RESUMO
BACKGROUND: Human T-cell lymphotropic virus type 1 (HTLV-1), also denominated Human T-cell leukemia virus-1, induces immune activation and secretion of proinflammatory cytokines, especially in individuals with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Regulatory T lymphocytes (Tregs) may control of inflammation through the production of regulatory cytokines, including IL10 and TGF-ß. In this study we determined the frequencies of CD4 + and CD8 + Tregs in a HAM/TSP population, compared to asymptomatic carriers and uninfected individuals, as well as investigated the profiles of regulatory and inflammatory cytokines. METHODS: Asymptomatic HTLV-1 carriers and HAM/TSP patients were matched by sex and age. The frequencies of IL10- and/or TGF-ß-producing Tregs were quantified by flow cytometry. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used to quantify HTLV-1 proviral load and the mRNA expression of cytokines and cellular receptors in peripheral blood mononuclear cells. RESULTS: Total frequencies of CD4 + Tregs, as well as the IL10-producing CD4 + and CD8 + Treg subsets, were statistically higher in patients with HAM/TSP compared to asymptomatic HTLV-1-infected individuals. In addition, a positive correlation was found between the frequency of CD4 + IL10 + Tregs and proviral load in the HAM/TSP patients evaluated. A positive correlation was also observed between gene expression of proinflammatory versus regulatory cytokines only in HAM / TSP group. CONCLUSIONS: A higher frequencies of IL10-producing Tregs were identified in patients with HAM/TSP. Imbalanced production of IL10 in relation to TGF-ß may contribute to the increased inflammatory response characteristically seen in HAM/TSP patients.
Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Interleucina-10 , Paraparesia Espástica Tropical , Linfócitos T Reguladores , Fator de Crescimento Transformador beta , Humanos , Linfócitos T Reguladores/imunologia , Masculino , Feminino , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/virologia , Interleucina-10/imunologia , Interleucina-10/genética , Pessoa de Meia-Idade , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Fator de Crescimento Transformador beta/metabolismo , Adulto , Carga Viral , Idoso , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/virologia , Portador Sadio/imunologia , Portador Sadio/virologiaRESUMO
Chronic hepatitis C (CHC) pathogenic mechanisms as well as the participation of the immune response in the generation of liver damage are still a topic of interest. Here, we evaluated immune cell populations and cytokines in the liver and peripheral blood (PB) to elucidate their role in CHC pathogenesis. B, CTL, Th, Treg, Th1, Th17, and NK cell localization and frequency were evaluated on liver biopsies by immunohistochemistry, while frequency, differentiation, and functional status on PB were evaluated by flow cytometry. TNF-α, IL-23, IFN-γ, IL-1ß, IL-6, IL-8, IL-17A, IL-21, IL-10, and TGF-ß expression levels were quantified in fresh liver biopsy by RT-qPCR and in plasma by CBA/ELISA. Liver CTL and Th1 at the lobular area inversely correlated with viral load (r = -0.469, p =0.003 and r = -0.384, p = 0.040). Treg correlated with CTL and Th1 at the lobular area (r = 0.784, p < 0.0001; r = 0.436, p = 0.013). Th17 correlated with hepatic IL-8 (r = 0.52, p < 0.05), and both were higher in advanced fibrosis cases (Th17 p = 0.0312, IL-8 p = 0.009). Hepatic cytokines were higher in severe hepatitis cases (IL-1ß p = 0.026, IL-23 p = 0.031, IL-8 p = 0.002, TGF-ß, p= 0.037). Peripheral NK (p = 0.008) and NK dim (p = 0.018) were diminished, while NK bright (p = 0.025) was elevated in patients vs. donors. Naïve Th (p = 0.011) and CTL (p = 0.0007) were decreased, while activated Th (p = 0.0007) and CTL (p = 0.0003) were increased. IFN-γ production and degranulation activity in NK and CTL were normal. Peripheral cytokines showed an altered profile vs. donors, particularly elevated IL-6 (p = 0.008) and TGF-ß (p = 0.041). Total hepatic CTLs favored damage. Treg could not prevent fibrogenesis triggered by Th17 and IL-8. Peripheral T-lymphocyte differentiation stage shift, elevated cytokine levels and NK-cell count decrease would contribute to global disease.
