RESUMO
Regulatory T (Treg) cells are a barrier for tumor immunity and a target for immunotherapy. Using single-cell transcriptomics, we found that CD4+ T cells infiltrating primary and metastatic colorectal cancer and non-small-cell lung cancer are highly enriched for two subsets of comparable size and suppressor function comprising forkhead box protein P3+ Treg and eomesodermin homolog (EOMES)+ type 1 regulatory T (Tr1)-like cells also expressing granzyme K and chitinase-3-like protein 2. EOMES+ Tr1-like cells, but not Treg cells, were clonally related to effector T cells and were clonally expanded in primary and metastatic tumors, which is consistent with their proliferation and differentiation in situ. Using chitinase-3-like protein 2 as a subset signature, we found that the EOMES+ Tr1-like subset correlates with disease progression but is also associated with response to programmed cell death protein 1-targeted immunotherapy. Collectively, these findings highlight the heterogeneity of Treg cells that accumulate in primary tumors and metastases and identify a new prospective target for cancer immunotherapy.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Hematopoiese Clonal/imunologia , Neoplasias Colorretais/imunologia , Neoplasias Pulmonares/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma Pulmonar de Células não Pequenas/terapia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Proliferação de Células/genética , Quimioterapia Adjuvante/métodos , Quitinases/metabolismo , Colectomia , Colo/patologia , Colo/cirurgia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Conjuntos de Dados como Assunto , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/imunologia , Feminino , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica/imunologia , Granzimas/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Receptor de Morte Celular Programada 1/antagonistas & inibidores , RNA-Seq , Análise de Célula Única , Proteínas com Domínio T/metabolismo , Linfócitos T Reguladores/metabolismoRESUMO
Long noncoding RNAs are emerging as important regulators of cellular functions, but little is known of their role in the human immune system. Here we investigated long intergenic noncoding RNAs (lincRNAs) in 13 subsets of T lymphocytes and B lymphocytes by next-generation sequencing-based RNA sequencing (RNA-seq analysis) and de novo transcriptome reconstruction. We identified over 500 previously unknown lincRNAs and described lincRNA signatures. Expression of linc-MAF-4, a chromatin-associated lincRNA specific to the TH1 subset of helper T cells, was inversely correlated with expression of MAF, a TH2-associated transcription factor. Downregulation of linc-MAF-4 skewed T cell differentiation toward the TH2 phenotype. We identified a long-distance interaction between the genomic regions of the gene encoding linc-MAF-4 and MAF, where linc-MAF-4 associated with the chromatin modifiers LSD1 and EZH2; this suggested that linc-MAF-4 regulated MAF transcription through the recruitment of chromatin modifiers. Our results demonstrate a key role for lincRNA in T lymphocyte differentiation.
Assuntos
Fatores de Transcrição Maf/genética , RNA Longo não Codificante/genética , Linfócitos T/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Humanos , Fatores de Transcrição Maf/imunologia , RNA Longo não Codificante/imunologia , Transcrição Gênica/genética , Transcrição Gênica/imunologia , Transcriptoma/genética , Transcriptoma/imunologiaRESUMO
Tumor-infiltrating regulatory T lymphocytes (Treg) can suppress effector T cells specific for tumor antigens. Deeper molecular definitions of tumor-infiltrating-lymphocytes could thus offer therapeutic opportunities. Transcriptomes of T helper 1 (Th1), Th17, and Treg cells infiltrating colorectal or non-small-cell lung cancers were compared to transcriptomes of the same subsets from normal tissues and validated at the single-cell level. We found that tumor-infiltrating Treg cells were highly suppressive, upregulated several immune-checkpoints, and expressed on the cell surfaces specific signature molecules such as interleukin-1 receptor 2 (IL1R2), programmed death (PD)-1 Ligand1, PD-1 Ligand2, and CCR8 chemokine, which were not previously described on Treg cells. Remarkably, high expression in whole-tumor samples of Treg cell signature genes, such as LAYN, MAGEH1, or CCR8, correlated with poor prognosis. Our findings provide insights into the molecular identity and functions of human tumor-infiltrating Treg cells and define potential targets for tumor immunotherapy.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Neoplasias Colorretais/imunologia , Neoplasias Pulmonares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos T Reguladores/imunologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Separação Celular , Neoplasias Colorretais/mortalidade , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , TranscriptomaRESUMO
