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1.
J Immunother Cancer ; 12(4)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663935

RESUMO

We describe three cases of critical acute myositis with myocarditis occurring within 22 days of each other at a single institution, all within 1 month of receiving the initial cycle of the anti-PD-1 drug pembrolizumab. Analysis of T cell receptor repertoires from peripheral blood and tissues revealed a high degree of clonal expansion and public clones between cases, with several T cell clones expanded within the skeletal muscle putatively recognizing viral epitopes. All patients had recently received a COVID-19 mRNA booster vaccine prior to treatment and were positive for SARS-CoV2 Spike antibody. In conclusion, we report a series of unusually severe myositis and myocarditis following PD-1 blockade and the COVID-19 mRNA vaccination.


Assuntos
Anticorpos Monoclonais Humanizados , COVID-19 , Miocardite , Miosite , SARS-CoV-2 , Idoso , Feminino , Humanos , Masculino , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/prevenção & controle , COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Miocardite/induzido quimicamente , Miosite/induzido quimicamente , SARS-CoV-2/imunologia , Vacinação/efeitos adversos , Idoso de 80 Anos ou mais
2.
Cell Rep ; 43(3): 113816, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38393946

RESUMO

Tight regulation of macrophage immune gene expression is required to fight infection without risking harmful inflammation. The contribution of RNA-binding proteins (RBPs) to shaping the macrophage response to pathogens remains poorly understood. Transcriptomic analysis reveals that a member of the serine/arginine-rich (SR) family of mRNA processing factors, SRSF7, is required for optimal expression of a cohort of interferon-stimulated genes in macrophages. Using genetic and biochemical assays, we discover that in addition to its canonical role in regulating alternative splicing, SRSF7 drives transcription of interferon regulatory transcription factor 7 (IRF7) to promote antiviral immunity. At the Irf7 promoter, SRSF7 maximizes STAT1 transcription factor binding and RNA polymerase II elongation via cooperation with the H4K20me1 histone methyltransferase KMT5a (SET8). These studies define a role for an SR protein in activating transcription and reveal an RBP-chromatin network that orchestrates macrophage antiviral gene expression.


Assuntos
Interferon Tipo I , Humanos , Transcrição Gênica , Regiões Promotoras Genéticas/genética , Macrófagos , Fatores de Processamento de RNA , Processamento Alternativo/genética , Fatores de Processamento de Serina-Arginina/genética
3.
Proc Natl Acad Sci U S A ; 121(9): e2312587121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38381785

RESUMO

To ensure a robust immune response to pathogens without risking immunopathology, the kinetics and amplitude of inflammatory gene expression in macrophages need to be exquisitely well controlled. There is a growing appreciation for stress-responsive membraneless organelles (MLOs) regulating various steps of eukaryotic gene expression in response to extrinsic cues. Here, we implicate the nuclear paraspeckle, a highly ordered biomolecular condensate that nucleates on the Neat1 lncRNA, in tuning innate immune gene expression in murine macrophages. In response to a variety of innate agonists, macrophage paraspeckles rapidly aggregate (0.5 h poststimulation) and disaggregate (2 h poststimulation). Paraspeckle maintenance and aggregation require active transcription and MAPK signaling, whereas paraspeckle disaggregation requires degradation of Neat1 via the nuclear RNA exosome. In response to lipopolysaccharide treatment, Neat1 KO macrophages fail to properly express a large cohort of proinflammatory cytokines, chemokines, and antimicrobial mediators. Consequently, Neat1 KO macrophages cannot control replication of Salmonella enterica serovar Typhimurium or vesicular stomatitis virus. These findings highlight a prominent role for MLOs in orchestrating the macrophage response to pathogens and support a model whereby dynamic assembly and disassembly of paraspeckles reorganizes the nuclear landscape to enable inflammatory gene expression following innate stimuli.


