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1.
Nat Immunol ; 19(9): 963-972, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30082830

RESUMO

Clonal expansion and immunological memory are hallmark features of the mammalian adaptive immune response and essential for prolonged host control of pathogens. Recent work demonstrates that natural killer (NK) cells of the innate immune system also exhibit these adaptive traits during infection. Here we demonstrate that differentiating and 'memory' NK cells possess distinct chromatin accessibility states and that their epigenetic profiles reveal a 'poised' regulatory program at the memory stage. Furthermore, we elucidate how individual STAT transcription factors differentially control epigenetic and transcriptional states early during infection. Finally, concurrent chromatin profiling of the canonical CD8+ T cell response against the same infection demonstrated parallel and distinct epigenetic signatures defining NK cells and CD8+ T cells. Overall, our study reveals the dynamic nature of epigenetic modifications during the generation of innate and adaptive lymphocyte memory.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Cromatina/metabolismo , Infecções por Herpesviridae/imunologia , Células Matadoras Naturais/fisiologia , Muromegalovirus/fisiologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT4/metabolismo , Imunidade Adaptativa , Animais , Células Cultivadas , Cromatina/genética , Seleção Clonal Mediada por Antígeno , Epigênese Genética , Perfilação da Expressão Gênica , Imunidade Inata , Memória Imunológica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT4/genética
2.
Immunity ; 48(6): 1172-1182.e6, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29858012

RESUMO

Natural killer (NK) cells are innate lymphocytes that display features of adaptive immunity during viral infection. Biallelic mutations in IRF8 have been reported to cause familial NK cell deficiency and susceptibility to severe viral infection in humans; however, the precise role of this transcription factor in regulating NK cell function remains unknown. Here, we show that cell-intrinsic IRF8 was required for NK-cell-mediated protection against mouse cytomegalovirus infection. During viral exposure, NK cells upregulated IRF8 through interleukin-12 (IL-12) signaling and the transcription factor STAT4, which promoted epigenetic remodeling of the Irf8 locus. Moreover, IRF8 facilitated the proliferative burst of virus-specific NK cells by promoting expression of cell-cycle genes and directly controlling Zbtb32, a master regulator of virus-driven NK cell proliferation. These findings identify the function and cell-type-specific regulation of IRF8 in NK-cell-mediated antiviral immunity and provide a mechanistic understanding of viral susceptibility in patients with IRF8 mutations.


Assuntos
Imunidade Adaptativa/imunologia , Fatores Reguladores de Interferon/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária/imunologia , Animais , Infecções por Herpesviridae/imunologia , Camundongos , Muromegalovirus/imunologia
3.
Immunity ; 45(2): 428-41, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27496734

RESUMO

Innate lymphoid cells (ILCs) function to protect epithelial barriers against pathogens and maintain tissue homeostasis in both barrier and non-barrier tissues. Here, utilizing Eomes reporter mice, we identify a subset of adipose group 1 ILC (ILC1) and demonstrate a role for these cells in metabolic disease. Adipose ILC1s were dependent on the transcription factors Nfil3 and T-bet but phenotypically and functionally distinct from adipose mature natural killer (NK) and immature NK cells. Analysis of parabiotic mice revealed that adipose ILC1s maintained long-term tissue residency. Diet-induced obesity drove early production of interleukin (IL)-12 in adipose tissue depots and led to the selective proliferation and accumulation of adipose-resident ILC1s in a manner dependent on the IL-12 receptor and STAT4. ILC1-derived interferon-γ was necessary and sufficient to drive proinflammatory macrophage polarization to promote obesity-associated insulin resistance. Thus, adipose-resident ILC1s contribute to obesity-related pathology in response to dysregulated local proinflammatory cytokine production.


Assuntos
Tecido Adiposo/imunologia , Resistência à Insulina/imunologia , Linfócitos/imunologia , Macrófagos/imunologia , Obesidade/imunologia , Proteínas com Domínio T/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Interferon gama/metabolismo , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Proteínas com Domínio T/genética
4.
J Immunol ; 205(8): 2056-2065, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32907996

