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1.
J Am Coll Health ; 71(4): 1036-1044, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34252352

RESUMO

OBJECTIVE: To investigate whether pre-season self-reported mental toughness and self-regulation strategies predicts post-season stress, mental health, group cohesion, and satisfaction in varsity athletes. PARTICIPANTS: Sixty-seven varsity athletes from a U-Sport Canadian university. METHODS: Athletes completed pre- and post-season measures of mental toughness, emotion regulation, self-control, group cohesion, and satisfaction. Multiple mediation models were employed during analyses. RESULTS: Pre-season emotion regulation was a significant mediator for the relationships between mental toughness and post-season ratings of perceived stress, perceived mental health, and group cohesion. Self-control was not a significant mediator. CONCLUSIONS: Emotion regulation plays a significant role in an athlete's experience of perceived stress, mental health issues, and their ratings of group cohesiveness. Research on student-athlete health may benefit from examining emotion regulation training techniques.


Assuntos
Autocontrole , Estudantes , Humanos , Estações do Ano , Canadá , Universidades , Atletas/psicologia
2.
Nurs Outlook ; 70(5): 710-724, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35933178

RESUMO

BACKGROUND: Nurse scientists have significantly contributed to health equity and ensuring cultural tailoring of interventions to meet unique needs of individuals. Methodologies for cultural tailoring of self-mangament interventions among marginalized populations have limitedly accommodated intersectionality and group heterogeneity when addressing health needs. PURPOSE: Identify methodological limitations in cultural tailoring of interventions among priority populations and issue recommendations on cultural elements that researchers can target to ensure valid cultural tailoring approaches. METHODS: Synthesis of literature on health equity, self-management, and implementation and dissemination research. FINDINGS: Among priority populations, intersectionality and group heterogeneity has made group-based cultural tailoring approaches less effective in eliciting desirable health outcomes. Precision health methodology could be useful for cultural tailoring of interventions due to the methodology's focus on individual-level tailoring approaches. DISCUSSION: We offer ways to advance health equity research using precision health approaches in cultural tailoring through targeting unique elements of culture and relevant psychosocial phenotypes.


Assuntos
Equidade em Saúde , Autogestão , Humanos , Medicina de Precisão , Coleta de Dados
3.
Sci Rep ; 11(1): 14397, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257348

RESUMO

T-cell-redirecting bispecific antibodies have emerged as a new class of therapeutic agents designed to simultaneously bind to T cells via CD3 and to tumor cells via tumor-cell-specific antigens (TSA), inducing T-cell-mediated killing of tumor cells. The promising preclinical and clinical efficacy of TSAxCD3 antibodies is often accompanied by toxicities such as cytokine release syndrome due to T-cell activation. How the efficacy and toxicity profile of the TSAxCD3 bispecific antibodies depends on the binding affinity to CD3 remains unclear. Here, we evaluate bispecific antibodies that were engineered to have a range of CD3 affinities, while retaining the same binding affinity for the selected tumor antigen. These agents were tested for their ability to kill tumor cells in vitro, and their biodistribution, serum half-life, and anti-tumor activity in vivo. Remarkably, by altering the binding affinity for CD3 alone, we can generate bispecific antibodies that maintain potent killing of TSA + tumor cells but display differential patterns of cytokine release, pharmacokinetics, and biodistribution. Therefore, tuning CD3 affinity is a promising method to improve the therapeutic index of T-cell-engaging bispecific antibodies.


Assuntos
Anticorpos Biespecíficos , Complexo CD3 , Citocinas , Citocinas/metabolismo , Ativação Linfocitária , Distribuição Tecidual
4.
Mol Cancer Ther ; 20(8): 1350-1358, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34045228

RESUMO

Immunotherapies to treat cancer have made tremendous progress over the past decade. In particular, T cell-directed therapies have gained considerable attention with CD3 bispecific antibodies and CAR T cells showing potent responses against hematologic tumors. At present, the ability to adapt these therapeutics to treat solid tumors is less established. Herein, we discuss recent advances in T cell-engaging CD3 bispecific antibodies targeting solid tumors, potential mechanisms of resistance, and future prospects. A better understanding of the mechanisms of immune evasion in solid tumors will enable the development of strategies to overcome this resistance and inform choices of therapeutic combinations.