NF1 microdeletion syndrome, accounting for 5-11% of NF1 patients, is caused by a deletion in the NF1 region and it is generally characterized by a severe phenotype. Although 70% of NF1 microdeletion patients presents the same 1.4 Mb type-I deletion, some patients may show additional clinical features. Therefore, the contribution of several pathogenic mechanisms, besides haploinsufficiency of some genes within the deletion interval, is expected and needs to be defined. We investigated an altered expression of deletion flanking genes by qPCR in patients with type-1 NF1 deletion, compared to healthy donors, possibly contributing to the clinical traits of NF1 microdeletion syndrome. In addition, the 1.4-Mb deletion leads to changes in the 3D chromatin structure in the 17q11.2 region. Specifically, this deletion alters DNA-DNA interactions in the regions flanking the breakpoints, as demonstrated by our 4C-seq analysis. This alteration likely causes position effect on the expression of deletion flanking genes.Interestingly, 4C-seq analysis revealed that in microdeletion patients, an interaction was established between the RHOT1 promoter and the SLC6A4 gene, which showed increased expression. We performed NGS on putative modifier genes, and identified two "likely pathogenic" rare variants in RAS pathway, possibly contributing to incidental phenotypic features.This study provides new insights into understanding the pathogenesis of NF1 microdeletion syndrome and suggests a novel pathomechanism that contributes to the expression phenotype in addition to haploinsufficiency of genes located within the deletion.This is a pivotal approach that can be applied to unravel microdeletion syndromes, improving precision medicine, prognosis and patients' follow-up.
Assuntos
Deleção Cromossômica , Epigênese Genética , Haploinsuficiência , Neurofibromatose 1 , Humanos , Neurofibromatose 1/genética , Feminino , Masculino , Neurofibromina 1/genética , Cromossomos Humanos Par 17/genética , Fenótipo , Criança , Regiões Promotoras GenéticasRESUMO
Recent branching (100 MYA) of the mammalian evolutionary tree has enhanced brain complexity and functions at the putative cost of increased emotional circuitry vulnerability. Thus, to better understand psychopathology, a burden for the modern society, novel approaches should exploit evolutionary aspects of psychiatric-relevant molecular pathways. A handful of genes is nowadays tightly associated to psychiatric disorders. Among them, neuronal-enriched RbFOX1 modifies the activity of synaptic regulators in response to neuronal activity, keeping excitability within healthy domains. We here dissect a higher primates-restricted interaction between RbFOX1 and the transcriptional corepressor Lysine Specific Demethylase 1 (LSD1/KDM1A). A single nucleotide variation (AA to AG) in LSD1 gene appeared in higher primates and humans, endowing RbFOX1 with the ability to promote the alternative usage of a novel 3' AG splice site, which extends LSD1 exon E9 in the upstream intron (E9-long). Exon E9-long regulates LSD1 levels by Nonsense-Mediated mRNA Decay. As reintroduction of the archaic LSD1 variant (AA) abolishes E9-long splicing, the novel 3' AG splice site is necessary for RbFOX1 to control LSD1 levels. LSD1 is a homeostatic immediate early genes (IEGs) regulator playing a relevant part in environmental stress-response. In primates and humans, inclusion of LSD1 as RbFOX1 target provides RbFOX1 with the additional ability to regulate the IEGs. These data, together with extensive RbFOX1 involvement in psychiatric disorders and its stress-dependent regulation in male mice, suggest the RbFOX1-LSD1-IEGs axis as an evolutionary recent psychiatric-relevant pathway. Notably, outside the nervous system, RbFOX2-dependent LSD1 modulation could be a candidate deregulated mechanism in cancer.SIGNIFICANCE STATEMENT To be better understood, anxiety and depression need large human genetics studies aimed at further resolving the often ambiguous, aberrant neuronal pathomechanisms that impact corticolimbic circuitry physiology. Several genetic associations of the alternative splicing regulator RbFOX1 with psychiatric conditions suggest homeostatic unbalance as a neuronal signature of psychopathology. Here we move a step forward, characterizing a disease-relevant higher primates-specific pathway by which RbFOX1 acquires the ability to regulate neuronal levels of Lysine Specific Demethylase 1, an epigenetic modulator of environmental stress response. Thus, two brain-enriched enzymes, independently shown to homeostatically protect neurons with a clear readout in terms of emotional behavior in lower mammals, establish in higher primates and humans a new functional cooperation enhancing the complexity of environmental adaptation and stress vulnerability.
