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1.
Front Chem ; 12: 1336001, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38456183

RESUMO

SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) is the etiological agent responsible for the global outbreak of COVID-19 (Coronavirus Disease 2019). The main protease of SARS-CoV-2, Mpro, is a key enzyme that plays a vital role in mediating viral replication and transcription. In this study, a comprehensive computational approach was employed to investigate the binding affinity, selectivity, and stability of natural product candidates as potential new antivirals acting on the viral polyprotein processing mediated by SARS-CoV-2 Mpro. A library of 288 flavonoids extracted from Brazilian biodiversity was screened to select potential Mpro inhibitors. An initial filter based on Lipinski's rule of five was applied, and 204 compounds that did not violate any of the Lipinski rules were selected. The compounds were then docked into the active site of Mpro using the GOLD program, and the poses were subsequently re-scored using MM-GBSA (Molecular Mechanics Generalized Born Surface Area) binding free energy calculations performed by AmberTools23. The top five flavonoids with the best MM-GBSA binding free energy values were selected for analysis of their interactions with the active site residues of the protein. Next, we conducted a toxicity and drug-likeness analysis, and non-toxic compounds were subjected to molecular dynamics simulation and free energy calculation using the MM-PBSA (Molecular Mechanics Poisson-Boltzmann Surface Area) method. It was observed that the five selected flavonoids had lower MM-GBSA binding free energy with Mpro than the co-crystal ligand. Furthermore, these compounds also formed hydrogen bonds with two important residues, Cys145 and Glu166, in the active site of Mpro. Two compounds that passed the drug-likeness filter showed stable conformations during the molecular dynamics simulations. Among these, NuBBE_867 exhibited the best MM-PBSA binding free energy value compared to the crystallographic inhibitor. Therefore, this study suggests that NuBBE_867 could be a potential inhibitor against the main protease of SARS-CoV-2 and may be further examined to confirm our results.

2.
Sci Justice ; 63(3): 303-312, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37169455

RESUMO

Following decomposition of a human body, a variety of decomposition products, such as lipids, are released into the surrounding environment, e.g. soils. The long-lasting preservation in soils and their high diagnostic potential have been neglected in forensic research. Furthermore, little is known about the preservation, chemical transformation, or degradation of those human derived lipids in soils. To date, several studies identified various lipids such as long-chain free fatty acids and steroids in soils that contained decomposition fluids. Those lipids are preserved in soils over time and could serve as markers of human decomposition in forensic investigations, e.g. for estimating the post-mortem interval or identifying the burial location of a human body. Therefore, this review focuses on the current literature regarding fatty acid and steroid that have been detected in soils and associated with human body decomposition. After a short introduction about human decomposition processes, this review summarises fatty acid and steroid analysis applied in current case studies and studies related to taphonomic research. This review provides an overview of the available studies that have used fatty acids and steroids as identifiers of human decomposition fluid in soils in a forensic context and discusses the potential for developing this innovative field of research with direct application in a forensic context.


Assuntos
Mudanças Depois da Morte , Solo , Humanos , Corpo Humano , Ácidos Graxos/análise , Sepultamento , Patologia Legal
3.
J Drugs Dermatol ; 22(4): 375-385, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37026890

RESUMO

BACKGROUND: Interleukin (IL)-23, a member of the IL-12 family, has emerged as an important cytokine that bridges the innate and adaptive immune systems and plays a critical role in the development of a wide spectrum of immune-mediated inflammatory disorders (IMIDs). It can be considered a gatekeeper of T helper 17 (Th17) cells development and expansion that subsequently produces several mediators that promote inflammation. The inhibition of IL-23 is a potential therapeutic approach for several inflammatory diseases, such as psoriasis, psoriatic arthritis, and inflammatory bowel disease. OBJECTIVE: This work aims to address the overview of the immunobiology of IL-23 associated with some of the most frequent IMIDs and the current pipeline of its inhibition. METHODS: We conducted a narrative review elucidating data about 1) the overview of the immunobiology of IL-23 associated with immune-mediated inflammatory disorders in specific diseases, such as psoriasis, psoriatic arthritis, and inflammatory bowel disease; 2) therapeutic approaches targeting the IL-23 pathway (IL-23 inhibitor drugs approved by international agencies); and 3) novel therapeutic perspectives. The search strategy was conducted in the relevant database with terms related to the proximity to IL-23 or immuno-mediated. RESULTS AND CONCLUSIONS: Existing and emerging therapeutic biologics targeting the IL-23/IL-17 pathway are promising options to treat IMIDs while the knowledge of the pathophysiology of those conditions and the contribution of the IL23/IL-17 continues to grow. J Drugs Dermatol. 2023;22(4): doi:10.36849/JDD.7017 Citation: Galli Sanchez AP, Castanheiro da Costa A, Del Rey C, et al. The overview of the immunobiology of interleukin-23 associated with immune-mediated inflammatory disorders. A narrative review. J Drugs Dermatol. 2023;22(4):375-385. doi:10.36849/JDD.7017.