Assuntos
Anticorpos Biespecíficos/farmacologia , Complexo CD3/imunologia , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Animais , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia
5.
Can Urol Assoc J ; 15(10): 326-331, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33750522

RESUMO

INTRODUCTION: Evidence-based psychological strategies are being used as clinicians look for helpful interventions for patients diagnosed with the enigmatic chronic urological pelvic pain condition of interstitial cystitis/bladder pain syndrome (IC/BPS). Pain and pain catastrophizing are associated with chronic pelvic pain outcomes but the longitudinal role of catastrophizing on patient pain in IC/BPS remains unknown. METHODS: Women with IC/BPS were recruited from tertiary care clinics across North America and completed a battery of questionnaires, including demographics, pain, depression, catastrophizing at baseline, six months, and one year. RESULTS: A total of 226 patients completed baseline questions, 183 completed the six-month survey, and 151 completed the one-year survey. Using a cross-lagged analysis, early changes in pain catastrophizing predicted later changes in pain, but not vice versa. Followup subscale analyses revealed that early changes in magnification predicted later changes in pain, early changes in pain predicted later changes in rumination, and that there was a recursive relationship between changes in helplessness and changes in pain across the study. CONCLUSIONS: Pain catastrophizing should be considered a prime target in psychological treatment for chronic pain in patients with IC/BPS, particularly those thinking styles associated with pain onset and maintenance. Future research should be conducted with constructs such as pain catastrophizing in samples prioritizing diversity of patients with IC/BPS and mechanisms as to how to effectively decrease catastrophizing.

6.
Cancer Immunol Res ; 8(5): 596-608, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32184296

RESUMO

Patients with hematologic cancers have improved outcomes after treatment with bispecific antibodies that bind to CD3 on T cells and that redirect T cells toward cancer cells. However, clinical benefit against solid tumors remains to be shown. We made a bispecific antibody that targets both the common prostate tumor-specific antigen PSMA and CD3 (PMSAxCD3) and provide evidence for tumor inhibition in several preclinical solid tumor models. Mice expressing the human extracellular regions of CD3 and PSMA were generated to examine antitumor efficacy in the presence of an intact immune system and PSMA expression in normal tissues. PSMAxCD3 accumulated in PSMA-expressing tissues and tumors as detected by immuno-PET imaging. Although PSMAxCD3 induced T-cell activation and showed antitumor efficacy in mice with low tumor burden, PSMAxCD3 lost efficacy against larger solid tumors, mirroring the difficulty of treating solid tumors in the clinic. Costimulatory receptors can enhance T-cell responses. We show here that costimulation can enhance the antitumor efficacy of PSMAxCD3. In particular, 4-1BB stimulation in combination with PSMAxCD3 enhanced T-cell activation and proliferation, boosted efficacy against larger tumors, and induced T-cell memory, leading to durable antitumor responses. The combination of CD3 bispecific antibodies and anti-4-1BB costimulation represents a therapeutic approach for the treatment of solid tumors.


Assuntos
Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais/farmacologia , Complexo CD3/imunologia , Glutamato Carboxipeptidase II/antagonistas & inibidores , Neoplasias da Próstata/tratamento farmacológico , Linfócitos T/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Anticorpos Biespecíficos/imunologia , Antígenos de Superfície/imunologia , Antígenos de Superfície/metabolismo , Complexo CD3/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glutamato Carboxipeptidase II/imunologia , Glutamato Carboxipeptidase II/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Radioisótopos/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Zircônio/farmacocinética
7.
Sci Transl Med ; 12(525)2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915305

