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1.
Front Immunol ; 11: 606456, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329603

RESUMO

For several decades there has been accumulating evidence implicating type I interferons (IFNs) as key elements of the immune response. Therapeutic approaches incorporating different recombinant type I IFN proteins have been successfully employed to treat a diverse group of diseases with significant and positive outcomes. The biological activities of type I IFNs are consequences of signaling events occurring in the cytoplasm and nucleus of cells. Biochemical events involving JAK/STAT proteins that control transcriptional activation of IFN-stimulated genes (ISGs) were the first to be identified and are referred to as "canonical" signaling. Subsequent identification of JAK/STAT-independent signaling pathways, critical for ISG transcription and/or mRNA translation, are denoted as "non-canonical" or "non-classical" pathways. In this review, we summarize these signaling cascades and discuss recent developments in the field, specifically as they relate to the biological and clinical implications of engagement of both canonical and non-canonical pathways.


Assuntos
Interferon Tipo I/imunologia , Biossíntese de Proteínas/imunologia , Transdução de Sinais/imunologia , Transcrição Genética/imunologia , Animais , Humanos , Janus Quinases/imunologia , Fatores de Transcrição STAT/imunologia
2.
PLoS Pathog ; 16(9): e1008821, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32941545

RESUMO

MHC-I-restricted, virus-specific cytotoxic CD8+ T cells (CTLs) may control human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) replication via the recognition and killing of productively infected CD4+ T cells. Several studies in SIV-infected macaques suggest that CD8+ T cells may also decrease virus production by suppressing viral transcription. Here, we show that non-HIV-specific, TCR-activated non-cytolytic CD8+ T cells suppress HIV transcription via a virus- and MHC-independent immunoregulatory mechanism that modulates CD4+ T cell proliferation and activation. We also demonstrate that this CD8+ T cell-mediated effect promotes the survival of infected CD4+ T cells harboring integrated, inducible virus. Finally, we used RNA sequencing and secretome analyses to identify candidate cellular pathways that are involved in the virus-silencing mediated by these CD8+ T cells. This study characterizes a previously undescribed mechanism of immune-mediated HIV silencing that may be involved in the establishment and maintenance of the reservoir under antiretroviral therapy and therefore represent a major obstacle to HIV eradication.


Assuntos
Linfócitos T CD8-Positivos/imunologia , HIV-1/fisiologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunidade Inata , Transcrição Genética/imunologia , Replicação Viral/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Proliferação de Células , Humanos , Macaca
3.
Cells ; 9(9)2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847031

RESUMO

Following influenza infection, rs2248374-G ERAP2 expressing cells may transcribe an alternative spliced isoform: ERAP2/Iso3. This variant, unlike ERAP2-wt, is unable to trim peptides to be loaded on MHC class I molecules, but it can still dimerize with both ERAP2-wt and ERAP1-wt, thus contributing to profiling an alternative cellular immune-peptidome. In order to verify if the expression of ERAP2/Iso3 may be induced by other pathogens, PBMCs and MDMs isolated from 20 healthy subjects were stimulated with flu, LPS, CMV, HIV-AT-2, SARS-CoV-2 antigens to analyze its mRNA and protein expression. In parallel, Calu3 cell lines and PBMCs were in vitro infected with growing doses of SARS-CoV-2 (0.5, 5, 1000 MOI) and HIV-1BAL (0.1, 1, and 10 ng p24 HIV-1Bal/1 × 106 PBMCs) viruses, respectively. Results showed that: (1) ERAP2/Iso3 mRNA expression can be prompted by many pathogens and it is coupled with the modulation of several determinants (cytokines, interferon-stimulated genes, activation/inhibition markers, antigen-presentation elements) orchestrating the anti-microbial immune response (Quantigene); (2) ERAP2/Iso3 mRNA is translated into a protein (western blot); (3) ERAP2/Iso3 mRNA expression is sensitive to SARS-CoV-2 and HIV-1 concentration. Considering the key role played by ERAPs in antigen processing and presentation, it is conceivable that these enzymes may be potential targets and modulators of the pathogenicity of infectious diseases and further analyses are needed to define the role played by the different isoforms.