Assuntos
Artrite Psoriásica , Doenças Inflamatórias Intestinais , Psoríase , Humanos , Artrite Psoriásica/tratamento farmacológico , Interleucina-23/metabolismo , Interleucina-17/metabolismo , Agentes de Imunomodulação , Doenças Inflamatórias Intestinais/tratamento farmacológico
4.
Artigo em Inglês | MEDLINE | ID: mdl-36360755

RESUMO

To manoeuvre a complex and fragmented health care system, people need sufficient navigational health literacy (NAV-HL). The objective of this study was to validate the HLS19-NAV measurement scale applied in the European Health Literacy Population Survey 2019-2021 (HLS19). From December 2019 to January 2021, data on NAV-HL was collected in eight European countries. The HLS19-NAV was translated into seven languages and successfully applied in and validated for eight countries, where language and survey method differed. The psychometric properties of the scale were assessed using confirmatory factor analysis (CFA) and Rasch modelling. The tested CFA models sufficiently well described the observed correlation structures. In most countries, the NAV-HL data displayed acceptable fit to the unidimensional Rasch partial credit model (PCM). For some countries, some items showed poor data-model fit when tested against the PCM, and some items displayed differential item functioning for selected person factors. The HLS19-NAV demonstrated high internal consistency. To ensure content validity, the HLS19-NAV was developed based on a conceptual framework. As an estimate of discriminant validity, the Pearson correlations between the NAV-HL and general health literacy (GEN-HL) scales were computed. Concurrent predictive validity was estimated by testing whether the HLS19-NAV, like general HL measures, follows a social gradient and whether it forms a predictor of general health status as a health-related outcome of general HL. In some countries, adjustments at the item level may be beneficial.


Assuntos
Letramento em Saúde , Humanos , Reprodutibilidade dos Testes , Psicometria , Análise Fatorial , Inquéritos e Questionários
5.
Toxins (Basel) ; 14(4)2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35448887

RESUMO

Cocaine is one of the most consumed stimulants throughout the world, as official sources report. It is a naturally occurring sympathomimetic tropane alkaloid derived from the leaves of Erythroxylon coca, which has been used by South American locals for millennia. Cocaine can usually be found in two forms, cocaine hydrochloride, a white powder, or 'crack' cocaine, the free base. While the first is commonly administered by insufflation ('snorting') or intravenously, the second is adapted for inhalation (smoking). Cocaine can exert local anaesthetic action by inhibiting voltage-gated sodium channels, thus halting electrical impulse propagation; cocaine also impacts neurotransmission by hindering monoamine reuptake, particularly dopamine, from the synaptic cleft. The excess of available dopamine for postsynaptic activation mediates the pleasurable effects reported by users and contributes to the addictive potential and toxic effects of the drug. Cocaine is metabolised (mostly hepatically) into two main metabolites, ecgonine methyl ester and benzoylecgonine. Other metabolites include, for example, norcocaine and cocaethylene, both displaying pharmacological action, and the last one constituting a biomarker for co-consumption of cocaine with alcohol. This review provides a brief overview of cocaine's prevalence and patterns of use, its physical-chemical properties and methods for analysis, pharmacokinetics, pharmacodynamics, and multi-level toxicity.


