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1.
Nat Immunol ; 20(9): 1110-1128, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31406380

RESUMO

In recent years, a population of unconventional T cells called 'mucosal-associated invariant T cells' (MAIT cells) has captured the attention of immunologists and clinicians due to their abundance in humans, their involvement in a broad range of infectious and non-infectious diseases and their unusual specificity for microbial riboflavin-derivative antigens presented by the major histocompatibility complex (MHC) class I-like protein MR1. MAIT cells use a limited T cell antigen receptor (TCR) repertoire with public antigen specificities that are conserved across species. They can be activated by TCR-dependent and TCR-independent mechanisms and exhibit rapid, innate-like effector responses. Here we review evidence showing that MAIT cells are a key component of the immune system and discuss their basic biology, development, role in disease and immunotherapeutic potential.


Assuntos
Apresentação do Antígeno/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Menor/imunologia , Células T Invariáveis Associadas à Mucosa/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Antígenos/imunologia , Suscetibilidade a Doenças/imunologia , Humanos , Ativação Linfocitária/imunologia , Camundongos , Neoplasias/imunologia
2.
Braz J Infect Dis ; 23(3): 151-159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31271732

RESUMO

BACKGROUND: HIV infection harms adaptive cellular immunity mechanisms. Long-term virological control by combined antiretroviral therapy (cART) reduces the risk of mycobacterial infections. Thus, we aimed to study cellular responses to mycobacterial antigens in 20 HIV-infected adolescents with at least one year of virological control (HIV-RNA <40 copies/mL) and 20 healthy adolescents. METHODS: We evaluated CD8 and γδ T-cell degranulation by measurement of CD107a membrane expression after stimulation with lysates from BCG (10 µg/mL) and H37RA Mycobacterium tuberculosis (Mtb, 10 µg/mL). Immune activation and antigen-presenting ability were also assessed by determination of HLA-DR, CD80, and CD86 markers. RESULTS: TCR γδ T-cell CD107a expression was similar between groups in response to mycobacterial antigens, and lower in the HIV-infected group in response to mitogen. Higher baseline HLA-DR expression and lower mycobacterial-stimulated expression was found within the HIV-infected group. CONCLUSIONS: Similar degranulation in stimulated CD8+ and TCR γδ T-cells from HIV-infected adolescents, when compared to healthy controls suggests long-term immunological preservation with immune reconstitution under successful cART. However, differences in HLA-DR expression may represent ongoing inflammation and lower specific responses in HIV-infected youth. These features may be relevant in the context of the precocity and severity of vertically acquired HIV infection.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/imunologia , Fármacos Anti-HIV/uso terapêutico , Antígenos de Bactérias/imunologia , Linfócitos T CD8-Positivos/imunologia , Mycobacterium tuberculosis/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Tuberculose/imunologia , Apresentação do Antígeno/imunologia , Antígenos de Bactérias/efeitos dos fármacos , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Imunofenotipagem , Transmissão Vertical de Doença Infecciosa , Masculino , Estudos Prospectivos , Adulto Jovem
3.
Nature ; 571(7766): 565-569, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31316206

RESUMO

Parkinson's disease is a neurodegenerative disorder with motor symptoms linked to the loss of dopaminergic neurons in the substantia nigra compacta. Although the mechanisms that trigger the loss of dopaminergic neurons are unclear, mitochondrial dysfunction and inflammation are thought to have key roles1,2. An early-onset form of Parkinson's disease is associated with mutations in the PINK1 kinase and PRKN ubiquitin ligase genes3. PINK1 and Parkin (encoded by PRKN) are involved in the clearance of damaged mitochondria in cultured cells4, but recent evidence obtained using knockout and knockin mouse models have led to contradictory results regarding the contributions of PINK1 and Parkin to mitophagy in vivo5-8. It has previously been shown that PINK1 and Parkin have a key role in adaptive immunity by repressing presentation of mitochondrial antigens9, which suggests that autoimmune mechanisms participate in the aetiology of Parkinson's disease. Here we show that intestinal infection with Gram-negative bacteria in Pink1-/- mice engages mitochondrial antigen presentation and autoimmune mechanisms that elicit the establishment of cytotoxic mitochondria-specific CD8+ T cells in the periphery and in the brain. Notably, these mice show a sharp decrease in the density of dopaminergic axonal varicosities in the striatum and are affected by motor impairment that is reversed after treatment with L-DOPA. These data support the idea that PINK1 is a repressor of the immune system, and provide a pathophysiological model in which intestinal infection acts as a triggering event in Parkinson's disease, which highlights the relevance of the gut-brain axis in the disease10.