Assuntos
Paraspeckles , RNA Longo não Codificante , Humanos , Animais , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Macrófagos/metabolismo
4.
PLoS Pathog ; 19(6): e1011088, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37352334

RESUMO

Macrophages employ an array of pattern recognition receptors to detect and eliminate intracellular pathogens that access the cytosol. The cytosolic carbohydrate sensors Galectin-3, -8, and -9 (Gal-3, Gal-8, and Gal-9) recognize damaged pathogen-containing phagosomes, and Gal-3 and Gal-8 are reported to restrict bacterial growth via autophagy in cultured cells. However, the contribution of these galectins to host resistance during bacterial infection in vivo remains unclear. We found that Gal-9 binds directly to Mycobacterium tuberculosis (Mtb) and Salmonella enterica serovar Typhimurium (Stm) and localizes to Mtb in macrophages. To determine the combined contribution of membrane damage-sensing galectins to immunity, we generated Gal-3, -8, and -9 triple knockout (TKO) mice. Mtb infection of primary macrophages from TKO mice resulted in defective autophagic flux but normal bacterial replication. Surprisingly, these mice had no discernable defect in resistance to acute infection with Mtb, Stm or Listeria monocytogenes, and had only modest impairments in bacterial growth restriction and CD4 T cell activation during chronic Mtb infection. Collectively, these findings indicate that while Gal-3, -8, and -9 respond to an array of intracellular pathogens, together these membrane damage-sensing galectins play a limited role in host resistance to bacterial infection.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Camundongos , Animais , Galectina 3/genética , Tuberculose/metabolismo , Galectinas/genética , Galectinas/metabolismo , Macrófagos , Salmonella typhimurium , Camundongos Knockout
5.
Otol Neurotol ; 44(7): 664-671, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37278159

RESUMO

OBJECTIVE: To describe the development, implementation, and validation of a radiology-administered protocol to obtain magnetic resonance imaging (MRI) in patients with cochlear implants and auditory brainstem implants without magnet removal. STUDY DESIGN: Retrospective review and description of novel care pathway. METHODS: A radiology-administered protocol was designed based on careful input from the radiology safety committee and neurotology. Radiology technologist training modules, consent instructions, patient educational material, clinical audits, and other safeguards were implemented, with samples provided in this report. The primary outcomes measured included instances of magnet displacement during MRI and premature termination of MRI studies secondary to pain. RESULTS: Between June 19, 2018, and October 12, 2021, 301 implanted ears underwent MRI without magnet removal, including 153 devices housing diametric MRI-conditional magnets, and 148 implants with conventional axial (i.e., nondiametric) magnets. Among cases with diametric MRI-conditional magnets, all studies were completed without magnet dislodgement or need to terminate imaging early due to pain. Among cases with conventional axial (nondiametric) magnets, 29 (19.6%) MRI studies were stopped prematurely secondary to pain or discomfort; the overall rate of this event was 9.6% (29 of 301) among the entire study cohort. In addition, 6.1% (9 of 148) experienced confirmed magnet displacement despite headwrap placement; the overall rate among all cases was 3.0% (9 of 301). Eight of these patients received successful external magnet reseating through manual pressure on the external scalp without surgery, and one required surgical replacement of the magnet in the operating room. There were no documented instances of hematoma, infection, device or magnet extrusion, internal device movement (i.e., gross receiver-stimulator migration), or device malfunction in this cohort related to MRI. CONCLUSIONS: We present the successful implementation of a radiology-administered protocol designed to streamline care for cochlear implant and auditory brainstem implant recipients who require MRI and ease clinical demands for otolaryngology providers. Examples of resources developed, including a process map, radiology training modules, consent instructions, patient educational materials, clinical audit, and other procedural safety measures are provided so interested groups may consider adapting and implementing related measures according to need.


