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1.
Nature ; 567(7749): 525-529, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30814730

RESUMO

T cells become dysfunctional when they encounter self antigens or are exposed to chronic infection or to the tumour microenvironment1. The function of T cells is tightly regulated by a combinational co-stimulatory signal, and dominance of negative co-stimulation results in T cell dysfunction2. However, the molecular mechanisms that underlie this dysfunction remain unclear. Here, using an in vitro T cell tolerance induction system in mice, we characterize genome-wide epigenetic and gene expression features in tolerant T cells, and show that they are distinct from effector and regulatory T cells. Notably, the transcription factor NR4A1 is stably expressed at high levels in tolerant T cells. Overexpression of NR4A1 inhibits effector T cell differentiation, whereas deletion of NR4A1 overcomes T cell tolerance and exaggerates effector function, as well as enhancing immunity against tumour and chronic virus. Mechanistically, NR4A1 is preferentially recruited to binding sites of the transcription factor AP-1, where it represses effector-gene expression by inhibiting AP-1 function. NR4A1 binding also promotes acetylation of histone 3 at lysine 27 (H3K27ac), leading to activation of tolerance-related genes. This study thus identifies NR4A1 as a key general regulator in the induction of T cell dysfunction, and a potential target for tumour immunotherapy.


Assuntos
Regulação da Expressão Gênica/genética , Genoma , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Linfócitos T/metabolismo , Linfócitos T/patologia , Acetilação , Animais , Infecções por Arenaviridae/imunologia , Infecções por Arenaviridae/virologia , Linhagem Celular Tumoral , Colite/imunologia , Colite/patologia , Colite/terapia , Epigênese Genética , Feminino , Histonas/química , Histonas/metabolismo , Tolerância Imunológica/genética , Imunoterapia , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Linfócitos T/imunologia , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica
2.
Lab Invest ; 97(10): 1180-1187, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28504686

RESUMO

Nordihydroguaiaretic acid (NDGA) and its synthetic chiral analog dl-nordihydroguaiaretic acid (Nordy) show collective benefits in anti-tumor, and defending against viral and bacterial infections. Here, we synthetized a new derivative-NDGA-P21 based on NDGA structure. Regardless of the structural similarity, NDGA-P21 exhibited stronger capability in suppression of glioblastoma (GBM) cell growth as compared to Nordy. Mechanically, NDGA-P21 is able to arrest cell cycle of GBM cells in G0/G1 phase, and to block cell proliferation sequentially. It is important to note that NDGA-P21 is able to impair the stemness of glioma stem-like cells (GSLCs) via measurement of colony formation and sphere formation. Taken together, the novel NDGA-based compound NDGA-P21 exhibits potential therty -20 apeutic implications through inhibiting proliferation of glioma cells and self-renewal capability of GSLCs.


Assuntos
Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioma/metabolismo , Masoprocol/análogos & derivados , Masoprocol/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos
3.
Mol Plant Pathol ; 25(3): e13443, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38502146

RESUMO

SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) facilitate docking and fusion of vesicles with their target membranes, playing a crucial role in vesicle trafficking and exocytosis. However, the spatial assembly and roles of plasma membrane (PM)-associated SNAREs in phytopathogen development and pathogenicity are not clearly understood. In this study, we analysed the roles and molecular mechanisms of PM-associated SNARE complexes in the banana Fusarium wilt fungus Fusarium oxysporum f. sp. cubense tropical race 4 (FocTR4). Our findings demonstrate that FocSso1 is important for the fungal growth, conidiation, host penetration and colonization. Mechanistically, FocSso1 regulates protein secretion by mediating vesicle docking and fusion with the PM and hyphal apex. Interestingly, a FocSso1-FocSec9-FocSnc1 complex was observed to assemble not only at the fungal PM but also on the growing hyphal apex, facilitating exocytosis. FocSso2, a paralogue of FocSso1, was also found to form a ternary SNARE complex with FocSec9 and FocSnc1, but it mainly localizes to the PM in old hyphae. The functional analysis of this protein demonstrated that it is dispensable for the fungal growth but necessary for host penetration and colonization. The other subunits, FocSec9 and FocSnc1, are involved in the fungal development and facilitate host penetration. Furthermore, FocSso1 and FocSnc1 are functionally interdependent, as loss of FocSso1 leads to mis-sorting and degradation of FocSnc1 in the vacuole and vice versa. Overall, this study provides insight into the formation of two spatially and functionally distinct PM SNARE complexes and their involvement in vesicle exocytosis to regulate development and pathogenicity of FocTR4.