Assuntos
Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/fisiopatologia , Intestinos/microbiologia , Doença de Parkinson/genética , Doença de Parkinson/microbiologia , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Animais , Apresentação do Antígeno/imunologia , Autoantígenos/imunologia , Axônios/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Citrobacter rodentium/imunologia , Citrobacter rodentium/patogenicidade , Modelos Animais de Doenças , Neurônios Dopaminérgicos/imunologia , Neurônios Dopaminérgicos/patologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/patologia , Feminino , Intestinos/imunologia , Intestinos/patologia , Levodopa/uso terapêutico , Masculino , Camundongos , Mitocôndrias/imunologia , Mitocôndrias/patologia , Neostriado/imunologia , Neostriado/microbiologia , Neostriado/patologia , Neostriado/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Proteínas Quinases/imunologia , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia
4.
Nat Immunol ; 20(8): 963-969, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285625

RESUMO

Over the past several decades, B cell antigen receptor (BCR)-induced signaling pathways have been described in extraordinary molecular detail, mainly from studies of B cell responses to antigens in vitro. BCR signaling has been shown to govern the initiation of transcriptional programs associated with B cell activation and fate decisions, as well as the BCR-dependent processing of antigen and presentation of antigen to T cells. However, although the potential of the BCR to orchestrate B cell behavior was known, there was no clear appreciation of the context in which B cells signal in secondary lymphoid organs in vivo or how that context influences signaling. In this Review, we describe the current view of the cellular consequences of BCR signaling and advances in the understanding of B cell signaling in context in vivo.


Assuntos
Apresentação do Antígeno/imunologia , Antígenos/imunologia , Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Humanos , Ativação Linfocitária/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia
5.
Mol Immunol ; 112: 274-282, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31226552

RESUMO

The viral peptides presentation by major histocompatibility complex class I (MHC I) molecules play a pivotal role in T-cell recognition and the subsequent virus clearance. This process is delicately adjusted by the variant residues of MHC I, especially the residues in the peptide binding groove (PBG). In a series of MHC I molecules, a salt bridge is formed above the N-terminus of the peptides. However, the potential impact of the salt bridge on peptide binding and T-cell receptor (TCR) recognition of MHC I, as well as the corresponding molecular basis, are still largely unknown. Herein, we determined the structures of HLA-B*4001 and H-2Kd in which two different types of salt bridges (Arg62-Glu163 or Arg66-Glu163) across the PBG were observed. Although the two salt bridges led to different conformation shifts of both the MHC I α helix and the peptides, binding of the peptides with the salt bridge residues was relatively conserved. Furthermore, through a series of in vitro and in vivo investigations, we found that MHC I mutations that disrupt the salt bridge alleviate peptide binding and can weaken the TCR recognition of MHC I-peptide complexes. Our study may provide key references for understanding MHC I-restricted peptide recognition by T-cells.


