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Pyroptosis cell death in recent thymus emigrants (RTE) CD4+ T lymphocytes plays an important role on HIV-1 infection as a cause of CD4+ T cell depletion, being influenced by several factors, among them, the sex. Thus, the aim of this study was evaluated pyroptosis levels in RTE CD4+ T lymphocytes of individuals under antiretroviral therapy (ART) stratified by sex. Thirty-seven ART-treated HIV-positive patients (22 females and 15 males) and 12 (seven females and five males) clinically health subjects were recruited. Analysis by flow-cytometry of RTE CD4+ cells (CD4+ CD31+ /fluorescent-labeled inhibitors of caspases-Caspase-1+) were performed. Clinical and sociodemographic aspects were also evaluated from medical records. We observed statistically higher levels of pyroptosis RTE CD4+ T cells in male individuals (69.3%) compared with female group (39.1%) (P = 0.0356). Pre- and post-treatment CD4+ T cell counts were also higher in women than men (P = 0.004 and P = 0.012, respectively). Our data provides important evidence of the sex as a potential predictor of immunological reconstitution in ART-treated individuals.
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Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/patologia , Infecções por HIV/patologia , HIV-1/imunologia , Piroptose , Timo/patologia , Adulto , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , Humanos , Masculino , Fatores Sexuais , Timo/efeitos dos fármacos , Timo/imunologiaRESUMO
The scientific community still faces the challenge of developing strategies to cure HIV-1. One of these pursued strategies is the development of immunotherapeutic vaccines based on dendritic cells (DCs), pulsed with the virus, that aim to boost HIV-1 specific immune response. We aimed to review DCs-based therapeutic vaccines reports and critically assess evidence to gain insights for the improvement of these strategies. We performed a systematic review, followed by meta-analysis and meta-regression, of clinical trial reports. Twelve studies were selected for meta-analysis. The experimental vaccines had low efficiency, with an overall success rate around 38% (95% confidence interval = 26.7%-51.3%). Protocols differed according to antigen choice, DC culture method, and doses, although multivariate analysis did not show an influence of any of them on overall success rate. The DC-based vaccines elicited at least some immunogenicity, that was sometimes associated with plasmatic viral load transient control. The protocols included both naïve and antiretroviral therapy (ART)-experienced individuals, and used different criteria for assessing vaccine efficacy. Although the vaccines did not work as expected, they are proof of concept that immune responses can be boosted against HIV-1. Protocol standardization and use of auxiliary approaches, such as latent HIV-1 reservoir activation and patient genomics are paramount for fine-tuning future HIV-1 cure strategies.
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Vacinas contra a AIDS/uso terapêutico , Células Dendríticas/imunologia , Infecções por HIV/tratamento farmacológico , Imunoterapia/métodos , Ensaios Clínicos como Assunto , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , HumanosRESUMO
Tuberculosis (TB) caused by Mycobacterium tuberculosis, is major cause of morbidity and mortality worldwide. So far, many candidate genes have been investigated for their possible association with TB. Dendritic cell-specific intercellular adhesion molecule 3 (ICAM-3) grabbing non-integrin (DC-SIGN) and Liver/lymph node-specific intercellular adhesion molecule-grabbing non-integrin (L-SIGN), encoded by CD209 and CD209L genes respectively, are known for binding to M. tuberculosis on human dendritic cells and macrophages. We screened 4 single nucleotide polymorphisms (SNPs) in the promoter region of CD209, namely -939G>A (rs735240), -871A>G (rs735239), -336A>G (rs4804803) and -139G>A (rs2287886) and tandem repeat polymorphisms in exon 4 of CD209 and CD209L genes looking for association with TB in a Northeastern Brazilian population (295 subjects, 131 TB patients and 164 healthy controls). The -139G>A and -939G>A SNPs were associated with susceptibility to TB, and in particular with pulmonary and extra-pulmonary forms respectively. The -871A>G and -336A>G SNPs were associated, the first with protection to both pulmonary and extra-pulmonary TB, the latter only with the pulmonary form. An association between GGAG haplotype and protection to TB infection was also found. Also tandem repeat polymorphism in CD209L exon 4 was associated with TB infection. This study provides evidence of an association between CD209 and CD209L polymorphisms and TB development in a Brazilian population, suggesting that variations in these genes may influence the protection and susceptibility to infection caused by M. tuberculosis.