RESUMO

CCL22 is a key mediator of leukocyte trafficking in inflammatory immune responses, allergy, and cancer. It acts by attracting regulatory T cells and Th2 cells via their receptor CCR type 4 (CCR4). Beyond its role in inflammation, CCL22 is constitutively expressed at high levels in lymphoid organs during homeostasis, where it controls immunity by recruiting regulatory T cells to dendritic cells (DCs). In this study, we aimed to identify the mechanisms responsible for constitutive CCL22 expression. We confirmed that CD11c+ DCs are the exclusive producers of CCL22 in secondary lymphatic organs during homeostasis. We show that in vitro both murine splenocytes and human PBMCs secrete CCL22 spontaneously without any further stimulation. Interestingly, isolated DCs alone, however, are unable to produce CCL22, but instead require T cell help. In vitro, only the coculture of DCs with T cells or their supernatants resulted in CCL22 secretion, and we identified T cell-derived GM-CSF as the major inducer of DC-derived CCL22 expression. In vivo, Rag1 -/- mice, which lack functional T cells, have low CCL22 levels in lymphoid organs, and this can be restored by adoptive transfer of wild-type T cells or administration of GM-CSF. Taken together, we uncover T cell-derived GM-CSF as a key inducer of the chemokine CCL22 and thus, to our knowledge, identify a novel role for this cytokine as a central regulator of immunity in lymphatic organs. This knowledge could contribute to the development of new therapeutic interventions in cancer and autoimmunity.


Assuntos
Quimiocina CCL22/imunologia , Células Dendríticas/imunologia , Regulação da Expressão Gênica/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Linfócitos T Reguladores/imunologia , Animais , Antígenos CD11/genética , Antígenos CD11/imunologia , Quimiocina CCL22/genética , Células Dendríticas/citologia , Hormônio Liberador de Gonadotropina/análogos & derivados , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Camundongos Knockout , Linfócitos T Reguladores/citologia , Células Th2/citologia , Células Th2/imunologia
5.
J Immunother Cancer ; 10(3)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35292514

RESUMO

Tumor-targeted CD40 agonism represents an attractive strategy for cancer immunotherapy (CIT) as it promotes dendritic cell (DC) activation and concomitant tumor-specific T cell priming without causing systemic side effects. We developed the bispecific CD40 agonistic antibody CEA-CD40, which triggers CD40 stimulation exclusively in the presence of carcinoembryonic antigen (CEA), a glycoprotein specifically expressed on tumor cells. In this study, we demonstrate that CEA-CD40 can enable potent in vitro DC activation and consecutive T cell cross-priming in a CEA-specific manner. Furthermore, we provide evidence that CEA-CD40 increases colocalization of CEA+ tumor material and DCs. Using CEA+ tumor-derived extracellular vesicles (EVs), which are known to be an excellent tumor antigen source, we show that CEA-CD40 mediates delivery of CEA+ EVs to DCs. Importantly, our data indicates that this fosters acquisition of tumor EV major histocompatibility complex I/peptide complexes by DCs, consequently improving CD8+ T cell priming against EV-associated antigen in vitro. Thus, we provide mechanistic evidence for a dual mode of action of CEA-CD40 for CIT: we suggest that CEA-CD40 has the potential to activate DCs and in addition can promote their loading with tumor antigen derived from EVs to trigger tumor-specific T cell cross-priming.


Assuntos
Antígeno Carcinoembrionário , Neoplasias , Antígenos CD40 , Linfócitos T CD8-Positivos , Células Dendríticas , Humanos , Neoplasias/terapia
6.
Int J Cancer ; 129(10): 2417-26, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21207371

RESUMO

Regulatory T cells (Treg) mediate tolerance towards self-antigens by suppression of innate and adaptive immunity. In cancer patients, tumor-infiltrating FoxP3+ Treg suppress local anti-tumor immune responses and are often associated with poor prognosis. Markers that are selectively expressed on tumor-infiltrating Treg may serve as targets for immunotherapy of cancer. Here we show that CD103, an integrin mediating lymphocyte retention in epithelial tissues, is expressed at high levels on tumor-infiltrating FoxP3+ Treg in several types of murine cancer. In the CT26 model of colon cancer up to 90% of the intratumoral FoxP3+ cells expressed CD103 compared to less than 20% in lymphoid organs. CD103+ Treg suppressed T effector cell activation more strongly than CD103(neg) Treg. Expression of CD103 on Treg closely correlated with intratumoral levels of transforming growth factor ß (TGF-ß) and could be induced in a TGF-ß-dependent manner by tumor cell lines. In vivo, gene silencing of TGF-ß reduced the frequency of CD103+ Treg, demonstrating that CD103 expression on tumor-infiltrating Treg is driven by intratumoral TGF-ß. Functional blockade of CD103 using a monoclonal antibody did however not reduce the number of intratumoral Treg, indicating that CD103 is not involved in homing or retention of FoxP3+ cells in the tumor tissue. In conclusion, expression of CD103 is a hallmark of Treg that infiltrate TGF-ß-secreting tumors. CD103 thus represents an interesting target for selective depletion of tumor-infiltrating Treg, a strategy that may help to improve anti-cancer therapy.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Animais , Antígenos CD , Linhagem Celular Tumoral , Feminino , Cadeias alfa de Integrinas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores , Fator de Crescimento Transformador beta/metabolismo
7.
Clin Cancer Res ; 27(14): 4054-4065, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33903200