Assuntos
Apresentação do Antígeno/imunologia , Genes MHC Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Peptídeos/imunologia , Ligação Proteica/imunologia , Linfócitos T/imunologia , Animais , Sítios de Ligação/imunologia , Feminino , Antígenos HLA-B/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Conformação Proteica , Receptores de Antígenos de Linfócitos T/imunologia
6.
Nat Commun ; 10(1): 2678, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31213601

RESUMO

Myeloid cells contribute to tumor progression, but how the constellation of receptors they express regulates their functions within the tumor microenvironment (TME) is unclear. We demonstrate that Fcmr (Toso), the putative receptor for soluble IgM, modulates myeloid cell responses to cancer. In a syngeneic melanoma model, Fcmr ablation in myeloid cells suppressed tumor growth and extended mouse survival. Fcmr deficiency increased myeloid cell population density in this malignancy and enhanced anti-tumor immunity. Single-cell RNA sequencing of Fcmr-deficient tumor-associated mononuclear phagocytes revealed a unique subset with enhanced antigen processing/presenting properties. Conversely, Fcmr activity negatively regulated the activation and migratory capacity of myeloid cells in vivo, and T cell activation by bone marrow-derived dendritic cells in vitro. Therapeutic targeting of Fcmr during oncogenesis decreased tumor growth when used as a single agent or in combination with anti-PD-1. Thus, Fcmr regulates myeloid cell activation within the TME and may be a potential therapeutic target.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas de Transporte/metabolismo , Melanoma Experimental/imunologia , Proteínas de Membrana/metabolismo , Monócitos/imunologia , Neoplasias Cutâneas/imunologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Apresentação do Antígeno/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinogênese/efeitos dos fármacos , Carcinogênese/imunologia , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Linhagem Celular Tumoral/transplante , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Feminino , Ativação Linfocitária/imunologia , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/mortalidade , Melanoma Experimental/patologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Análise de Sobrevida , Linfócitos T/imunologia , Microambiente Tumoral/imunologia
7.
Nat Immunol ; 20(7): 835-851, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31160797

RESUMO

How tumor cells genetically lose antigenicity and evade immune checkpoints remains largely elusive. We report that tissue-specific expression of the human long noncoding RNA LINK-A in mouse mammary glands initiates metastatic mammary gland tumors, which phenotypically resemble human triple-negative breast cancer (TNBC). LINK-A expression facilitated crosstalk between phosphatidylinositol-(3,4,5)-trisphosphate and inhibitory G-protein-coupled receptor (GPCR) pathways, attenuating protein kinase A-mediated phosphorylation of the E3 ubiquitin ligase TRIM71. Consequently, LINK-A expression enhanced K48-polyubiquitination-mediated degradation of the antigen peptide-loading complex (PLC) and intrinsic tumor suppressors Rb and p53. Treatment with LINK-A locked nucleic acids or GPCR antagonists stabilized the PLC components, Rb and p53, and sensitized mammary gland tumors to immune checkpoint blockers. Patients with programmed ccll death protein-1(PD-1) blockade-resistant TNBC exhibited elevated LINK-A levels and downregulated PLC components. Hence we demonstrate lncRNA-dependent downregulation of antigenicity and intrinsic tumor suppression, which provides the basis for developing combinational immunotherapy treatment regimens and early TNBC prevention.


Assuntos
Apresentação do Antígeno/imunologia , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Neoplasias/imunologia , Oncogenes , RNA Longo não Codificante/genética , Evasão Tumoral/genética , Evasão Tumoral/imunologia , Adenoma/genética , Adenoma/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Humanos , Camundongos , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nat Commun ; 10(1): 2759, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227717

RESUMO

Langerhans cells (LC) are thought to be the only mononuclear phagocyte population in the epidermis where they detect pathogens. Here, we show that CD11c+ dendritic cells (DCs) are also present. These cells are transcriptionally similar to dermal cDC2 but are more efficient antigen-presenting cells. Compared to LCs, epidermal CD11c+ DCs are enriched in anogenital tissues where they preferentially interact with HIV, express the higher levels of HIV entry receptor CCR5, support the higher levels of HIV uptake and replication and are more efficient at transmitting the virus to CD4 T cells. Importantly, these findings are observed using both a lab-adapted and transmitted/founder strain of HIV. We also describe a CD33low cell population, which is transcriptionally similar to LCs but does not appear to function as antigen-presenting cells or acts as HIV target cells. Our findings reveal that epidermal DCs in anogenital tissues potentially play a key role in sexual transmission of HIV.