Assuntos
Processamento Alternativo , Lisina , Processamento Alternativo/genética , Animais , Encéfalo/metabolismo , Histona Desmetilases/genética , Humanos , Lisina/metabolismo , Masculino , Mamíferos , Camundongos , Primatas , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Proteínas Repressoras/genéticaRESUMO
Growing evidence suggests that conventional dendritic cells (cDCs) undergo aberrant maturation in COVID-19, which negatively affects T-cell activation. The presence of effector T cells in patients with mild disease and dysfunctional T cells in severely ill patients suggests that adequate T-cell responses limit disease severity. Understanding how cDCs cope with SARS-CoV-2 can help elucidate how protective immune responses are generated. Here, we report that cDC2 subtypes exhibit similar infection-induced gene signatures, with the upregulation of IFN-stimulated genes and IL-6 signaling pathways. Furthermore, comparison of cDCs between patients with severe and mild disease showed severely ill patients to exhibit profound downregulation of genes encoding molecules involved in antigen presentation, such as MHCII, TAP, and costimulatory proteins, whereas we observed the opposite for proinflammatory molecules, such as complement and coagulation factors. Thus, as disease severity increases, cDC2s exhibit enhanced inflammatory properties and lose antigen presentation capacity. Moreover, DC3s showed upregulation of anti-apoptotic genes and accumulated during infection. Direct exposure of cDC2s to the virus in vitro recapitulated the activation profile observed in vivo. Our findings suggest that SARS-CoV-2 interacts directly with cDC2s and implements an efficient immune escape mechanism that correlates with disease severity by downregulating crucial molecules required for T-cell activation.
Assuntos
COVID-19/imunologia , Células Dendríticas/imunologia , Ativação Linfocitária , SARS-CoV-2/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , HumanosRESUMO
The genome is no longer deemed as a fixed and inert item but rather as a moldable matter that is continuously evolving and adapting. Within this frame, Transposable Elements (TEs), ubiquitous, mobile, repetitive elements, are considered an alive portion of the genomes to date, whose functions, although long considered "dark", are now coming to light. Here we will review that, besides the detrimental effects that TE mobilization can induce, TEs have shaped genomes in their current form, promoting genome sizing, genomic rearrangements and shuffling of DNA sequences. Although TEs are mostly represented in the genomes by evolutionarily old, short, degenerated, and sedentary fossils, they have been thoroughly co-opted by the hosts as a prolific and original source of regulatory instruments for the control of gene transcription and genome organization in the nuclear space. For these reasons, the deregulation of TE expression and/or activity is implicated in the onset and progression of several diseases. It is likely that we have just revealed the outermost layers of TE functions. Further studies on this portion of the genome are required to unlock novel regulatory functions that could also be exploited for diagnostic and therapeutic approaches.
Assuntos
Elementos de DNA Transponíveis , Regulação da Expressão Gênica , Elementos de DNA Transponíveis/genética , Tamanho do Genoma , Fases de Leitura , Evolução MolecularRESUMO
Ex vivo gene expression and miRNA profiling of Eomes+ Tr1-like cells suggested that they represent a differentiation stage that is intermediate between Th1-cells and cytotoxic CD4+ T-cells. Several microRNAs were downregulated in Eomes+ Tr1-like cells that might inhibit Tr1-cell differentiation. In particular, miR-92a targeted Eomes, while miR-125a inhibited IFN-g and IL-10R expression.