Assuntos
Aminopeptidases/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/genética , Imunização/métodos , Leucócitos Mononucleares/virologia , Macrófagos/virologia , Pneumonia Viral/genética , Isoformas de Proteínas/genética , Apresentação do Antígeno/genética , Doadores de Sangue , Linhagem Celular Tumoral , Infecções por Coronavirus/virologia , Expressão Gênica/imunologia , Genótipo , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Pandemias , Pneumonia Viral/virologia , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Genética/imunologia
4.
Nucleic Acids Res ; 48(16): 9204-9217, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32766806

RESUMO

The type III CRISPR-Cas systems provide immunity against invading nucleic acids through the coordinated transcription-dependent DNA targeting and cyclic adenylate (cAn)-activated RNA degradation. Here, we show that both these pathways contribute to the Streptococcus thermophilus (St) type III-A CRISPR-Cas immunity. HPLC-MS analysis revealed that in the heterologous Escherichia coli host the StCsm effector complex predominantly produces cA5 and cA6. cA6 acts as a signaling molecule that binds to the CARF domain of StCsm6 to activate non-specific RNA degradation by the HEPN domain. By dissecting StCsm6 domains we demonstrate that both CARF and HEPN domains act as ring nucleases that degrade cAns to switch signaling off. CARF ring nuclease converts cA6 to linear A6>p and to the final A3>p product. HEPN domain, which typically degrades RNA, also shows ring nuclease activity and indiscriminately degrades cA6 or other cAns down to A>p. We propose that concerted action of both ring nucleases enables self-regulation of the RNase activity in the HEPN domain and eliminates all cAn secondary messengers in the cell when viral infection is combated by a coordinated action of Csm effector and the cA6-activated Csm6 ribonuclease.


Assuntos
Sistemas CRISPR-Cas/genética , Imunidade/genética , Streptococcus thermophilus/genética , Transcrição Genética/genética , Cromatografia Líquida de Alta Pressão , Endonucleases/genética , Escherichia coli/genética , Escherichia coli/imunologia , Domínios Proteicos/genética , Estabilidade de RNA/genética , Estabilidade de RNA/imunologia , Ribonucleases/genética , Transdução de Sinais/genética , Streptococcus thermophilus/imunologia , Transcrição Genética/imunologia
5.
Nature ; 583(7815): 296-302, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612232

RESUMO

The mammalian immune system implements a remarkably effective set of mechanisms for fighting pathogens1. Its main components are haematopoietic immune cells, including myeloid cells that control innate immunity, and lymphoid cells that constitute adaptive immunity2. However, immune functions are not unique to haematopoietic cells, and many other cell types display basic mechanisms of pathogen defence3-5. To advance our understanding of immunology outside the haematopoietic system, here we systematically investigate the regulation of immune genes in the three major types of structural cells: epithelium, endothelium and fibroblasts. We characterize these cell types across twelve organs in mice, using cellular phenotyping, transcriptome sequencing, chromatin accessibility profiling and epigenome mapping. This comprehensive dataset revealed complex immune gene activity and regulation in structural cells. The observed patterns were highly organ-specific and seem to modulate the extensive interactions between structural cells and haematopoietic immune cells. Moreover, we identified an epigenetically encoded immune potential in structural cells under tissue homeostasis, which was triggered in response to systemic viral infection. This study highlights the prevalence and organ-specific complexity of immune gene activity in non-haematopoietic structural cells, and it provides a high-resolution, multi-omics atlas of the epigenetic and transcriptional networks that regulate structural cells in the mouse.


Assuntos
Endotélio/imunologia , Células Epiteliais/imunologia , Fibroblastos/imunologia , Regulação da Expressão Gênica/imunologia , Sistema Imunitário/citologia , Sistema Imunitário/imunologia , Especificidade de Órgãos/imunologia , Imunidade Adaptativa , Animais , Cromatina/genética , Cromatina/metabolismo , Endotélio/citologia , Epigênese Genética/imunologia , Epigenoma/genética , Células Epiteliais/citologia , Feminino , Fibroblastos/citologia , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/imunologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Sistema Imunitário/virologia , Imunidade Inata , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/imunologia , Masculino , Camundongos , Especificidade de Órgãos/genética , Transcrição Genética/imunologia , Transcriptoma/genética
6.
Proc Natl Acad Sci U S A ; 117(25): 14354-14364, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513697

