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1.
Sci Rep ; 11(1): 5402, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686135

RESUMO

Most multiple sclerosis (MS) patients given currently available disease-modifying drugs (DMDs) experience progressive disability. Accordingly, there is a need for new treatments that can limit the generation of new waves T cell autoreactivity that drive disease progression. Notably, immune cells express GABAA-receptors (GABAA-Rs) whose activation has anti-inflammatory effects such that GABA administration can ameliorate disease in models of type 1 diabetes, rheumatoid arthritis, and COVID-19. Here, we show that oral GABA, which cannot cross the blood-brain barrier (BBB), does not affect the course of murine experimental autoimmune encephalomyelitis (EAE). In contrast, oral administration of the BBB-permeable GABAA-R-specific agonist homotaurine ameliorates monophasic EAE, as well as advanced-stage relapsing-remitting EAE (RR-EAE). Homotaurine treatment beginning after the first peak of paralysis reduced the spreading of Th17 and Th1 responses from the priming immunogen to a new myelin T cell epitope within the CNS. Antigen-presenting cells (APC) isolated from homotaurine-treated mice displayed an attenuated ability to promote autoantigen-specific T cell proliferation. The ability of homotaurine treatment to limit epitope spreading within the CNS, along with its safety record, makes it an excellent candidate to help treat MS and other inflammatory disorders of the CNS.


Assuntos
Sistema Nervoso Central/patologia , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Taurina/análogos & derivados , Animais , Apresentação do Antígeno/efeitos dos fármacos , Células Apresentadoras de Antígenos/efeitos dos fármacos , Células Apresentadoras de Antígenos/imunologia , Proliferação de Células/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/imunologia , Modelos Animais de Doenças , Progressão da Doença , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Camundongos Endogâmicos C57BL , Esclerose Múltipla/patologia , Proteína Proteolipídica de Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Recidiva , Baço/patologia , Linfócitos T/efeitos dos fármacos , Taurina/farmacologia , Ácido gama-Aminobutírico/farmacologia
2.
PLoS Pathog ; 17(1): e1009168, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33444400

RESUMO

There is a critical need for adjuvants that can safely elicit potent and durable T cell-based immunity to intracellular pathogens. Here, we report that parenteral vaccination with a carbomer-based adjuvant, Adjuplex (ADJ), stimulated robust CD8 T-cell responses to subunit antigens and afforded effective immunity against respiratory challenge with a virus and a systemic intracellular bacterial infection. Studies to understand the metabolic and molecular basis for ADJ's effect on antigen cross-presentation by dendritic cells (DCs) revealed several unique and distinctive mechanisms. ADJ-stimulated DCs produced IL-1ß and IL-18, suggestive of inflammasome activation, but in vivo activation of CD8 T cells was unaffected in caspase 1-deficient mice. Cross-presentation induced by TLR agonists requires a critical switch to anabolic metabolism, but ADJ enhanced cross presentation without this metabolic switch in DCs. Instead, ADJ induced in DCs, an unique metabolic state, typified by dampened oxidative phosphorylation and basal levels of glycolysis. In the absence of increased glycolytic flux, ADJ modulated multiple steps in the cytosolic pathway of cross-presentation by enabling accumulation of degraded antigen, reducing endosomal acidity and promoting antigen localization to early endosomes. Further, by increasing ROS production and lipid peroxidation, ADJ promoted antigen escape from endosomes to the cytosol for degradation by proteasomes into peptides for MHC I loading by TAP-dependent pathways. Furthermore, we found that induction of lipid bodies (LBs) and alterations in LB composition mediated by ADJ were also critical for DC cross-presentation. Collectively, our model challenges the prevailing metabolic paradigm by suggesting that DCs can perform effective DC cross-presentation, independent of glycolysis to induce robust T cell-dependent protective immunity to intracellular pathogens. These findings have strong implications in the rational development of safe and effective immune adjuvants to potentiate robust T-cell based immunity.