Assuntos
Perfilação da Expressão Gênica , MicroRNAs/imunologia , Receptores de Interleucina-10/imunologia , Proteínas com Domínio T/imunologia , Células Th1/imunologia , HumanosRESUMO
The tumor microenvironment restrains conventional T cell (Tconv) activation while facilitating the expansion of Tregs. Here we showed that Tregs' advantage in the tumor milieu relies on supplemental energetic routes involving lipid metabolism. In murine models, tumor-infiltrating Tregs displayed intracellular lipid accumulation, which was attributable to an increased rate of fatty acid (FA) synthesis. Since the relative advantage in glucose uptake may fuel FA synthesis in intratumoral Tregs, we demonstrated that both glycolytic and oxidative metabolism contribute to Tregs' expansion. We corroborated our data in human tumors showing that Tregs displayed a gene signature oriented toward glycolysis and lipid synthesis. Our data support a model in which signals from the tumor microenvironment induce a circuitry of glycolysis, FA synthesis, and oxidation that confers a preferential proliferative advantage to Tregs, whose targeting might represent a strategy for cancer treatment.
Assuntos
Ácidos Graxos/imunologia , Glicólise/imunologia , Neoplasias Experimentais/imunologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/imunologia , Ácidos Graxos/genética , Humanos , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Oxirredução , Linfócitos T Reguladores/patologia , Microambiente Tumoral/genéticaRESUMO
Whether human IL-10-producing regulatory T cells ("Tr1") represent a distinct differentiation lineage or an unstable activation stage remains a key unsolved issue. Here, we report that Eomesodermin (Eomes) acted as a lineage-defining transcription factor in human IFN-γ/IL-10 coproducing Tr1-like cells. In vivo occurring Tr1-like cells expressed Eomes, and were clearly distinct from all other CD4+ T-cell subsets, including conventional cytotoxic CD4+ T cells. They expressed Granzyme (Gzm) K, but had lost CD40L and IL-7R expression. Eomes antagonized the Th17 fate, and directly controlled IFN-γ and GzmK expression. However, Eomes binding to the IL-10 promoter was not detectable in human CD4+ T cells, presumably because critical Tbox binding sites of the mouse were not conserved. A precommitment to a Tr1-like fate, i.e. concominant induction of Eomes, GzmK, and IFN-γ, was promoted by IL-4 and IL-12-secreting myeloid dendritic cells. Consistently, Th1 effector memory cells contained precommitted Eomes+ GzmK+ T cells. Stimulation with T-cell receptor (TCR) agonists and IL-27 promoted the generation of Tr1-like effector cells by inducing switching from CD40L to IL-10. Importantly, CD4+ Eomes+ T-cell subsets were present in lymphoid and nonlymphoid tissues, and their frequencies varied systemically in patients with inflammatory bowel disease and graft-versus-host disease. We propose that Eomes+ Tr1-like cells are effector cells of a unique GzmK-expressing CD4+ T-cell subset.
Assuntos
Doença Enxerto-Hospedeiro/imunologia , Doenças Inflamatórias Intestinais/imunologia , Proteínas com Domínio T/metabolismo , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Animais , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Regulação da Expressão Gênica , Granzimas/metabolismo , Humanos , Memória Imunológica , Interferon gama/metabolismo , Interleucina-10/metabolismo , Camundongos , Proteínas com Domínio T/genéticaRESUMO
: Transposable elements (TEs), which cover ~45% of the human genome, although firstly considered as "selfish" DNA, are nowadays recognized as driving forces in eukaryotic genome evolution. This capability resides in generating a plethora of sophisticated RNA regulatory networks that influence the cell type specific transcriptome in health and disease. Indeed, TEs are transcribed and their RNAs mediate multi-layered transcriptional regulatory functions in cellular identity establishment, but also in the regulation of cellular plasticity and adaptability to environmental cues, as occurs in the immune response. Moreover, TEs transcriptional deregulation also evolved to promote pathogenesis, as in autoimmune and inflammatory diseases and cancers. Importantly, many of these findings have been achieved through the employment of Next Generation Sequencing (NGS) technologies and bioinformatic tools that are in continuous improvement to overcome the limitations of analyzing TEs sequences. However, they are highly homologous, and their annotation is still ambiguous. Here, we will review some of the most recent findings, questions and improvements to study at high resolution this intriguing portion of the human genome in health and diseases, opening the scenario to novel therapeutic opportunities.