RESUMO

Ischemic injury initiates a sterile inflammatory response that ultimately participates in the repair and recovery of tissue perfusion. Macrophages are required for perfusion recovery during ischemia, in part because they produce growth factors that aid in vascular remodeling. The input signals governing this pro-revascularization phenotype remain of interest. Here we found that hindlimb ischemia increases levels of resolvin D1 (RvD1), an inflammation-resolving lipid mediator that targets macrophages via its receptor, ALX/FPR2. Exogenous RvD1 enhances perfusion recovery during ischemia, and mice deficient in Alx/Fpr2 have an endogenous defect in this process. Mechanistically, RNA sequencing revealed that RvD1 induces a transcriptional program in macrophages characteristic of a pro-revascularization phenotype. Vascularization of ischemic skeletal muscle, as well as cutaneous wounds, is impaired in mice with myeloid-specific deficiency of Alx/Fpr2, and this is associated with altered expression of pro-revascularization genes in skeletal muscle and macrophages isolated from skeletal muscle. Collectively, these results uncover a role of ALX/FPR2 in revascularization that may be amenable to therapeutic targeting in diseases associated with altered tissue perfusion and repair.


Assuntos
Ácidos Docosa-Hexaenoicos/metabolismo , Isquemia/imunologia , Neovascularização Fisiológica/imunologia , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo , Cicatrização/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Isquemia/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/imunologia , Músculo Esquelético/patologia , Cultura Primária de Células , RNA-Seq , Receptores de Formil Peptídeo/genética , Receptores de Lipoxinas/genética , Transdução de Sinais/imunologia , Pele/irrigação sanguínea , Pele/imunologia , Pele/lesões , Pele/patologia , Transcrição Genética/imunologia
7.
Immunity ; 52(5): 825-841.e8, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32396847

RESUMO

CD8+ T cell exhaustion is a major barrier to current anti-cancer immunotherapies. Despite this, the developmental biology of exhausted CD8+ T cells (Tex) remains poorly defined, restraining improvement of strategies aimed at "re-invigorating" Tex cells. Here, we defined a four-cell-stage developmental framework for Tex cells. Two TCF1+ progenitor subsets were identified, one tissue restricted and quiescent and one more blood accessible, that gradually lost TCF1 as it divided and converted to a third intermediate Tex subset. This intermediate subset re-engaged some effector biology and increased upon PD-L1 blockade but ultimately converted into a fourth, terminally exhausted subset. By using transcriptional and epigenetic analyses, we identified the control mechanisms underlying subset transitions and defined a key interplay between TCF1, T-bet, and Tox in the process. These data reveal a four-stage developmental hierarchy for Tex cells and define the molecular, transcriptional, and epigenetic mechanisms that could provide opportunities to improve cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epigênese Genética/imunologia , Neoplasias/imunologia , Subpopulações de Linfócitos T/imunologia , Transcrição Genética/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Epigênese Genética/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/imunologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Humanos , Imunoterapia/métodos , Camundongos Endogâmicos C57BL , Neoplasias/genética , Neoplasias/terapia , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Subpopulações de Linfócitos T/metabolismo , Transcrição Genética/genética
8.
Sci Rep ; 10(1): 7376, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355214

RESUMO

Radiation therapy has been shown to enhance the efficacy of various T cell-targeted immunotherapies that improve antigen-specific T cell expansion, T regulatory cell depletion, or effector T cell function. Additionally, radiation therapy has been proposed as a means to recruit T cells to the treatment site and modulate cancer cells as effector T cell targets. The significance of these features remains unclear. We set out to determine, in checkpoint inhibitor resistant models, which components of radiation are primarily responsible for overcoming this resistance. In order to model the vaccination effect of radiation, we used a Listeria monocytogenes based vaccine to generate a large population of tumor antigen specific T cells but found that the presence of cells with cytotoxic capacity was unable to replicate the efficacy of radiation with combination checkpoint blockade. Instead, we demonstrated that a major role of radiation was to increase the susceptibility of surviving cancer cells to CD8+ T cell-mediated control through enhanced MHC-I expression. We observed a novel mechanism of genetic induction of MHC-I in cancer cells through upregulation of the MHC-I transactivator NLRC5. These data support the critical role of local modulation of tumors by radiation to improve tumor control with combination immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação Neoplásica da Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunidade Celular , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Proteínas de Membrana/imunologia , Proteínas de Neoplasias/imunologia , Neoplasias Experimentais/imunologia , Transcrição Genética/imunologia , Regulação para Cima/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Classe I/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Neoplasias Experimentais/terapia , Radioterapia
9.
J Gen Virol ; 101(6): 645-650, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32391749