Assuntos
Implante Coclear , Implantes Cocleares , Radiologia , Humanos , Imãs , Fluxo de Trabalho , Imageamento por Ressonância Magnética/métodos
6.
Trends Cell Biol ; 33(9): 773-787, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37062616

RESUMO

Since their discovery, members of the gasdermin (GSDM) family of proteins have been firmly established as executors of pyroptosis, with the N-terminal fragment of most GSDMs capable of forming pores in the plasma membrane. More recent findings suggest that some GSDMs can drive additional cell death pathways, such as apoptosis and necroptosis, through mechanisms independent of plasma membrane perforation. There is also emerging evidence that by associating with cellular compartments such as mitochondria, peroxisomes, endosomes, and the nucleus, GSDMs regulate cell death-independent aspects of cellular homeostasis. Here, we review the diversity of GSDM function across several cell types and explore how various cellular stresses can promote relocalization - and thus refunctionalization - of GSDMs.


Assuntos
Gasderminas , Proteínas de Neoplasias , Humanos , Proteínas de Neoplasias/metabolismo , Apoptose , Piroptose/fisiologia , Homeostase , Inflamassomos/metabolismo
7.
Continuum (Minneap Minn) ; 29(1): 27-53, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36795872

RESUMO

OBJECTIVE: MRI and CT are indispensable imaging modalities for the evaluation of patients with neurologic disease, and each is particularly well suited to address specific clinical questions. Although both of these imaging modalities have excellent safety profiles in clinical use as a result of concerted and dedicated efforts, each has potential physical and procedural risks that the practitioner should be aware of, which are described in this article. LATEST DEVELOPMENTS: Recent advancements have been made in understanding and reducing safety risks with MR and CT. The magnetic fields in MRI create risks for dangerous projectile accidents, radiofrequency burns, and deleterious interactions with implanted devices, and serious patient injuries and deaths have occurred. Ionizing radiation in CT may be associated with shorter-term deterministic effects on biological tissues at extremely high doses and longer-term stochastic effects related to mutagenesis and carcinogenesis at low doses. The cancer risk of radiation exposure in diagnostic CT is considered extremely low, and the benefit of an appropriately indicated CT examination far outweighs the potential risk. Continuing major efforts are centered on improving image quality and the diagnostic power of CT while concurrently keeping radiation doses as low as reasonably achievable. ESSENTIAL POINTS: An understanding of these MRI and CT safety issues that are central to contemporary radiology practice is essential for the safe and effective treatment of patients with neurologic disease.


Assuntos
Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Risco , Tomografia Computadorizada por Raios X/efeitos adversos
8.
Nat Commun ; 14(1): 321, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658158

RESUMO

IFNγ is an immune mediator with concomitant pro- and anti-tumor functions. Here, we provide evidence that IFNγ directly acts on intra-tumoral CD8 T cells to restrict anti-tumor responses. We report that expression of the IFNγ receptor ß chain (IFNγR2) in CD8 T cells negatively correlates with clinical responsiveness to checkpoint blockade in metastatic melanoma patients, suggesting that the loss of sensitivity to IFNγ contributes to successful antitumor immunity. Indeed, specific deletion of IFNγR in CD8 T cells promotes tumor control in a mouse model of melanoma. Chronic IFNγ inhibits the maintenance, clonal diversity and proliferation of stem-like T cells. This leads to decreased generation of T cells with intermediate expression of exhaustion markers, previously associated with beneficial anti-tumor responses. This study provides evidence of a negative feedback loop whereby IFNγ depletes stem-like T cells to restrict anti-tumor immunity. Targeting this pathway might represent an alternative strategy to enhance T cell-based therapies.


Assuntos
Melanoma , Linfócitos T Citotóxicos , Camundongos , Animais , Linfócitos T Citotóxicos/metabolismo , Linfócitos T CD8-Positivos , Melanoma/terapia , Melanoma/tratamento farmacológico , Células Clonais/metabolismo
9.
Nat Med ; 28(12): 2592-2600, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36526722

