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1.
Int J Mol Sci ; 25(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38791357

RESUMO

The lung is prone to infections from respiratory viruses such as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). A challenge in combating these infections is the difficulty in targeting antiviral activity directly at the lung mucosal tract. Boosting the capability of the respiratory mucosa to trigger a potent immune response at the onset of infection could serve as a potential strategy for managing respiratory infections. This study focused on screening immunomodulators to enhance innate immune response in lung epithelial and immune cell models. Through testing various subfamilies and pathways of pattern recognition receptors (PRRs), the nucleotide-binding and oligomerization domain (NOD)-like receptor (NLR) family was found to selectively activate innate immunity in lung epithelial cells. Activation of NOD1 and dual NOD1/2 by the agonists TriDAP and M-TriDAP, respectively, increased the number of IL-8+ cells by engaging the NF-κB and interferon response pathways. Lung epithelial cells showed a stronger response to NOD1 and dual NOD1/2 agonists compared to control. Interestingly, a less-pronounced response to NOD1 agonists was noted in PBMCs, indicating a tissue-specific effect of NOD1 in lung epithelial cells without inducing widespread systemic activation. The specificity of the NOD agonist pathway was confirmed through gene silencing of NOD1 (siRNA) and selective NOD1 and dual NOD1/2 inhibitors in lung epithelial cells. Ultimately, activation induced by NOD1 and dual NOD1/2 agonists created an antiviral environment that hindered SARS-CoV-2 replication in vitro in lung epithelial cells.


Assuntos
COVID-19 , Células Epiteliais , Pulmão , Proteína Adaptadora de Sinalização NOD1 , SARS-CoV-2 , Humanos , Células A549 , Antivirais/farmacologia , COVID-19/imunologia , COVID-19/virologia , Tratamento Farmacológico da COVID-19 , Ácido Diaminopimélico/análogos & derivados , Ácido Diaminopimélico/farmacologia , Células Epiteliais/virologia , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Imunidade Inata/efeitos dos fármacos , Interleucina-8/metabolismo , Pulmão/imunologia , Pulmão/virologia , Pulmão/metabolismo , NF-kappa B/metabolismo , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Adaptadora de Sinalização NOD1/agonistas , Proteína Adaptadora de Sinalização NOD2/agonistas , Proteína Adaptadora de Sinalização NOD2/metabolismo , SARS-CoV-2/fisiologia , SARS-CoV-2/imunologia , Transdução de Sinais/efeitos dos fármacos
2.
J Viral Hepat ; 30(1): 56-63, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36197907

RESUMO

To achieve WHO's goal of eliminating hepatitis C virus (HCV), innovative strategies must be designed to diagnose and treat more patients. Therefore, we aimed to describe an implementation strategy to identify patients with HCV who were lost to follow-up (LTFU) and offer them re-linkage to HCV care. We conducted an implementation study utilizing a strategy to contact patients with HCV who were not under regular follow-up in 13 countries from Latin America. Patients with HCV were identified by the international classification of diseases (ICD-9/10) or equivalent. Medical records were then reviewed to confirm the diagnosis of chronic HCV infection defined by anti-HCV+ and detectable HCV-RNA. Identified patients who were not under follow-up by a liver specialist were contacted by telephone or email, and offered a medical reevaluation. A total of 10,364 patients were classified to have HCV. After reviewing their medical charts, 1349 (13%) had undetectable HCV-RNA or were wrongly coded. Overall, 9015 (86.9%) individuals were identified with chronic HCV infection. A total of 5096 (56.5%) patients were under routine HCV care and 3919 (43.5%) had been LTFU. We were able to contact 1617 (41.3%) of the 3919 patients who were LTFU at the primary medical institution, of which 427 (26.4%) were cured at a different institutions or were dead. Of the remaining patients, 906 (76.1%) were candidates for retrieval. In our cohort, about one out of four patients with chronic HCV who were LTFU were candidates to receive treatment. This strategy has the potential to be effective, accessible and significantly impacts on the HCV care cascade.