Assuntos
Hepatite C Crônica , Humanos , Imunidade , Linfócitos T Reguladores , Células Th17RESUMO
OBJECTIVE: CAR-T cell therapy has revolutionized the treatment of oncological diseases, and potential uses in autoimmune diseases have recently been described. The review aims to integrate the available data on treatment with CAR-T cells, emphasizing autoimmune diseases, to determine therapeutic advances and their possible future clinical applicability in autoimmunity. MATERIALS AND METHODS: A search was performed in PubMed with the keywords "Chimeric Antigen Receptor" and "CART cell". The documents of interest were selected, and a critical review of the information was carried out. RESULTS: In the treatment of autoimmune diseases, in preclinical models, three different cellular strategies have been used, which include Chimeric antigen receptor T cells, Chimeric autoantibody receptor T cells, and Chimeric antigen receptor in regulatory T lymphocytes. All three types of therapy have been effective. The potential adverse effects within them, cytokine release syndrome, cellular toxicity and neurotoxicity must always be kept in mind. CONCLUSIONS: Although information in humans is not yet available, preclinical models of CAR-T cells in the treatment of autoimmune diseases show promising results, so that in the future, they may become a useful and effective therapy in the treatment of these pathologies.
Assuntos
Doenças Autoimunes/terapia , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos/imunologia , Animais , HumanosRESUMO
Despite the success and ongoing promise of monoclonal antibody-targeted immune checkpoint inhibitor immunotherapy of advanced malignancies, in particular, antibodies directed against CTLA-4 and PD-1/PD-L1, the development of immune-related adverse events (irAEs) remains a constraint of this type of therapy. Although rarely fatal, the occurrence of irAEs may necessitate discontinuation of immunotherapy, as well as administration of corticosteroids or other immunosuppressive therapies that may not only compromise efficacy but also predispose for development of opportunistic infection. Clearly, retention of efficacy of immune checkpoint-targeted therapies with concurrent attenuation of immune-mediated toxicity represents a formidable challenge. In this context, the current brief review examines mechanistic relationships between these events, as well as recent insights into immunopathogenesis, and strategies which may contribute to resolving this issue. These sections are preceded by brief overviews of the discovery and functions of CTLA-4 and PD-1, as well as the chronology of the development of immunotherapeutic monoclonal antibodies which target these immune checkpoint inhibitors.
Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Imunoterapia/efeitos adversos , Neoplasias/terapia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/uso terapêutico , Oncologia/métodos , Oncologia/tendências , Neoplasias/epidemiologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologiaRESUMO
This systematic review aimed to: (a) generate a descriptive synthesis of preclinical studies assessing the therapeutic potential of regulatory T lymphocytes (Tregs) to arrest periodontitis, (b) evaluate the methodological heterogeneity of the reviewed animal studies and (c) assess the risk of bias (RoB) of the included studies. The electronic search for animal studies included the MEDLINE, EMBASE, Web of Science and LILACS databases. In addition, a manual search assessed the high-ranked scientific journals in "periodontics/immunology" and the references listed in the included studies. There were no language, year or publication status restrictions. Two independent reviewers selected and extracted the data, and Cohen's Kappa coefficient was calculated to determine the inter-examiner agreement. The Systematic Review Center for Laboratory Animal Experimentation's (SYRCLE) tool was used to assess the RoB. A total of 21 of the 425 studies obtained from the database search were included. Treg function was mainly described in Porphyromonas gingivalis-induced periodontitis (57.1%) in mice (76.2%), where Treg suppression was strongly related to disease progression and Treg induction was strongly related to immuno-inflammatory response reduction. Of those 21 studies, eight included eight animal experiments using three distinct therapeutic approaches, including: P. gingivalis-driven immunization (n = 3), retinoic acid inoculation (n = 2) and anti-inflammatory molecules in polymeric carriers (n = 3), which could modulate the Treg activity through cytokine production (interleukin-10 and transforming growth factor-ß1), CC-chemokine- and CC-chemokine receptor-mediated chemoattraction (CCL22 and CCR4) or Th17-associated receptor activator of nuclear factor κB ligand (RANKL) downregulation. However, the studies with animal experiments did not specify the randomization sequences and housing conditions that were used, and therefore, 42.11% of the entries were rated as unclear RoB. Distinct therapeutic strategies involving Tregs could potentially suppress the immuno-inflammatory response and restore alveolar bone homeostasis during periodontitis. Nevertheless, important methodological variability, poor reporting of treatment effect estimates and unclear RoB suggest using caution when assessing the results of these studies.
Assuntos
Periodontite/imunologia , Periodontite/terapia , Linfócitos T Reguladores/imunologia , Animais , Infecções por Bacteroidaceae , Quimiocinas CC/metabolismo , Citocinas/metabolismo , Bases de Dados Bibliográficas , Humanos , Camundongos , Periodontite/microbiologia , Porphyromonas gingivalis , Ligante RANK/metabolismoRESUMO
Periodontitis is an inflammatory disease, in which the host immuno-inflammatory response against the dysbiotic subgingival biofilm leads to the breakdown of periodontal tissues. Most of the available treatments seem to be effective in the short-term; nevertheless, permanent periodical controls and patient compliance compromise long-term success. Different strategies have been proposed for the modulation of the host immune response as potential therapeutic tools to take a better care of most susceptible periodontitis patients, such as drug local delivery approaches. Though, maintaining an effective drug concentration for a prolonged period of time has not been achieved yet. In this context, advanced drug delivery strategies using biodegradable nanocarriers have been proposed to avoid toxicity and frequency-related problems of treatment. The versatility of distinct nanocarriers allows the improvement of their loading and release capabilities and could be potentially used for microbiological control, periodontal regeneration, and/or immunomodulation. In the present review, we revise and discuss the most frequent biodegradable nanocarrier strategies proposed for the treatment of periodontitis, including polylactic-co-glycolic acid (PLGA), chitosan, and silica-derived nanoparticles, and further suggest novel therapeutic strategies.