RESUMO

Treatment with immune checkpoint blockade (ICB) frequently triggers immune-related adverse events (irAEs), causing considerable morbidity. In 214 patients receiving ICB for melanoma, we observed increased severe irAE risk in minor allele carriers of rs16906115, intronic to IL7. We found that rs16906115 forms a B cell-specific expression quantitative trait locus (eQTL) to IL7 in patients. Patients carrying the risk allele demonstrate increased pre-treatment B cell IL7 expression, which independently associates with irAE risk, divergent immunoglobulin expression and more B cell receptor mutations. Consistent with the role of IL-7 in T cell development, risk allele carriers have distinct ICB-induced CD8+ T cell subset responses, skewing of T cell clonality and greater proportional repertoire occupancy by large clones. Finally, analysis of TCGA data suggests that risk allele carriers independently have improved melanoma survival. These observations highlight key roles for B cells and IL-7 in both ICB response and toxicity and clinical outcomes in melanoma.


Assuntos
Interleucina-7 , Melanoma , Humanos , Interleucina-7/genética , Interleucina-7/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Melanoma/tratamento farmacológico , Melanoma/genética , Linfócitos T CD8-Positivos , Variação Genética
10.
Mayo Clin Proc ; 97(11): 2123-2138, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36210199

RESUMO

Permanently implanted devices that deliver electrical stimulation are increasingly used to treat patients with drug-resistant epilepsy. Primary care physicians, neurologists, and epilepsy clinicians may encounter patients with a variety of implanted neuromodulation devices in the course of clinical care. Due to the rapidly changing landscape of available epilepsy-related neurostimulators, there may be uncertainty related to how these devices should be handled during imaging procedures and perioperative care. We review the safety and management of epilepsy-related implanted neurostimulators that may be encountered during imaging and surgery. We provide a summary of approved device labeling and recommendations for the practical management of these devices to help guide clinicians as they care for patients treated with bioelectronic medicine.


Assuntos
Epilepsia , Humanos , Epilepsia/cirurgia , Epilepsia/etiologia , Neuroestimuladores Implantáveis , Assistência Perioperatória , Diagnóstico por Imagem
11.
BMC Biol ; 20(1): 182, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986286

RESUMO

BACKGROUND: SP140 is a bromodomain-containing protein expressed predominantly in immune cells. Genetic polymorphisms and epigenetic modifications in the SP140 locus have been linked to Crohn's disease (CD), suggesting a role in inflammation. RESULTS: We report the development of the first small molecule SP140 inhibitor (GSK761) and utilize this to elucidate SP140 function in macrophages. We show that SP140 is highly expressed in CD mucosal macrophages and in in vitro-generated inflammatory macrophages. SP140 inhibition through GSK761 reduced monocyte-to-inflammatory macrophage differentiation and lipopolysaccharide (LPS)-induced inflammatory activation, while inducing the generation of CD206+ regulatory macrophages that were shown to associate with a therapeutic response to anti-TNF in CD patients. SP140 preferentially occupies transcriptional start sites in inflammatory macrophages, with enrichment at gene loci encoding pro-inflammatory cytokines/chemokines and inflammatory pathways. GSK761 specifically reduces SP140 chromatin binding and thereby expression of SP140-regulated genes. GSK761 inhibits the expression of cytokines, including TNF, by CD14+ macrophages isolated from CD intestinal mucosa. CONCLUSIONS: This study identifies SP140 as a druggable epigenetic therapeutic target for CD.


Assuntos
Doença de Crohn , Inibidores do Fator de Necrose Tumoral , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Doença de Crohn/genética , Doença de Crohn/metabolismo , Citocinas/genética , Citocinas/metabolismo , Epigênese Genética , Humanos , Macrófagos , Fatores de Transcrição/genética
12.
Cell ; 185(17): 3214-3231.e23, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35907404