Assuntos
Cocaína , Dopamina , Cocaína/análise , Cocaína/metabolismo , Cocaína/toxicidade , Etanol
6.
J Am Nutr Assoc ; 41(4): 415-423, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34156907

RESUMO

INTRODUCTION: The coronavirus disease 2019 (COVID-19) was recognized as a pandemic by the World Health Organization on March 11, 2020. As an infectious disease with no specific treatment, several measures have been established to minimize the outbreak of this disease, including social isolation. OBJECTIVE: To evaluate the behavior of adolescents during the isolation period. METHODS: This is a cross-sectional descriptive study conducted at the Adolescent Health Studies Center. Data were obtained from a questionnaire prepared on Google Forms, sent by a multiplatform instant messaging application, and analyzed using the Stata 14 software. RESULTS: A total of 208 adolescents with a mean age of 15.3 years (SD ± 1.8) answered the questionnaire, 57.7% were female. About 93.3% of adolescents said they were in isolation with a changed routine, 67.3% increased their food consumption, 86.5% were inactive, and 58.7% reported screen time over 8 h/d. There was an association between anxiety and increased food consumption (odds ratio: 3.9; CI 95% 2-7.5; p = 0.00), sleeping difficulty (odds ratio: 3.6; CI 95% 1.9-6.8; p = 0.00), and conflicting family relationship (odds ratio: 5.7; CI 95% 1.6-7.8; p = 0.01). CONCLUSION: The study revealed that social isolation due to an infectious disease was associated with several effects on the behavior and eating behavior of adolescents, which need to be acknowledged to encourage them to lead a healthy lifestyle after the COVID-19 confinement.


Assuntos
COVID-19 , Adolescente , COVID-19/epidemiologia , Estudos Transversais , Comportamento Alimentar , Feminino , Humanos , Masculino , Pandemias , SARS-CoV-2
7.
Nutr Health ; 28(2): 239-248, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33960217

RESUMO

BACKGROUND: Psoriasis is a chronic, immune-mediated skin disease. It affects skin and joints, characterized by abnormal hyperproliferation of keratinocytes. The worldwide prevalence of psoriasis ranges from 2% to 4%. Environmental factors as smoking, alcohol consumption obesity can also work as triggers. During the inflammatory process, there is an exacerbated formation of free radicals and antioxidants are required to maintain redox balance. AIM: Assess antioxidant profiles. METHODS: A cross-sectional study was conducted between August/2012 and March/2014. Sociodemographic, lifestyle, and biochemical measurements, dietary intake, serum lycopene and α-tocopherol, psoriasis severity according to Psoriasis Area and Severity Index were obtained. Comparisons between serum lycopene and α-tocopherol distributions according to variables were conducted using a one-way analysis of variance. Multiple linear regression was used to investigate factors associated with serum antioxidants. RESULTS: 81 participants (56% female, 62% non-white), 34% without psoriatic lesions, 51% diagnosed with mild psoriasis, and 15% with moderate psoriasis. Median (IQR) age of 54 (41, 62) years, 10 (4, 11) years of education, 17% smokers, 46% overweight and 25% obesity. In total, 72% did not reach the daily recommendation of fruit and vegetable intake. Serum lycopene and α-tocopherol were 0.2 (0.1-0.3) µmol/L and 22.5 (18.5-25.6) µmol/L, respectively. Only 14% presented adequate concentration of lycopene, but adequate α-tocopherol level was observed among 88%. CONCLUSIONS: Patients reported a diet low in vegetables and fruits and rich in ultra-processed foods and fatty acids. Adequate circulating α-tocopherol but low serum lycopene, was observed among patients. A linear trend was observed for lycopene according to the severity of psoriasis.


Assuntos
Psoríase , alfa-Tocoferol , Antioxidantes , Doença Crônica , Estudos Transversais , Dieta , Ingestão de Alimentos , Feminino , Humanos , Licopeno , Masculino , Obesidade , Psoríase/epidemiologia
8.
Ecotoxicology ; 31(1): 168-177, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34773558