Assuntos
Quitosana/química , Nanopartículas , Periodontite/terapia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/químicaRESUMO
The transcription factor FOXP3 is an essential marker of the development and activation of regulatory T cells (Tregs), which are cells specialized in the regulation and normal tolerance of the immune response. In the context of chronic viral liver diseases, Tregs participate in the maintenance of infections by promoting histopathological control and favor the immune escape of viral agents by suppressing the antiviral response. Single nucleotide polymorphisms (SNPs) may influence the function of FOXP3 in a number of pathological conditions. The present study sought to evaluate the influence of SNPs in the FOXP3 gene promoter region in patients with chronic viral liver diseases. Three SNPs (-3279C>A, -2383C>T, and -924A>G) were analyzed in groups of patients with chronic hepatitis C (CHC), active chronic hepatitis B (CHB-A), inactive chronic hepatitis B (CHB-I), and a healthy control group (CG) using real-time PCR. The frequencies of the polymorphic variants were compared between groups and correlated with liver histopathological characteristics and enzyme levels [i.e., alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transpeptidase (GGT)] obtained via biopsy and from the clinical records of the participating patients, respectively. For the -2338C>T SNP, no significant differences were found in the frequencies of variants between groups or in the histological findings. Significant associations between the polymorphisms and the CHB-I group were not established. The -3279C>A SNP was associated with altered viral loads (log10) and GGT levels in CHC patients with advanced stages of inflammatory activity and liver fibrosis. The -924A>G SNP was associated with altered viral loads (log10) and liver enzyme levels among CHB-A patients with milder inflammation and fibrosis. However, the frequencies of the -3279C>A and -924A>G polymorphisms were not directly associated with the histopathological profiles of the analyzed patients. These polymorphic variants may influence hepatic function in patients with chronic viral liver diseases but are not directly associated with the establishment of the degree of inflammatory activity and liver fibrosis.
Assuntos
Fatores de Transcrição Forkhead/genética , Genótipo , Hepacivirus/fisiologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/genética , Hepatite C Crônica/genética , Fígado/metabolismo , Carga Viral/estatística & dados numéricos , Adulto , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Feminino , Fibrose , Frequência do Gene , Estudos de Associação Genética , Humanos , Desequilíbrio de Ligação , Fígado/patologia , Fígado/virologia , Masculino , Polimorfismo de Nucleotídeo Único , Fatores Sexuais , Linfócitos T Reguladores/fisiologia , gama-Glutamiltransferase/metabolismoRESUMO
The chronic inflammatory immune response triggered by the infection of the tooth root canal system results in the local upregulation of RANKL, resulting in periapical bone loss. While RANKL has a well-characterized role in the control of bone homeostasis/pathology, it can play important roles in the regulation of the immune system, although its possible immunoregulatory role in infectious inflammatory osteolytic conditions remains largely unknown. Here, we used a mouse model of infectious inflammatory periapical lesions subjected to continuous or transitory anti-RANKL inhibition, followed by the analysis of lesion outcome and multiple host response parameters. Anti-RANKL administration resulted in arrest of bone loss but interfered in the natural immunoregulation of the lesions observed in the untreated group. RANKL inhibition resulted in an unremitting proinflammatory response, persistent high proinflammatory and effector CD4 response, decreased regulatory T-cell (Treg) migration, and lower levels of Treg-related cytokines IL-10 and TGFb. Anti-RANKL blockade impaired the immunoregulatory process only in early disease stages, while the late administration of anti-RANKL did not interfere with the stablished immunoregulation. The impaired immunoregulation due to RANKL inhibition is characterized by increased delayed-type hypersensitivity in vivo and T-cell proliferation in vitro to the infecting bacteria, which mimic the effects of Treg inhibition, reinforcing a possible influence of RANKL on Treg-mediated suppressive response. The adoptive transfer of CD4+FOXp3+ Tregs to mice receiving anti-RANKL therapy restored the immunoregulatory capacity, attenuating the inflammatory response in the lesions, reestablishing normal T-cell response in vivo and in vitro, and preventing lesion relapse upon anti-RANKL therapy cessation. Therefore, while RANKL inhibition efficiently limited the periapical bone loss, it promoted an unremitting host inflammatory response by interfering with Treg activity, suggesting that this classic osteoclastogenic mediator plays a role in immunoregulation.