RESUMO

T cell activation is initiated upon binding of the T cell receptor (TCR)/CD3 complex to peptide-major histocompatibility complexes ("signal 1"); activation is enhanced by engagement of a second "costimulatory" receptor, such as the CD28 receptor on T cells binding to its cognate ligand(s) on the target cell ("signal 2"). CD3-based bispecific antibodies act by replacing conventional signal 1, linking T cells to tumor cells by binding a tumor-specific antigen (TSA) with one arm of the bispecific and bridging to TCR/CD3 with the other. Although some of these so-called TSAxCD3 bispecifics have demonstrated promising antitumor efficacy in patients with cancer, their activity remains to be optimized. Here, we introduce a class of bispecific antibodies that mimic signal 2 by bridging TSA to the costimulatory CD28 receptor on T cells. We term these TSAxCD28 bispecifics and describe two such bispecific antibodies: one specific for ovarian and the other for prostate cancer antigens. Unlike CD28 superagonists, which broadly activate T cells and resulted in profound toxicity in early clinical trials, these TSAxCD28 bispecifics show limited activity and no toxicity when used alone in genetically humanized immunocompetent mouse models or in primates. However, when combined with TSAxCD3 bispecifics, they enhance the artificial synapse between a T cell and its target cell, potentiate T cell activation, and markedly improve antitumor activity of CD3 bispecifics in a variety of xenogeneic and syngeneic tumor models. Combining this class of CD28-costimulatory bispecific antibodies with the emerging class of TSAxCD3 bispecifics may provide well-tolerated, off-the-shelf antibody therapies with robust antitumor efficacy.


Assuntos
Anticorpos Biespecíficos/imunologia , Antígenos CD28/imunologia , Complexo CD3/imunologia , Neoplasias/imunologia , Animais , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Citotoxicidade Imunológica , Feminino , Células HEK293 , Humanos , Sinapses Imunológicas/metabolismo , Ativação Linfocitária/imunologia , Macaca fascicularis , Camundongos , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Can Urol Assoc J ; 13(10): 328-333, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31364973

RESUMO

INTRODUCTION: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a devastating urological chronic pelvic pain condition with an unknown etiology. Evidence-based psychological strategies are becoming more successful for symptom management as we learn more about the targets for intervention. Previous research has established an indirect relationship between depression and pain through catastrophizing, but there have yet to be studies examining the emerging role of emotion regulation in this relationship. METHODS: Women with IC/BPS were recruited from tertiary care clinics in Canada and the U.S. between 2013 and 2018. Patients completed questionnaires, including demographics and scores for pain, depression, catastrophizing, and difficulties in emotion regulation at baseline, six months, and one year. Serial mediation was used to test models of pain, catastrophizing, and depression. RESULTS: A total of 135 women with IC/BPS completed all three time points. The only significant indirect path was from baseline depression to catastrophizing at six months to pain at one year (b=0.10; confidence interval [CI] 0.0049-0.2520). A followup analysis demonstrated that helplessness was the key factor of catastrophizing driving this relationship (b=0.17; CI 0.0282-0.3826). CONCLUSIONS: Reducing feelings of helplessness and increasing patient feelings of control are important ways to limit the effect of low mood on patient pain experience. De-catastrophizing interventions should be part of the referral strategy for IC/BPS symptom management.

9.
Sci Transl Med ; 11(497)2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217340

RESUMO

Advanced ovarian cancer is frequently treated with combination chemotherapy, but high recurrence rates show the need for therapies that can produce durable responses and extend overall survival. Bispecific antibodies that interact with tumor antigens on cancer cells and activating receptors on immune cells offer an innovative immunotherapy approach. Here, we describe a human bispecific antibody (REGN4018) that binds both Mucin 16 (MUC16), a glycoprotein that is highly expressed on ovarian cancer cells, and CD3, thus bridging MUC16-expressing cells with CD3+ T cells. REGN4018 induced T cell activation and killing of MUC16-expressing tumor cells in vitro. Binding and cytotoxicity of REGN4018 in vitro were minimally affected by high concentrations of CA-125, the shed form of MUC16, which is present in patients. In preclinical studies with human ovarian cancer cells and human T cells in immunodeficient mice, REGN4018 potently inhibited growth of intraperitoneal ovarian tumors. Moreover, in a genetically engineered immunocompetent mouse expressing human CD3 and human MUC16 [humanized target (HuT) mice], REGN4018 inhibited growth of murine tumors expressing human MUC16, and combination with an anti-PD-1 antibody enhanced this efficacy. Immuno-PET imaging demonstrated localization of REGN4018 in MUC16-expressing tumors and in T cell-rich organs such as the spleen and lymph nodes. Toxicology studies in cynomolgus monkeys showed minimal and transient increases in serum cytokines and C-reactive protein after REGN4018 administration, with no overt toxicity. Collectively, these data demonstrate potent antitumor activity and good tolerability of REGN4018, supporting clinical evaluation of REGN4018 in patients with MUC16-expressing advanced ovarian cancer.