Assuntos
Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/fisiologia , Resinas Acrílicas/química , Adjuvantes Imunológicos/farmacologia , Apresentação do Antígeno/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , NADPH Oxidase 2/fisiologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
Redox Biol ; 38: 101810, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33360293

RESUMO

The recent global pandemic due to COVID-19 is caused by a type of coronavirus, SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2). Despite rigorous efforts worldwide to control the spread and human to human transmission of this virus, incidence and death due to COVID-19 continue to rise. Several drugs have been tested for treatment of COVID-19, including hydroxychloroquine. While a number of studies have shown that hydroxychloroquine can prolong QT interval, potentially increasing risk of ventricular arrhythmias and Torsade de Pointes, its effects on immune cell function have not been extensively examined. In the current review, an overview of coronaviruses, viral entry and pathogenicity, immunity upon coronavirus infection, and current therapy options for COVID-19 are briefly discussed. Further based on preclinical studies, we provide evidences that i) hydroxychloroquine impairs autophagy, which leads to accumulation of damaged/oxidized cytoplasmic constituents and interferes with cellular homeostasis, ii) this impaired autophagy in part reduces antigen processing and presentation to immune cells and iii) inhibition of endosome-lysosome system acidification by hydroxychloroquine not only impairs the phagocytosis process, but also potentially alters pulmonary surfactant in the lungs. Therefore, it is likely that hydroxychloroquine treatment may in fact impair host immunity in response to SARS-CoV-2, especially in elderly patients or those with co-morbidities. Further, this review provides a rationale for developing and selecting antiviral drugs and includes a brief review of traditional strategies combined with new drugs to combat COVID-19.


Assuntos
Apresentação do Antígeno/efeitos dos fármacos , Antivirais , Morte Celular Autofágica , Hidroxicloroquina , Pandemias , /imunologia , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Morte Celular Autofágica/efeitos dos fármacos , Morte Celular Autofágica/imunologia , /epidemiologia , /patologia , Humanos , Hidroxicloroquina/efeitos adversos , Hidroxicloroquina/uso terapêutico , Oxirredução/efeitos dos fármacos
4.
Nature ; 581(7806): 100-105, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376951

RESUMO

Immune evasion is a major obstacle for cancer treatment. Common mechanisms of evasion include impaired antigen presentation caused by mutations or loss of heterozygosity of the major histocompatibility complex class I (MHC-I), which has been implicated in resistance to immune checkpoint blockade (ICB) therapy1-3. However, in pancreatic ductal adenocarcinoma (PDAC), which is resistant to most therapies including ICB4, mutations that cause loss of MHC-I are rarely found5 despite the frequent downregulation of MHC-I expression6-8. Here we show that, in PDAC, MHC-I molecules are selectively targeted for lysosomal degradation by an autophagy-dependent mechanism that involves the autophagy cargo receptor NBR1. PDAC cells display reduced expression of MHC-I at the cell surface and instead demonstrate predominant localization within autophagosomes and lysosomes. Notably, inhibition of autophagy restores surface levels of MHC-I and leads to improved antigen presentation, enhanced anti-tumour T cell responses and reduced tumour growth in syngeneic host mice. Accordingly, the anti-tumour effects of autophagy inhibition are reversed by depleting CD8+ T cells or reducing surface expression of MHC-I. Inhibition of autophagy, either genetically or pharmacologically with chloroquine, synergizes with dual ICB therapy (anti-PD1 and anti-CTLA4 antibodies), and leads to an enhanced anti-tumour immune response. Our findings demonstrate a role for enhanced autophagy or lysosome function in immune evasion by selective targeting of MHC-I molecules for degradation, and provide a rationale for the combination of autophagy inhibition and dual ICB therapy as a therapeutic strategy against PDAC.


Assuntos
Adenocarcinoma/imunologia , Autofagia/imunologia , Carcinoma Ductal Pancreático/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias Pancreáticas/imunologia , Evasão Tumoral/imunologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Apresentação do Antígeno/imunologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/imunologia , Linhagem Celular Tumoral , Cloroquina/farmacologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Evasão Tumoral/efeitos dos fármacos
5.
Med Hypotheses ; 140: 109756, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32344306
6.
Cell ; 180(5): 895-914.e27, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142680

RESUMO

A safe and controlled manipulation of endocytosis in vivo may have disruptive therapeutic potential. Here, we demonstrate that the anti-emetic/anti-psychotic prochlorperazine can be repurposed to reversibly inhibit the in vivo endocytosis of membrane proteins targeted by therapeutic monoclonal antibodies, as directly demonstrated by our human tumor ex vivo assay. Temporary endocytosis inhibition results in enhanced target availability and improved efficiency of natural killer cell-mediated antibody-dependent cellular cytotoxicity (ADCC), a mediator of clinical responses induced by IgG1 antibodies, demonstrated here for cetuximab, trastuzumab, and avelumab. Extensive analysis of downstream signaling pathways ruled out on-target toxicities. By overcoming the heterogeneity of drug target availability that frequently characterizes poorly responsive or resistant tumors, clinical application of reversible endocytosis inhibition may considerably improve the clinical benefit of ADCC-mediating therapeutic antibodies.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/imunologia , Neoplasias/tratamento farmacológico , Proclorperazina/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Apresentação do Antígeno/efeitos dos fármacos , Biópsia , Cetuximab/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Endocitose/efeitos dos fármacos , Endocitose/imunologia , Xenoenxertos , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células MCF-7 , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Trastuzumab/farmacologia
7.
Cancer Immunol Immunother ; 69(6): 1029-1042, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32100075