RESUMO

Lumpy skin disease virus (LSDV), a Capripoxvirus, is of economic importance in the cattle industry and is controlled by vaccination. A comparison was made of the host response to the two LSDV vaccines Neethling and Herbivac LS, with reference to the well-studied Orthopoxvirus, modified vaccinia Ankara (MVA), in a mouse model. Because the vaccines differ at the superoxide dismutase homologue (SOD) gene locus, recombinant SOD knock-out and knock-in nLSDV vaccines were constructed and all four vaccines were tested for the induction and inhibition of apoptosis. The SOD homologue was associated both with induction of apoptosis as well as inhibition of camptothecin-induced apoptosis. Histological analysis of chorioallantoic membranes of fertilized hens' eggs infected with the four different vaccines indicated marked mesodermal proliferation associated with vaccines containing the full-length SOD homologue as well as increased immune cell infiltration. Our findings suggest that the SOD homologue may influence vaccine immunogenicity.


Assuntos
Apoptose/genética , Interações Hospedeiro-Patógeno/genética , Doença Nodular Cutânea/genética , Doença Nodular Cutânea/virologia , Vírus da Doença Nodular Cutânea/genética , Superóxido Dismutase/genética , Transcrição Genética/genética , Animais , Apoptose/imunologia , Bovinos , Galinhas/imunologia , Galinhas/virologia , Feminino , Doença Nodular Cutânea/imunologia , Vírus da Doença Nodular Cutânea/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Superóxido Dismutase/imunologia , Transcrição Genética/imunologia , Vacinação/métodos , Vacinas Atenuadas/imunologia , Vírus Vaccinia/genética , Vírus Vaccinia/imunologia , Vacinas Virais/imunologia
10.
J Virol ; 94(11)2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32213610

RESUMO

Ebola virus (EBOV) continues to pose a significant threat to human health, as evidenced by the 2013-2016 epidemic in West Africa and the ongoing outbreak in the Democratic Republic of the Congo. EBOV causes hemorrhagic fever, organ damage, and shock culminating in death, with case fatality rates as high as 90%. This high lethality combined with the paucity of licensed medical countermeasures makes EBOV a critical human pathogen. Although EBOV infection results in significant damage to the liver and the adrenal glands, little is known about the molecular signatures of injury in these organs. Moreover, while changes in peripheral blood cells are becoming increasingly understood, the host responses within organs and lymphoid tissues remain poorly characterized. To address this knowledge gap, we tracked longitudinal transcriptional changes in tissues collected from EBOV-Makona-infected cynomolgus macaques. Following infection, both liver and adrenal glands exhibited significant and early downregulation of genes involved in metabolism, coagulation, hormone synthesis, and angiogenesis; upregulated genes were associated with inflammation. Analysis of lymphoid tissues showed early upregulation of genes that play a role in innate immunity and inflammation and downregulation of genes associated with cell cycle and adaptive immunity. Moreover, transient activation of innate immune responses and downregulation of humoral immune responses in lymphoid tissues were confirmed with flow cytometry. Together, these data suggest that the liver, adrenal gland, and lymphatic organs are important sites of EBOV infection and that dysregulating the function of these vital organs contributes to the development of Ebola virus disease.IMPORTANCE Ebola virus (EBOV) remains a high-priority pathogen since it continues to cause outbreaks with high case fatality rates. Although it is well established that EBOV results in severe organ damage, our understanding of tissue injury in the liver, adrenal glands, and lymphoid tissues remains limited. We begin to address this knowledge gap by conducting longitudinal gene expression studies in these tissues, which were collected from EBOV-infected cynomolgus macaques. We report robust and early gene expression changes within these tissues, indicating they are primary sites of EBOV infection. Furthermore, genes involved in metabolism, coagulation, and adaptive immunity were downregulated, while inflammation-related genes were upregulated. These results indicate significant tissue damage consistent with the development of hemorrhagic fever and lymphopenia. Our study provides novel insight into EBOV-host interactions and elucidates how host responses within the liver, adrenal glands, and lymphoid tissues contribute to EBOV pathogenesis.