Assuntos
Elementos de DNA Transponíveis/genética , Genoma Humano/genética , Evolução Molecular , Sequenciamento de Nucleotídeos em Larga Escala , HumanosRESUMO
Dyslipidemia and altered iron metabolism are typical features of nonalcoholic fatty liver disease (NAFLD). Proprotein convertase subtilisin/kexin type 7 (PCSK7) gene variation has been associated with circulating lipids and liver damage during iron overload. The aim of this study was to examine the impact of the PCSK7 rs236918 variant on NAFLD-related traits in 1,801 individuals from the Liver Biopsy Cohort (LBC), 500,000 from the UK Biobank Cohort (UKBBC), and 4,580 from the Dallas Heart Study (DHS). The minor PCSK7 rs236918 C allele was associated with higher triglycerides, aminotransferases, and hepatic inflammation in the LBC (P < 0.05) and with hypercholesterolemia and liver disease in the UKBBC. In the DHS, PCSK7 missense variants were associated with circulating lipids. PCSK7 was expressed in hepatocytes and its hepatic expression correlated with that of lipogenic genes (P < 0.05). The rs236918 C allele was associated with upregulation of a new "intra-PCSK7" long noncoding RNA predicted to interact with the protein, higher hepatic and circulating PCSK7 protein (P < 0.01), which correlated with triglycerides (P = 0.04). In HepG2 cells, PCSK7 deletion reduced lipogenesis, fat accumulation, inflammation, transforming growth factor ß pathway activation, and fibrogenesis. In conclusion, PCSK7 gene variation is associated with dyslipidemia and more severe liver disease in high risk individuals, likely by modulating PCSK7 expression/activity.
Assuntos
Dislipidemias/metabolismo , Doenças Metabólicas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Subtilisinas/metabolismo , Adulto , Animais , Estudos Transversais , Dislipidemias/genética , Feminino , Genótipo , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Desequilíbrio de Ligação/genética , Desequilíbrio de Ligação/fisiologia , Lipogênese/genética , Lipogênese/fisiologia , Masculino , Doenças Metabólicas/genética , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/genética , Subtilisinas/genéticaRESUMO
BACKGROUND: IL-10 is an anti-inflammatory cytokine required for intestinal immune homeostasis. It mediates suppression of T-cell responses by type 1 regulatory T (TR1) cells but is also produced by CD25+ regulatory T (Treg) cells. OBJECTIVE: We aimed to identify and characterize human intestinal TR1 cells and to investigate whether they are a relevant cellular source of IL-10 in patients with inflammatory bowel diseases (IBDs). METHODS: CD4+ T cells isolated from the intestinal lamina propria of human subjects and mice were analyzed for phenotype, cytokine production, and suppressive capacities. Intracellular IL-10 expression by CD4+ T-cell subsets in the inflamed guts of patients with IBD (Crohn disease or ulcerative colitis) was compared with that in cells from noninflamed control subjects. Finally, the effects of proinflammatory cytokines on T-cell IL-10 expression were analyzed, and IL-1ß and IL-23 responsiveness was assessed. RESULTS: Intestinal TR1 cells could be identified by coexpression of CCR5 and programmed cell death protein 1 (PD-1) in human subjects and mice. CCR5+PD-1+ TR1 cells expressed IFN-γ and efficiently suppressed T-cell proliferation and transfer colitis. Intestinal IFN-γ+ TR1 cells, but not IL-7 receptor-positive TH cells or CD25+ Treg cells, showed lower IL-10 expression in patients with IBDs. TR1 cells were responsive to IL-23, and IFN-γ+ TR1 cells downregulated IL-10 with IL-1ß and IL-23. Conversely, CD25+ Treg cells expressed higher levels of IL-1 receptor but showed stable IL-10 expression. CONCLUSIONS: We provide the first ex vivo characterization of human intestinal TR1 cells. Selective downregulation of IL-10 by IFN-γ+ TR1 cells in response to proinflammatory cytokines is likely to drive excessive intestinal inflammation in patients with IBDs.