RESUMO

Mature dendritic cells (DCs) represent cellular adjuvants for optimal antigen presentation in cancer vaccines. Recently, a combination of prostaglandin E2 (PGE2) with Toll-like receptor agonists (TLR-P) was proposed as a new standard to generate superior cytokine-producing DCs with high migratory capacity. Here, we compare TLR-P DCs with conventional DCs matured only with the proinflammatory cytokines TNFα and IL-1ß (CDCs), focussing on the interaction of resulting DCs with CD8+ T-cells. TLR-P matured DCs showed elevated expression of activation markers such as CD80 and CD83 compared to CDCs, together with a significantly higher migration capacity. Secretion of IL-6, IL-8, IL-10, and IL-12 was highest after 16 h in TLR-P DCs, and only TLR-P DCs secreted active IL-12p70. TLR-P DCs as well as CDCs successfully primed multifunctional CD8+ T-cells from naïve precursors specific for the peptide antigens Melan-A, NLGN4X, and PTP with comparable priming efficacy and T-cell receptor avidity. CD8+ T-cells primed by TLR-P DCs showed significantly elevated expression of the integrin VLA-4 and a trend for higher T-cell numbers after expansion. In contrast, TLR-P DCs displayed a substantially reduced capability to cross-present CMVpp65 protein antigen to pp65-specific T cells, an effect that was dose-dependent on PGE2 during DC maturation and reproducible with several responder T-cell lines. In conclusion, TLR-P matured DCs might be optimal presenters of antigens not requiring processing such as short peptides. However, PGE2 seems less favorable for maturation of DCs intended to process and cross-present more complex vaccine antigens such as lysates, proteins or long peptides.


Assuntos
Apresentação do Antígeno/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Dinoprostona/uso terapêutico , Receptor 3 Toll-Like/imunologia , Movimento Celular , Apresentação Cruzada , Dinoprostona/farmacologia , Humanos
8.
Nat Med ; 26(3): 430-440, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32066977

RESUMO

Adjuvants are central to the efficacy of subunit vaccines. Aluminum hydroxide (alum) is the most commonly used vaccine adjuvant, yet its adjuvanticity is often weak and mechanisms of triggering antibody responses remain poorly understood. We demonstrate that site-specific modification of immunogens with short peptides composed of repeating phosphoserine (pSer) residues enhances binding to alum and prolongs immunogen bioavailability. The pSer-modified immunogens formulated in alum elicited greatly increased germinal center, antibody, neutralizing antibody, memory and long-lived plasma cell responses compared to conventional alum-adsorbed immunogens. Mechanistically, pSer-immunogen:alum complexes form nanoparticles that traffic to lymph nodes and trigger B cell activation through multivalent and oriented antigen display. Direct uptake of antigen-decorated alum particles by B cells upregulated antigen processing and presentation pathways, further enhancing B cell activation. These data provide insights into mechanisms of action of alum and introduce a readily translatable approach to significantly improve humoral immunity to subunit vaccines using a clinical adjuvant.


Assuntos
Adjuvantes Imunológicos/farmacologia , Hidróxido de Alumínio/farmacologia , Imunidade Humoral/efeitos dos fármacos , Peptídeos/imunologia , Engenharia de Proteínas , Animais , Apresentação do Antígeno/efeitos dos fármacos , Antígenos/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Endocitose/efeitos dos fármacos , Epitopos/imunologia , Imunização , Memória Imunológica/efeitos dos fármacos , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanopartículas/química , Peptídeos/química , Fosfosserina/metabolismo
9.
Lab Anim (NY) ; 49(3): 79-88, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32042160