Assuntos
Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/uso terapêutico , Antígeno Ca-125/imunologia , Antígeno Ca-125/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/imunologia , Linfócitos T/metabolismo , Animais , Antígenos CD13/imunologia , Antígenos CD13/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Células Jurkat , Macaca fascicularis , Camundongos , Neoplasias Ovarianas/metabolismo , Linfócitos T/imunologia
10.
Australas Psychiatry ; 24(2): 173-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26400454

RESUMO

OBJECTIVES: To detail a diagnostic dilemma of intentional hand amputation in a man with a history of substance misuse and associated psychosis, depression and traumatic brain injury and to highlight issues in joint psychiatric and surgical management of such a complex patient in a general hospital setting. CONCLUSIONS: Deliberate limb self-amputation is a rare event with the majority of reported cases occurring during an episode of psychosis. This case illustrates the diagnostic utility of the literature supporting that a person who has self-inflicted amputation of a limb should be treated as psychotic until proven otherwise. The presence of a traumatic brain injury, with associated cognitive and psychosocial sequelae, affected diagnosis and management. Early and ongoing involvement of consultation-liaison psychiatry collaborating with a multidisciplinary general hospital team may improve mental and physical health outcomes for such patients.


Assuntos
Amputação Cirúrgica/psicologia , Gerenciamento Clínico , Transtornos Psicóticos/diagnóstico , Comportamento Autodestrutivo/diagnóstico , Hospitais Gerais , Humanos , Masculino , Transtornos Psicóticos/complicações , Encaminhamento e Consulta , Comportamento Autodestrutivo/complicações , Comportamento Autodestrutivo/terapia , Adulto Jovem
12.
Cancer Res ; 74(8): 2171-81, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24590059

RESUMO

Recent advances in cancer immunotherapy suggest that manipulation of the immune system to enhance the antitumor response may be a highly effective treatment modality. One understudied aspect of immunosurveillance is antiangiogenic surveillance, the regulation of tumor angiogenesis by the immune system, independent of tumor cell lysis. CD4(+) T cells can negatively regulate angiogenesis by secreting antiangiogenic factors such as thrombospondin-1 (TSP-1). In tumor-bearing mice, we show that a Th1-directed viral infection that triggers upregulation of TSP-1 in CD4(+) and CD8(+) T cells can inhibit tumor angiogenesis and suppress tumor growth. Using bone marrow chimeras and adoptive T-cell transfers, we demonstrated that TSP-1 expression in the T-cell compartment was necessary and sufficient to inhibit tumor growth by suppressing tumor angiogenesis after the viral infection. Our results establish that tumorigenesis can be stanched by antiangiogenic surveillance triggered by an acute viral infection, suggesting novel immunologic approaches to achieve antiangiogenic therapy.


Assuntos
Imunoterapia Adotiva/métodos , Melanoma Experimental/terapia , Linfócitos T/imunologia , Trombospondina 1/imunologia , Animais , Carcinogênese/imunologia , Técnicas de Cultura de Células , Vigilância Imunológica , Ativação Linfocitária , Masculino , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Camundongos Transgênicos , Neovascularização Patológica/imunologia , Neovascularização Patológica/terapia , Trombospondina 1/biossíntese , Trombospondina 1/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Atherosclerosis ; 233(1): 234-41, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24529150