RESUMO

Although mutations in mitochondrial-associated genes are linked to inflammation and susceptibility to infection, their mechanistic contributions to immune outcomes remain ill-defined. We discovered that the disease-associated gain-of-function allele Lrrk2G2019S (leucine-rich repeat kinase 2) perturbs mitochondrial homeostasis and reprograms cell death pathways in macrophages. When the inflammasome is activated in Lrrk2G2019S macrophages, elevated mitochondrial ROS (mtROS) directs association of the pore-forming protein gasdermin D (GSDMD) to mitochondrial membranes. Mitochondrial GSDMD pore formation then releases mtROS, promoting a switch to RIPK1/RIPK3/MLKL-dependent necroptosis. Consistent with enhanced necroptosis, infection of Lrrk2G2019S mice with Mycobacterium tuberculosis elicits hyperinflammation and severe immunopathology. Our findings suggest a pivotal role for GSDMD as an executer of multiple cell death pathways and demonstrate that mitochondrial dysfunction can direct immune outcomes via cell death modality switching. This work provides insights into how LRRK2 mutations manifest or exacerbate human diseases and identifies GSDMD-dependent necroptosis as a potential target to limit Lrrk2G2019S-mediated immunopathology.


Assuntos
Mitocôndrias , Necroptose , Proteínas de Ligação a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Animais , Humanos , Inflamassomos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Macrófagos , Camundongos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
13.
Paediatr Anaesth ; 32(8): 899-906, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35426458

RESUMO

BACKGROUND: Pain may be a modifiable risk factor for lower health-related quality of life after pediatric critical illness. AIM: To evaluate the association between severe pain experienced in the (pediatrc intensive care unit) and postdischarge health-related quality of life. METHODS: This was a retrospective cohort study. Children aged 1 month to 18 years admitted to the pediatric intensive care unit and enrolled in the Seattle Children's Hospital Outcomes Assessment Program were included. Pain was assessed every 2 h by bedside nursing staff using a behavioral pain scale or numeric pain scale. A day of severe pain was defined as a pediatric intensive care unit day with ≥25% of pain scores ≥7/10. Baseline (preadmission) and postdischarge (median 6 weeks) health-related quality of life was assessed by the Pediatric Quality of Life Inventory (PedsQL™) or the Stein Jessop Functional Status II-R (FS II-R, for children with developmental disability). The cohort was stratified by diagnosis category (surgical vs. medical), and associations were measured using linear regression models. RESULTS: Among 546 patients, 11.9% experienced ≥1 day of severe pain. In multivariable linear regression, each day of severe pain was independently associated with a lower postdischarge health-related quality of life score by 3.6 points (95% CI -6.3 to -0.9) adjusted for baseline health-related quality of life score, age, baseline cognitive function, days with multi-organ dysfunction, pediatric intensive care unit length of stay, and decline in overall function. This association was stronger among surgical patients than medical patients with each day of severe pain resulting in a lower postdischarge health-related quality of life score by 5.3 points (95% CI -9.6 to -0.9) versus 2.6 points (95% CI -5.8 to 0.6). Surgical patients had lower postdischarge emotional functioning than physical functioning subdomain scores. CONCLUSIONS: Children who experience severe pain in the pediatric intensive care unit have lower postdischarge health-related quality of life adjusting for baseline health-related quality of life, particularly among children who have undergone surgery. Attention to pain management may be important to improve postdischarge health-related quality of life.


Assuntos
Assistência ao Convalescente , Qualidade de Vida , Criança , Estudos de Coortes , Humanos , Unidades de Terapia Intensiva Pediátrica , Dor , Alta do Paciente , Estudos Retrospectivos
14.
J Med Chem ; 65(3): 2262-2287, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-34995458

RESUMO

Through regulation of the epigenome, the bromodomain and extra terminal (BET) family of proteins represent important therapeutic targets for the treatment of human disease. Through mimicking the endogenous N-acetyl-lysine group and disrupting the protein-protein interaction between histone tails and the bromodomain, several small molecule pan-BET inhibitors have progressed to oncology clinical trials. This work describes the medicinal chemistry strategy and execution to deliver an orally bioavailable tetrahydroquinoline (THQ) pan-BET candidate. Critical to the success of this endeavor was a potency agnostic analysis of a data set of 1999 THQ BET inhibitors within the GSK collection which enabled identification of appropriate lipophilicity space to deliver compounds with a higher probability of desired oral candidate quality properties. SAR knowledge was leveraged via Free-Wilson analysis within this design space to identify a small group of targets which ultimately delivered I-BET567 (27), a pan-BET candidate inhibitor that demonstrated efficacy in mouse models of oncology and inflammation.