RESUMO

The objective was to evaluate the effect of the glyphosate on Hymenaea courbaril L. A randomized block design with five replications was implemented. Each experimental unit was composed of one plant in a 5 L container. The treatments were 0 "control"; 96; 240; 480; and 960 g ha-1 "corresponding to 10, 25, 50, and 100% of the commercial dose of glyphosate recommended for Caryocar brasiliense crop, respectively". The evaluations were performed at 24 h and 60 days after application. Visual and anatomical evaluations did not change regardless of the dose, while the histochemical evaluation showed an accumulation of starch grains in leaf tissues. There was an increase in the photosynthetic rate, in the electron transport rate, and in the effective quantum yield of photosystem II at 24 h after application. At 60 days after the application of the treatments, the photosynthetic rate showed a slight decrease and the transpiratory rate showed quadratic behavior. An increase in plant height was observed up to the dose of 480 g ha-1, a linear increase in stem diameter and a decrease in the number of leaves with increasing glyphosate doses. These results show that the cuticle protected the plant, and that the little absorbed glyphosate increased photosynthesis and transpiration to favor the plants. We can conclude that the H. courbaril species is able to survive after contact with glyphosate during the evaluated time, with no visual and/or anatomical damage, showing increases in growth and physiological characteristics for the tested doses.


Assuntos
Glicina , Hymenaea , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Fotossíntese , Glifosato
9.
Pharmaceuticals (Basel) ; 14(3)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669071

RESUMO

ADB-FUBINACA and AMB-FUBINACA are two synthetic indazole-derived cannabinoid receptor agonists, up to 140- and 85-fold more potent, respectively, than trans-∆9-tetrahydrocannabinol (∆9-THC), the main psychoactive compound of cannabis. Synthesised in 2009 as a pharmaceutical drug candidate, the recreational use of ADB-FUBINACA was first reported in 2013 in Japan, with fatal cases being described in 2015. ADB-FUBINACA is one of the most apprehended and consumed synthetic cannabinoid (SC), following AMB-FUBINACA, which emerged in 2014 as a drug of abuse and has since been responsible for several intoxication and death outbreaks. Here, we critically review the physicochemical properties, detection methods, prevalence, biological effects, pharmacodynamics and pharmacokinetics of both drugs. When smoked, these SCs produce almost immediate effects (about 10 to 15 s after use) that last up to 60 min. They are rapidly and extensively metabolised, being the O-demethylated metabolite of AMB-FUBINACA, 2-(1-(4-fluorobenzyl)-1H-indazole-3-carboxamide)-3-methylbutanoic acid, the main excreted in urine, while for ADB-FUBINACA the main biomarkers are the hydroxdimethylpropyl ADB-FUBINACA, hydroxydehydrodimethylpropyl ADB-FUBINACA and hydroxylindazole ADB-FUBINACA. ADB-FUBINACA and AMB-FUBINACA display full agonism of the CB1 receptor, this being responsible for their cardiovascular and neurological effects (e.g., altered perception, agitation, anxiety, paranoia, hallucinations, loss of consciousness and memory, chest pain, hypertension, tachycardia, seizures). This review highlights the urgent requirement for additional studies on the toxicokinetic properties of AMB-FUBINACA and ADB-FUBINACA, as this is imperative to improve the methods for detecting and quantifying these drugs and to determine the best exposure markers in the various biological matrices. Furthermore, it stresses the need for clinicians and pathologists involved in the management of these intoxications to describe their findings in the scientific literature, thus assisting in the risk assessment and treatment of the harmful effects of these drugs in future medical and forensic investigations.

10.
Pharmaceuticals (Basel) ; 14(2)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546518

RESUMO

Salvia divinorum Epling and Játiva is a perennial mint from the Lamiaceae family, endemic to Mexico, predominantly from the state of Oaxaca. Due to its psychoactive properties, S. divinorum had been used for centuries by Mazatecans for divinatory, religious, and medicinal purposes. In recent years, its use for recreational purposes, especially among adolescents and young adults, has progressively increased. The main bioactive compound underlying the hallucinogenic effects, salvinorin A, is a non-nitrogenous diterpenoid with high affinity and selectivity for the k-opioid receptor. The aim of this work is to comprehensively review and discuss the toxicokinetics and toxicodynamics of S. divinorum and salvinorin A, highlighting their psychological, physiological, and toxic effects. Potential therapeutic applications and forensic aspects are also covered in this review. The leaves of S. divinorum can be chewed, drunk as an infusion, smoked, or vaporised. Absorption of salvinorin A occurs through the oral mucosa or the respiratory tract, being rapidly broken down in the gastrointestinal system to its major inactive metabolite, salvinorin B, when swallowed. Salvinorin A is rapidly distributed, with accumulation in the brain, and quickly eliminated. Its pharmacokinetic parameters parallel well with the short-lived psychoactive and physiological effects. No reports on toxicity or serious adverse outcomes were found. A variety of therapeutic applications have been proposed for S. divinorum which includes the treatment of chronic pain, gastrointestinal and mood disorders, neurological diseases, and treatment of drug dependence. Notwithstanding, there is still limited knowledge regarding the pharmacology and toxicology features of S. divinorum and salvinorin A, and this is needed due to its widespread use. Additionally, the clinical acceptance of salvinorin A has been hampered, especially due to the psychotropic side effects and misuse, turning the scientific community to the development of analogues with better pharmacological profiles.