Assuntos
Células Dendríticas/virologia , Células Epidérmicas/virologia , Infecções por HIV/transmissão , HIV-1/imunologia , Apresentação do Antígeno/imunologia , Antígeno CD11c/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Epidérmicas/imunologia , Células Epidérmicas/metabolismo , Epiderme/imunologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Voluntários Saudáveis , Humanos , Masculino , Cultura Primária de Células , Receptores CCR5/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Linfócitos T/imunologia , Internalização do Vírus
9.
Immunity ; 50(5): 1188-1201.e6, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31053504

RESUMO

Lymph nodes (LNs) play critical roles in adaptive immunity by concentrating in one location the antigens, antigen-presenting cells, and antigen-responsive lymphocytes involved in such responses. Recent studies have revealed nonrandom localization of innate and adaptive immune cells within these organs, suggesting that microanatomical positioning optimizes responses involving sparse cooperating cells. Here, we report that the peripheral localization of LN cDC2 dendritic cells specialized for MHC-II antigen presentation is matched by a similarly biased paracortical distribution of CD4+ T cells directed by the chemoattractant receptor Ebi2. In the absence of Ebi2, CD4+ T cells lose their location bias and are delayed in antigen recognition, proliferative expansion, differentiation, direct effector activity, and provision of help for CD8+ T cell-mediated memory responses, limiting host defense and vaccine responses. These findings demonstrate evolutionary selection for distinct niches within the LN that promote cellular responses, emphasizing the critical link between fine-grained tissue organization and host defense.


Assuntos
Imunidade Adaptativa/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Apresentação do Antígeno/imunologia , Antígenos/imunologia , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas-G/genética
10.
Am Soc Clin Oncol Educ Book ; 39: 147-164, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31099674

RESUMO

The emergence of immune checkpoint blockade therapies over the last decade has transformed cancer treatment in a wide range of tumor types. Unprecedented and durable clinical responses in difficult-to-treat cancer histologies have been observed. However, despite these promising long-term responses, the majority of patients fail to respond to immune checkpoint blockade, demonstrating primary resistance. Additionally, many of those who initially respond to treatment eventually experience relapse secondary to acquired resistance. Both primary and acquired resistance are a result of complex and constantly evolving interactions between cancer cells and the immune system. Many mechanisms of resistance have been characterized to date, and more continue to be uncovered. By elucidating and targeting mechanisms of resistance, treatments can be tailored to improve clinical outcomes. This review will discuss the landscape of immune checkpoint blockade response data, different resistance mechanisms, and potential therapeutic strategies to overcome resistance.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Apresentação do Antígeno/imunologia , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Biomarcadores Tumorais , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Microbioma Gastrointestinal , Humanos , Imunidade , Imunoterapia , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neoplasias/diagnóstico , Neoplasias/imunologia , Transdução de Sinais , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microambiente Tumoral/imunologia
11.
Nat Commun ; 10(1): 2243, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113973

RESUMO

Mucosal-associated invariant T (MAIT) cells express an invariant TRAV1/TRAJ33 TCR-α chain and are restricted to the MHC-I-like molecule, MR1. Whether MAIT cell development depends on this invariant TCR-α chain is unclear. Here we generate Traj33-deficient mice and show that they are highly depleted of MAIT cells; however, a residual population remains and can respond to exogenous antigen in vitro or pulmonary Legionella challenge in vivo. These residual cells include some that express Trav1+ TCRs with conservative Traj-gene substitutions, and others that express Trav1- TCRs with a broad range of Traj genes. We further report that human TRAV1-2- MR1-restricted T cells contain both MAIT-like and non-MAIT-like cells, as judged by their TCR repertoire, antigen reactivity and phenotypic features. These include a MAIT-like population that expresses a public, canonical TRAV36+ TRBV28+ TCR. Our findings highlight the TCR diversity and the resulting potential impact on antigen recognition by MR1-restricted T cells.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Legionelose/imunologia , Antígenos de Histocompatibilidade Menor/metabolismo , Células T Invariáveis Associadas à Mucosa/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Animais , Apresentação do Antígeno/imunologia , Modelos Animais de Doenças , Células HEK293 , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Legionella/imunologia , Legionelose/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/imunologia , Células T Invariáveis Associadas à Mucosa/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia
12.
Nat Commun ; 10(1): 2220, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101805