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Moléculas de Adesão Celular/genética , Predisposição Genética para Doença , Lectinas Tipo C/genética , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/genética , Tuberculose/genética , Adulto , Alelos , Brasil/epidemiologia , Estudos de Casos e Controles , Moléculas de Adesão Celular/metabolismo , Células Dendríticas/metabolismo , Feminino , Haplótipos , Humanos , Lectinas Tipo C/metabolismo , Masculino , Mycobacterium tuberculosis , Regiões Promotoras Genéticas , Receptores de Superfície Celular/metabolismo , Adulto JovemRESUMO
Inter-individual heterogeneity in the response to human T-lymphotropic virus 1 (HTLV-1) infection has been partially attributed to host genetic background. The antiviral activity of the inflammasome cytoplasmic complex recognises viral molecular patterns and regulates immune responses via the activation of interleukin (IL)-1 family (IL-1, IL-18 and IL-33) members. The association between polymorphisms in the inflammasome receptors NLRP1 and NLRP3 and HTLV-1 infection was evaluated in a northeastern Brazilian population (84 HTLV-1 carriers and 155 healthy controls). NLRP3 rs10754558 G/G was associated with protection against HTLV-1 infection (p = 0.012; odds ratio = 0.37). rs10754558 affects NLRP3 mRNA stability; therefore, our results suggest that higher NLRP3 expression may augment first-line defences, leading to the effective protection against HTLV-1 infection.
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Proteínas de Transporte/genética , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Brasil , Proteínas de Transporte/metabolismo , Feminino , Predisposição Genética para Doença , Infecções por HTLV-I/genética , Humanos , Inflamassomos/imunologia , Interleucina-1/metabolismo , Masculino , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fatores de ProteçãoRESUMO
The mechanisms underlying unsatisfactory immune reconstitution in HIV-1 positive patients under ART have not been fully elucidated, even after years of investigation. Thus, this study aimed to assess the correlation between age and thymic production profile, and its influence on inadequate immunological recovery. Here, 44 ART-treated patients with undetectable plasma HIV-1 load (<40 copies/mL) were classified as 31 immunological responders (IR) and 13 immunological non-responders (INR), according to their CD4+ T-cell count after 18 months of ART. The thymic function was assessed by identifying recent thymic emigrants (RTEs) CD4+ T cells (CD4+/CD45RA+CD31+) in PBMCs using flow cytometry. Clinical data were also analyzed from medical records. The INR group showed a higher age at ART initiation (41 ± 3.0) compared to the IR (33.7 ± 2.1) group (p = 0.041). Evaluating RTE CD4+ T-cells, we observed a lower percentage in the INR group (19.5 ± 6.3) compared to the IR group (29.9 ± 11.5) (p = 0.012). There was a strong negative correlation between age at ART initiation and RTE CD4+ T-cells in INRs (r = -0.784, p = 0.004). Our study has highlighted the thymic insufficiency and aging-related immunosenescence with unsatisfactory immunological recovery during ART in HIV-1 positive patients.
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Variations in genes involved in the immune response pathways may influence the interaction between viruses (such as Human T-lymphotropic virus, HTLV-1) and the host. The mannose binding lectin (MBL) and its associated serine protease type 2 (MASP-2) promote the activation of the lectin pathway of the complement system. As the interaction of complement system with HTLV-1 is not well understood, the MBL2 promoter/exon 1 polymorphisms and a MASP2 missense polymorphism were examined in a Northeast Brazilian population, looking for a possible relationship between these variations and the susceptibility to HTLV-1 infection. The present study describes an association between a polymorphism in the MASP2 gene and susceptibility to HTLV-1 infection, and provides further evidence of an association between the MBL2 gene and HTLV-1 infection. These findings suggest an important role of the complement system activation, via the lectin pathway, in the susceptibility to HTLV-1 infection.