Assuntos
Hepatite C Crônica , Hepatite C , Humanos , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , América Latina/epidemiologia , Perda de Seguimento , Hepacivirus/genética , Organização Mundial da Saúde
3.
J Transl Med ; 13: 230, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26183947

RESUMO

BACKGROUND: High levels of ex vivo CD4 T-cell death and the accumulation of highly differentiated and/or immunosenescent T cells have been associated with poor CD4 T-cell recovery in treated HIV-infected individuals. However, the relationship between cell death and T-cell differentiation is still unclear. METHODS: We have analyzed cell death, immunosenescence and differentiation parameters in HAART-treated subjects (VL <50 copies/mL for more than 2 years) with CD4 T-cell count <350 cells/µL (immunodiscordant, n = 23) or >400 cells/µL (immunoconcordant, n = 33). We included 11 healthy individuals as reference. RESULTS: As expected, suboptimal CD4 T-cell recovery was associated with low frequencies of naïve cells, high frequencies of transitional and effector memory cells and a subsequent low ratio of central/transitional memory cells in the CD4 compartment. These alterations correlated with spontaneous CD4 T-cell death. A deeper analysis of cell death in CD4 T-cell subsets showed increased cell death in memory cells of immunodiscordant individuals, mainly affecting central memory cells. Immunosenescence was also higher in immunodiscordant individuals albeit unrelated to cell death. The CD8 compartment was similar in both HIV-infected groups, except for an underrepresentation of naïve cells in immunodiscordant individuals. CONCLUSION: Immunodiscordant individuals show alterations in memory CD4 T-cell differentiation associated with a short ex vivo lifespan of central memory cells and an in vivo low central/transitional memory cell ratio. These alterations may contribute to poor CD4 T-cell repopulation.


Assuntos
Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Memória Imunológica , Adulto , Contagem de Linfócito CD4 , Antígenos CD57/metabolismo , Linfócitos T CD8-Positivos/imunologia , Compartimento Celular , Morte Celular , Diferenciação Celular/imunologia , Feminino , Infecções por HIV/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia
4.
J Transl Med ; 11: 68, 2013 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-23514202

RESUMO

BACKGROUND: Chronic Fatigue Syndrome (CFS) is a debilitating neuro-immune disorder of unknown etiology diagnosed by an array of clinical manifestations. Although several immunological abnormalities have been described in CFS, their heterogeneity has limited diagnostic applicability. METHODS: Immunological features of CFS were screened in 22 CFS diagnosed individuals fulfilling Fukuda criteria and 30 control healthy individuals. Peripheral blood T, B and NK cell function and phenotype were analyzed by flow cytometry in both groups. RESULTS: CFS diagnosed individuals showed similar absolute numbers of T, B and NK cells, with minor differences in the percentage of CD4+ and CD8+ T cells. B cells showed similar subset frequencies and proliferative responses between groups. Conversely, significant differences were observed in T cell subsets. CFS individuals showed increased levels of T regulatory cells (CD25+/FOXP3+) CD4 T cells, and lower proliferative responses in vitro and in vivo. Moreover, CD8 T cells from the CFS group showed significantly lower activation and frequency of effector memory cells. No clear signs of T-cell immunosenescence were observed. NK cells from CFS individuals displayed higher expression of NKp46 and CD69 but lower expression of CD25 in all NK subsets defined. Overall, T cell and NK cell features clearly clustered CFS individuals. CONCLUSIONS: Our findings suggest that alterations in T-cell phenotype and proliferative response along with the specific signature of NK cell phenotype may be useful to identify CFS individuals. The striking down modulation of T cell mediated immunity may help to understand intercurrent viral infections in CFS.