Assuntos
Citocinas/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Receptor de Morte Celular Programada 1/imunologia , Receptores CCR5/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Animais , Células Cultivadas , Neoplasias do Colo/imunologia , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) that is caused by autoreactive T cells and associated with viral infections. However, the phenotype of pathogenic T cells in peripheral blood remains to be defined, and how viruses promote MS is debated. OBJECTIVE: We aimed to identify and characterize potentially pathogenic autoreactive T cells, as well as protective antiviral T cells, in patients with MS. METHODS: We analyzed CD4+ helper T-cell subsets from peripheral blood or cerebrospinal fluid for cytokine production, gene expression, plasticity, homing potentials, and their reactivity to self-antigens and viral antigens in healthy subjects and patients with MS. Moreover, we monitored their frequencies in untreated and fingolimod- or natalizumab-treated patients with MS. RESULTS: TH1/TH17 central memory (TH1/TH17CM) cells were selectively increased in peripheral blood of patients with relapsing-remitting MS with a high disease score. TH1/TH17CM cells were closely related to conventional TH17 cells but had more pathogenic features. In particular, they could shuttle between lymph nodes and the CNS and produced encephalitogenic cytokines. The cerebrospinal fluid of patients with active MS was enriched for CXCL10 and contained mainly CXCR3-expressing TH1 and TH1/TH17 subsets. However, while TH1 cells responded consistently to viruses, TH1/TH17CM cells reacted strongly with John Cunningham virus in healthy subjects but responded instead to myelin-derived self-antigens in patients with MS. Fingolimod and natalizumab therapies efficiently targeted autoreactive TH1/TH17CM cells but also blocked virus-specific TH1 cells. CONCLUSIONS: We propose that autoreactive TH1/TH17CM cells expand in patients with MS and promote relapses after bystander recruitment to the CNS, whereas TH1 cells perform immune surveillance. Thus the selective targeting of TH1/TH17 cells could inhibit relapses without causing John Cunningham virus-dependent progressive multifocal encephalomyelitis.
Assuntos
Antígenos Virais/imunologia , Autoantígenos/imunologia , Vírus JC/imunologia , Esclerose Múltipla/imunologia , Células Th1/imunologia , Células Th17/imunologia , Adulto , Citocinas/líquido cefalorraquidiano , Citocinas/imunologia , Feminino , Cloridrato de Fingolimode/uso terapêutico , Expressão Gênica , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/genética , Natalizumab/uso terapêuticoRESUMO
The miRBase is the official miRNA repository which keeps the annotation updated on newly discovered miRNAs: it is also used as a reference for the design of miRNA profiling platforms. Nomenclature ambiguities generated by loosely updated platforms and design errors lead to incompatibilities among platforms, even from the same vendor. Published miRNA lists are thus generated with different profiling platforms that refer to diverse and not updated annotations. This greatly compromises searches, comparisons and analyses that rely on miRNA names only without taking into account the mature sequences, which is particularly critic when such analyses are carried over automatically. In this paper we introduce miRiadne, a web tool to harmonize miRNA nomenclature, which takes into account the original miRBase versions from 10 up to 21, and annotations of 40 common profiling platforms from nine brands that we manually curated. miRiadne uses the miRNA mature sequence to link miRBase versions and/or platforms to prevent nomenclature ambiguities. miRiadne was designed to simplify and support biologists and bioinformaticians in re-annotating their own miRNA lists and/or data sets. As Ariadne helped Theseus in escaping the mythological maze, miRiadne will help the miRNA researcher in escaping the nomenclature maze. miRiadne is freely accessible from the URL http://www.miriadne.org.