Assuntos
Osteólise/imunologia , Doenças Periapicais/imunologia , Ligante RANK/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Perda do Osso Alveolar/imunologia , Perda do Osso Alveolar/microbiologia , Animais , Anticorpos Monoclonais/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Expressão Gênica , Imunidade nas Mucosas , Inflamação/imunologia , Inflamação/microbiologia , Infliximab/farmacologia , Interleucina-10/imunologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteólise/microbiologia , Doenças Periapicais/microbiologia , Ligante RANK/antagonistas & inibidores , Reação em Cadeia da Polimerase em Tempo Real , Fator de Crescimento Transformador beta/imunologiaRESUMO
Regulatory T cells (Tregs) are known to control immune responses by suppressing the antigen-presenting and effector T cells. Some mechanisms adopted by Tregs in combating Mycobacterium infections have been proposed. Nevertheless, in M. leprae infection, also known as leprosy or Hansen's disease, the role of Tregs has not been completely elucidated. Using multicolor flow cytometry, we evaluated the expression of different cell surface and intracellular molecules present in Tregs from peripheral blood samples of leprosy patients. Before initiating treatment, thirteen new cases of leprosy were grouped according to the Ridley-Jopling classification in to the paucibacilary (PB) or multibacilary (MB) group. Fifteen non-infected individuals (NI) were included as control subjects. Tregs were higher in the MB group than in the NI group. Tregs also co-expressed high amounts of PD1 and PDL-1, indicating that these cells could induce apoptosis of effector cells and simultaneously prevent their own apoptosis. Our data showed that compared to the NI group, Tregs from the PB group expressed higher levels of CD95L, which may be associated with other apoptotic pathways that may decrease Tregs in these patients. Correlation analysis reinforced that PD1 and CD95L are efficient apoptosis' pathway that decreased levels of Tregs in the NI and PB groups. We also observed significant differences in cytokine expression of Tregs from the PB and MB groups. Compared to the NI group, Tregs from the MB group showed higher IL-17 expression; however, compared to the PB group, the expression of IL-10 in Tregs from the MB group was lower, suggesting inefficient control of inflammation. Therefore, we concluded that different pathways were involved in Treg-induced suppression of leprosy. Moreover, Treg-mediated regulation of inflammation via IL-10 and IL-17 expression in leprosy patients was inefficient. Thus, we propose that during M. leprae infection, Tregs may impair the immune responses elicited against this bacillus, favor bacterial replication, and aid in persistence of a disseminated multibacillary disease.
Assuntos
Células Sanguíneas/imunologia , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Apoptose , Antígeno B7-H1/metabolismo , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Fator de Transcrição Ikaros/metabolismo , Imunofenotipagem , Interleucina-10/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Masculino , Receptor de Morte Celular Programada 1/metabolismoRESUMO
A imunoterapia alérgeno-específica tem sido usada há mais de 100 anos como um tratamento de dessensibilização para doenças alérgicas, representando um método potencialmente curativo e específico. O presente estudo tem como objetivo revisar os mecanismos da imunoterapia alérgeno-específica, através de revisão bibliográfica com base em artigos publicados entre 1998 e 2016, disponíveis no banco de dados PubMed. Os mecanismos de ação da imunoterapia incluem modulação de linfócitos T e B, produção de IgG4 alérgeno-específica e redução de IgE alérgenoespecífica, migração de eosinófilos, basófilos e mastócitos nos tecidos, bem como a liberação de seus mediadores. As células T reguladoras (Treg) suprimem as células dendríticas responsáveis pela geração de células T efetoras, inibindo TH1, TH2 e TH17. As células Treg foram identificadas como peças-chave no processo de indução de tolerância periférica aos alérgenos.
Allergen-specific immunotherapy has been used for more than 100 years as a desensitizing therapy for allergic diseases, representing a potentially curative and specific method. The aim of the present study was to review the mechanisms of allergenspecific immunotherapy based on papers published between 1998 and 2016 and available in the PubMed database. The mechanisms of action of immunotherapy include modulation of T-and B-cell responses, induction of allergen-specific IgG4 and suppression of allergen-specific IgE production, migration of eosinophils, basophils, and mast cells to tissues, as well as release of their mediators. Regulatory T cells (Treg) suppress dendritic cells that support the generation of effector T cells, inhibiting TH1, TH2, and TH17 cells. Treg cells have been identified as key regulators of the induction process of peripheral allergen tolerance.