RESUMO

PURPOSE: The incidence of human papillomavirus-associated head and neck squamous cell carcinoma (HPV+-HNSCC) is rising worldwide and although current therapeutic modalities are efficient in the majority of patients, there is a high rate of treatment failures. Thus, novel combination approaches are urgently needed to achieve better disease control in patients with HPV+-HNSCC. We investigated the safety and therapeutic efficacy of a novel fibroblast activation protein (FAP)-targeted CD40 agonist (FAP-CD40) in combination with local hypofractionated radiation in a syngeneic HPV+-HNSCC model. EXPERIMENTAL DESIGN: Using an established orthotopic model, we treated tumor-bearing mice with local hypofractionated radiotherapy (2 × 6 Gy) alone or in combination with a systemic administration of the FAP-CD40 antibody. Following up the mice, we evaluated the changes in the tumor microenvironment (TME) by immunofluorescence, FACS, and NanoString RNA analysis. RESULTS: The suboptimal radiotherapy regimen chosen failed to control tumors in the treated mice. The FAP-CD40 administered in monotherapy transiently controlled tumor growth, whereas the combined therapy induced durable complete responses in more than 80% of the tumor-bearing mice. This notable efficacy relied on the radiotherapy-induced remodeling of the TME and activation of the CD8+ T-cell-cDC1 axis and was devoid of the systemic toxicity frequently associated with CD40-targeted therapy. Moreover, the robust immunologic memory developed effectively prevented tumor relapses, a common feature in patients with HNSCC. CONCLUSIONS: Our study provides proof of concept, as well as mechanistic insights of the therapeutic efficacy of a bispecific FAP-CD40 combined with local radiotherapy in a FAP+-HNSCC model increasing overall survival and inducing long-term antitumor immunity.


Assuntos
Antígenos CD40/agonistas , Endopeptidases/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/virologia , Proteínas de Membrana/efeitos dos fármacos , Papillomaviridae/isolamento & purificação , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Animais , Terapia Combinada , Camundongos
8.
Clin Cancer Res ; 27(14): 4036-4053, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33771854

RESUMO

PURPOSE: CD40 agonists hold great promise for cancer immunotherapy (CIT) as they enhance dendritic cell (DC) activation and concomitant tumor-specific T-cell priming. However, the broad expression of CD40 accounts for sink and side effects, hampering the efficacy of anti-CD40 antibodies. We hypothesized that these limitations can be overcome by selectively targeting CD40 agonism to the tumor. Therefore, we developed a bispecific FAP-CD40 antibody, which induces CD40 stimulation solely in presence of fibroblast activation protein α (FAP), a protease specifically expressed in the tumor stroma. EXPERIMENTAL DESIGN: FAP-CD40's in vitro activity and FAP specificity were validated by antigen-presenting cell (APC) activation and T-cell priming assays. In addition, FAP-CD40 was tested in subcutaneous MC38-FAP and KPC-4662-huCEA murine tumor models. RESULTS: FAP-CD40 triggered a potent, strictly FAP-dependent CD40 stimulation in vitro. In vivo, FAP-CD40 strongly enhanced T-cell inflammation and growth inhibition of KPC-4662-huCEA tumors. Unlike nontargeted CD40 agonists, FAP-CD40 mediated complete regression of MC38-FAP tumors, entailing long-term protection. A high dose of FAP-CD40 was indispensable for these effects. While nontargeted CD40 agonists induced substantial side effects, highly dosed FAP-CD40 was well tolerated. FAP-CD40 preferentially accumulated in the tumor, inducing predominantly intratumoral immune activation, whereas nontargeted CD40 agonists displayed strong systemic but limited intratumoral effects. CONCLUSIONS: FAP-CD40 abrogates the systemic toxicity associated with nontargeted CD40 agonists. This enables administration of high doses, essential for overcoming CD40 sink effects and inducing antitumor immunity. Consequently, FAP-targeted CD40 agonism represents a promising strategy to exploit the full potential of CD40 signaling for CIT.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Antígenos CD40/agonistas , Endopeptidases/efeitos dos fármacos , Imunoterapia/métodos , Proteínas de Membrana/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Animais , Camundongos , Células Tumorais Cultivadas
9.
Nat Biomed Eng ; 5(11): 1246-1260, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34083764