RESUMO

Apolipoprotein F (ApoF) is a sialoglycoprotein that is a component of the HDL and LDL fractions of human serum. We sought to test the hypothesis that ApoF plays an important role in atherosclerosis in mice by modulating lipoprotein function. Atherosclerosis was assessed in male low density lipoprotein receptor knockout (Ldlr KO) and ApoF/Ldlr double knockout (DKO) mice fed a Western diet for 16 weeks. ApoF/Ldlr DKO mice showed a 39% reduction in lesional area by en face analysis of aortas (p < 0.05), despite no significant differences in plasma lipid parameters. ApoF KO mice had reduced expression of Interferon alpha (IFNα) responsive genes in liver and spleen, as well as impaired macrophage activation. Interferon alpha induced gene 27 like 2a (Ifi27l2a), Oligoadenylate synthetases 2 and 3 (Oas2 and Oas3) were significantly reduced in the ApoF KO mice relative to wild type controls. These effects were attributable to hypomorphic expression of Stat2 in the ApoF KO mice, a critical gene in the Type I IFN pathway that is situated just 425 base pairs downstream of ApoF. These studies implicate STAT2 as a potentially important player in atherosclerosis, and support the growing evidence that the Type I IFN pathway may contribute to this complex disease.


Assuntos
Apolipoproteínas/genética , Aterosclerose/fisiopatologia , Interferon Tipo I/fisiologia , Receptores de LDL/genética , Fator de Transcrição STAT2/genética , Transdução de Sinais/fisiologia , Animais , Aorta/patologia , Aterosclerose/genética , Aterosclerose/patologia , Masculino , Camundongos , Camundongos Knockout
14.
Immunity ; 40(2): 289-302, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24530057

RESUMO

T cell exhaustion is common during chronic infections. Although CD4(+) T cells are critical for controlling viral load during chronic viral infections, less is known about their differentiation and transcriptional program. We defined the phenotypic, functional, and molecular profiles of exhausted CD4(+) T cells. Global transcriptional analysis demonstrated a molecular profile distinct from effector and memory CD4(+) T cells and also from exhausted CD8(+) T cells, though some common features of CD4(+) and CD8(+) T cell exhaustion were revealed. We have demonstrated unappreciated roles for transcription factors (TFs) including Helios, type I interferon (IFN-I) signaling, and a diverse set of coinhibitory and costimulatory molecules during CD4(+) T cell exhaustion. Moreover, the signature of CD4(+) T cell exhaustion was found to be distinct from that of other CD4(+) T cell lineage subsets and was associated with TF heterogeneity. This study provides a framework for therapeutic interventions targeting exhausted CD4(+) T cells.


Assuntos
Infecções Bacterianas/imunologia , Linfócitos T CD4-Positivos/imunologia , Doenças Transmissíveis/imunologia , Viroses/imunologia , Carga Bacteriana , Linfócitos T CD4-Positivos/citologia , Doença Crônica , Doenças Transmissíveis/fisiopatologia , Humanos , Carga Viral
15.
Mol Ther ; 22(1): 28-41, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23778424

RESUMO

Following gene transfer of adeno-associated virus 2/8 (AAV2/8) to the muscle, C57BL/6 mice show long-term expression of a nuclear-targeted LacZ (nLacZ) transgene with minimal immune activation. Here, we show that pre-exposure to AAV2/8 can also induce tolerance to the more immunogenic AAV2/rh32.33 vector, preventing otherwise robust T-cell activation and allowing stable transgene expression. Depletion and adoptive transfer studies showed that a suppressive factor was not sufficient to account for AAV2/8-induced tolerance, whereas further characterization of the T-cell population showed upregulation of the exhaustion markers PD1, 2B4, and LAG3. Furthermore, systemic administration of Toll-like receptor (TLR) ligands at the time of AAV2/rh32.33-administration broke AAV2/8-induced tolerance, restoring T-cell activation and ß-gal clearance. As such, AAV2/8 transduction appears to lack the inflammatory signals necessary to prime a functional cytotoxic T-cell response. Inadequate T-cell priming could be explained upstream by AAV2/8's poor transduction and activation of antigen-presenting cells (APCs). Immunohistochemical analysis indicates that AAV2/8 transduction also fails to upregulate major histocompatibility complex class I (MHCI) expression on the surface of myocytes, rendering transduced cells poor targets for T-cell-mediated destruction. Overall, AAV2/8-induced tolerance in the muscle is multifactorial, spanning from poor APC transduction and activation to the subsequent priming of functionally exhausted T-cells, while simultaneously avoiding upregulation of MHCI on potential targets.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Dependovirus/imunologia , Vetores Genéticos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Tolerância Imunológica , Músculo Esquelético/imunologia , Subpopulações de Linfócitos T/imunologia , Transdução Genética , Animais , Células Apresentadoras de Antígenos/metabolismo , Dependovirus/genética , Expressão Gênica , Vetores Genéticos/genética , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Receptores Toll-Like/metabolismo , Transgenes/genética , Transgenes/imunologia
16.
Nature ; 498(7452): 113-7, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23698371