Assuntos
Humanos , Alérgenos , Linfócitos T Reguladores , Imunoterapia , Terapêutica , Basófilos , Células Dendríticas , Imunoglobulina E , Imunoglobulina G , Linfócitos B , Eosinófilos , Células Th17RESUMO
Peritoneal ascites are a distinguishable feature of patients with advanced epithelial ovarian cancer (EOC). The presence of different lymphocyte subsets has been reported in EOC-associated ascites, which also can or not contain malignant cells. The goal of this study was to analyze the functional characteristics of natural killer (NK) cells from EOC-associated ascites in terms of their expression of activating receptors and ascites' contents of lymphocyte subtypes, cytokine profile and presence of EOC cells. NK cell function was evaluated by the expression of the degranulation marker CD107a in resting and interleukin (IL)-2 stimulated NK cells from ascites and blood. Degranulation of NK cells from EOC cell-free ascites was significantly (p < 0.05) higher than all the other groups, either in their resting state or after IL-2 stimulation, suggesting a previous local stimulation. In contrast, treatment with IL-2 had no effect on NK cells from ascites with EOC cells. The amount of regulatory T cells was significantly higher in ascites with EOC cells compared to EOC cell-free ascites. Ascites with EOC cells also had higher levels of tumor necrosis factor (TNF)-α, suggesting inflammation related to the malignancy. In conclusion, the functional performance of NK cells was distinct between EOC cell-free ascites and ascites with EOC cells. The impairment of NK cell response to IL-2 in ascites with EOC cells was consistent with an immunosuppressive tumor microenvironment.
Assuntos
Ascite/imunologia , Ascite/patologia , Interleucina-2/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/metabolismo , Idoso , Biomarcadores , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Degranulação Celular/efeitos dos fármacos , Degranulação Celular/imunologia , Linhagem Celular Tumoral , Citocinas/genética , Citocinas/metabolismo , Feminino , Expressão Gênica , Humanos , Imunofenotipagem , Interleucina-2/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/imunologia , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologiaRESUMO
Glioblastoma multiforme (GBM) is a deadly cancer characterized by a pro-tumoral immune response. T-regulatory (Treg) lymphocytes suppress effector immune cells through cytokine secretion and the adenosinergic system. Ecto-5'-nucleotidase/CD73 plays a crucial role in Treg-mediated immunosuppression in the GBM microenvironment (GME). Methotrexate (MTX) is an immunosuppressive drug that can increase the extracellular concentration of adenosine. In this manuscript, C6 GBM cells were treated with 1.0 µM MTX, and ecto-5'-nucleotidase/CD73 expression and extracellular AMP metabolism were analyzed in vitro. For in vivo studies, rats with implanted GBM were treated for 10 days with MTX-loaded lipid-core nanocapsules (MTX-LNCs, 1 mg/kg/day). The activity of ectonucleotidase and the expression of NTPDase1/CD39 and ecto-5'-nucleotidase/CD73 were measured. The frequencies of T lymphocytes (CD3(+)CD4(+), CD3(+)CD8(+), and CD4(+)CD25(high)CD39(+)) were quantified. In vitro, treatment with MTX increased CD73 expression and activity in C6 cells, which is in agreement with higher levels of extracellular adenosine. In vivo, MTX-LNC treatment increased CD39 expression on CD3(+)CD8(+) lymphocytes. In addition, MTX-LNC treatment up-regulated CD73 expression in tissue isolated from GBM, a finding that is in agreement with the higher activity of this enzyme. More specifically, the treatment increased CD73 expression on CD3(+)CD4(+) and CD3(+)CD8(+) lymphocytes. Treatment with MTX-LNCs decreased the frequencies of T-cytotoxic, T-helper, and Treg lymphocytes in the GME. Although more studies are necessary to better understand the complex cross-talk mediated by supra-physiological concentrations of adenosine in the GME, these studies demonstrate that MTX treatment increases CD73 enzyme expression and AMP hydrolysis, leading to an increase in adenosine production and immunosuppressive capability.