Assuntos
Aminoquinolinas/química , Desenho de Fármacos , Proteínas/metabolismo , Administração Oral , Aminoquinolinas/metabolismo , Aminoquinolinas/farmacocinética , Aminoquinolinas/uso terapêutico , Animais , Benzoatos/química , Benzoatos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Cães , Meia-Vida , Humanos , Masculino , Camundongos , Conformação Molecular , Simulação de Dinâmica Molecular , Neoplasias/tratamento farmacológico , Proteínas/antagonistas & inibidores , Ratos , Relação Estrutura-Atividade
15.
Sci Immunol ; 6(64): eabj8825, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34597125

RESUMO

The antitumor action of immune checkpoint blockade (ICB) is primarily mediated by CD8+ T cells. How sensitivity to ICB varies across CD8+ T cell subsets and clonotypes and the relationship of these with clinical outcome is unclear. To explore this, we used single-cell V(D)J and RNA-sequencing to track gene expression changes elicited by ICB across individual peripheral CD8+ T cell clones, identify baseline markers of CD8+ T cell clonal sensitivity, and chart how CD8+ T cell transcriptional changes vary according to phenotypic subset and clonal size. We identified seven subsets of CD8+ T cells with divergent reactivity to ICB and found that the cytotoxic effector subset showed the greatest number of differentially expressed genes while remaining stable in clonal size after ICB. At the level of CD8+ T cell clonotypes, we found a relationship between transcriptional changes and clone size, with large clones showing a greater number of differentially regulated genes enriched for pathways including T cell receptor (TCR) signaling. Cytotoxic CD8+ effector clones were more likely to persist following ICB and were more likely to correspond with public tumor-infiltrating lymphocyte clonotypes. Last, we demonstrated that individuals whose CD8+ T cell pretreatment showed low cytotoxicity and had fewer expanded clones typically had worse outcomes after ICB treatment. This work further advances understanding of the molecular determinants of ICB response, assisting in the search for peripheral prognostic biomarkers and highlighting the importance of the baseline CD8+ immune landscape in determining ICB response in metastatic melanoma.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Ipilimumab/farmacologia , Nivolumabe/farmacologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Intervalo Livre de Progressão
16.
PLoS Pathog ; 17(9): e1009888, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34473814

RESUMO

Rhodococcus equi is a major cause of foal pneumonia and an opportunistic pathogen in immunocompromised humans. While alveolar macrophages constitute the primary replicative niche for R. equi, little is known about how intracellular R. equi is sensed by macrophages. Here, we discovered that in addition to previously characterized pro-inflammatory cytokines (e.g., Tnfa, Il6, Il1b), macrophages infected with R. equi induce a robust type I IFN response, including Ifnb and interferon-stimulated genes (ISGs), similar to the evolutionarily related pathogen, Mycobacterium tuberculosis. Follow up studies using a combination of mammalian and bacterial genetics demonstrated that induction of this type I IFN expression program is largely dependent on the cGAS/STING/TBK1 axis of the cytosolic DNA sensing pathway, suggesting that R. equi perturbs the phagosomal membrane and causes DNA release into the cytosol following phagocytosis. Consistent with this, we found that a population of ~12% of R. equi phagosomes recruits the galectin-3,-8 and -9 danger receptors. Interestingly, neither phagosomal damage nor induction of type I IFN require the R. equi's virulence-associated plasmid. Importantly, R. equi infection of both mice and foals stimulates ISG expression, in organs (mice) and circulating monocytes (foals). By demonstrating that R. equi activates cytosolic DNA sensing in macrophages and elicits type I IFN responses in animal models, our work provides novel insights into how R. equi engages the innate immune system and furthers our understanding how this zoonotic pathogen causes inflammation and disease.