RESUMO

Innate lymphoid cells (ILCs) are a recently characterized family of immune cells that have critical roles in cytokine-mediated regulation of intestinal epithelial cell barrier integrity. Alterations in ILC responses are associated with multiple chronic human diseases, including inflammatory bowel disease, implicating a role for ILCs in disease pathogenesis. Owing to an inability to target ILCs selectively, experimental studies assessing ILC function have predominantly used mice lacking adaptive immune cells. However, in lymphocyte-sufficient hosts ILCs are vastly outnumbered by CD4(+) T cells, which express similar profiles of effector cytokines. Therefore, the function of ILCs in the presence of adaptive immunity and their potential to influence adaptive immune cell responses remain unknown. To test this, we used genetic or antibody-mediated depletion strategies to target murine ILCs in the presence of an adaptive immune system. We show that loss of retinoic-acid-receptor-related orphan receptor-γt-positive (RORγt(+)) ILCs was associated with dysregulated adaptive immune cell responses against commensal bacteria and low-grade systemic inflammation. Remarkably, ILC-mediated regulation of adaptive immune cells occurred independently of interleukin (IL)-17A, IL-22 or IL-23. Genome-wide transcriptional profiling and functional analyses revealed that RORγt(+) ILCs express major histocompatibility complex class II (MHCII) and can process and present antigen. However, rather than inducing T-cell proliferation, ILCs acted to limit commensal bacteria-specific CD4(+) T-cell responses. Consistent with this, selective deletion of MHCII in murine RORγt(+) ILCs resulted in dysregulated commensal bacteria-dependent CD4(+) T-cell responses that promoted spontaneous intestinal inflammation. These data identify that ILCs maintain intestinal homeostasis through MHCII-dependent interactions with CD4(+) T cells that limit pathological adaptive immune cell responses to commensal bacteria.


Assuntos
Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Imunidade Inata/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Simbiose , Animais , Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Inflamação/patologia , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Interleucinas/metabolismo , Intestinos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Interleucina 22
17.
Immunity ; 37(6): 1130-44, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23159438

RESUMO

Exhausted CD8(+) T cells function poorly and are negatively regulated by inhibitory receptors. Transcriptional profiling has identified gene expression changes associated with exhaustion. However, the transcriptional pathways critical to the differences between exhausted and functional memory CD8(+) T cells are unclear. We thus defined transcriptional coexpression networks to define pathways centrally involved in exhaustion versus memory. These studies revealed differences between exhausted and memory CD8(+) T cells including the following: lack of coordinated transcriptional modules of quiescence during exhaustion, centrally connected hub genes, pathways such as transcription factors, genes involved in regulation of immune responses, and DNA repair genes, as well as differential connectivity for genes including T-bet, Eomes, and other transcription factors. These data identify pathways involved in CD8(+) T cell exhaustion, and highlight the context-dependent nature of transcription factors in exhaustion versus memory.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Memória Imunológica/genética , Transdução de Sinais , Doença Aguda , Animais , Doença Crônica , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Fatores de Transcrição/genética , Transcrição Gênica
18.
J Virol ; 86(15): 8161-70, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22623779