RESUMO

The intestinal immune system samples luminal contents to induce adaptive immune responses that include tolerance in the steady state and protective immunity during infection. How luminal substances are delivered to the immune system has not been fully investigated. Goblet cells have an important role in this process by delivering luminal substances to the immune system through the formation of goblet cell-associated antigen passages (GAPs). Soluble antigens in the intestinal lumen are transported across the epithelium transcellularly through GAPs and delivered to dendritic cells for presentation to T cells and induction of immune responses. GAPs can be identified and quantified by using the ability of GAP-forming goblet cells to take up fluorescently labeled dextran. Here, we describe a method to visualize GAPs and other cells that have the capacity to take up luminal substances by intraluminal injection of fluorescent dextran in mice under anesthesia, tissue sectioning for slide preparation and imaging with fluorescence microscopy. In contrast to in vivo two-photon imaging previously used to identify GAPs, this technique is not limited by anatomical constraints and can be used to visualize GAP formation throughout the length of the intestine. In addition, this method can be combined with common immunohistochemistry protocols to visualize other cell types. This approach can be used to compare GAP formation following different treatments or changes to the luminal environment and to uncover how sampling of luminal substances is altered in pathophysiological conditions. This protocol requires 8 working hours over 2-3 d to be completed.


Assuntos
Antígenos/metabolismo , Colo/imunologia , Células Dendríticas/imunologia , Células Caliciformes/imunologia , Vigilância Imunológica , Intestino Delgado/imunologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Antígenos/imunologia , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Dextranos/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Células Caliciformes/efeitos dos fármacos , Mucosa Intestinal/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/imunologia , Ovalbumina/administração & dosagem , Projetos de Pesquisa
10.
J Med Chem ; 63(6): 3348-3358, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32109056

RESUMO

ER aminopeptidase 1 (ERAP1) is an intracellular enzyme that generates antigenic peptides and is an emerging target for cancer immunotherapy and the control of autoimmunity. ERAP1 inhibitors described previously target the active site and are limited in selectivity, minimizing their clinical potential. To address this, we targeted the regulatory site of ERAP1 using a high-throughput screen and discovered a small molecule hit that is highly selective for ERAP1. (4aR,5S,6R,8S,8aR)-5-(2-(Furan-3-yl)ethyl)-8-hydroxy-5,6,8a-trimethyl-3,4,4a,5,6,7,8,8a-octahydronaphthalene-1-carboxylic acid is a natural product found in Dodonaea viscosa that constitutes a submicromolar, highly selective, and cell-active modulator of ERAP1. Although the compound activates hydrolysis of small model substrates, it is a competitive inhibitor for physiologically relevant longer peptides. Crystallographic analysis confirmed that the compound targets the regulatory site of the enzyme that normally binds the C-terminus of the peptide substrate. Our findings constitute a novel starting point for the development of selective ERAP1 modulators that have potential for further clinical development.


Assuntos
Aminopeptidases/antagonistas & inibidores , Apresentação do Antígeno/efeitos dos fármacos , Diterpenos Clerodânicos/farmacologia , Epitopos/metabolismo , Peptídeos/metabolismo , Inibidores de Proteases/farmacologia , Sítio Alostérico , Aminopeptidases/química , Aminopeptidases/metabolismo , Animais , Domínio Catalítico , Cristalografia por Raios X , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/metabolismo , Ativadores de Enzimas/química , Ativadores de Enzimas/metabolismo , Ativadores de Enzimas/farmacologia , Epitopos/química , Células HeLa , Humanos , Camundongos , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/metabolismo , Peptídeos/química , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Ligação Proteica , Proteólise/efeitos dos fármacos
11.
Cancer Res ; 80(4): 732-746, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31848196