RESUMO

The efficacy of adoptive cell therapy for solid tumours is hampered by the poor accumulation of the transferred T cells in tumour tissue. Here, we show that forced expression of C-X-C chemokine receptor type 6 (whose ligand is highly expressed by human and murine pancreatic cancer cells and tumour-infiltrating immune cells) in antigen-specific T cells enhanced the recognition and lysis of pancreatic cancer cells and the efficacy of adoptive cell therapy for pancreatic cancer. In mice with subcutaneous pancreatic tumours treated with T cells with either a transgenic T-cell receptor or a murine chimeric antigen receptor targeting the tumour-associated antigen epithelial cell adhesion molecule, and in mice with orthotopic pancreatic tumours or patient-derived xenografts treated with T cells expressing a chimeric antigen receptor targeting mesothelin, the T cells exhibited enhanced intratumoral accumulation, exerted sustained anti-tumoral activity and prolonged animal survival only when co-expressing C-X-C chemokine receptor type 6. Arming tumour-specific T cells with tumour-specific chemokine receptors may represent a promising strategy for the realization of adoptive cell therapy for solid tumours.


Assuntos
Imunoterapia Adotiva , Neoplasias Pancreáticas , Receptores CXCR6/metabolismo , Linfócitos T , Animais , Terapia Baseada em Transplante de Células e Tecidos , Mesotelina , Camundongos , Neoplasias Pancreáticas/terapia , Receptores de Quimiocinas/genética
10.
Cell Rep ; 33(11): 108498, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33326784

RESUMO

Natural killer (NK) cells are innate lymphocytes with the capacity to elicit adaptive features, including clonal expansion and immunological memory. Because signal transducer and activator of transcription 5 (STAT5) is essential for NK cell development, the roles of this transcription factor and its upstream cytokines interleukin-2 (IL-2) and IL-15 during infection have not been carefully investigated. In this study, we investigate how STAT5 regulates transcription during viral infection. We demonstrate that STAT5 is induced in NK cells by IL-12 and STAT4 early after infection and that partial STAT5 deficiency results in a defective capacity of NK cells to generate long-lived memory cells. Furthermore, we find a functional dichotomy of IL-2 and IL-15 signaling outputs during viral infection, whereby both cytokines drive clonal expansion, but only IL-15 is required for memory NK cell survival. We thus highlight a role for STAT5 signaling in promoting an optimal anti-viral NK cell response.


Assuntos
Células Matadoras Naturais/metabolismo , Fator de Transcrição STAT5/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
11.
J Exp Med ; 216(5): 1170-1181, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30910796

RESUMO

Chemokines have crucial roles in organ development and orchestration of leukocyte migration. The chemokine CCL22 is expressed constitutively at high levels in the lymph node, but the functional significance of this expression is so far unknown. Studying a newly established CCL22-deficient mouse, we demonstrate that CCL22 expression by dendritic cells (DCs) promotes the formation of cell-cell contacts and interaction with regulatory T cells (T reg) through their CCR4 receptor. Vaccination of CCL22-deficient mice led to excessive T cell responses that were also observed when wild-type mice were vaccinated using CCL22-deficient DCs. Tumor-bearing mice with CCL22 deficiency showed prolonged survival upon vaccination, and further, CCL22-deficient mice had increased susceptibility to inflammatory disease. In conclusion, we identify the CCL22-CCR4 axis as an immune checkpoint that is crucial for the control of T cell immunity.