Assuntos
Predisposição Genética para Doença , Infecções por HTLV-I/genética , Infecções por HTLV-I/imunologia , Lectina de Ligação a Manose/genética , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Polimorfismo Genético , Adulto , Brasil , Proteínas do Sistema Complemento/imunologia , Éxons , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Regiões Promotoras Genéticas , Adulto JovemRESUMO
Mother-to-children transmission (MTCT) is the main infection route for HIV-1 in children, and may occur during pregnancy, delivery, and/or postpartum. It is a multifactorial phenomenon, where genetic variants play an important role. This study aims at analyzing the influence of clinical epidemiological characteristics and a variant (rs12252) in interferon-induced transmembrane protein 3 (IFITM-3), a gene encoding an important viral restriction factor, on the susceptibility to HIV-1 mother-to-children transmission (MTCT). A case-control study was performed on 209 HIV-1-infected mothers and their exposed infected (87) and uninfected (122) children from Pernambuco, Brazil. Clinical-epidemiological characteristics are significantly associated with MTCT susceptibility. Transmitter mothers have a significantly lower age at delivery, late diagnosis, deficiency in ART use (pregnancy and delivery), and detectable viral load in the third trimester of pregnancy compared with non-transmitter mothers. Infected children show late diagnosis, vaginal delivery frequency, and tend to breastfeed, differing significantly from uninfected children. The IFITM-3 rs12252-C allele and TC/CC genotypes (dominant model) are significantly more frequent among infected than uninfected children, but the statistical significance does not remain when adjusted for clinical factors. No significant differences are observed between transmitter and non-transmitter mothers in relation to the IFITM-3 variant.
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Decades of studies in antiretroviral therapy (ART) have passed, and the mechanisms that determine impaired immunological recovery in HIV-positive patients receiving ART have not been completely elucidated yet. Thus, T-lymphocytes immunophenotyping and cytokines levels were analyzed in 44 ART-treated HIV-positive patients who had a prolonged undetectable plasma viral load. The patients were classified as immunological non-responders (INR = 13) and immunological responders (IR = 31), according to their CD4+ T cell levels. Evaluating pre-CD4+ levels, we observed a statistically significant trend between lower CD4+ T cell levels and INR status (Z = 3.486, p < 0.001), and during 18 months of ART, the CD4+ T cell levels maintained statistical differences between the INR and IR groups (WTS = 37.252, p < 0.001). Furthermore, the INRs were associated with an elevated age at ART start; a lower pre-treatment CD4+ T cell count and a percentage that remained low even after 18 months of ART; lower levels of recent thymic emigrant (RTE) CD4+ T cell (CD45RA + CD31+) and a naïve CD4+ T cell (CD45RA + CD62L+); higher levels of central memory CD4+ T cells (CD45RA-CD62L+); and higher immune activation by CD4+ expressing HLA-DR+ or both (HLA-DR+ and CD38+) when compared with IRs. Our study demonstrates that thymic exhaustion and increased immune activation are two mechanisms substantially implicated in the impaired immune recovery of ART-treated HIV patients.
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Infecções por HIV , Timo , Humanos , Infecções por HIV/tratamento farmacológico , Linfócitos T CD4-Positivos , Citocinas , ImunofenotipagemRESUMO
HIV-1 infection elicits a complex dynamic of the expression various host genes. High throughput sequencing added an expressive amount of information regarding HIV-1 infections and pathogenesis. RNA sequencing (RNA-Seq) is currently the tool of choice to investigate gene expression in a several range of experimental setting. This study aims at performing a meta-analysis of RNA-Seq expression profiles in samples of HIV-1 infected CD4+ T cells compared to uninfected cells to assess consistently differentially expressed genes in the context of HIV-1 infection. We selected two studies (22 samples: 15 experimentally infected and 7 mock-infected). We found 208 differentially expressed genes in infected cells when compared to uninfected/mock-infected cells. This result had moderate overlap when compared to previous studies of HIV-1 infection transcriptomics, but we identified 64 genes already known to interact with HIV-1 according to the HIV-1 Human Interaction Database. A gene ontology (GO) analysis revealed enrichment of several pathways involved in immune response, cell adhesion, cell migration, inflammation, apoptosis, Wnt, Notch and ERK/MAPK signaling.