RESUMO

There is a critical need to understand mechanisms of resistance and to develop combinatorial strategies to improve responses to checkpoint blockade immunotherapy (CBI). Here, we uncover a novel mechanism by which the human papillomavirus (HPV) inhibits the activity of CBI in head and neck squamous cell carcinoma (HNSCC). Using orthotopic HNSCC models, we show that radiation combined with anti-PD-L1 immunotherapy significantly enhanced local control, CD8+ memory T cells, and induced preferential T-cell homing via modulation of vascular endothelial cells. However, the HPV E5 oncoprotein suppressed immune responses by downregulating expression of major histocompatibility complex and interfering with antigen presentation in murine models and patient tumors. Furthermore, tumors expressing HPV E5 were rendered entirely resistant to anti-PD-L1 immunotherapy, and patients with high expression of HPV16 E5 had worse survival. The antiviral E5 inhibitor rimantadine demonstrated remarkable single-agent antitumor activity. This is the first report that describes HPV E5 as a mediator of resistance to anti-PD-1/PD-L1 immunotherapy and demonstrates the antitumor activity of rimantadine. These results have broad clinical relevance beyond HNSCC to other HPV-associated malignancies and reveal a powerful mechanism of HPV-mediated immunosuppression, which can be exploited to improve response rates to checkpoint blockade. SIGNIFICANCE: This study identifies a novel mechanism of resistance to anti-PD-1/PD-L1 immunotherapy mediated by HPV E5, which can be exploited using the HPV E5 inhibitor rimantadine to improve outcomes for head and neck cancer patients. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/4/732/F1.large.jpg.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias de Cabeça e Pescoço/terapia , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus/terapia , Rimantadina/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Adolescente , Adulto , Idoso , Animais , Apresentação do Antígeno/efeitos dos fármacos , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral/transplante , Quimiorradioterapia/métodos , Estudos de Coortes , Modelos Animais de Doenças , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/virologia , Voluntários Saudáveis , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 16/metabolismo , Papillomavirus Humano 16/patogenicidade , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/antagonistas & inibidores , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Células RAW 264.7 , RNA-Seq , Rimantadina/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Adulto Jovem
12.
Protein Pept Lett ; 27(1): 60-66, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31362652

RESUMO

BACKGROUND: Cathelicidins are a family of Host Defense Peptides (HDPs), that play an important role in the innate immune response. They exert both broad-spectrum antimicrobial activity against pathogens, and strong immunomodulatory functions that affect the response of innate and adaptive immune cells. OBJECTIVE: The aim of this study was to investigate immunomodulation by the chicken cathelicidin CATH-2 and compare its activities to those of the human cathelicidin LL-37. METHODS: Chicken macrophages and chicken monocytes were incubated with cathelicidins. Activation of immune cells was determined by measuring surface markers Mannose Receptor Ctype 1 (MRC1) and MHC-II. Cytokine production was measured by qPCR and nitric oxide production was determined using the Griess assay. Finally, the effect of cathelicidins on phagocytosis was measured using carboxylate-modified polystyrene latex beads. RESULTS: CATH-2 and its all-D enantiomer D-CATH-2 increased MRC1 and MHC-II expression, markers for antigen presentation, on primary chicken monocytes, whereas LL-37 did not. D-CATH- 2 also increased the MRC1 and MHC-II expression if a chicken macrophage cell line (HD11 cells) was used. In addition, LPS-induced NO production by HD11 cells was inhibited by CATH-2 and D-CATH-2. CONCLUSION: These results are a clear indication that CATH-2 (and D-CATH-2) affect the activation state of monocytes and macrophages, which leads to optimization of the innate immune response and enhancement of the adaptive immune response.


Assuntos
Biomarcadores/metabolismo , Catelicidinas/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo , Sequência de Aminoácidos , Animais , Apresentação do Antígeno/efeitos dos fármacos , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem Celular , Galinhas , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/genética , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo
13.
Int Immunopharmacol ; 78: 106111, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31881524

RESUMO

Over the past decade, studies have identified subset of B cells, which play suppressive functions in additions to the conventional functions of B cells: antigen processing and presentation, activation of T cells and antibody productions. Because of their regulatory function, they were named as B regulatory cells (Bregs). Bregs restrict the severity of autoimmune disorders in animal disease models such as experimental autoimmune myocarditis (EAM), experimental autoimmune encephalitis (EAE), and collagen-induced arthritis (CIA) but can contribute to the development of infection and cancer. In humans, the roles of B regulatory cells in autoimmune diseases have not been clearly established because of the inconsistent findings from many researchers. This is believed to arise from the speculated fact that Bregs lack specific marker, which can be used to identify and characterize them in human diseases. The CD19+CD24hiCD38hiCD1dhiB cells have been associated with the regulatory function. Available evidences highlight the relevance of increasing IL-10-producing B cells in autoimmune diseases and the possibility of serving as new therapeutic targets in inflammatory disorders. This review empanels the functions of Bregs in autoimmune diseases in both human and animal models, and further evaluates the possibility of Bregs as therapeutic targets in inflammatory disorders. Consequently, this might help identify possible research gaps, which need to be clarified as researchers speculate the possibility of targeting some subsets of Bregs in the treatment of inflammatory disorders.