Assuntos
5'-Nucleotidase/biossíntese , Neoplasias Encefálicas/imunologia , Glioblastoma/imunologia , Imunossupressores/farmacologia , Metotrexato/farmacologia , Linfócitos T/efeitos dos fármacos , Monofosfato de Adenosina/metabolismo , Animais , Neoplasias Encefálicas/enzimologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Glioblastoma/enzimologia , Imuno-Histoquímica , Ratos , Evasão Tumoral/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Regulação para CimaRESUMO
O HTLV-1 é o agente etiológico da leucemia /linfoma de células T do adulto (ATLL), da paraparesia espástica tropical/ mielopatia associada ao HTLV-1 (HAM/TSP) e da uveíte. Além destas, a ceratoconjutivite seca (CCS), doença multifatorial da lágrima e da superfície ocular, tem sido descrita com maior frequência em indivíduos infectados pelo HTLV-1. Assim como em outras doenças associadas, a CCS tem sido relacionada a uma elevada carga proviral. As células T regulatórias (Treg) são importantes na manutenção da homeostase do sistema imunológico e um comprometimento da imunorregulação exercido por elas pode contribuir para o ambiente inflamatório observado na CCS. Este estudo objetivou avaliar os linfócitos Treg de pacientes com CCS associada à infecção pelo HTLV-1. Foram realizados ensaios de imunofenotipagem por citometria de fluxo para avaliar a frequência de linfócitos T ativados (HLA-DR+) e de células T CD4+ e CD8+ regulatórios (FOXP3+), bem como a produção de IL-10 e TGF-β por estas células. Foram avaliados 37 pacientes infectados pelo HTLV-1 e assintomáticos para HAM/TSP, sendo 27 com diagnóstico positivo para a manifestação ocular (CCS), 10 com diagnóstico negativo (ASS), além de 17 voluntários não infectados pelo vírus (NI). As frequências de linfócitos T CD4+FOXP3+, CD8+FOXP3+, CD4+HLA-DR+ e CD8+HLA-DR+ foram significativamente maiores nos grupos CCS e ASS, quando comparados aos indivíduos não infectados. Quanto à produção das citocinas imunossupressoras, foi observada uma maior frequência de linfócitos T CD4+FOXP3+ duplo produtores de IL-10 e TGF-β no grupo CCS quando comparado ao grupo ASS. Com relação aos linfócitos CD8+FOXP3+, o grupo CCS apresentou uma maior frequência de células mono produtoras de IL-10 quando comparado ao ASS. Nossos resultados sugerem que a menor frequência de células Treg CD8+ produtoras de TGF-β em indivíduos infectados pelo HTLV-1 com CCS, pode contribuir para a intensificação da ativação celular e fisiopatologia da doença.
HTLV-1 is the causative agent of leukemia/lymphoma adult T-cell (ATLL), tropical spastic paraparesis / myelopathy associated with HTLV-1 (HAM / TSP) and uveitis. In addition, keratoconjunctivitis sicca (KCS), a multifactorial disease of the tear and of the ocular surface, has been more frequently reported in patients infected with HTLV-1. As for other HTLV-1-associated diseases, KCS has been related to a high proviral load. Regulatory T (Treg) cells are important in maintaining the homeostasis of the immune system. An impairment in the immunoregulation function of Treg may contribute to the inflammatory environment observed in the KCS. This study aimed to evaluate the Treg cells of patients with KCS associated with HTLV-1. Frequency of activated T cells (HLA-DR+) and CD4+ and CD8+ Treg cells (FOXP3+), as well as IL-10 and TGF-β production by Treg were quantified using flow cytometry. Thirty-seven HTLV-1 individuals were included (27 asymptomatic for HAM/TSP with positive diagnosis of ocular manifestation (KCS), 10 with negative diagnosis (ASS - asymptomatic). Seventeen non-infected individuals were included as controls (NI). The frequencies of CD4+ FOXP3+ T cells, CD8+FOXP3+, CD4+HLA-DR+ and CD8+HLA-DR+ were significantly higher in KCS and ASS groups when compared to non-infected individuals. As the production of immunosuppressive cytokines, a higher frequency of CD4+ FOXP3+ double producers of IL-10 and TGF-β in the KCS group was observed when compared to group ASS. Regarding the CD8+FOXP3+ lymphocytes, the KCS group had a higher frequency of mono cells producing IL-10 when compared to the ASS. Our results suggest that the lower frequency of Treg cells CD8+ TGF-β-producing in individuals infected with HTLV-1 with KCS, may contribute to the intensification of cellular activation and pathophysiology of the disease.
Assuntos
Humanos , Ceratoconjuntivite Seca/complicações , Ceratoconjuntivite Seca/diagnóstico , Ceratoconjuntivite Seca/epidemiologia , Ceratoconjuntivite Seca/patologia , Ceratoconjuntivite Seca/prevenção & controle , Ceratoconjuntivite Seca/virologia , Linfócitos/classificação , Linfócitos/sangueRESUMO
The disruption of host-microbe homeostasis at the site of periodontal disease is considered a key factor for disease initiation and progress. While the downstream mechanisms responsible for the tissue damage per se are relatively well-known (involving various patterns of immune response operating toward periodontal tissue destruction), we are only beginning to understand the complexity of host-microbe interactions in the periodontal environment. Unfortunately, most of the research has been focused on the disruption of host-microbe homeostasis instead of focusing on the factors responsible for maintaining homeostasis. In this context, regulatory T-cells (Tregs) comprise a CD4+FOXp3 +T-cell subset with a unique ability to regulate other leukocyte functions to avoid excessive immune activation and its pathological consequences. Tregs act as critical determinants of host-microbe homeostasis, as well as determinants of a balanced host response after the disruption of host-microbe homeostasis by pathogens. In periodontitis, Tregs play a protective role, with their natural recruitment being responsible for conversion of active into inactive lesions. With controlled-release technology, it is now possible to achieve a selective chemoattraction of Tregs to periodontal tissues, attenuating experimental periodontitis evolution due to the local control of inflammatory immune response and the generation of a pro-reparative environment.