RESUMO

Both medullary thymic epithelial cells (mTEC) and dendritic cells (DC) present tissue-restricted antigens (TRA) to thymocytes to induce central tolerance, but the relative contributions of these antigen-presenting cell (APC) subsets remain unresolved. Here we developed a two-photon microscopy approach to observe thymocytes interacting with intact APCs presenting TRAs. We find that mTECs and DCs cooperate extensively to induce tolerance, with their relative contributions regulated by the cellular form of the TRA and the class of major histocompatibility complex (MHC) on which antigen is presented. Even when TRA expression is restricted to mTECs, DCs still present self-antigens at least as frequently as mTECs. Notably, the DC subset cDC2 efficiently acquires secreted mTEC-derived TRAs for cross-presentation on MHC-I. By directly imaging interactions between thymocytes and APCs, while monitoring intracellular signaling, this study reveals that distinct DC subsets and AIRE+ mTECs contribute substantially to presentation of diverse self-antigens for establishing central tolerance.


Assuntos
Tolerância Central/imunologia , Células Dendríticas/imunologia , Timócitos/imunologia , Timo/imunologia , Animais , Apresentação do Antígeno/imunologia , Autoantígenos/imunologia , Autoantígenos/metabolismo , Transplante de Medula Óssea , Separação Celular/métodos , Células Dendríticas/metabolismo , Células Epiteliais/imunologia , Feminino , Citometria de Fluxo/métodos , Microscopia Intravital/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Linfócitos T Reguladores/imunologia , Timócitos/metabolismo , Timo/citologia , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo , Quimeras de Transplante/imunologia
13.
PLoS Pathog ; 15(4): e1007711, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31034515

RESUMO

The human specific poxvirus molluscum contagiosum virus (MCV) produces skin lesions that can persist with minimal inflammation, suggesting that the virus has developed robust immune evasion strategies. However, investigations into the underlying mechanisms of MCV pathogenesis have been hindered by the lack of a model system to propagate the virus. Herein we demonstrate that MCV-encoded MC80 can disrupt MHC-I antigen presentation in human and mouse cells. MC80 shares moderate sequence-similarity with MHC-I and we find that it associates with components of the peptide-loading complex. Expression of MC80 results in ER-retention of host MHC-I and thereby reduced cell surface presentation. MC80 accomplishes this by engaging tapasin via its luminal domain, targeting it for ubiquitination and ER-associated degradation in a process dependent on the MC80 transmembrane region and cytoplasmic tail. Tapasin degradation is accompanied by a loss of TAP, which limits MHC-I access to cytosolic peptides. Our findings reveal a unique mechanism by which MCV undermines adaptive immune surveillance.


Assuntos
Apresentação do Antígeno/imunologia , Degradação Associada com o Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Proteínas de Membrana Transportadoras/metabolismo , Molusco Contagioso/imunologia , Vírus do Molusco Contagioso/imunologia , Proteínas Virais/metabolismo , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Células Cultivadas , Humanos , Evasão da Resposta Imune , Camundongos , Molusco Contagioso/metabolismo , Molusco Contagioso/virologia , Linfócitos T Citotóxicos/imunologia , Proteínas Virais/genética
14.
Nat Commun ; 10(1): 1772, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992440

RESUMO

Deep understanding of the genomic and immunological differences between Chinese and Western lung cancer patients is of great importance for target therapy selection and development for Chinese patients. Here we report an extensive molecular and immune profiling study of 245 Chinese patients with non-small cell lung cancer. Tumor-infiltrating lymphocyte estimated using immune cell signatures is found to be significantly higher in adenocarcinoma (ADC, 72.5%) compared with squamous cell carcinoma (SQCC, 54.4%). The correlation of genomic alterations with immune signatures reveals that low immune infiltration was associated with EGFR mutations in ADC samples, PI3K and/or WNT pathway activation in SQCC. While KRAS mutations are found to be significantly associated with T cell infiltration in ADC samples. The SQCC patients with high antigen presentation machinery and cytotoxic T cell signature scores are found to have a prolonged overall survival time.