Assuntos
Doenças Autoimunes/imunologia , Linfócitos B Reguladores/imunologia , Imunossupressores/farmacologia , Inflamação/imunologia , Interleucina-10/metabolismo , Transferência Adotiva/métodos , Animais , Apresentação do Antígeno/efeitos dos fármacos , Doenças Autoimunes/terapia , Linfócitos B Reguladores/efeitos dos fármacos , Linfócitos B Reguladores/metabolismo , Linfócitos B Reguladores/transplante , Comunicação Celular/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Imunossupressores/uso terapêutico , Inflamação/terapia , Mediadores da Inflamação/metabolismo , Interleucina-10/agonistas , Interleucina-10/imunologia , Células Th1/imunologia , Células Th2/imunologia
14.
Cells ; 8(12)2019 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-31817841

RESUMO

Transporter associated with antigen processing (TAP), a key player in the major histocompatibility complex class I-restricted antigen presentation, makes an attractive target for viruses that aim to escape the immune system. Mechanisms of TAP inhibition vary among virus species. Bovine herpesvirus 1 (BoHV-1) is unique in its ability to target TAP for proteasomal degradation following conformational arrest by the UL49.5 gene product. The exact mechanism of TAP removal still requires elucidation. For this purpose, a TAP-GFP (green fluorescent protein) fusion protein is instrumental, yet GFP-tagging may affect UL49.5-induced degradation. Therefore, we constructed a series of TAP-GFP variants using various linkers to obtain an optimal cellular fluorescent TAP platform. Mel JuSo (MJS) cells with CRISPR/Cas9 TAP1 or TAP2 knockouts were reconstituted with TAP-GFP constructs. Our results point towards a critical role of GFP localization on fluorescent properties of the fusion proteins and, in concert with the type of a linker, on the susceptibility to virally-induced inhibition and degradation. The fluorescent TAP platform was also used to re-evaluate TAP stability in the presence of other known viral TAP inhibitors, among which only UL49.5 was able to reduce TAP levels. Finally, we provide evidence that BoHV-1 UL49.5-induced TAP removal is p97-dependent, which indicates its degradation via endoplasmic reticulum-associated degradation (ERAD).


Assuntos
Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Herpesvirus Bovino 1/patogenicidade , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Acetanilidas/farmacologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Apresentação do Antígeno/genética , Benzotiazóis/farmacologia , Bovinos , Linhagem Celular , Linhagem Celular Tumoral , Citometria de Fluxo , Imunofluorescência , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Immunoblotting , Imunoprecipitação , Plasmídeos/genética
15.
Nanoscale ; 11(45): 21782-21789, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31709434

RESUMO

For efficient cancer vaccines, the antitumor function largely relies on cytotoxic T cells, whose activation can be effectively induced via antigen-encoding mRNA, making mRNA-based cancer vaccines an attractive approach for personalized cancer therapy. While the liposome-based delivery system enables the systemic delivery and transfection of mRNA, incorporating an adjuvant that is non-lipid like remains challenging, although the co-delivery of mRNA (antigen) and effective adjuvant is key to the activation of the cytotoxic T cells. This is because the presence of an adjuvant is important for dendritic cell maturation-another necessity for cytotoxic T cell activation. In the present work, we designed a poly (lactic-co-glycolic acid) (PLGA)-core/lipid-shell hybrid nanoparticle carrier for the co-delivery of mRNA and gardiquimod (adjuvant that cannot be incorporated into the lipid shell). We demonstrated in the present work that the co-delivery of mRNA and gardiquimod led to the effective antigen expression and DC maturation in vitro. The intravenous administration of the hybrid nanovaccine resulted in the enrichment of mRNA expression in the spleen and a strong immune response in vivo. The simultaneous delivery of the antigen and adjuvant both spatially and temporally via the core/shell nanoparticle carrier is found to be beneficial for tumor growth inhibition.


Assuntos
Adjuvantes Imunológicos , Aminoquinolinas , Vacinas Anticâncer , Imidazóis , Nanopartículas , Neoplasias Experimentais , RNA Neoplásico , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacocinética , Adjuvantes Imunológicos/farmacologia , Aminoquinolinas/química , Aminoquinolinas/farmacocinética , Aminoquinolinas/farmacologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Apresentação do Antígeno/imunologia , Vacinas Anticâncer/química , Vacinas Anticâncer/farmacocinética , Vacinas Anticâncer/farmacologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Células Dendríticas/patologia , Imidazóis/química , Imidazóis/farmacocinética , Imidazóis/farmacologia , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/farmacologia , RNA Neoplásico/química , RNA Neoplásico/farmacocinética , RNA Neoplásico/farmacologia , Linfócitos T Citotóxicos/imunologia
16.
Cancer Cell ; 36(4): 385-401.e8, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31564637