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Linfócitos T CD4-Positivos/metabolismo , Infecções por HIV/virologia , HIV-1/fisiologia , Transcriptoma , Linfócitos T CD4-Positivos/virologia , Perfilação da Expressão Gênica , Ontologia Genética , Infecções por HIV/genética , Infecções por HIV/metabolismo , Interações Hospedeiro-Patógeno , HumanosRESUMO
Despite more than three decades of studies and advances in combination antiretroviral therapy (cART) against human immunodeficiency virus (HIV), the mechanisms that precisely determine immune reconstitution failure have not been completely elucidated yet. Thus, this study aimed to investigate the thymic function, immune activation, and cell death by pyroptosis and apoptosis in virologically suppressed HIV-positive patients receiving cART. Immunophenotyping analyses were performed in 57 cART-treated HIV-infected patients with undetectable plasma viral load, who were classified as immunological nonresponders (INR = 29) and immunologic responders (IR = 28). Sociodemographic and clinical data were also assessed from medical records. Twelve healthy volunteers were also included in this study. The INR showed lower pretreatment CD4+ T cell count that remained low even after 1 yr of treatment, lower CD4/CD8 ratio, lower percentage of recent thymic emigrant (RTE) CD4+ T cell (CD45RA+CD31+) and naïve CD4+ T cell (CD45RA+CD62L+), higher levels of effector memory CD4+ T cells (CD45RA-CD62L-), and higher pyroptosis levels of RTE CD4+ T cells (CD31+FLICA-Caspase1+) when compared with IR. Our findings indicate that reduced thymic function and RTE CD4+ T cell death by pyroptosis are the major mechanisms of immunological recovery failure in HIV-infected patients receiving cART.
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Terapia Antirretroviral de Alta Atividade/efeitos adversos , Linfócitos T CD4-Positivos/patologia , Infecções por HIV/imunologia , HIV-1/imunologia , Piroptose , Timo/imunologia , Adulto , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Imunofenotipagem , Masculino , Timo/efeitos dos fármacos , Timo/virologia , Falha de Tratamento , Carga ViralRESUMO
This study was performed to assess the association of CCR5Δ32 and SDF1-3'A polymorphisms with immunological recovery failure and to investigate the influence of sociodemographic and clinical data on immune reconstitution in human immunodeficiency virus (HIV)-positive patients during antiretroviral therapy (ART). Two hundred and forty-eight HIV-positive patients under ART with undetectable plasma viral load (<40 copies/mL) were enrolled in this study and classified into two groups according to their CD4+ T-cell count changes: immunological responders (CD4+ T-cell count gain ≥ 200/µL or ≥ 30% compared with baseline) and immunological non-responders (CD4+ T-cell count gain < 200/µL or < 30% compared with baseline). DNA extraction was performed followed by CCR5Δ32 and SDF1-3'A genotyping. Sociodemographic and clinical data were evaluated from medical records. The logistic regression model showed that heterozygosity for CCR5Δ32 allele and lower pre-treatment CD4+ T-cell count (<500 cells/µL) were statistically associated with immunological recovery failure (OR = 5.873, 95%CI = 1.204-28.633, P = 0.028 and OR = 10.00, 95%CI = 3.224-31.016, P = 0.028, respectively). No association of SDF1-3'A polymorphism with immune reconstitution failure was found. Additionally, we observed that there was a statistically significant difference between lower CD4+ T-cell count and INR status than the IR group (Z = 4.687, P < 0.001). Our results demonstrated, through a logistic regression model, that CCR5Δ32 polymorphism and pre-treatment CD4+ T-cell count have significant influence on immune reconstitution of HIV-positive patients during ART. These findings highlight some immunological factors associated with poor CD4+ T-lymphocytes recovery, which affect immune response level of ART-treated HIV-positive patients.