Assuntos
MicroRNAs/química , Anotação de Sequência Molecular , Software , Terminologia como Assunto , Internet , MicroRNAs/metabolismoRESUMO
Huntington's disease (HD) causes selective degeneration of striatal and cortical neurons, resulting in cell mosaicism of coexisting still functional and dysfunctional cells. The impact of non-cell autonomous mechanisms between these cellular states is poorly understood. Here we generated telencephalic organoids with healthy or HD cells, grown separately or as mosaics of the two genotypes. Single-cell RNA sequencing revealed neurodevelopmental abnormalities in the ventral fate acquisition of HD organoids, confirmed by cytoarchitectural and transcriptional defects leading to fewer GABAergic neurons, while dorsal populations showed milder phenotypes mainly in maturation trajectory. Healthy cells in mosaic organoids restored HD cell identity, trajectories, synaptic density, and communication pathways upon cell-cell contact, while showing no significant alterations when grown with HD cells. These findings highlight cell-type-specific alterations in HD and beneficial non-cell autonomous effects of healthy cells, emphasizing the therapeutic potential of modulating cell-cell communication in disease progression and treatment.
Assuntos
Doença de Huntington , Organoides , Fenótipo , Telencéfalo , Doença de Huntington/patologia , Doença de Huntington/genética , Doença de Huntington/metabolismo , Organoides/patologia , Organoides/metabolismo , Animais , Telencéfalo/patologia , Telencéfalo/citologia , Telencéfalo/metabolismo , Humanos , Camundongos , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/patologia , Análise de Célula Única , Comunicação Celular , Mosaicismo , Neurônios/metabolismo , Neurônios/patologiaRESUMO
IFNγ-producing ex-Th17 cells ['Th1/17'] were shown to play a key pathogenic role in experimental colitis and are abundant in the intestine. Here, we identified and characterised a novel, potentially colitogenic subset of Th17 cells in the intestine of patients with Crohn's disease [CD]. Human Th17 cells expressing CCR5 ['pTh17'] co-expressed T-bet and RORC/γt and produced very high levels of IL-17, together with IFN-γ. They had a gene signature of Th17 effector cells and were distinct from established Th1/17 cells. pTh17 cells, but not Th1/17 cells, were associated with intestinal inflammation in CD, and decreased upon successful anti-TNF therapy with infliximab. Conventional CCR5[-]Th17 cells differentiated to pTh17 cells with IL-23 in vitro. Moreover, anti-IL-23 therapy with risankizumab strongly reduced pTh17 cells in the intestine. Importantly, intestinal pTh17 cells were selectively activated by adherent-invasive Escherichia coli [AIEC], but not by a commensal/probiotic E. coli strain. AIEC induced high levels of IL-23 and RANTES from dendritic cells [DC]. Intestinal CCR5+Th1/17 cells responded instead to cytomegalovirus and were reduced in ulcerative colitis [UC], suggesting an unexpected protective role. In conclusion, we identified an IL-23-inducible subset of human intestinal Th17 cells. pTh17 cells produced high levels of pro-inflammatory cytokines, were selectively associated with intestinal inflammation in CD, and responded to CD-associated AIEC, suggesting a key colitogenic role.
Assuntos
Doença de Crohn , Infecções por Escherichia coli , Humanos , Doença de Crohn/patologia , Escherichia coli , Células Th17/patologia , Inibidores do Fator de Necrose Tumoral , Intestinos/patologia , Inflamação/patologia , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/patologia , Interleucina-23 , Mucosa Intestinal/patologia , Aderência BacterianaRESUMO
Lipid and cholesterol metabolism play a crucial role in tumor cell behavior and in shaping the tumor microenvironment. In particular, enzymatic and non-enzymatic cholesterol metabolism, and derived metabolites control dendritic cell (DC) functions, ultimately impacting tumor antigen presentation within and outside the tumor mass, dampening tumor immunity and immunotherapeutic attempts. The mechanisms accounting for such events remain largely to be defined. Here we perturbed (oxy)sterol metabolism genetically and pharmacologically and analyzed the tumor lipidome landscape in relation to the tumor-infiltrating immune cells. We report that perturbing the lipidome of tumor microenvironment by the expression of sulfotransferase 2B1b crucial in cholesterol and oxysterol sulfate synthesis, favored intratumoral representation of monocyte-derived antigen-presenting cells, including monocyte-DCs. We also found that treating mice with a newly developed antagonist of the oxysterol receptors Liver X Receptors (LXRs), promoted intratumoral monocyte-DC differentiation, delayed tumor growth and synergized with anti-PD-1 immunotherapy and adoptive T cell therapy. Of note, looking at LXR/cholesterol gene signature in melanoma patients treated with anti-PD-1-based immunotherapy predicted diverse clinical outcomes. Indeed, patients whose tumors were poorly infiltrated by monocytes/macrophages expressing LXR target genes showed improved survival over the course of therapy. Thus, our data support a role for (oxy)sterol metabolism in shaping monocyte-to-DC differentiation, and in tumor antigen presentation critical for responsiveness to immunotherapy. The identification of a new LXR antagonist opens new treatment avenues for cancer patients.