Assuntos
Linfócitos B/imunologia , Síndrome de Fadiga Crônica/diagnóstico , Síndrome de Fadiga Crônica/imunologia , Células Matadoras Naturais/imunologia , Linfócitos T/imunologia , Adulto , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Relação CD4-CD8 , Morte Celular , Proliferação de Células , Análise por Conglomerados , Estudos de Coortes , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Lectinas Tipo C/metabolismo , Masculino , Pessoa de Meia-Idade , Fenótipo , Resultado do Tratamento
5.
Cytometry A ; 83(7): 648-58, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23650261

RESUMO

Increased lymphocyte death is a hallmark of human immunodeficiency virus (HIV) infection. Although virological factors have been linked to this phenomenon, increased cell death rates are still observed in treated individuals in which viral replication is halted. To understand the nature of this remaining altered cell death, we have developed a simple and fast assay to assess major cell death pathways in lymphocytes isolated from HIV-infected individuals. The combination of three factors: (i) antibody staining to identify CD3(+) CD4(+) and CD3(+) CD8(+) cells, (ii) assessment of mitochondrial and plasma membrane function using DiOC6(3) or JC-1 probes and vital dyes, and (iii) caspase inhibition, allowed for the quantification of caspase-independent and -dependent cell death in CD4 and CD8 T cells. The latter mechanism was divided in intrinsic and extrinsic apoptotic pathways according to the sensitivity of the dissipation of mitochondrial membrane potential to Z-VAD-fmk or Q-VD-oPH treatment. Our data show similar results for both caspase inhibitors in treated infected individuals, whereas Q-VD-oPH showed a more potent inhibition in viremic individuals, yielding lower levels of intrinsic apoptosis. Comparison of DiOC6(3) and JC-1 probes yielded similar results in CD4 T cells, allowing for a clear definition of death mechanism in these cells. However, in CD8 T-cells, JC-1 showed heterogeneous staining and detected significantly lower levels of cell death with a higher contribution of intrinsic apoptosis. In conclusion, we provide a simple method to assess CD4 T-cell death mechanisms in HIV-infected individuals. The reasons and consequences of mitochondrial heterogeneity in CD8 T-cells require further evaluation.


Assuntos
Apoptose/imunologia , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Infecções por HIV/imunologia , Clorometilcetonas de Aminoácidos/farmacologia , Apoptose/efeitos dos fármacos , Benzimidazóis/química , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/virologia , Carbocianinas/química , Estudos de Casos e Controles , Inibidores de Caspase/farmacologia , Citometria de Fluxo , Corantes Fluorescentes , Humanos , Necrose , Propídio/química , Quinolinas/farmacologia , Coloração e Rotulagem
6.
Retrovirology ; 9: 15, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22333046

RESUMO

BACKGROUND: Resistance to the fusion inhibitor enfuvirtide (ENF) is achieved by changes in the gp41 subunit of the HIV envelope glycoprotein (Env). Specific ENF-associated mutational pathways correlate with immunological recovery, even after virological failure, suggesting that the acquisition of ENF resistance alters gp41 pathogenicity. To test this hypothesis, we have characterized the expression, fusion capability, induction of CD4+ T cell loss and single CD4+ T cell death of 48 gp41 proteins derived from three patients displaying different amino acids (N, T or I) at position 140 that developed a V38A mutation after ENF-based treatment. RESULTS: In all cases, intra-patient comparison of Env isolated pre- or post-treatment showed comparable values of expression and fusogenic capacity. Furthermore, Env with either N or T at position 140 induced comparable losses of CD4+ T-cells, irrespective of the residue present at position 38. Conversely, Env acquiring the V38A mutation in a 140I background induced a significantly reduced loss of CD4+ T cells and lower single-cell death than did their baseline controls. No altered ability to induce single-cell death was observed in the other clones. CONCLUSIONS: Overall, primary gp41 proteins with both V38A and N140I changes showed a reduced ability to induce single cell death and deplete CD4+ T cells, despite maintaining fusion activity. The specificity of this phenotype highlights the relevance of the genetic context to the cytopathic capacity of Env and the role of ENF-resistance mutations in modulating viral pathogenicity in vivo, further supporting the hypothesis that gp41 is a critical mediator of HIV pathogenesis.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Farmacorresistência Viral , Proteína gp41 do Envelope de HIV/administração & dosagem , Proteína gp41 do Envelope de HIV/genética , HIV-1/patogenicidade , Mutação de Sentido Incorreto , Fragmentos de Peptídeos/administração & dosagem , Fatores de Virulência/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Fármacos Anti-HIV/farmacologia , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD4-Positivos/virologia , Sobrevivência Celular , Enfuvirtida , Proteína gp41 do Envelope de HIV/metabolismo , Proteína gp41 do Envelope de HIV/farmacologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Dados de Sequência Molecular , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fragmentos de Peptídeos/farmacologia , Virulência , Fatores de Virulência/metabolismo
7.
Dis Model Mech ; 15(3)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35344038