Assuntos
Células da Medula Óssea/imunologia , Comunicação Celular/imunologia , Quimiocina CCL22/imunologia , Células Dendríticas/imunologia , Linfonodos/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Quimiocina CCL22/genética , Células HEK293 , Humanos , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores CCR4/metabolismo , Transplante Homólogo
12.
Semin Immunopathol ; 40(4): 343-355, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29808388

RESUMO

Natural killer (NK) cells are classified as innate immune cells, given their ability to rapidly respond and kill transformed or virally infected cells without prior sensitization. Recently, accumulating evidence suggests that NK cells also exhibit many characteristics similar to cells of the adaptive immune system. Analogous to T cells, NK cells acquire self-tolerance during development, express antigen-specific receptors, undergo clonal-like expansion, and can become long-lived, self-renewing memory cells with potent effector function providing potent protection against reappearing pathogens. In this review, we discuss the requirements for memory NK cell generation and highlight the similarities with the formation of memory T cells.


Assuntos
Imunidade Inata , Memória Imunológica , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Animais , Antígenos/imunologia , Biomarcadores , Citocinas/metabolismo , Epitopos de Linfócito T/imunologia , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/imunologia , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Especificidade de Órgãos , Fenótipo , Transdução de Sinais
13.
Sci Immunol ; 2(18)2017 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-29222089

RESUMO

Natural killer (NK) cells are innate lymphocytes that have features of adaptive immunity such as clonal expansion and generation of long-lived memory. Interleukin-12 (IL-12) signaling through its downstream transcription factor signal transducer and activator of transcription 4 (STAT4) is required for the generation of memory NK cells after expansion. We identify gene loci that are highly enriched for STAT4 binding using chromatin immunoprecipitation sequencing for STAT4 and the permissive histone mark H3K4me3 in activated NK cells. We found that promoter regions of Runx1 and Runx3 are targets of STAT4 and that STAT4 binding during NK cell activation induces epigenetic modifications of Runx gene loci resulting in increased expression. Furthermore, specific ablation of Runx1, Runx3, or their binding partner Cbfb in NK cells resulted in defective clonal expansion and memory formation during viral infection, with evidence for Runx1-mediated control of a cell cycle program. Thus, our study reveals a mechanism whereby STAT4-mediated epigenetic control of individual Runx transcription factors promotes the adaptive behavior of antiviral NK cells.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Subunidade beta de Fator de Ligação ao Core/metabolismo , Células Matadoras Naturais/imunologia , Animais , Subunidade alfa 2 de Fator de Ligação ao Core/deficiência , Subunidade alfa 3 de Fator de Ligação ao Core/deficiência , Subunidade beta de Fator de Ligação ao Core/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT4/metabolismo
14.
Cell Rep ; 17(3): 636-644, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27732841

RESUMO

Despite robust secondary T cell expansion primed by vaccination, the impact on primary immune responses to heterotypic antigens remains undefined. Here we show that secondary expansion of epitope-specific memory CD8+ T cells primed by prior infection with recombinant pathogens limits the primary expansion of naive CD8+ T cells with specificity to new heterologous antigens, dampening protective immunity against subsequent pathogen challenge. The degree of naive T cell repression directly paralleled the magnitude of the recall response. Suppressed primary T cell priming reflects competition for antigen accessibility, since clonal expansion was not inhibited if the primary and secondary epitopes were expressed on different dendritic cells. Interestingly, robust recall responses did not impact antigen-specific NK cells, suggesting that adaptive and innate lymphocyte responses possess different activation requirements or occur in distinct anatomical locations. These findings have important implications in pathogen vaccination strategies that depend on the targeting of multiple T cell epitopes.


Assuntos
Epitopos de Linfócito T/imunologia , Muromegalovirus/fisiologia , Linfócitos T/imunologia , Vacinação , Animais , Células Apresentadoras de Antígenos/metabolismo , Antígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Células Clonais , Listeria/fisiologia , Camundongos , Recombinação Genética/genética
15.
J Exp Med ; 213(2): 225-33, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26755706

RESUMO

Type I interferon (IFN) is crucial in host antiviral defense. Previous studies have described the pleiotropic role of type I IFNs on innate and adaptive immune cells during viral infection. Here, we demonstrate that natural killer (NK) cells from mice lacking the type I IFN-α receptor (Ifnar(-/-)) or STAT1 (which signals downstream of IFNAR) are defective in expansion and memory cell formation after mouse cytomegalovirus (MCMV) infection. Despite comparable proliferation, Ifnar(-/-) NK cells showed diminished protection against MCMV infection and exhibited more apoptosis compared with wild-type NK cells. Furthermore, we show that Ifnar(-/-) NK cells express increased levels of NK group 2 member D (NKG2D) ligands during viral infection and are susceptible to NK cell-mediated fratricide in a perforin- and NKG2D-dependent manner. Adoptive transfer of Ifnar(-/-) NK cells into NK cell-deficient mice reverses the defect in survival and expansion. Our study reveals a novel type I IFN-dependent mechanism by which NK cells evade mechanisms of cell death after viral infection.