Assuntos
Adenocarcinoma de Pulmão/genética , Grupo com Ancestrais do Continente Asiático/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/genética , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/mortalidade , Idoso , Apresentação do Antígeno/genética , Apresentação do Antígeno/imunologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/mortalidade , Conjuntos de Dados como Assunto , Receptores ErbB/genética , Feminino , Genômica , Humanos , Neoplasias Pulmonares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Linfócitos T Citotóxicos/imunologia , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/imunologia
15.
Int J Nanomedicine ; 14: 2069-2089, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30988609

RESUMO

Purpose: Melanoma is the most aggressive form of skin cancer. Chemotherapy at a late stage fails due to low accumulation in tumors, indicating the need for targeted therapy. Materials and methods: To increase drug uptake by tumor cells, we have targeted doxorubicin-containing liposomes using a T-cell receptor (TCR)-like antibody (scFv G8 and Hyb3) directed against melanoma antigen A1 (MAGE-A1) presented by human leukocyte antigen A1 (M1/A1). With the use of flow cytometry and confocal microscopy, we have tested our formulation in vitro. In vivo pharmacokinetics was done in tumor-free nu/nu mice, while biodistribution and efficacy study was done in nu/nu mice xenograft. Results: We demonstrated two to five times higher binding and internalization of these immunoliposomes by M1+/A1+ melanoma cells in vitro in comparison with nontargeted liposomes. Cytotoxicity assay showed significant tumor cell kill at 10 µM doxorubicin (DXR) for targeted vs nontargeted liposomes. In vivo pharmacokinetics of nontargeted and targeted liposomes were similar, while accumulation of targeted liposomes was 2- to 2.5-fold and 6.6-fold enhanced when compared with nontargeted liposomes and free drug, respectively. Notably, we showed a superior antitumor activity of MAGE-A1-targeted DXR liposomes toward M1+/A1+ expressing tumors in mice compared with the treatment of M1-/A1+ tumors. Our results indicate that targeted liposomes showed better cytotoxicity in vitro and pharmacokinetics in vivo. Conclusion: Liposomes decorated with TCR-mimicking scFv antibodies effectively and selectively target antigen-positive melanoma. We showed that DXR-loaded liposomes coupled to anti-M1/-A1 scFv inflict a significant antitumor response. Targeting tumor cells specifically promotes internalization of drug-containing nanoparticles and may improve drug delivery and ultimately antitumor efficacy. Our data argue that targeting MAGE in A1 context, by nanosized carriers decorated with TCR-like antibodies mimicking scFv, can be used as a theragnostic platform for drug delivery, immunotherapy, and potentially imaging, and diagnosis of melanoma.


Assuntos
Apresentação do Antígeno/imunologia , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Antígeno HLA-A1/imunologia , Lipossomos/administração & dosagem , Melanoma/tratamento farmacológico , Nanopartículas/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/química , Doxorrubicina/farmacocinética , Humanos , Lipossomos/química , Lipossomos/imunologia , Melanoma/imunologia , Camundongos Nus , Nanopartículas/química , Receptores de Antígenos de Linfócitos T/imunologia , Anticorpos de Cadeia Única/imunologia , Distribuição Tecidual , Células Tumorais Cultivadas
16.
PLoS Pathog ; 15(3): e1007595, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30845208