RESUMO

Cancer continues to be a leading cause of death worldwide, largely due to metastases and cachexia. It is a complex disease that is commonly associated with a variety of comorbidities. With global increases in ageing populations and obesity, multimorbidity is a rapidly growing clinical issue in the context of cancer. Cancer is also genetically heterogeneous, with a tumour's unique profile determining its incidence of metastasis, degree of cachexia and response to therapeutics. These complexities of human cancer are difficult to replicate in animal models and are, in part, responsible for the failures in translational cancer research. In this Perspective, we highlight the fruit fly, Drosophila melanogaster, as a powerful model organism to investigate multimorbidity and tumour diversity. We also highlight how harnessing these complexities in Drosophila can, potentially, enhance cancer research and advance therapeutic discoveries.


Assuntos
Drosophila , Neoplasias , Animais , Caquexia , Modelos Animais de Doenças , Drosophila melanogaster/fisiologia , Neoplasias/complicações
8.
Front Immunol ; 13: 993401, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304456

RESUMO

Intravesical BCG instillation after bladder tumor resection is the standard treatment for non-muscle invasive bladder cancer; however, it is not always effective and frequently has undesirable side effects. Therefore, new strategies that improve the clinical management of patients are urgently needed. This study aimed to comprehensively evaluate the bladder tumor immune microenvironment profile after intravesical treatment with a panel of mycobacteria with variation in their cell envelope composition and its impact on survival using an orthotopic murine model to identify more effective and safer therapeutic strategies. tumor-bearing mice were intravesically treated with a panel of BCG and M. brumae cultured under different conditions. Untreated tumor-bearing mice and healthy mice were also included as controls. After mycobacterial treatments, the infiltrating immune cell populations in the bladder were analysed by flow cytometry. We provide evidence that mycobacterial treatment triggered a strong immune infiltration into the bladder, with BCG inducing higher global absolute infiltration than M. brumae. The induced global immune microenvironment was strikingly different between the two mycobacterial species, affecting both innate and adaptive immunity. Compared with M. brumae, BCG treated mice exhibited a more robust infiltration of CD4+ and CD8+ T-cells skewed toward an effector memory phenotype, with higher frequencies of NKT cells, neutrophils/gMDSCs and monocytes, especially the inflammatory subset, and higher CD4+ TEM/CD4+ Treg and CD8+ TEM/CD4+ Treg ratios. Conversely, M. brumae treatment triggered higher proportions of total activated immune cells and activated CD4+ and CD8+ TEM cells and lower ratios of CD4+ TEM cells/CD4+ Tregs, CD8+ TEM cells/CD4+ Tregs and inflammatory/reparative monocytes. Notably, the mycobacterial cell envelope composition in M. brumae had a strong impact on the immune microenvironment, shaping the B and myeloid cell compartment and T-cell maturation profile and thus improving survival. Overall, we demonstrate that the bladder immune microenvironment induced by mycobacterial treatment is species specific and shaped by mycobacterial cell envelope composition. Therefore, the global bladder immune microenvironment can be remodelled, improving the quality of infiltrating immune cells, the balance between inflammatory and regulatory/suppressive responses and increasing survival.