Assuntos
Glândulas Suprarrenais , Ebolavirus , Regulação Viral da Expressão Gênica/imunologia , Doença pelo Vírus Ebola , Fígado , Tecido Linfoide , Doenças dos Macacos , Transcrição Genética/imunologia , Glândulas Suprarrenais/imunologia , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/virologia , Animais , Ebolavirus/imunologia , Ebolavirus/metabolismo , Feminino , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/metabolismo , Doença pelo Vírus Ebola/patologia , Doença pelo Vírus Ebola/veterinária , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Tecido Linfoide/imunologia , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Tecido Linfoide/virologia , Macaca fascicularis , Masculino , Doenças dos Macacos/imunologia , Doenças dos Macacos/metabolismo , Doenças dos Macacos/patologia , Doenças dos Macacos/virologia
11.
Infect Immun ; 88(5)2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32122943

RESUMO

Mycoplasma gallisepticum is the primary etiological agent of chronic respiratory disease in chickens. Live attenuated vaccines are most commonly used in the field to control the disease, but current vaccines have some limitations. Vaxsafe MG (strain ts-304) is a new vaccine candidate that is efficacious at a lower dose than the current commercial vaccine strain ts-11, from which it is derived. In this study, the transcriptional profiles of the trachea of unvaccinated chickens and chickens vaccinated with strain ts-304 were compared 2 weeks after challenge with M. gallisepticum strain Ap3AS during the chronic stage of infection. After challenge, genes, gene ontologies, pathways, and protein classes involved in inflammation, cytokine production and signaling, and cell proliferation were upregulated, while those involved in formation and motor movement of cilia, formation of intercellular junctional complexes, and formation of the cytoskeleton were downregulated in the unvaccinated birds compared to the vaccinated birds, reflecting immune dysregulation and the pathological changes induced in the trachea by infection with M. gallisepticum Vaccination appears to protect the structural and functional integrity of the tracheal mucosa 2 weeks after infection with M. gallisepticum.


Assuntos
Galinhas/imunologia , Galinhas/microbiologia , Mycoplasma gallisepticum/imunologia , Traqueia/imunologia , Traqueia/microbiologia , Transcrição Genética/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/imunologia , Proliferação de Células/fisiologia , Membrana Mucosa/imunologia , Membrana Mucosa/microbiologia , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/microbiologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Regulação para Cima/imunologia , Vacinação/métodos , Vacinas Atenuadas/imunologia
12.
Immunology ; 160(1): 24-37, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32022254

RESUMO

The transcription factor Foxp3 controls the differentiation and function of regulatory T-cells (Treg). Studies in the past decades identified numerous Foxp3-interacting protein partners. However, it is still not clear how Foxp3 produces the Treg-type transcriptomic landscape through cooperating with its partners. Here I show the current understanding of how Foxp3 transcription factor complexes regulate the differentiation, maintenance and functional maturation of Treg. Importantly, T-cell receptor (TCR) signalling plays central roles in Treg differentiation and Foxp3-mediated gene regulation. Differentiating Treg will have recognized their cognate antigens and received TCR signals before initiating Foxp3 transcription, which is triggered by TCR-induced transcription factors including NFAT, AP-1 and NF-κB. Once expressed, Foxp3 seizes TCR signal-induced transcriptional and epigenetic mechanisms through interacting with AML1/Runx1 and NFAT. Thus, Foxp3 modifies gene expression dynamics of TCR-induced genes, which constitute cardinal mechanisms for Treg-mediated immune suppression. Next, I discuss the following key topics, proposing new mechanistic models for Foxp3-mediated gene regulation: (i) how Foxp3 transcription is induced and maintained by the Foxp3-inducing enhanceosome and the Foxp3 autoregulatory transcription factor complex; (ii) molecular mechanisms for effector Treg differentiation (i.e. Treg maturation); (iii) how Foxp3 activates or represses its target genes through recruiting coactivators and corepressors; (iv) the 'decision-making' Foxp3-containing transcription factor complex for Th17 and Treg differentiation; and (v) the roles of post-translational modification in Foxp3 regulation. Thus, this article provides cutting-edge understanding of molecular biology of Foxp3 and Treg, integrating findings by biochemical and genomic studies.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Modelos Biológicos , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Animais , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Epigênese Genética/imunologia , Humanos , Ativação Linfocitária , Camundongos , Processamento de Proteína Pós-Traducional/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Transcrição Genética/imunologia
14.
Immunology ; 160(1): 38-51, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32027025