Assuntos
Fusarium , Membrana Celular , Citoplasma , Proteínas SNARE
4.
Cancer Cell ; 41(4): 693-710.e8, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36963400

RESUMO

Malignant gliomas are largely refractory to immune checkpoint blockade (ICB) therapy. To explore the underlying immune regulators, we examine the microenvironment in glioma and find that tumor-infiltrating T cells are mainly confined to the perivascular cuffs and express high levels of CCR5, CXCR3, and programmed cell death protein 1 (PD-1). Combined analysis of T cell clustering with T cell receptor (TCR) clone expansion shows that potential tumor-killing T cells are mainly categorized into pre-exhausted/exhausted and effector CD8+ T subsets, as well as cytotoxic CD4+ T subsets. Notably, a distinct subpopulation of CD4+ T cells exhibits innate-like features with preferential interleukin-8 (IL-8) expression. With IL-8-humanized mouse strain, we demonstrate that IL-8-producing CD4+ T, myeloid, and tumor cells orchestrate myeloid-derived suppressor cell infiltration and angiogenesis, which results in enhanced tumor growth but reduced ICB efficacy. Antibody-mediated IL-8 blockade or the inhibition of its receptor, CXCR1/2, unleashes anti-PD-1-mediated antitumor immunity. Our findings thus highlight IL-8 as a combinational immunotherapy target for glioma.


Assuntos
Glioma , Inibidores de Checkpoint Imunológico , Interleucina-8 , Animais , Camundongos , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Glioma/tratamento farmacológico , Glioma/patologia , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia/métodos , Interleucina-8/metabolismo , Linfócitos T , Microambiente Tumoral
5.
Nanomaterials (Basel) ; 12(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35631003

RESUMO

Cathode materials have impeded the development of aqueous Zn batteries (AZBs) for a long time due to their low capacity and poor cycling stability. Here, a "two birds with one stone" strategy is devised to optimize the Ni-Co hydroxide cathode material (NCH) for AZBs, which plays an essential role in both composition adjustment and morphology majorization. The F-doped Ni-Co hydroxide (FNCH) exhibits a unique nanoarray structure consisting of the 2D flake-like unit, furnishing abundant active sites for the redox reaction. A series of analyses prove that FNCH delivers improved electrical conductivity and enhanced electrochemical activity. Contributing to the unique morphology and adjusted characteristics, FNCH presents a higher discharge-specific capacity, more advantageous rate capability and competitive cycling stability than NCH. As a result, an aqueous Zn battery assembled with a FNCH cathode and Zn anode exhibits a high capacity of 0.23 mAh cm-2 at 1 mA cm-2, and retains 0.10 mAh cm-2 at 10 mA cm-2. More importantly, the FNCH-Zn battery demonstrates no capacity decay after 3000 cycles with a conspicuous capacity of 0.15 mAh cm-2 at 8 mA cm-2, indicating a superior cycling performance. This work provides a facile approach to develop high-performance cathodes for aqueous Zn batteries.

6.
EBioMedicine ; 75: 103794, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34973625

RESUMO

BACKGROUND: B cell follicles are immune-privileged sites where intensive HIV-1 replication and latency occur, preventing a permanent cure. Recent study showed that CXCR5+ NK cells in B cell follicles can inhibit SIV replication in African green monkeys, but this has not been reported in HIV-1 infected patients. METHODS: Lymphocytes and tissue sections of lymph node were collected from 11 HIV-1 positive antiretroviral therapy (ART)-naive and 19 HIV-1 negative donors. We performed immunofluorescence and RNA-scope to detect the location of CXCR5+ NK cells and its relationship with HIV-1 RNA, and performed flow cytometry and RNA-seq to analyze the frequency, phenotypic and functional characteristics of CXCR5+ NK cells. The CXCL13 expression were detected by immunohistochemistry. FINDINGS: CXCR5+ NK cells, which accumulated in LNs from HIV-1 infected individuals, expressed high levels of activating receptors such as NKG2D and NKp44. CXCR5+ NK cells had upregulated expression of CD107a and ß-chemokines, which were partially impaired in HIV-1 infection. Importantly, the frequency of CXCR5+NK cells was inversely related to the HIV-1 viral burden in LNs. In addition, CXCL13-the ligand of CXCR5-was upregulated in HIV-1 infected individuals and positively correlated with the frequency of CXCR5+ NK cells. INTERPRETATION: During chronic HIV-1 infection, CXCR5+ NK cells accumulated in lymph node, exhibit altered immune characteristics and underlying anti-HIV-1 effect, which may be an effective target for a functional cure of HIV-1.