Assuntos
Mycobacterium , Neoplasias da Bexiga Urinária , Camundongos , Animais , Bexiga Urinária , Neoplasias da Bexiga Urinária/tratamento farmacológico , Linfócitos T CD8-Positivos , Vacina BCG/uso terapêutico , Microambiente Tumoral
9.
Sci Rep ; 12(1): 7439, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523829

RESUMO

A complex link exists between HIV-1 and autophagy, and discordant results have been reported in different in vitro models regarding the way HIV and autophagy modulate each other. Despite this, there is very limited knowledge about the interplay between HIV and autophagy in vivo in lymphoid tissue, due in part by the lack of cell models that recapitulate the in vivo setting. Here, we evaluate the interrelationship between HIV and autophagy using human ex vivo lymphoid tissue cultures as an HIV infection model. Our results showed that human lymphoid aggregated cultures (HLACs) from tonsillar tissue displayed fully functional autophagic activity. In this system, HIV infection resulted in an increase in autophagy. Notably, we observed that both, autophagy-enhancing (rapamycin) or blocking drugs (3-methyladenine, chloroquine and bafilomycin), were able to decrease HIV-DNA levels and HIV replication. Therefore, efficient HIV-1 replication requires a fine-tuned level of autophagy, so modifications of this balance will have a negative impact on its replication. Therefore, targeting the autophagic pathway could be a new therapeutic approach to be explored to treat HIV-1 infection. Ex vivo cultures of human lymphoid tissue are a suitable model to obtain further insights into HIV and its intricate relationship with autophagy.


Assuntos
Infecções por HIV , HIV-1 , Autofagia , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Tecido Linfoide , Replicação Viral
10.
Oncoimmunology ; 11(1): 2051845, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355681

RESUMO

The mechanism of action of intravesical Mycobacterium bovis BCG immunotherapy treatment for bladder cancer is not completely known, leading to misinterpretation of BCG-unresponsive patients, who have scarce further therapeutic options. BCG is grown under diverse culture conditions worldwide, which can impact the antitumor effect of BCG strains and could be a key parameter of treatment success. Here, BCG and the nonpathogenic Mycobacterium brumae were grown in four culture media currently used by research laboratories and BCG manufacturers: Sauton-A60, -G15 and -G60 and Middlebrook 7H10, and used as therapies in the orthotopic murine BC model. Our data reveal that each mycobacterium requires specific culture conditions to induce an effective antitumor response. since higher survival rates of tumor-bearing mice were achieved using M. brumae-A60 and BCG-G15 than the rest of the treatments. M. brumae-A60 was the most efficacious among all tested treatments in terms of mouse survival, cytotoxic activity of splenocytes against tumor cells, higher systemic production of IL-17 and IFN-É£, and bladder infiltration of selected immune cells such as ILCs and CD4TEM. BCG-G15 triggered an antitumor activity based on a massive infiltration of immune cells, mainly CD3+ (CD4+ and CD8+) T cells, together with high systemic IFN-É£ release. Finally, a reduced variety of lipids was strikingly observed in the outermost layer of M. brumae-A60 and BCG-G15 compared to the rest of the cultures, suggesting an influence on the antitumor immune response triggered. These findings contribute to understand how mycobacteria create an adequate niche to help the host subvert immunosuppressive tumor actions.