Assuntos
Quimiotaxia de Leucócito/imunologia , Homeostase/imunologia , Interações Hospedeiro-Patógeno/imunologia , Periodontite/microbiologia , Linfócitos T Reguladores/imunologia , Linfócitos T CD4-Positivos/imunologia , Fatores de Transcrição Forkhead/imunologia , Humanos , Imunidade nas Mucosas/imunologia , Periodontite/imunologia , Cicatrização/imunologiaRESUMO
Autologous dendritic cells (DCs) loaded with tumor-associated antigens (TAAs) are a promising immunological tool for cancer therapy. These stimulate the antitumor response and immunological memory generation. Nevertheless, many patients remain refractory to DC approaches. Antigen (Ag) delivery to DCs is relevant to vaccine success, and antigen peptides, tumor-associated proteins, tumor cells, autologous tumor lysates, and tumor-derived mRNA have been tested as Ag sources. Recently, DCs loaded with allogeneic tumor cell lysates were used to induce a potent immunological response. This strategy provides a reproducible pool of almost all potential Ags suitable for patient use, independent of MHC haplotypes or autologous tumor tissue availability. However, optimizing autologous tumor cell lysate preparation is crucial to enhancing efficacy. This review considers the role of cancer cell-derived lysates as a relevant source of antigens and as an activating factor for ex vivo therapeutic DCs capable of responding to neoplastic cells. These promising therapies are associated with the prolonged survival of advanced cancer patients.
Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Extratos Celulares/uso terapêutico , Células Dendríticas/imunologia , Neoplasias/imunologia , Extratos Celulares/imunologia , Humanos , Memória Imunológica/imunologia , Neoplasias/prevenção & controle , Neoplasias/terapia , Linfócitos T Citotóxicos/imunologiaRESUMO
A resposta inflamatória sistêmica representa o evento patogênico central da sepse, subjazendo às manifestações clínicas e aos achados laboratoriais presentes nos enfermos. Inúmeras pesquisas têm demonstrado que os linfócitos T CD4+CD25+ - também conhecidos como células T reguladoras (Treg) - participam dos processos de desenvolvimento da sepse, em virtude de sua capacidade de suprimir a resposta imune. Com base nessas ideias, propôs-se, no presente artigo, a discussão do papel dos linfócitos Treg na sepse, com base na revisão da literatura com estratégia de busca definida (LILACS, PubMed e SciELO), tendo em vista duas abordagens principais: a participação dessas células nos processos de inflamação e imunidade, e as perspectivas de investigação fisiopatológica computacional da condição mórbida.
The systemic inflammatory response represents the core pathogenic event of sepsis, underlying clinical manifestations and laboratory findings in patients. Numerous studies have shown that CD4+CD25+ T lymphocytes, also known as regulatory T lymphocytes (Treg), participate in the development of sepsis due to their ability to suppress the immune response. The present article discusses the role of Treg lymphocytes in sepsis based on a specific search strategy (Latin American and Caribbean Health Sciences / Literatura Latino-americana e do Caribe em Ciências da Saúde - LILACS, PubMed, and Scientific Electronic Library Online - SciELO) focusing on two main topics: the participation of Treg cells in inflammation and immunity as well as perspectives in the computational physiological investigation of sepsis.
RESUMO
Las enfermedades autoinmunes son patologías de gran complejidad clínica, difícil diagnóstico y complejo tratamiento cuya etiología permanece aún desconocida pese a los múltiples avances realizados en los últimos años. En la génesis de estas enfermedades participan múltiples factores que conflyen entre sí para dar origen a cada una de las patologías autoinmunes conocidas, sean estas órgano-específicas o sistémicas. Entre estos elementos se incluyen la pérdida de los mecanismos de tolerancia, factores de susceptibilidad genética (polimorfismos HLA, genes no HLA y mecanismos epigenéticos), factores ambientales (agentes vivos de enfermedad, agentes inorgánicos, hormonas y otros) y factores inmunológicos (linfocitos reguladores, citoquinas y moléculas coestimulatorias, entre otros). La identificación de estos factores permitirá mejorar el conocimiento de los variados mecanismos que median estas complejas enfermedades, facilitando no sólo el entendimiento de su etiología sino también perfeccionar las herramientas terapéuticas para enfrentarlas.