Assuntos
Melanoma , Monócitos , Camundongos , Animais , Monócitos/metabolismo , Diferenciação Celular , Colesterol/metabolismo , Apresentação de Antígeno , Células Dendríticas/metabolismo , Microambiente TumoralRESUMO
E2 ubiquitin-conjugating enzymes are crucial mediators of protein ubiquitination, which strongly influence the ultimate fate of the target substrates. Recently, it has been shown that the activity of several enzymes of the ubiquitination pathway is finely tuned by phosphorylation, an ubiquitous mechanism for cellular regulation, which modulates protein conformation. In this contribution, we provide the first rationale, at the molecular level, of the regulatory mechanism mediated by casein kinase 2 (CK2) phosphorylation of E2 Cdc34-like enzymes. In particular, we identify two co-evolving signature elements in one of the larger families of E2 enzymes: an acidic insertion in ß4α2 loop in the proximity of the catalytic cysteine and two conserved key serine residues within the catalytic domain, which are phosphorylated by CK2. Our investigations, using yeast Cdc34 as a model, through 2.5 µs molecular dynamics simulations and biochemical assays, define these two elements as an important phosphorylation-controlled switch that modulates opening and closing of the catalytic cleft. The mechanism relies on electrostatic repulsions between a conserved serine phosphorylated by CK2 and the acidic residues of the ß4α2 loop, promoting E2 ubiquitin charging activity. Our investigation identifies a new and unexpected pivotal role for the acidic loop, providing the first evidence that this loop is crucial not only for downstream events related to ubiquitin chain assembly, but is also mandatory for the modulation of an upstream crucial step of the ubiquitin pathway: the ubiquitin charging in the E2 catalytic cleft.
Assuntos
Proteínas de Saccharomyces cerevisiae/química , Enzimas de Conjugação de Ubiquitina/química , Complexos Ubiquitina-Proteína Ligase/química , Ubiquitina/química , Sequência de Aminoácidos , Ciclossomo-Complexo Promotor de Anáfase , Humanos , Simulação de Dinâmica Molecular , Anotação de Sequência Molecular , Dados de Sequência Molecular , Fosforilação , Análise de Componente Principal , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Termodinâmica , Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismoRESUMO
How gene expression is controlled to preserve human T cell quiescence is poorly understood. Here we show that non-canonical splicing variants containing long interspersed nuclear element 1 (LINE1) enforce naive CD4+ T cell quiescence. LINE1-containing transcripts are derived from CD4+ T cell-specific genes upregulated during T cell activation. In naive CD4+ T cells, LINE1-containing transcripts are regulated by the transcription factor IRF4 and kept at chromatin by nucleolin; these transcripts act in cis, hampering levels of histone 3 (H3) lysine 36 trimethyl (H3K36me3) and stalling gene expression. T cell activation induces LINE1-containing transcript downregulation by the splicing suppressor PTBP1 and promotes expression of the corresponding protein-coding genes by the elongating factor GTF2F1 through mTORC1. Dysfunctional T cells, exhausted in vitro or tumor-infiltrating lymphocytes (TILs), accumulate LINE1-containing transcripts at chromatin. Remarkably, depletion of LINE1-containing transcripts restores TIL effector function. Our study identifies a role for LINE1 elements in maintaining T cell quiescence and suggests that an abundance of LINE1-containing transcripts is critical for T cell effector function and exhaustion.