Assuntos
Infecções por Actinomycetales/imunologia , Imunidade Inata/imunologia , Interferon Tipo I/imunologia , Macrófagos/imunologia , Rhodococcus equi/imunologia , Animais , Citosol/imunologia , DNA/imunologia , Feminino , Doenças dos Cavalos/imunologia , Cavalos , Masculino , Camundongos
17.
J Med Chem ; 64(16): 12200-12227, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34387088

RESUMO

The functions of the bromodomain and extra terminal (BET) family of proteins have been implicated in a wide range of diseases, particularly in the oncology and immuno-inflammatory areas, and several inhibitors are under investigation in the clinic. To mitigate the risk of attrition of these compounds due to structurally related toxicity findings, additional molecules from distinct chemical series were required. Here we describe the structure- and property-based optimization of the in vivo tool molecule I-BET151 toward I-BET282E, a molecule with properties suitable for progression into clinical studies.


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite/tratamento farmacológico , Imidazóis/uso terapêutico , Proteínas Nucleares/antagonistas & inibidores , Quinolinas/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/metabolismo , Artrite/induzido quimicamente , Colágeno , Cristalografia por Raios X , Cães , Feminino , Imidazóis/síntese química , Imidazóis/metabolismo , Masculino , Camundongos , Estrutura Molecular , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Ligação Proteica , Domínios Proteicos , Quinolinas/síntese química , Quinolinas/metabolismo , Ratos Endogâmicos Lew , Ratos Wistar , Relação Estrutura-Atividade , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
18.
Front Immunol ; 12: 656885, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305890

RESUMO

Pathogen sensing via pattern recognition receptors triggers massive reprogramming of macrophage gene expression. While the signaling cascades and transcription factors that activate these responses are well-known, the role of post-transcriptional RNA processing in modulating innate immune gene expression remains understudied. Given their crucial role in regulating pre-mRNA splicing and other RNA processing steps, we hypothesized that members of the SR/hnRNP protein families regulate innate immune gene expression in distinct ways. We analyzed steady state gene expression and alternatively spliced isoform production in ten SR/hnRNP knockdown RAW 264.7 macrophage-like cell lines following infection with the bacterial pathogen Salmonella enterica serovar Typhimurium (Salmonella). We identified thousands of transcripts whose abundance is increased or decreased by SR/hnRNP knockdown in macrophages. Notably, we observed that SR and hnRNP proteins influence expression of different genes in uninfected versus Salmonella-infected macrophages, suggesting functionalization of these proteins upon pathogen sensing. Likewise, we found that knockdown of SR/hnRNPs promoted differential isoform usage (DIU) for thousands of macrophage transcripts and that these alternative splicing changes were distinct in uninfected and Salmonella-infected macrophages. Finally, having observed a surprising degree of similarity between the differentially expressed genes (DEGs) and DIUs in hnRNP K and U knockdown macrophages, we found that hnRNP K and U knockdown macrophages are both more restrictive to Vesicular Stomatitis Virus (VSV), while hnRNP K knockdown macrophages are more permissive to Salmonella Typhimurium. Based on these findings, we conclude that many innate immune genes evolved to rely on one or more SR/hnRNPs to ensure the proper magnitude of their induction, supporting a model wherein pre-mRNA splicing is critical for regulating innate immune gene expression and controlling infection outcomes in macrophages ex vivo.


Assuntos
Processamento Alternativo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Imunidade Inata/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Transcriptoma , Animais , Biomarcadores , Biologia Computacional/métodos , Ontologia Genética , Redes Reguladoras de Genes , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Masculino , Camundongos , Modelos Biológicos , Células RAW 264.7 , Infecções por Salmonella/genética , Infecções por Salmonella/imunologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/imunologia
19.
J Med Chem ; 64(15): 10772-10805, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34255512

RESUMO

The profound efficacy of pan-BET inhibitors is well documented, but these epigenetic agents have shown pharmacology-driven toxicity in oncology clinical trials. The opportunity to identify inhibitors with an improved safety profile by selective targeting of a subset of the eight bromodomains of the BET family has triggered extensive medicinal chemistry efforts. In this article, we disclose the identification of potent and selective drug-like pan-BD2 inhibitors such as pyrazole 23 (GSK809) and furan 24 (GSK743) that were derived from the pyrrole fragment 6. We transpose the key learnings from a previous pyridone series (GSK620 2 as a representative example) to this novel class of inhibitors, which are characterized by significantly improved solubility relative to our previous research.