Autoimmune diseases are pathologies of great clinical complexity, difficult diagnosis and treatment complex which etiology still remains unknowns despite the many advances made in recent years. In the genesis of these diseases involves multiple factors that converge together to give rise to each of the autoimmune diseases knows, whether organ specific or systemic. These elements include loss of tolerance mechanisms, genetic susceptibility factors (HLA polymorphisms, genes non-HLA and epigenetic mechanisms), environmental factors (living agents of disease, inorganic agents, hormones, etc.) and immunologic factors (regulators lymphocyte, cytokines, costimulatory molecules and others). Identifying these factors will improve the knowledge of the various mechanisms that mediate these complex diseases facilitating not only the understanding of the etiology but also improve the therapeutic tools to address them.
Assuntos
Humanos , Doenças Autoimunes/etiologia , Doenças Autoimunes/imunologia , Doenças Reumáticas/imunologia , Linfócitos T Reguladores/imunologia , Predisposição Genética para Doença , Tolerância Central , Tolerância ImunológicaRESUMO
OBJECTIVES: Forkhead box P3 (FoxP3) expression has been observed in human cancer cells but has not yet been reported in thyroid cells. We investigated the prognostic significance of both FoxP3 expression and intratumoral FoxP3+ lymphocyte infiltration in differentiated thyroid carcinoma cells. METHODS: We constructed a tissue microarray with 385 thyroid tissues, including 266 malignant tissues (from 253 papillary thyroid carcinomas and 13 follicular carcinomas), 114 benign lesions, and 5 normal thyroid tissues. RESULTS: We determined the expression of FoxP3 in both tumor cells and tumor-infiltrating lymphocytes using immunohistochemical techniques. Cellular expression of FoxP3 was evident in 71% of benign and 91.9% of malignant tissues. The nuclear and cytoplasmic expression patterns were quantified separately. A multivariate logistic regression analysis indicated that cytoplasmic FoxP3 expression is an independent risk factor for thyroid malignancy. Cytoplasmic FoxP3 staining was inversely correlated with patient age. Nuclear FoxP3 staining was more intense in younger patients and in tumors presenting with metastasis at diagnosis. FoxP3+ lymphocytes were more frequent in tumors smaller than 2 cm, those without extrathyroidal invasion, and in patients with concurrent chronic lymphocytic thyroiditis. CONCLUSIONS: We demonstrated FoxP3 expression in differentiated thyroid carcinoma cells and found evidence that this expression may exert an important influence on several features of tumor aggressiveness.
Assuntos
Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Carcinoma/química , Fatores de Transcrição Forkhead/análise , Linfócitos do Interstício Tumoral/química , Proteínas de Neoplasias/análise , Linfócitos T Reguladores/química , Neoplasias da Glândula Tireoide/química , Adenocarcinoma Folicular , Carcinoma Papilar , Diferenciação Celular , Carcinoma/patologia , Imuno-Histoquímica , Modelos Logísticos , Linfócitos do Interstício Tumoral/patologia , Neoplasias da Glândula Tireoide/patologia , Análise Serial de Tecidos/métodosRESUMO
O sistema imunológico humano possui um significado comum de proteção contra antígenos estranhos com potencialidade patogênica ou não, ativando uma ação coletiva e coordenada entre células e moléculas. Embora sendo um sistema benéfico, deve ser controlado para evitar que auto-antígenos sejam alvejados. Recentemente, por meio de novas técnicas, tem-se observado uma corrente de estudo para as células T CD4+CD25+ Foxp3 como células reguladoras que controlam ativamente a função de outras células imunes impedindo sua atividade e, conseqüentemente, o desenvolvimento de doenças auto-imunes, rejeição de enxerto e combate a células tumorais. Em pacientes submetidos ao transplante alogênico, os mecanismos que levam a hiporresponsividade, assim como os mecanismos que permitem uma maior sobrevida do enxerto ainda são pouco conhecidos. Este artigo aborda uma revisão da literatura sobre as células T regulatórias, vislumbrando uma nova possibilidade de terapia imunomoduladora para pacientes transplantados.
The human immune system mounts specific responses against a vast array of foreign antigens, pathogenic or otherwise, activating a coordinated action between cells and molecules. Although this is beneficial, it must be carefully controlled to ensure that normal self antigens are not targeted. Recently, with the development of new techniques, it has been observed that T CD4+CD25+Foxp3 act as regulatory cells which actively control the properties of other immune cells by suppressing their functional activity to prevent autoimmunity and transplant rejection as well as to trigger the immune system against tumor cells. In patients submitted to allogeneic transplantation, specific unresponsive mechanisms and mechanisms that induce and maintain graft tolerance are little understood. This article reviews what is currently known about these so-called regulatory T cells and discusses the potential use of these cells in transplantation immunolog.