Assuntos
Mycobacterium bovis , Neoplasias da Bexiga Urinária , Animais , Humanos , Imunoterapia , Interleucina-17 , Camundongos , Bexiga Urinária , Neoplasias da Bexiga Urinária/tratamento farmacológico
11.
Front Immunol ; 13: 1055042, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36561760

RESUMO

Preventing new HIV infections remains a global challenge. Young women continue to bear a disproportionate burden of infection. Oral pre-exposure prophylaxis (PrEP), offers a novel women-initiated prevention technology and PrEP trials completed to date underscore the importance of their inclusion early in trials evaluating new HIV PrEP technologies. Data from completed topical and systemic PrEP trials highlight the role of gender specific physiological and social factors that impact PrEP uptake, adherence and efficacy. Here we review the past and current developments of HIV-1 prevention options for women with special focus on PrEP considering the diverse factors that can impact PrEP efficacy. Furthermore, we highlight the importance of inclusion of female scientists, clinicians, and community advocates in scientific efforts to further improve HIV prevention strategies.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Profilaxia Pré-Exposição , Humanos , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Soropositividade para HIV/tratamento farmacológico
12.
Immunology ; 133(3): 318-28, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21501161

RESUMO

Infection with HIV-1 frequently results in the loss of specific cellular immune responses and an associated lack of antibodies. Recombinant growth hormone (rGH) administration reconstitutes thymic tissue and boosts the levels of peripheral T cells, so rGH therapy may be an effective adjuvant through promoting the recovery of lost cellular and T-cell-dependent humoral immune responses in immunosuppressed individuals. To test this concept, we administered rGH to a clinically defined group of HIV-1-infected subjects with defective cellular and serological immune responses to at least one of three commonly employed vaccines (hepatitis A, hepatitis B or tetanus toxoid). Of the original 278 HIV-1-infected patients entering the trial, only 20 conformed to these immunological criteria and were randomized into three groups: Group A (n = 8) receiving rGH and challenged with the same vaccine to which they were unresponsive and Groups B (n = 5) and C (n = 7) who received either rGH or vaccination alone, respectively. Of the eight subjects in Group A, five recovered CD4 cellular responses to vaccine antigen and four of these produced the corresponding antibodies. In the controls, three of the five in group B recovered cellular responses with two producing antibodies, whereas three of the seven in Group C recovered CD4 responses, with only two producing antibodies. Significantly, whereas seven of ten patients receiving rGH treatment in Group A (six patients) and B (one patient) recovered T-cell responses to HIVp24, only two of six in Group C responded similarly. In conclusion, reconstitution of the thymus in immunosuppressed adults through rGH hormone treatment restored both specific antibody and CD4 T-cell responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1 , Imunidade Celular , Imunidade Humoral , Hospedeiro Imunocomprometido , Timo/imunologia , Adulto , Relação CD4-CD8 , Linfócitos T CD4-Positivos/citologia , Quimioterapia Adjuvante , Hormônio do Crescimento/farmacologia , Infecções por HIV/tratamento farmacológico , Humanos , Tamanho do Órgão/efeitos dos fármacos , Timo/citologia , Timo/efeitos dos fármacos , Vacinas Virais/administração & dosagem
13.
Front Microbiol ; 12: 661446, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995324

RESUMO

HIV/AIDS is still a global threat despite the notable efforts made by the scientific and health communities to understand viral infection, to design new drugs or to improve existing ones, as well as to develop advanced therapies and vaccine designs for functional cure and viral eradication. The identification and analysis of HIV-1 positive individuals that naturally control viral replication in the absence of antiretroviral treatment has provided clues about cellular processes that could interact with viral proteins and RNA and define subsequent viral replication and clinical progression. This is the case of autophagy, a degradative process that not only maintains cell homeostasis by recycling misfolded/old cellular elements to obtain nutrients, but is also relevant in the innate and adaptive immunity against viruses, such as HIV-1. Several studies suggest that early steps of HIV-1 infection, such as virus binding to CD4 or membrane fusion, allow the virus to modulate autophagy pathways preparing cells to be permissive for viral infection. Confirming this interplay, strategies based on autophagy modulation are able to inhibit early steps of HIV-1 infection. Moreover, autophagy dysregulation in late steps of the HIV-1 replication cycle may promote autophagic cell-death of CD4+ T cells or control of HIV-1 latency, likely contributing to disease progression and HIV persistence in infected individuals. In this scenario, understanding the molecular mechanisms underlying HIV/autophagy interplay may contribute to the development of new strategies to control HIV-1 replication. Therefore, the aim of this review is to summarize the knowledge of the interplay between autophagy and the early events of HIV-1 infection, and how autophagy modulation could impair or benefit HIV-1 infection and persistence, impacting viral pathogenesis, immune control of viral replication, and clinical progression of HIV-1 infected patients.