RESUMO

Despite a broad cell-type tropism, cytomegalovirus (CMV) is an evidentially pulmonary pathogen. Predilection for the lungs is of medical relevance in immunocompromised recipients of hematopoietic cell transplantation, in whom interstitial CMV pneumonia is a frequent and, if left untreated, fatal clinical manifestation of human CMV infection. A conceivable contribution of CMV to airway diseases of other etiology is an issue that so far attracted little medical attention. As the route of primary CMV infection upon host-to-host transmission in early childhood involves airway mucosa, coincidence of CMV airway infection and exposure to airborne environmental antigens is almost unavoidable. For investigating possible consequences of such a coincidence, we established a mouse model of airway co-exposure to CMV and ovalbumin (OVA) representing a protein antigen of an inherently low allergenic potential. Accordingly, intratracheal OVA exposure alone failed to sensitize for allergic airway disease (AAD) upon OVA aerosol challenge. In contrast, airway infection at the time of OVA sensitization predisposed for AAD that was characterized by airway inflammation, IgE secretion, thickening of airway epithelia, and goblet cell hyperplasia. This AAD histopathology was associated with a T helper type 2 (Th2) transcription profile in the lungs, including IL-4, IL-5, IL-9, and IL-25, known inducers of Th2-driven AAD. These symptoms were all prevented by a pre-challenge depletion of CD4+ T cells, but not of CD8+ T cells. As to the underlying mechanism, murine CMV activated migratory CD11b+ as well as CD103+ conventional dendritic cells (cDCs), which have been associated with Th2 cytokine-driven AAD and with antigen cross-presentation, respectively. This resulted in an enhanced OVA uptake and recruitment of the OVA-laden cDCs selectively to the draining tracheal lymph nodes for antigen presentation. We thus propose that CMV, through activation of migratory cDCs in the airway mucosa, can enhance the allergenic potential of otherwise poorly allergenic environmental protein antigens.


Assuntos
Alérgenos/metabolismo , Citomegalovirus/metabolismo , Células Dendríticas/imunologia , Alérgenos/efeitos adversos , Animais , Apresentação do Antígeno/imunologia , Antígenos CD11/imunologia , Citomegalovirus/patogenicidade , Células Dendríticas/microbiologia , Modelos Animais de Doenças , Feminino , Hipersensibilidade , Inflamação , Pulmão/fisiopatologia , Pulmão/virologia , Pneumopatias/etiologia , Pneumopatias/virologia , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina , Células Th2 , Ativação Viral/imunologia
17.
Nature ; 567(7749): 479-485, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30894752

RESUMO

The interplay between an evolving cancer and a dynamic immune microenvironment remains unclear. Here we analyse 258 regions from 88 early-stage, untreated non-small-cell lung cancers using RNA sequencing and histopathology-assessed tumour-infiltrating lymphocyte estimates. Immune infiltration varied both between and within tumours, with different mechanisms of neoantigen presentation dysfunction enriched in distinct immune microenvironments. Sparsely infiltrated tumours exhibited a waning of neoantigen editing during tumour evolution, indicative of historical immune editing, or copy-number loss of previously clonal neoantigens. Immune-infiltrated tumour regions exhibited ongoing immunoediting, with either loss of heterozygosity in human leukocyte antigens or depletion of expressed neoantigens. We identified promoter hypermethylation of genes that contain neoantigenic mutations as an epigenetic mechanism of immunoediting. Our results suggest that the immune microenvironment exerts a strong selection pressure in early-stage, untreated non-small-cell lung cancers that produces multiple routes to immune evasion, which are clinically relevant and forecast poor disease-free survival.