RESUMO

First discovered on the natural killer (NK) cell, the cell surface inhibitory receptor sialic acid-binding immunoglobulin-like lectin-7 (Siglec-7) is known for regulating many important biological activities. However, the detail regulatory mechanism for Siglec-7 expression in NK cells currently remains unclear. In this study, we aimed to investigate how cell surface Siglec-7 expression is regulated and found that, in both NK cell lines and peripheral NK cells, transcription was the main regulatory step. Furthermore, when NK-92MI and peripheral NK cells were treated with DNA methyltransferase (DNMT) inhibitor, the CpG island, with 9 CpG sites, in 5' Siglec-7 promoter became noticeably hypomethylated, and Siglec-7 expression increased in both RNA transcript and surface protein. Within this CpG island, we identified both CpG 8 and CpG 9 as two key regulators responsible for Siglec-7 expression. Additionally, by using histone deacetylases (HDAC) inhibitor, butyric acid, we showed that Siglec-7 expression was also subjected to the histone modification. And a combined treatment with both 5-azacytidine and butyric acid showed an additive effect on Siglec-7 transcript expression in peripheral NK cells.


Assuntos
Antígenos de Diferenciação Mielomonocítica/genética , Epigênese Genética/imunologia , Células Matadoras Naturais/imunologia , Lectinas/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Azacitidina/farmacologia , Ácido Butírico/farmacologia , Linhagem Celular , Ilhas de CpG/genética , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/imunologia , Epigênese Genética/efeitos dos fármacos , Código das Histonas/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Lectinas/metabolismo , Regiões Promotoras Genéticas/genética , RNA-Seq , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/imunologia
15.
Sci Rep ; 10(1): 2227, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32042107

RESUMO

HIV-1 viral transcription persists in patients despite antiretroviral treatment, potentially due to intermittent HIV-1 LTR activation. While several mathematical models have been explored in the context of LTR-protein interactions, in this work for the first time HIV-1 LTR model featuring repressed, intermediate, and activated LTR states is integrated with generation of long (env) and short (TAR) RNAs and proteins (Tat, Pr55, and p24) in T-cells and macrophages using both cell lines and infected primary cells. This type of extended modeling framework allows us to compare and contrast behavior of these two cell types. We demonstrate that they exhibit unique LTR dynamics, which ultimately results in differences in the magnitude of viral products generated. One of the distinctive features of this work is that it relies on experimental data in reaction rate computations. Two RNA transcription rates from the activated promoter states are fit by comparison of experimental data to model predictions. Fitting to the data also provides estimates for the degradation/exit rates for long and short viral RNA. Our experimentally generated data is in reasonable agreement for the T-cell as well macrophage population and gives strong evidence in support of using the proposed integrated modeling paradigm. Sensitivity analysis performed using Latin hypercube sampling method confirms robustness of the model with respect to small parameter perturbations. Finally, incorporation of a transcription inhibitor (F07#13) into the governing equations demonstrates how the model can be used to assess drug efficacy. Collectively, our model indicates transcriptional differences between latently HIV-1 infected T-cells and macrophages and provides a novel platform to study various transcriptional dynamics leading to latency or activation in numerous cell types and physiological conditions.


Assuntos
Fármacos Anti-HIV/farmacologia , Regulação Viral da Expressão Gênica/imunologia , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Macrófagos/imunologia , Linfócitos T/imunologia , Fármacos Anti-HIV/uso terapêutico , Linhagem Celular , Farmacorresistência Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Farmacorresistência Viral/imunologia , Infecções por HIV/sangue , Infecções por HIV/imunologia , Repetição Terminal Longa de HIV/genética , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Humanos , Macrófagos/virologia , Modelos Genéticos , Modelos Imunológicos , Cultura Primária de Células , RNA Viral/genética , RNA Viral/metabolismo , Linfócitos T/virologia , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/imunologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética , Replicação Viral/imunologia
16.
PLoS Pathog ; 16(2): e1008151, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32109259