RESUMO

Loss of MHC class I (MHC-I) antigen presentation in cancer cells can elicit immunotherapy resistance. A genome-wide CRISPR/Cas9 screen identified an evolutionarily conserved function of polycomb repressive complex 2 (PRC2) that mediates coordinated transcriptional silencing of the MHC-I antigen processing pathway (MHC-I APP), promoting evasion of T cell-mediated immunity. MHC-I APP gene promoters in MHC-I low cancers harbor bivalent activating H3K4me3 and repressive H3K27me3 histone modifications, silencing basal MHC-I expression and restricting cytokine-induced upregulation. Bivalent chromatin at MHC-I APP genes is a normal developmental process active in embryonic stem cells and maintained during neural progenitor differentiation. This physiological MHC-I silencing highlights a conserved mechanism by which cancers arising from these primitive tissues exploit PRC2 activity to enable immune evasion.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Regulação Neoplásica da Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Neoplasias/imunologia , Complexo Repressor Polycomb 2/metabolismo , Evasão Tumoral/genética , Animais , Apresentação do Antígeno/efeitos dos fármacos , Apresentação do Antígeno/imunologia , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Metilação de DNA/imunologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Resistencia a Medicamentos Antineoplásicos/genética , Repressão Epigenética/efeitos dos fármacos , Repressão Epigenética/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Código das Histonas/efeitos dos fármacos , Humanos , Camundongos , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Complexo Repressor Polycomb 2/antagonistas & inibidores , Linfócitos T/imunologia , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
JCI Insight ; 4(18)2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31487265

RESUMO

Autoimmune diseases resulting from MHC class II-restricted autoantigen-specific T cell immunity include the systemic inflammatory autoimmune conditions rheumatoid arthritis and vasculitis. While currently treated with broad-acting immunosuppressive drugs, a preferable strategy is to regulate antigen-specific effector T cells (Teffs) to restore tolerance by exploiting DC antigen presentation. We targeted draining lymph node (dLN) phagocytic DCs using liposomes encapsulating 1α,25-dihydroxyvitamin D3 (calcitriol) and antigenic peptide to elucidate mechanisms of tolerance used by DCs and responding T cells under resting and immunized conditions. PD-L1 expression was upregulated in dLNs of immunized relative to naive mice. Subcutaneous administration of liposomes encapsulating OVA323-339 and calcitriol targeted dLN PD-L1hi DCs of immunized mice and reduced their MHC class II expression. OVA323-339/calcitriol liposomes suppressed expansion, differentiation, and function of Teffs and induced Foxp3+ and IL-10+ peripheral Tregs in an antigen-specific manner, which was dependent on PD-L1. Peptide/calcitriol liposomes modulated CD40 expression by human DCs and promoted Treg induction in vitro. Liposomes encapsulating calcitriol and disease-associated peptides suppressed the severity of rheumatoid arthritis and Goodpasture's vasculitis models with suppression of antigen-specific memory T cell differentiation and function. Accordingly, peptide/calcitriol liposomes leverage DC PD-L1 for antigen-specific T cell regulation and induce antigen-specific tolerance in inflammatory autoimmune diseases.


Assuntos
Doença Antimembrana Basal Glomerular/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Calcitriol/administração & dosagem , Células Dendríticas/imunologia , Epitopos Imunodominantes/administração & dosagem , Transferência Adotiva , Animais , Doença Antimembrana Basal Glomerular/diagnóstico , Doença Antimembrana Basal Glomerular/imunologia , Apresentação do Antígeno/efeitos dos fármacos , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Células CHO , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Cricetulus , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/transplante , Modelos Animais de Doenças , Feminino , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Tolerância Imunológica/efeitos dos fármacos , Epitopos Imunodominantes/imunologia , Memória Imunológica/efeitos dos fármacos , Injeções Subcutâneas , Lipossomos , Linfonodos/citologia , Camundongos , Camundongos Transgênicos , Ovalbumina/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Índice de Gravidade de Doença , Linfócitos T/imunologia , Linfócitos T/metabolismo
18.
Cancer Immunol Res ; 7(12): 1984-1997, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31540894