Assuntos
Furanos/farmacologia , Proteínas/antagonistas & inibidores , Pirazóis/farmacologia , Relação Dose-Resposta a Droga , Furanos/química , Humanos , Estrutura Molecular , Proteínas/metabolismo , Pirazóis/química , Relação Estrutura-Atividade
20.
mBio ; 12(4): e0187120, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34225486

RESUMO

Mycobacterium tuberculosis (Mtb) causes one of the deadliest infectious diseases worldwide. Upon infection, Mtb is phagocytosed by macrophages and uses its virulence-associated ESX-1 secretion system to modulate the host cell. We showed previously that the ESX-1 secretion system perturbs the Mtb-containing phagosome, and a population (∼30%) of intracellular Mtb is tagged with ubiquitin and targeted to selective autophagy. However, our understanding of how macrophages sense and respond to damaged Mtb-containing phagosomes remains incomplete. Here, we demonstrate that several cytosolic glycan-binding proteins called galectins recognize Mtb-containing phagosomes; in macrophage cell lines and in primary macrophages, galectin-3, -8, and -9 are all recruited to the same Mtb population that colocalizes with selective autophagy markers (ubiquitin, p62, and LC3). To test whether galectins are required for controlling Mtb replication in macrophages, we generated CRISPR/Cas9 knockouts and found that galectin-8-/- and galectin-3/8/9-/- macrophages were similarly defective in targeting Mtb to selective autophagy and controlling replication. This suggests galectin-8 plays a unique role in anti-Mtb autophagy. In investigating galectin-8's role, we identified a novel and specific interaction between galectin-8 and the selective autophagy adapter TAX1BP1 and found that this galectin-8/TAX1BP1 interaction was necessary for macrophages to efficiently target Mtb to selective autophagy. Remarkably, overexpressing galectin-8 increased targeting of Mtb to autophagy and limited Mtb replication. Taken together, these data demonstrate that while several galectins are capable of recognizing damaged Mtb-containing phagosomes, galectin-8 plays a privileged role in recruiting downstream autophagy machinery and may represent a promising target for host-directed tuberculosis therapies. IMPORTANCE Mycobacterium tuberculosis (Mtb) infects one-quarter of the global population and causes one of the deadliest infectious diseases worldwide. Macrophages are the first line of defense against Mtb infection and are typically incredibly efficient at destroying intracellular pathogens, but Mtb has evolved to survive and replicate in this harsh environment. Previous work has found that a portion of intracellular Mtb bacilli damage their phagosomes, leaving them vulnerable to detection by the host and delivery to an antibacterial pathway called selective autophagy. Here, we show that in macrophages, galectin-8 recognizes damaged Mtb-containing phagosomes and targets Mtb to selective autophagy; we found that galectin-8, unlike other highly similar and closely related galectins, is required for targeting and controlling Mtb in macrophages. The specific role for galectin-8 appears to stem from its interaction with TAX1BP1, a selective autophagy adapter protein. Interestingly, overexpressing galectin-8 helps macrophages target and control Mtb, highlighting the importance of galectin-8 in the innate immune response to Mtb.


Assuntos
Autofagia , Galectinas/genética , Imunidade Inata , Peptídeos e Proteínas de Sinalização Intracelular/genética , Macrófagos/microbiologia , Proteínas de Neoplasias/genética , Fagossomos/microbiologia , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Galectinas/imunologia , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Macrófagos/imunologia , Camundongos , Proteínas de Neoplasias/imunologia , Fagocitose , Células RAW 264.7 , Células U937
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