Assuntos
Infecções por Herpesviridae/imunologia , Interferon Tipo I/metabolismo , Células Matadoras Naturais/imunologia , Muromegalovirus , Animais , Apoptose , Proliferação de Células , Infecções por Herpesviridae/metabolismo , Infecções por Herpesviridae/patologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Perforina/deficiência , Perforina/genética , Perforina/metabolismo , Receptor de Interferon alfa e beta/deficiência , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/metabolismo , Fator de Transcrição STAT1/deficiência , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo
16.
Oncoimmunology ; 5(3): e1105428, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27195186

RESUMO

T cell infiltration at the tumor site has been identified as a major predictor for the efficacy of adoptive T cell therapy. The chemokine C-C motif ligand 22 (CCL22) is highly expressed by immune cells in murine and human pancreatic cancer. Expression of its corresponding receptor, C-C chemokine receptor type 4 (CCR4), is restricted to regulatory T cells (Treg). We show that transduction of cytotoxic T cells (CTL) with CCR4 enhances their immigration into a pancreatic cancer model. Further, we show that binding of CCR4 with CCL22 strengthens the binding of T cell LFA-1 to dendritic cell (DC) ICAM-1 and increases CTL activation. In vivo, in a model of subcutaneous pancreatic cancer, treatment of tumor-bearing mice with CCR4-transduced CTL led to the eradication of established tumors in 40% of the mice. In conclusion, CCR4 overexpression in CTL is a promising therapeutic strategy to enhance the efficacy of adoptive T cell transfer (ACT).

17.
Cell Rep ; 15(9): 1910-9, 2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27210760

RESUMO

Autophagy is an essential cellular survival mechanism that is required for adaptive lymphocyte development; however, its role in innate lymphoid cell (ILC) development remains unknown. Furthermore, the conditions that promote lymphocyte autophagy during homeostasis are poorly understood. Here, we demonstrate that Atg5, an essential component of the autophagy machinery, is required for the development of mature natural killer (NK) cells and group 1, 2, and 3 innate ILCs. Although inducible ablation of Atg5 was dispensable for the homeostasis of lymphocyte precursors and mature lymphocytes in lymphoreplete mice, we found that autophagy is induced in both adaptive and innate lymphocytes during homeostatic proliferation in lymphopenic hosts to promote their survival by limiting cell-intrinsic apoptosis. Induction of autophagy through metformin treatment following homeostatic proliferation increased lymphocyte numbers through an Atg5-dependent mechanism. These findings highlight the essential role for autophagy in ILC development and lymphocyte survival during lymphopenia.


Assuntos
Proteína 5 Relacionada à Autofagia/metabolismo , Imunidade Inata , Linfócitos/citologia , Animais , Autofagia , Proliferação de Células , Sobrevivência Celular , Homeostase , Linfopenia/imunologia , Linfopenia/patologia , Metformina/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
18.
Oncoimmunology ; 5(9): e1175794, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27757295

RESUMO

In cancer patients, immunosuppression through regulatory T cells (Treg) is a crucial component of tumor immune evasion and contributes to disease progression. Tumor-infiltrating Treg in particular suppress local effector T cell responses and are associated with poor prognosis in tumors such as human pancreatic cancer or hepatocellular carcinoma (HCC). The chemokine CCL22 is known to recruit Treg into the tumor tissue and many types of human tumors are known to express high levels of CCL22. The mechanisms leading to intratumoral secretion of CCL22 are so far unknown. We demonstrate here that intratumoral CCL22 is induced in tumor-infiltrating immune cells through cancer cell-derived interleukin-1 (IL-1α). In pancreatic cancer and HCC, CCL22 is produced by intratumoral dendritic cells, while the cancer cells themselves do not secrete CCL22 in vitro and in vivo. Incubation of human peripheral blood mononuclear cells (PBMC) or murine splenocytes with tumor cells or tumor cell supernatants strongly induced CCL22 secretion in vitro. Tumor cell supernatants contained IL-1 and CCL22 induction in PBMC could be specifically prevented by the IL-1 receptor antagonist anakinra or by transfection of tumor cell lines with IL-1 siRNA, leading to a suppression of Treg migration. In conclusion, we identify here tumor cell-derived IL-1α as a major inducer of the Treg attracting chemokine CCL22 in human cancer cells. Therapeutic blockade of the IL-1 pathway could represent a promising strategy to inhibit tumor-induced immunosuppression.