Assuntos
Quimiocina CXCL12/genética , Estudos de Associação Genética , Infecções por HIV/genética , Receptores CCR5/genética , Adulto , Alelos , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Feminino , Predisposição Genética para Doença , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Heterozigoto , Humanos , Masculino , Receptores CCR5/imunologia , Carga Viral/efeitos dos fármacos , Carga Viral/genética , Carga Viral/imunologiaRESUMO
OBJECTIVES: Neuropsychiatric adverse effects (NPAE) related to efavirenz, mainly dizziness, is detrimental to human immunodeficiency virus (HIV) treatment. Our study aims at evaluating if zidovudine use potentiates the risk of dizziness related to efavirenz when used together and whether there are significant differences in over time distribution of this NPAE and others relatively frequents regarding efavirenz regimen without zidovudine. METHODS: Human immunodeficiency virus-infected patients under efavirenz-containing different therapy were enrolled. A retrospective analysis of official medical records was accomplished to collect clinical data regarding NPAE occurrence and severity. Univariate statistic and statistical model based on survival analyses were performed. KEY FINDINGS: One hundred sixty-two patients were included, of these seventy-seven (47.5%) had NPAE reported, such as dizziness (more frequent), depression and insomnia. Univariate statistical analysis demonstrated that the combined use of efavirenz with zidovudine increased the NPAE risk (OR: 2.5; P-value: 0.008), mainly dizziness risk (OR: 3.5; P-value: 0.009) and survival analysis showed that such combination is associated with dizziness occurrence faster (HR: 2.9; P-value: 0.02). CONCLUSIONS: The results may contribute to clarify the dizziness occurrence dynamics in therapy with efavirenz and zidovudine by identifying susceptibilities and assisting in the choice of combined antiretroviral therapy.
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Alcinos/efeitos adversos , Fármacos Anti-HIV/efeitos adversos , Benzoxazinas/efeitos adversos , Ciclopropanos/efeitos adversos , Tontura/induzido quimicamente , Infecções por HIV/tratamento farmacológico , Inibidores da Transcriptase Reversa/efeitos adversos , Zidovudina/efeitos adversos , Adulto , Brasil , Depressão/induzido quimicamente , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Análise de Sobrevida , Fatores de TempoRESUMO
Recent developments in molecular methods have revolutionized the detection and characterization of microorganisms in a broad range of medical diagnostic fields, including virology, mycology, parasitology, microbiology and dentistry. Among these methods, Polymerase Chain Reaction (PCR) has generated great benefits and allowed scientific advancements. PCR is an excellent technique for the rapid detection of pathogens, including those difficult to culture. Along with conventional PCR techniques, Real-Time PCR has emerged as a technological innovation and is playing an ever-increasing role in clinical diagnostics and research laboratories. Due to its capacity to generate both qualitative and quantitative results, Real-Time PCR is considered a fast and accurate platform. The aim of the present literature review is to explore the clinical usefulness and potential of both conventional PCR and Real-Time PCR assays in diverse medical fields, addressing its main uses and advances.
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BACKGROUND: Pyroptosis has been reported to be critical in human immunodeficiency virus type 1 (HIV-1) pathogenesis and acquired immunodeficiency syndrome (AIDS) progression. Even after achieving viral suppression to undetectable levels during antiretroviral therapy (ART), exacerbated CD4+ T-cell death by pyroptosis has been suggested as one of the main causes of immunological non-response. Thus, variants in genes of pyroptosis pathway were studied in individuals with poor CD4+ T-cell reconstitution under antiretroviral therapy against HIV-1. METHODS: 248 virologically suppressed ART-treated patients, 126 immunological non-responders (INR) and 122 immunological responders (IR) were recruited. Genotyping was performed using TaqMan probe-based realtime PCR platform. Genotype-guided flow cytometry analysis with general and recent thymic emigrant (RTE) CD4+ T-cells in pyroptosis was performed based on associated polymorphisms. RESULTS: Both IL18 rs187238 G allele and GG genotype were associated as protection factors against poor CD4+ T-cell recovery (ORâ¯=â¯0.22; 95%CIâ¯=â¯0.50-0.77; Pâ¯=â¯.010 and ORâ¯=â¯0.58; 95%CIâ¯=â¯0.36-0.93; Pâ¯=â¯.022, respectively). It was demonstrated a statistical association between IL18 rs187238 genotypes of ART-treated patients and death by Caspase-1 levels (Pâ¯=â¯.020). The GG genotype showed lower pyroptotic RTE CD4+ T-lymphocytes levels in the ART-treated groups comparing with CC (Pâ¯=â¯.029) and CG (Pâ¯=â¯.018) genotypes, suggesting that the G allele presence may be related to a lower IL-18 production and thus reduced dead CD4+ T-cells levels by Caspase-1. CONCLUSION: We observed that IL18 G variant allele and genotype were associated with a better immunological response, which may influence on immunological recovery of HIV-positive patients receiving antiretroviral therapy, and low Caspase-1 activity levels was observed on GG genotype when compared CC genotypes.