RESUMO

HIV latency is the major barrier to a cure for people living with HIV (PLWH) on antiretroviral therapy (ART) because the virus persists in long-lived non-proliferating and proliferating latently infected CD4+ T cells. Latently infected CD4+ T cells do not express viral proteins and are therefore not visible to immune mediated clearance. Therefore, identifying interventions that can reverse latency and also enhance immune mediated clearance is of high interest. Interferons (IFNs) have multiple immune enhancing effects and can inhibit HIV replication in activated CD4+ T cells. However, the effects of IFNs on the establishment and reversal of HIV latency is not understood. Using an in vitro model of latency, we demonstrated that plasmacytoid dendritic cells (pDC) inhibit the establishment of HIV latency through secretion of type I IFNα, IFNß and IFNω but not IFNε or type III IFNλ1 and IFNλ3. However, once latency was established, IFNα but no other IFNs were able to efficiently reverse latency in both an in vitro model of latency and CD4+ T cells collected from PLWH on suppressive ART. Binding of IFNα to its receptor expressed on primary CD4+ T cells did not induce activation of the canonical or non-canonical NFκB pathway but did induce phosphorylation of STAT1, 3 and 5 proteins. STAT5 has been previously demonstrated to bind to the HIV long terminal repeat and activate HIV transcription. We demonstrate diverse effects of interferons on HIV latency with type I IFNα; inhibiting the establishment of latency but also reversing HIV latency once latency is established.


Assuntos
Linfócitos T CD4-Positivos , Repetição Terminal Longa de HIV/imunologia , HIV-1/fisiologia , Interferon-alfa/imunologia , Transcrição Genética/imunologia , Latência Viral/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Células Dendríticas/virologia , Células HEK293 , Humanos , NF-kappa B/imunologia , Fatores de Transcrição STAT/imunologia
17.
J Immunol ; 204(7): 1760-1769, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32094206

RESUMO

Lymphocyte lineage specification and commitment requires the activation of lineage-specific genes and repression of alternative lineage genes, respectively. The mechanisms governing alternative lineage gene repression and commitment in lymphocytes are largely unknown. In this study, we demonstrate that Ezh2, which represses gene expression through methylation of histone 3 lysine 27, was essential for repression of numerous genes, including genes encoding innate lymphocyte transcription factors, specifically in murine B lymphocyte progenitors, but these cells maintained their B lymphocyte identity. However, adult Ezh2-deficient B lymphocytes expressed Lin28b, which encodes an RNA-binding protein associated with fetal hematopoietic gene expression programs, and these cells acquired a fetal B-1 lymphocyte phenotype in vitro and in vivo. Therefore, Ezh2 coordinates the repression of multiple gene programs in B lymphocytes and maintains the adult B-2 cell fate.


Assuntos
Linfócitos B/imunologia , Proteína Potenciadora do Homólogo 2 de Zeste/imunologia , Imunidade Inata/imunologia , Células Precursoras de Linfócitos B/imunologia , Transcrição Genética/imunologia , Animais , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Expressão Gênica/imunologia , Histonas/imunologia , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Ligação a RNA/imunologia , Fatores de Transcrição/imunologia
18.
Immunology ; 160(1): 78-89, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32107769

RESUMO

Annexins are well-known Ca2+ phospholipid-binding proteins, which have a wide variety of cellular functions. The role of annexin A1 (AnxA1) in the innate immune system has focused mainly on the anti-inflammatory and proresolving properties through its binding to the formyl-peptide receptor 2 (FPR2)/ALX receptor. However, studies suggesting an intracellular role of AnxA1 are emerging. In this study, we aimed to understand the role of AnxA1 for interleukin (IL)-1ß release in response to activators of the nucleotide-binding domain leucine-rich repeat (NLR) and pyrin domain containing receptor 3 (NLRP3) inflammasome. Using AnxA1 knockout mice, we observed that AnxA1 is required for IL-1ß release in vivo and in vitro. These effects were due to reduction of transcriptional levels of IL-1ß, NLRP3 and caspase-1, a step called NLRP3 priming. Moreover, we demonstrate that AnxA1 co-localize and directly bind to NLRP3, suggesting the role of AnxA1 in inflammasome activation is independent of its anti-inflammatory role via FPR2. Therefore, AnxA1 regulates NLRP3 inflammasome priming and activation in a FPR2-independent manner.


