mice, an effect enhanced by blockade of the inhibitory receptor CD96 or CpG-oligonucleotide treatment. Thus, while cancer cell production of PDGF-DD supports tumor growth and stromal reaction, it concomitantly activates innate immune responses to tumor expansion.