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Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Infecções por HIV/etiologia , Interleucina-18/genética , Polimorfismo Genético , Alelos , Terapia Antirretroviral de Alta Atividade , Suscetibilidade a Doenças , Genótipo , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Soropositividade para HIV , Humanos , Imunofenotipagem , Razão de Chances , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Carga ViralRESUMO
BACKGROUND: Lopinavir and Ritonavir (LPV/r) treatment is widely used to prevent HIV mother-to-child transmission. Nevertheless, studies related to the impact of these compounds on patients, in particular in the foetus and newborns, are strictly required due to the controversial findings reported in the literature concerning possible neurologic side effects following the administration of these drugs. OBJECTIVES: In our study, we evaluated the impact of LPV/r treatment on the human glioblastoma U- 87 MG cell line. METHODS: In order to evaluate the influence of Lopinavir and Ritonavir in terms of oxidative stress (ROS production), mitochondrial morphology and apoptotic cell death, the latter either in the presence or in the absence of caspase-3 and -9 inhibitors, we treated U-87 MG with increasing doses (0.1-1-10-25-50 µM) of Lopinavir and Ritonavir for 24h, either in single formulation or in combination. ROS production was measured by flow cytometry using H2DCFDA dye, mitochondrial morphology was evaluated using MitoRed dye and apoptotic cell death was monitored by flow cytometry using Annexin V-FITC and Propidium Iodide. RESULTS: We observed that co-treatment with Lopinavir and Ritonavir (25 and 50 µM) promoted a significant increase in ROS production, caused mitochondrial network damage and induced apoptosis in a caspase-independent manner. CONCLUSION: Based on our findings, concordant with others reported in the literature, we hypothesize that LPV/r treatment could not be entirely free from side effects, being aware of the need of validation in in vivo models, necessary to confirm our results.
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Apoptose/efeitos dos fármacos , Caspases/metabolismo , Glioblastoma/metabolismo , Lopinavir/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ritonavir/farmacologia , Linhagem Celular Tumoral , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
MicroRNAs (miRNAs) are single-stranded sequences of non-coding RNA with approximately 22 nucleotides that act posttranscriptionally on gene expression. miRNAs are important gene regulators in physiological contexts, but they also impact the pathogenesis of various diseases. The role of miRNAs in viral infections has been explored by different authors in both population-based as well as in functional studies. However, the effect of miRNA polymorphisms on the susceptibility to viral infections and on the clinical course of these diseases is still an emerging topic. Thus, this review will compile and organize the findings described in studies that evaluated the effects of genetic variations on miRNA genes and on their binding sites, in the context of human viral diseases. In addition to discussing the basic aspects of miRNAs biology, we will cover the studies that investigated miRNA polymorphisms in infections caused by hepatitis B virus, hepatitis C virus, human immunodeficiency virus, Epstein-Barr virus, and human papillomavirus. Finally, emerging topics concerning the importance of miRNA genetic variants will be presented, focusing on the context of viral infectious diseases.