11.
Pharmaceuticals (Basel) ; 13(11)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114119

RESUMO

Ayahuasca is a hallucinogenic botanical beverage originally used by indigenous Amazonian tribes in religious ceremonies and therapeutic practices. While ethnobotanical surveys still indicate its spiritual and medicinal uses, consumption of ayahuasca has been progressively related with a recreational purpose, particularly in Western societies. The ayahuasca aqueous concoction is typically prepared from the leaves of the N,N-dimethyltryptamine (DMT)-containing Psychotria viridis, and the stem and bark of Banisteriopsis caapi, the plant source of harmala alkaloids. Herein, the toxicokinetics and toxicodynamics of the psychoactive DMT and harmala alkaloids harmine, harmaline and tetrahydroharmine, are comprehensively covered, particularly emphasizing the psychological, physiological, and toxic effects deriving from their concomitant intake. Potential therapeutic utility, particularly in mental and psychiatric disorders, and forensic aspects of DMT and ayahuasca are also reviewed and discussed. Following administration of ayahuasca, DMT is rapidly absorbed and distributed. Harmala alkaloids act as potent inhibitors of monoamine oxidase A (MAO-A), preventing extensive first-pass degradation of DMT into 3-indole-acetic acid (3-IAA), and enabling sufficient amounts of DMT to reach the brain. DMT has affinity for a variety of serotonergic and non-serotonergic receptors, though its psychotropic effects are mainly related with the activation of serotonin receptors type 2A (5-HT2A). Mildly to rarely severe psychedelic adverse effects are reported for ayahuasca or its alkaloids individually, but abuse does not lead to dependence or tolerance. For a long time, the evidence has pointed to potential psychotherapeutic benefits in the treatment of depression, anxiety, and substance abuse disorders; and although misuse of ayahuasca has been diverting attention away from such clinical potential, research onto its therapeutic effects has now strongly resurged.

12.
Proc Natl Acad Sci U S A ; 116(20): 9969-9978, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31036644

RESUMO

Immunological memory exists so that following infection an expanded population of pathogen-specific lymphocytes can rapidly and efficiently control infection in the case of reexposure. However, in the case of CD8+ T lymphocytes, a population of unconventional CD44+CD122+ virtual memory T cells (TVM) has been described that possesses many, though not all, features of "true memory" T cells, without the requirement of first encountering cognate antigen. Here, we demonstrate a role for regulatory T cell-mediated restraint of TVM at least in part through limiting IL-15 trans-presentation by CD11b+ dendritic cells. Further, we show that keeping TVM in check ensures development of functional, antigen-specific "true" memory phenotype CD8+ T cells that can assist in pathogen control upon reexposure.


Assuntos
Memória Imunológica , Linfócitos T Reguladores/fisiologia , Animais , Linfócitos T CD8-Positivos/fisiologia , Antígeno CTLA-4/fisiologia , Células Dendríticas/fisiologia , Integrina beta1 , Interleucina-15/fisiologia , Masculino , Camundongos
15.
Sci Rep ; 7: 40720, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28094802