Assuntos
Anexina A1/metabolismo , Inflamassomos/imunologia , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Administração Intranasal , Animais , Cartilagem Articular , Caspase 1/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Gota/induzido quimicamente , Gota/imunologia , Gota/patologia , Humanos , Inflamassomos/metabolismo , Injeções Intra-Articulares , Pulmão/imunologia , Pulmão/patologia , Macrófagos , Masculino , Camundongos , Camundongos Knockout , Cultura Primária de Células , Ligação Proteica/imunologia , Dióxido de Silício/administração & dosagem , Dióxido de Silício/toxicidade , Silicose/imunologia , Silicose/patologia , Transcrição Genética/imunologia , Ácido Úrico/administração & dosagem , Ácido Úrico/toxicidade
19.
J Immunol ; 204(5): 1334-1344, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953354

RESUMO

The IL1A and IL1B genes lie in close proximity on chromosome 2 near the gene for their natural inhibitor, IL1RN Despite diverse functions, they are all three inducible through TLR4 signaling but with distinct kinetics. This study analyzed transcriptional induction kinetics, chromosome looping, and enhancer RNA production to understand the distinct regulation of these three genes in human cells. IL1A, IL1B, and IL1RN were rapidly induced after stimulation with LPS; however, IL1B mRNA production was less inhibitable by iBET151, suggesting it does not use pause-release regulation. Surprisingly, chromatin looping contacts between IL1A and IL1B were highly intermingled, although those of IL1RN were distinct, and we focused on comparing IL1A and IL1B transcriptional pathways. Our studies demonstrated that enhancer RNAs were produced from a subset of the regulatory regions, that they were critical for production of the mRNAs, and that they bound a diverse array of RNA binding proteins, including p300 but not CBP. We, furthermore, demonstrated that recruitment of p300 was dependent on MAPKs. Integrator is another RNA binding protein recruited to the promoters and enhancers, and its recruitment was more dependent on NF-κB than MAPKs. We found that integrator and NELF, an RNA polymerase II pausing protein, were associated with RNA in a manner that facilitated interaction. We conclude that IL1A and IL1B share many regulatory contacts, signaling pathways, and interactions with enhancer RNAs. A complex of protein interactions with enhancer RNAs emphasize the role of enhancer RNAs and the overall structural aspects of transcriptional regulation.


Assuntos
Proteína p300 Associada a E1A/imunologia , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Lipopolissacarídeos/farmacologia , Monócitos/imunologia , Proteínas de Ligação a RNA/imunologia , Transcrição Genética , Linhagem Celular , Proteína p300 Associada a E1A/genética , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1alfa/genética , Interleucina-1beta/genética , Proteínas de Ligação a RNA/genética , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/imunologia
20.
J Immunol ; 204(4): 923-932, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31900338

RESUMO

The transcription factor BHLHE40 is an emerging regulator of the immune system. Recent studies suggest that BHLHE40 regulates type 2 immunity, but this has not been demonstrated in vivo. We found that BHLHE40 is required in T cells for a protective TH2 cell response in mice infected with the helminth Heligmosomoides polygyrus bakeri H. polygyrus elicited changes in gene and cytokine expression by lamina propria CD4+ T cells, many of which were BHLHE40 dependent, including production of the common ß (CSF2RB) chain family cytokines GM-CSF and IL-5. In contrast to deficiency in GM-CSF or IL-5 alone, loss of both GM-CSF and IL-5 signaling impaired protection against H. polygyrus Overall, we show that BHLHE40 regulates the TH2 cell transcriptional program during helminth infection to support normal expression of Csf2, Il5, and other genes required for protection and reveal unexpected redundancy of common ß chain-dependent cytokines previously thought to possess substantially divergent functions.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Proteínas de Homeodomínio/metabolismo , Interleucina-5/metabolismo , Nematospiroides dubius/imunologia , Infecções por Strongylida/imunologia , Células Th2/imunologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Subunidade beta Comum dos Receptores de Citocinas/genética , Subunidade beta Comum dos Receptores de Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Proteínas de Homeodomínio/genética , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/genética , Interleucina-5/antagonistas & inibidores , Interleucina-5/genética , Interleucina-5/imunologia , Camundongos , Camundongos Knockout , Membrana Mucosa/citologia , Membrana Mucosa/imunologia , Membrana Mucosa/metabolismo , Infecções por Strongylida/parasitologia , Células Th2/efeitos dos fármacos , Transcrição Genética/imunologia
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