RESUMO

T-cell immunotherapies are often thwarted by the limited presentation of tumor-specific antigens abetted by the downregulation of human leukocyte antigen (HLA). We showed that drugs inhibiting ALK and RET produced dose-related increases in cell-surface HLA in tumor cells bearing these mutated kinases in vitro and in vivo, as well as elevated transcript and protein expression of HLA and other antigen-processing machinery. Subsequent analysis of HLA-presented peptides after ALK and RET inhibitor treatment identified large changes in the immunopeptidome with the appearance of hundreds of new antigens, including T-cell epitopes associated with impaired peptide processing (TEIPP) peptides. ALK inhibition additionally decreased PD-L1 levels by 75%. Therefore, these oncogenes may enhance cancer formation by allowing tumors to evade the immune system by downregulating HLA expression. Altogether, RET and ALK inhibitors could enhance T-cell-based immunotherapies by upregulating HLA, decreasing checkpoint blockade ligands, and revealing new, immunogenic, cancer-associated antigens.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antígenos de Neoplasias/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Animais , Apresentação do Antígeno/efeitos dos fármacos , Linhagem Celular Tumoral , Crizotinibe/farmacologia , Feminino , Humanos , Camundongos Transgênicos , Neoplasias/imunologia , Peptídeos/imunologia , Pirimidinas/farmacologia , Sulfonas/farmacologia
19.
Immunopharmacol Immunotoxicol ; 41(4): 513-520, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31397191

RESUMO

Exposure to environmentally relevant doses of arsenic has several harmful effects on the human immune system. In traditional Eastern medicines, nettle has been used as an anti-inflammatory agent to treat rheumatism and osteoarthritis. Fumaric acid (FA) as a major effective compound in nettle was chosen based on very accurate virtual screening to find antagonist for TLR4/MD structure. In this study, the in vitro therapeutic effects of FA on arsenic-exposed monocytes-derived dendritic cells (MDDCs) were evaluated. All the canonical functions of dendritic cells in bridging innate and adaptive immune system including phagocytosis and antigen-presenting capacity, and also cytokines secretion, were evaluated after exposure to arsenic/FA. FA profoundly over-expressed antigen-presenting capacity of MDDCs after exposure to arsenic through the upregulation of MHCιι. However, phagocytosis capacity of arsenic-exposed MDDCs is not compensated for, by treatment with FA. Arsenic up-regulates pro-inflammatory cytokines independents of TLR4 pathway. FA surprisingly mitigates the up-regulation of IL-1ß and TNF-α but not TLR4 and NF-kB. Moreover, FA increases the viability of MDDCs even at a high dose of arsenic. Totally, FA reduced inflammatory factors induced by arsenic. This finding confirmed that nettle and other medicinal plants containing similar structures with FA could be further analyzed as valuable candidates for the reduction of drastic effects of arsenic in human immune systems.


Assuntos
Arsênico/farmacologia , Células Dendríticas/efeitos dos fármacos , Fumaratos/farmacologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Monócitos/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Imunidade Adaptativa/efeitos dos fármacos , Adulto , Apresentação do Antígeno/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Inflamação/metabolismo , Masculino , Monócitos/metabolismo , Fagocitose/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
20.
Biochem Biophys Res Commun ; 518(1): 87-93, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31402120

RESUMO

GLM, a luteolin derivative, shows anti-melanogenic effect via regulation of various signal molecules; however, it is unclear whether it also exerts anti-inflammatory effect. This study investigated the mechanisms of the anti-inflammatory effect of GLM on activated dendritic cells (DCs) to elucidate its therapeutic potential for ulcerative colitis. The anti-inflammatory effect of GLM was firstly investigated based on its effect on DCs maturation and T cells proliferation/activation. GLM treatment downregulated pro-inflammatory cytokine productions, surface molecule expression, and antigen-presenting ability for MHC-II complex in LPS-activated DCs. Importantly, anti-inflammatory effect induced by GLM treatment were independent of MAPK/NF-κB signaling pathways. Furthermore, DCs that were co-treated with LPS and GLM impaired the proliferation and activation of naïve CD4+ T cells. Interestingly, GLM exerted in vivo protective effect in DSS-induced colitis models by decreasing Th1, Th2, and Th17 cells and myeloperoxidase (MPO) levels, as well as restoring body weight, disease activity, and DSS-induced pathology. Based on these results, GLM was shown to be a potential candidate treatment for ulcerative colitis.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Células Dendríticas/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Luteolina/uso terapêutico , Animais , Apresentação do Antígeno/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Colite Ulcerativa/complicações , Citocinas/biossíntese , Células Dendríticas/efeitos dos fármacos , Sulfato de Dextrana , Feminino , Inflamação/complicações , Lipopolissacarídeos , Luteolina/química , Luteolina/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fenótipo , Fator de Transcrição RelA/metabolismo
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