RESUMO

Given the rapid spread of flaviviruses such as West Nile virus (WNV) and Zika virus, it is critical that we develop a complete understanding of the key mediators of an effective anti-viral response. We previously demonstrated that WNV infection of mice deficient in mitochondrial antiviral-signaling protein (MAVS), the signaling adaptor for RNA helicases such as RIG-I, resulted in increased death and dysregulated immunity, which correlated with a failure of Treg expansion following infection. Thus, we sought to determine if intrinsic MAVS signaling is required for participation of Tregs in anti-WNV immunity. Despite evidence of increased Treg cell division, Foxp3 expression was not stably maintained after WNV infection in MAVS-deficient mice. However, intrinsic MAVS signaling was dispensable for Treg proliferation and suppressive capacity. Further, we observed generation of an effective anti-WNV immune response when Tregs lacked MAVS, thereby demonstrating that Treg detection of the presence of WNV through the MAVS signaling pathway is not required for generation of effective immunity. Together, these data suggest that while MAVS signaling has a considerable impact on Treg identity, this effect is not mediated by intrinsic MAVS signaling but rather is likely an effect of the overproduction of pro-inflammatory cytokines generated in MAVS-deficient mice after WNV infection.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Infecções por Flavivirus/imunologia , Infecções por Flavivirus/metabolismo , Flavivirus/fisiologia , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Doença Aguda , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Infecções por Flavivirus/genética , Infecções por Flavivirus/virologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Expressão Gênica , Imunofenotipagem , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Febre do Nilo Ocidental , Vírus do Nilo Ocidental
16.
Microbiology (Reading) ; 162(1): 94-99, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26490153

RESUMO

Streptococcus agalactiae (Group B Streptococcus; GBS) is an important pathogen and is associated with pneumonia, sepsis and meningitis in neonates and adults. GBS infections induce cytotoxicity of respiratory epithelial cells (A549) with generation of reactive oxygen species (ROS) and loss of mitochondrial membrane potential (ψm). The apoptosis of A549 cells by GBS was dependent on the activation of caspase-3 and caspase-9 with increased pro-apoptotic Bim and Bax molecules and decreased Bcl-2 pro-survival protein. Treatment of infected A549 cells with ROS inhibitors (diphenyleniodonium chloride or apocynin) prevented intracellular ROS production and apoptosis. Consequently, oxidative stress is included among the cellular events leading to apoptosis during GBS human invasive infections.


Assuntos
Apoptose , Células Epiteliais/citologia , Espécies Reativas de Oxigênio/metabolismo , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/fisiopatologia , Streptococcus agalactiae/fisiologia , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Humanos , Infecções Estreptocócicas/metabolismo
18.
J Immunol ; 192(2): 683-90, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24337378

RESUMO

Regulatory T cells (Tregs) are well known for their role in dampening the immune responses to self-Ags and, thereby, limiting autoimmunity. However, they also must permit immune responses to occur against foreign infectious agents. Using a mouse model of West Nile virus infection, we examined the role of Tregs in the generation of effector and memory T cell responses in the secondary lymphoid organs, as well as the infected tissues. We found that Treg numbers and activation increased in both the secondary lymphoid organs and CNS postinfection. Using Foxp3(DTR) knock-in mice, we found that Treg-deficient mice had increased Ag-driven production of IFN-γ from both CD4(+) and CD8(+) T cells in the spleen and CNS during the effector phase. In mice lacking Tregs, there were greater numbers of short-lived effector CD8(+) T cells in the spleen during the peak of the immune response, but the memory CD8(+) T cell response was impaired. Specifically, we demonstrate that Treg-dependent production of TGF-ß results in increased expression of CD103 on CD8(+) T cells, thereby allowing for a large pool of resident memory T cells to be maintained in the brain postinfection.


Assuntos
Memória Imunológica/imunologia , Linfócitos T Reguladores/imunologia , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/imunologia , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/virologia , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Cadeias alfa de Integrinas/imunologia , Cadeias alfa de Integrinas/metabolismo , Interferon gama/imunologia , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Baço/imunologia , Baço/metabolismo , Baço/virologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/virologia , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo , Febre do Nilo Ocidental/metabolismo , Febre do Nilo Ocidental/virologia
19.
Antonie Van Leeuwenhoek ; 104(6): 1125-33, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24052367