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BACKGROUND: Host restriction factors are cellular proteins able to diminish or block viral replication in a cell-specific way. OBJECTIVE AND METHOD: We evaluated the distribution of single nucleotide polymorphisms (SNPs) in APOBEC3G (rs3736685, rs2294367) and CUL5 (rs7117111, rs7103534, rs11212495) genes, among 264 HIV-1 infected (HIV-1+) and 259 unexposed- uninfected individuals from Northeast Brazil, looking for a possible association with susceptibility to HIV-1 infection, viral load during treatment, CD4+ T cell count and therapeutic success of the antiretroviral treatment. RESULTS: The rs11212495 CUL5 G allele and the CUL5 rs7103534-rs7117111 CG haplotype were more frequent among unexposed-uninfected than in HIV-1+ individuals, suggesting an association with a lower HIV-1 infection susceptibility. The APOBEC3G rs2294367 G/C genotype correlated with delayed viral load suppression. Our results showed a great heterogeneity in relation to the literature findings, possibly due to ethnic differences among the studied populations, sample size used in the studies and, also, to the type of controls, i.e. in our study used unexposed-uninfected rather than exposed-uninfected individuals (rare and considered gold standard for susceptibility studies). CONCLUSION: Our findings report genetic variants possibly associated with susceptibility to HIV-1 infection (CUL5 rs11212495, rs7103534, rs7117111) and partial viral load control (APOBEC3G rs2294367). Replica studies performed on higher number of subjects are envisaged to confirm our results.
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Desaminase APOBEC-3G/genética , Antirretrovirais/uso terapêutico , Proteínas Culina/genética , Predisposição Genética para Doença , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Adulto , Brasil , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/patologia , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral , Adulto JovemRESUMO
ß-Defensin-1, an antimicrobial peptide encoded by the DEFB1 gene, is known to play an important role in lung mucosal immunity. In our association study we analyzed three DEFB1 functional polymorphisms -52G>A (rs1799946), -44C>G (rs1800972) and -20G>A (rs11362) in 92 tuberculosis patients and 286 healthy controls, both from Northeast Brazil: no association was found between the studied DEFB1 polymorphisms and the disease. However we cannot exclude that this lack of association could be due to the low number of subjects analyzed, as suggested by the low statistical power achieved for the three analyzed SNPs (values between 0.16 and 0.50).
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Polimorfismo de Nucleotídeo Único , Tuberculose/genética , beta-Defensinas/genética , Adulto , Idoso , Sequência de Bases , Brasil/epidemiologia , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Tuberculose/epidemiologia , Adulto JovemRESUMO
Humans show heterogeneity in vulnerability to HIV-1 infection, partially under control of genes involved in host immunity and virus replication. TRIM5α protein has restriction activity against replication of many retroviruses. Human TRIM5 gene single nucleotide polymorphisms have been reported as involved in susceptibility to HIV-1 infection. We recruited 213 HIV-1-positive patients and 234 healthy uninfected controls from Northeast Brazil; two non-synonymous variants at exon 2, rs3740996 (H43Y) and rs10838525 (R136Q), and one regulatory polymorphism (rs16934386) at 5'UTR region of TRIM5 were analyzed. The R136Q variation presented significant differences between HIV-1-positive patients and healthy controls. The 136Q allele and the 136QQ genotype were more frequent in healthy controls (32.7 and 10.2 %, respectively) than in HIV-1-positive patients (136Q allele: 24.4 %; OR 0.66; CI 95 % 0.49-0.90; p value = 0.008/136QQ genotype: 4.2 %; OR 0.33; CI 95 % 0.13-0.79, p = 0.008) also after adjusting for age and sex. We also stratified our findings according to the presence of CCR5Δ32 variation, but the results remained the same. We observed that rs10838525 (R136Q) and rs3740996 (H43Y) were in linkage disequilibrium (D' = 0.71), forming four possible haplotypes. The H43-136Q haplotype was significantly more frequent in healthy controls (28.2 %) than in HIV-positive patients (21.4 %; OR 0.69; CI 95 % 0.50-0.96; p = 0.022). An increased frequency of allele (136Q) and genotype (136QQ) of the non-synonymous rs10838525 (R136Q) variant and the haplotype (43H-136Q) was observed among healthy controls individuals. Being aware of the limitation of this study (unavailability of exposed but uninfected individuals), we hypothesize a potential role for TRIM5 variations in the protection against HIV-1 infection.