19.
Am J Reprod Immunol ; 74(3): 216-27, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25922986

RESUMO

PROBLEM: Regulatory T cells (Treg) are a T-cell subpopulation with suppressive capacities, specifically attracted by CCL22. We aimed to investigate whether CCL22 is expressed in human placentas and whether its presence, together with Treg infiltration, is associated with miscarriage conditions. METHOD OF STUDY: Paraffin samples were stained for CCL22 and for the Treg-specific transcription factor FoxP3. Expression levels were evaluated in a semi-quantitative manner. Double immunofluorescence was used for the identification of CCL22-producing cells. RESULTS: In all placentas, trophoblasts expressed CCL22. Interestingly, expression in the decidua was only observed in miscarriage conditions. Maternal stromal cells expressed CCL22. Correlation with a higher presence of Treg in the decidua of abortive tissues was observed. CONCLUSION: Our results demonstrate that CCL22 is expressed in human placenta. Decidual expression was only observed in miscarriage conditions and correlates with Treg infiltration. Thus, CCL22 plays a role in human pregnancy and may occur as a negative feedback response to pro-inflammatory events during miscarriage conditions.


Assuntos
Aborto Espontâneo/metabolismo , Quimiocina CCL22/metabolismo , Decídua/metabolismo , Placenta/metabolismo , Linfócitos T Reguladores/metabolismo , Aborto Espontâneo/imunologia , Adolescente , Adulto , Decídua/imunologia , Feminino , Humanos , Placenta/imunologia , Gravidez , Linfócitos T Reguladores/imunologia , Adulto Jovem
20.
J Natl Cancer Inst ; 107(8)2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26105028

RESUMO

BACKGROUND: Adoptive T cell transfer (ACT) is currently under investigation for the treatment of metastatic cancer. Recent evidence suggests that the coinhibitory PD-1-PD-L1 axis plays a major role in ACT failure. We hypothesized that a new fusion receptor reverting PD-1-mediated inhibition into CD28 costimulation may break peripheral tolerance. METHODS: Different PD-1-CD28 fusion receptor constructs were created and retrovirally transduced into primary T cell receptor transgenic murine CD8(+) T cells specific for ovalbumin (OT-1). Cytokine release, proliferation, cytotoxicity, and tumor recognition were analyzed in vitro. Antitumor efficacy and mode of action were investigated in mice bearing subcutaneous tumors induced with the pancreatic carcinoma cell line Panc02 expressing the model antigen ovalbumin (Panc-OVA). For antitumoral efficacy, six to eight mice per group were used. All statistical tests are two-sided. RESULTS: Transduction of the PD-1-CD28 receptor constructs mediated enhanced cytokine release, T cell proliferation, and T cell-induced lysis of target tumor cells. The PD-1-CD28 receptor function was dependent on two of the CD28-signaling motifs and IFN-γ release. Treatment of mice with established Panc-OVA tumors with fusion receptor-transduced OT-1 T cells mediated complete tumor regression. Mice rejecting the tumor were protected upon subsequent rechallenge with either ovalbumin-positive or -negative tumors, indicative of a memory response and epitope spreading in nine of 11 mice vs none of the six naïve mice (P < .001). Treatment efficacy was associated with accumulation of IFN-γ-producing T cells and an increased ratio of CD8(+) T cells to immunosuppressive myeloid-derived suppressor cells in the tumors. CONCLUSIONS: Transduction of T cells with this new PD-1-CD28 receptor has the potential of breaking the PD-1-PD-L1-immunosuppressive axis in ACT.


Assuntos
Transferência Adotiva/métodos , Antígeno B7-H1/imunologia , Antígenos CD28/imunologia , Linfócitos T CD8-Positivos/imunologia , Terapia de Imunossupressão , Interferon gama/metabolismo , Ovalbumina/imunologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/terapia , Receptor de Morte Celular Programada 1/imunologia , Animais , Linhagem Celular Tumoral , Epitopos , Contagem de Linfócitos , Camundongos , Camundongos Transgênicos , Transdução de Sinais/imunologia , Transdução Genética , Resultado do Tratamento
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