RESUMO

We explored Group B Streptococcus (GBS)-induced apoptosis in human umbilical vein endothelial cells (HUVEC) and the role of phosphoramidon, a zinc metalloprotease inhibitor, in this process. GBS 90186 strain (serotype V, a blood isolate) and concentrated supernatant (CS) were used to investigate the viability and morphological alterations in HUVEC by Trypan blue uptake, electrophoresis in 2 % agarose gel and scanning electron microscopy assays. Apoptosis before and after phosphoramidon-treatment were verified by flow cytometry using annexin V-FITC labeling. Differences were considered significant when P < 0.05 using unpaired Student's t test. GBS and CS induced HUVEC death by apoptosis (76.5 and 32 %, respectively) with an increasing pro-apoptotic Bax expression and decreasing anti-apoptotic Bcl-2 expression. Caspase-3 was activated during GBS-induced endothelial apoptosis. Phosphoramidon reduced 89.3 and 100 % of GBS and CS cell death by apoptosis, respectively. Some GBS strains may induce cell death by apoptosis with involvement of metalloproteases and signaling through the intrinsic pathway of apoptosis, which may contribute to GBS survival during sepsis of adults and neonates.


Assuntos
Apoptose , Células Endoteliais/microbiologia , Células Endoteliais/fisiologia , Glicopeptídeos/metabolismo , Metaloproteases/metabolismo , Inibidores de Proteases/metabolismo , Streptococcus agalactiae/enzimologia , Anexina A5/análise , Sobrevivência Celular , Células Cultivadas , Eletroforese , Humanos , Metaloproteases/antagonistas & inibidores , Microscopia Eletrônica , Coloração e Rotulagem/métodos , Azul Tripano/metabolismo
20.
J Immunol ; 190(6): 2720-35, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23390298

RESUMO

Recombinant adenoviral vectors (rAds) are the most potent recombinant vaccines for eliciting CD8(+) T cell-mediated immunity in humans; however, prior exposure from natural adenoviral infection can decrease such responses. In this study we show low seroreactivity in humans against simian- (sAd11, sAd16) or chimpanzee-derived (chAd3, chAd63) compared with human-derived (rAd5, rAd28, rAd35) vectors across multiple geographic regions. We then compared the magnitude, quality, phenotype, and protective capacity of CD8(+) T cell responses in mice vaccinated with rAds encoding SIV Gag. Using a dose range (1 × 10(7)-10(9) particle units), we defined a hierarchy among rAd vectors based on the magnitude and protective capacity of CD8(+) T cell responses, from most to least, as: rAd5 and chAd3, rAd28 and sAd11, chAd63, sAd16, and rAd35. Selection of rAd vector or dose could modulate the proportion and/or frequency of IFN-γ(+)TNF-α(+)IL-2(+) and KLRG1(+)CD127(-)CD8(+) T cells, but strikingly ∼30-80% of memory CD8(+) T cells coexpressed CD127 and KLRG1. To further optimize CD8(+) T cell responses, we assessed rAds as part of prime-boost regimens. Mice primed with rAds and boosted with NYVAC generated Gag-specific responses that approached ∼60% of total CD8(+) T cells at peak. Alternatively, priming with DNA or rAd28 and boosting with rAd5 or chAd3 induced robust and equivalent CD8(+) T cell responses compared with prime or boost alone. Collectively, these data provide the immunologic basis for using specific rAd vectors alone or as part of prime-boost regimens to induce CD8(+) T cells for rapid effector function or robust long-term memory, respectively.


Assuntos
Adenoviridae/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Produtos do Gene gag/imunologia , Vetores Genéticos/administração & dosagem , HIV-1/imunologia , Garantia da Qualidade dos Cuidados de Saúde , Vírus da Imunodeficiência Símia/imunologia , Adenoviridae/genética , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Modelos Animais de Doenças , Epitopos de Linfócito T/administração & dosagem , Epitopos de Linfócito T/uso terapêutico , Produtos do Gene gag/administração & dosagem , Produtos do Gene gag/uso terapêutico , Vetores Genéticos/imunologia , Vetores Genéticos/uso terapêutico , Células HEK293 , HIV-1/genética , Humanos , Imunofenotipagem/métodos , Imunofenotipagem/normas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pan troglodytes , Garantia da Qualidade dos Cuidados de Saúde/normas , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , Vírus da Imunodeficiência Símia/genética
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