Assuntos
Infecções por HIV , HIV-1 , Animais , Chlorocebus aethiops , Humanos , Células Matadoras Naturais , Linfonodos/metabolismo , Receptores CXCR5/genética , Replicação Viral
7.
Gland Surg ; 10(1): 378-385, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33633995

RESUMO

Although ectopic thyroid can be found in thoracic locations, the discovery of abdominal ectopic thyroid is often an accidental event. Moreover, abdominal ectopic thyroid is easily misdiagnosed due to the rarity of these cases and the difficulties in the preoperative diagnosis process. Thus, we aimed to assess the prevalence and features of abdominal ectopic thyroid and to highlight the current knowledge about the clinical characteristics and management of this condition by analyzing a case report of abdominal ectopic thyroid and reviewing the literature. A 70-year-old woman with a 3-year history of gradually increasing abdominal distension in the right lower quadrant of the abdomen was admitted to the hospital. Contrast-enhanced computed tomography (CT) of the abdomen revealed a retroperitoneal mass. The patient underwent Da Vinci robotic surgery, and the retroperitoneal mass was completely resected. Subsequently, the pathologic diagnosis of the mass was ET. The patient had no discomfort or symptoms when she was discharged from the hospital and at the postoperative 1, 3, 6, 9 and 12 months follow-up. The summary of literature review suggested that abdominal ectopic thyroid is still rare although there are some reports. Nonetheless, the cause of abdominal ectopic thyroid is unclear, and abdominal ectopic thyroid has the following characteristics: more common in women than in men, asymptomatic in the majority of the cases, difficult to diagnose, and found by excluding metastasis. Most ectopic thyroid is treated with surgery, and minimally invasive techniques have been increasingly performed. This is the first report on Da Vinci robotic resection for large rare retroperitoneal ET, and this case highlights that ET should be considered when patients present with similar imaging findings in the abdomen.

8.
J Clin Invest ; 131(6)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720048

RESUMO

Chronic HIV-1 infection is generally characterized by progressive CD4+ T cell depletion due to direct and bystander death that is closely associated with persistent HIV-1 replication and an inflammatory environment in vivo. The mechanisms underlying the loss of CD4+ T cells in patients with chronic HIV-1 infection are incompletely understood. In this study, we simultaneously monitored caspase-1 and caspase-3 activation in circulating CD4+ T cells, which revealed that pyroptotic and apoptotic CD4+ T cells are distinct cell populations with different phenotypic characteristics. Levels of pyroptosis and apoptosis in CD4+ T cells were significantly elevated during chronic HIV-1 infection, and decreased following effective antiretroviral therapy. Notably, the occurrence of pyroptosis was further confirmed by elevated gasdermin D activation in lymph nodes of HIV-1-infected individuals. Mechanistically, caspase-1 activation closely correlated with the inflammatory marker expression and was shown to occur through NLRP3 inflammasome activation driven by virus-dependent and/or -independent ROS production, while caspase-3 activation in CD4+ T cells was more closely related to T cell activation status. Hence, our findings show that NLRP3-dependent pyroptosis plays an essential role in CD4+ T cell loss in HIV-1-infected patients and implicate pyroptosis signaling as a target for anti-HIV-1 treatment.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1 , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Adolescente , Adulto , Apoptose/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Estudos de Casos e Controles , Caspase 1/metabolismo , Caspase 3/metabolismo , Feminino , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Humanos , Inflamassomos/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Modelos Imunológicos , Piroptose/imunologia , Espécies Reativas de Oxigênio/metabolismo , Carga Viral , Adulto Jovem
9.
Science ; 369(6506): 984-988, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820125

RESUMO

Germinal center (GC) responses potentiate the generation of follicular regulatory T (TFR) cells. However, the molecular cues driving TFR cell formation remain unknown. Here, we show that sclerostin domain-containing protein 1 (SOSTDC1), secreted by a subpopulation of follicular helper T (TFH) cells and T-B cell border-enriched fibroblastic reticular cells, is developmentally required for TFR cell generation. Fate tracking and transcriptome assessment in reporter mice establishes SOSTDC1-expressing TFH cells as a distinct T cell population that develops after SOSTDC1- TFH cells and loses the ability to help B cells for antibody production. Notably, Sostdc1 ablation in TFH cells results in substantially reduced TFR cell numbers and consequently elevated GC responses. Mechanistically, SOSTDC1 blocks the WNT-ß-catenin axis and facilitates TFR cell differentiation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linfócitos B/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Centro Germinativo/imunologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Camundongos , Camundongos Mutantes , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
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