Assuntos
Antígenos de Neoplasias/imunologia , Evolução Molecular , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Evasão Tumoral/imunologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Apresentação do Antígeno/imunologia , Antígenos de Neoplasias/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/genética , Linfócitos do Interstício Tumoral/imunologia , Masculino , Prognóstico , Microambiente Tumoral/imunologia
18.
Diabetes ; 68(5): 988-1001, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30833470

RESUMO

Type 1 diabetes studies consistently generate data showing islet ß-cell dysfunction and T cell-mediated anti-ß-cell-specific autoimmunity. To explore the pathogenesis, we interrogated the ß-cell transcriptomes from donors with and without type 1 diabetes using both bulk-sorted and single ß-cells. Consistent with immunohistological studies, ß-cells from donors with type 1 diabetes displayed increased Class I transcripts and associated mRNA species. These ß-cells also expressed mRNA for Class II and Class II antigen presentation pathway components, but lacked the macrophage marker CD68. Immunohistological study of three independent cohorts of donors with recent-onset type 1 diabetes showed Class II protein and its transcriptional regulator Class II MHC trans-activator protein expressed by a subset of insulin+CD68- ß-cells, specifically found in islets with lymphocytic infiltrates. ß-Cell surface expression of HLA Class II was detected on a portion of CD45-insulin+ ß-cells from donors with type 1 diabetes by immunofluorescence and flow cytometry. Our data demonstrate that pancreatic ß-cells from donors with type 1 diabetes express Class II molecules on selected cells with other key genes in those pathways and inflammation-associated genes. ß-Cell expression of Class II molecules suggests that ß-cells may interact directly with islet-infiltrating CD4+ T cells and may play an immunopathogenic role.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Apresentação do Antígeno/imunologia , Autoimunidade/fisiologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Humanos , Insulina/metabolismo
19.
Hum Immunol ; 80(5): 302-309, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30817945

RESUMO

Autoimmune and autoinflammatory diseases affect millions worldwide. These classes of disease involve abnormal immune activation of both the innate and adaptive immune systems. While both classes of disease represent a spectrum of aberrant immune activation, excessive activation of the innate immune system has been considered causal for the inflammation and tissue damage found in autoinflammatory diseases, while excessive activation of the adaptive immune system has been thought to primarily contribute to end-organ symptoms noted in autoimmune diseases. Interestingly, the endoplasmic reticulum aminopeptidase 1 (ERAP1) protein, well known for its aminopeptidase function as a "molecular ruler", trimming peptides prior to their loading onto MHC-I molecules for antigen presentation in the ER, has also been shown to be genetically associated with both autoinflammatory and autoimmune diseases. Indeed, this multifaceted protein has been found to have many functions that affect both the innate and adaptive immune responses. In this review, we summarize these findings, with an attempt to identify the possible ERAP1 dependent mechanisms responsible for the pathogenesis of multiple, ERAP1 associated diseases.


Assuntos
Aminopeptidases/genética , Aminopeptidases/metabolismo , Doenças Autoimunes/etiologia , Doenças Autoimunes/metabolismo , Autoimunidade , Inflamação/etiologia , Inflamação/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Imunidade Adaptativa , Aminopeptidases/química , Animais , Apresentação do Antígeno/imunologia , Suscetibilidade a Doenças , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imunidade Inata , Antígenos de Histocompatibilidade Menor/química
20.
Hum Immunol ; 80(5): 318-324, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30825518

RESUMO

The endoplasmic reticulum (ER) aminopeptidases ERAP1 and ERAP2 are two multifunctional enzymes playing an important role in the biological processes requiring trimming of substrates, including the generation of major histocompatibility complex (MHC) class I binding peptides. In the absence of ERAP enzymes, the cells exhibit a different pool of peptides on their surface which can promote both NK and CD8+ T cell-mediated immune responses. The expression of ERAP1 and ERAP2 is frequently altered in tumors, as compared to their normal counterparts, but how this affects tumor growth and anti-tumor immune responses has been little investigated. This review will provide an overview of current knowledge on transcriptional and post-transcriptional regulations of ERAP enzymes, and will discuss the contribution of recent studies to our understanding of ERAP1 and ERAP2 role in cancer immunity.


Assuntos
Aminopeptidases/genética , Aminopeptidases/metabolismo , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Animais , Apresentação do Antígeno/imunologia , Retículo Endoplasmático/metabolismo , Variação Genética , Genômica/métodos , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunoterapia , Neoplasias/imunologia , Neoplasias/terapia , Ligação Proteica , Transcrição Genética
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