RESUMO

T cell exhaustion and loss of memory potential occur during many chronic viral infections and cancer. We investigated when during chronic viral infection virus-specific CD8 T cells lose the potential to form memory. Virus-specific CD8 T cells from established chronic infection were unable to become memory CD8 T cells if removed from infection. However, at earlier stages of chronic infection, these virus-specific CD8 T cells retained the potential to partially or fully revert to a memory differentiation program after transfer to infection-free mice. Conversely, effector CD8 T cells primed during acute infection were not protected from exhaustion if transferred to a chronic infection. We also tested whether memory and exhausted CD8 T cells arose from different subpopulations of effector CD8 T cells and found that only the KLRG1(lo) memory precursor subset gave rise to exhausted CD8 T cells. Together, these studies demonstrate that CD8 T cell exhaustion is a progressive developmental process. Early during chronic infection, the fate of virus-specific CD8 T cells remains plastic, while later, exhausted CD8 T cells become fixed in their differentiation state. Moreover, exhausted CD8 T cells arise from the memory precursor and not the terminally differentiated subset of effector CD8 T cells. These studies have implications for our understanding of senescence versus exhaustion and for therapeutic interventions during chronic infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Memória Imunológica , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Células Precursoras de Linfócitos T/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , Doença Crônica , Lectinas Tipo C , Coriomeningite Linfocítica/patologia , Camundongos , Células Precursoras de Linfócitos T/patologia , Receptores Imunológicos/imunologia
19.
PLoS Pathog ; 7(7): e1002098, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21814510

RESUMO

RANTES (CCL5) is a chemokine expressed by many hematopoietic and non-hematopoietic cell types that plays an important role in homing and migration of effector and memory T cells during acute infections. The RANTES receptor, CCR5, is a major target of anti-HIV drugs based on blocking viral entry. However, defects in RANTES or RANTES receptors including CCR5 can compromise immunity to acute infections in animal models and lead to more severe disease in humans infected with west Nile virus (WNV). In contrast, the role of the RANTES pathway in regulating T cell responses and immunity during chronic infection remains unclear. In this study, we demonstrate a crucial role for RANTES in the control of systemic chronic LCMV infection. In RANTES⁻/⁻ mice, virus-specific CD8 T cells had poor cytokine production. These RANTES⁻/⁻ CD8 T cells also expressed higher amounts of inhibitory receptors consistent with more severe exhaustion. Moreover, the cytotoxic ability of CD8 T cells from RANTES⁻/⁻ mice was reduced. Consequently, viral load was higher in the absence of RANTES. The dysfunction of T cells in the absence of RANTES was as severe as CD8 T cell responses generated in the absence of CD4 T cell help. Our results demonstrate an important role for RANTES in sustaining CD8 T cell responses during a systemic chronic viral infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Quimiocina CCL5/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Receptores CCR5/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Quimiocina CCL5/genética , Doença Crônica , Humanos , Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/genética , Camundongos , Camundongos Knockout , Receptores CCR5/genética , Carga Viral/genética , Carga Viral/imunologia , Febre do Nilo Ocidental/genética , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/imunologia
20.
Nat Immunol ; 12(7): 663-71, 2011 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-21623380

RESUMO

T cell exhaustion has a major role in failure to control chronic infection. High expression of inhibitory receptors, including PD-1, and the inability to sustain functional T cell responses contribute to exhaustion. However, the transcriptional control of these processes remains unclear. Here we demonstrate that the transcription factor T-bet regulated the exhaustion of CD8(+) T cells and the expression of inhibitory receptors. T-bet directly repressed transcription of the gene encoding PD-1 and resulted in lower expression of other inhibitory receptors. Although a greater abundance of T-bet promoted terminal differentiation after acute infection, high T-bet expression sustained exhausted CD8(+) T cells and repressed the expression of inhibitory receptors during chronic viral infection. Persistent antigenic stimulation caused downregulation of T-bet, which resulted in more severe exhaustion of CD8(+) T cells. Our observations suggest therapeutic opportunities involving higher T-bet expression during chronic infection.


Assuntos
Antígenos de Diferenciação/imunologia , Coriomeningite Linfocítica/imunologia , Proteínas com Domínio T/imunologia , Animais , Antígenos de Diferenciação/genética , Antígenos Virais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Doença Crônica , Ativação Linfocitária/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1 , Transcrição Gênica/imunologia
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