14.
Antioxidants (Basel) ; 10(12)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34943007

RESUMO

The aim of this study was to develop a new hybrid biomaterial that could photo-stabilize and improve the photoprotective capacity of a Baccharis antioquensis extract. Different combinations of lignin/gelatin/natural extract were applied to prepare hybrid biomaterial nanoparticles (NPs), which were then incorporated into an emulsion. The in vitro photoprotection and photostability were evaluated. The methanolic extract showed high phenolic content (646.4 ± 9.5 mg GAE/g dry extract) and a DPPH radical assay revealed that the antiradical capacity of the extract (0.13 to 0.05 g extract/mmol DPPH) was even better than that of BHT. The particle size of the hybrid biomaterial ranged from 100 to 255 nm; a polydispersity index (PdI) between 0.416 and 0.788 is suitable for topical use in dermocosmetic products. The loading capacity of the extract ranged from 27.0 to 44.5%, and the nanoparticles (NPs) showed electrostatic stability in accordance with the zeta potential value. We found that the formulation based on lignin: extract (1:1 ratio) and gelatin: lignin: extract (0.5:0.5:1 ratio) demonstrated photoprotection qualities with a sun protection factor (SPF) ranging from 9.4 to 22.6. In addition, all the hybrid NP-formulations were time-stable with %SPFeff and %UVAPFeff greater than 80% after exposure to 2 h of radiation. These results suggest that the hybrid biopolymer-natural extract improved the photoprotection and photostability properties, as well as the antiradical capacity, of the B. antioquensis extract, and may be useful for trapping high polyphenol content from natural extracts, with potential application in cosmeceutical formulations.

15.
Viruses ; 13(9)2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34578296

RESUMO

Angiotensin converting enzyme 2 (ACE2) is a host ectopeptidase and the receptor for the SARS-CoV-2 virus, albeit virus-ACE2 interaction goes far beyond viral entry into target cells. Controversial data exists linking viral infection to changes in ACE2 expression and function, which might influence the subsequent induction of an inflammatory response. Here, we tested the significance of soluble ACE2 enzymatic activity longitudinally in nasopharyngeal swabs and plasma samples of SARS-CoV-2 infected patients, along with the induction of inflammatory cytokines. Release of soluble functional ACE2 increases upon SARS-CoV-2 infection in swabs and plasma of infected patients, albeit rapidly decreasing during infection course in parallel with ACE2 gene expression. Similarly, SARS-CoV-2 infection also induced the expression of inflammatory cytokines. These changes positively correlated with the viral load. Overall, our results demonstrate the existence of mechanisms by which SARS-CoV-2 modulates ACE2 expression and function, intracellular viral sensing and subsequent inflammatory response, offering new insights into ACE2 dynamics in the human upper respiratory tract and pointing towards soluble ACE2 levels as a putative early biomarker of infection severity.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Interações Hospedeiro-Patógeno , SARS-CoV-2/fisiologia , Enzima de Conversão de Angiotensina 2/genética , Biomarcadores , COVID-19/diagnóstico , COVID-19/imunologia , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Expressão Gênica , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , SARS-CoV-2/isolamento & purificação , Carga Viral
16.
Front Immunol ; 11: 582330, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329554

RESUMO

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex neuroimmune disorder characterized by numerous symptoms of unknown etiology. The ME/CFS immune markers reported so far have failed to generate a clinical consensus, perhaps partly due to the limitations of biospecimen biobanking. To address this issue, we performed a comparative analysis of the impact of long-term biobanking on previously identified immune markers and also explored additional potential immune markers linked to infection in ME/CFS. A correlation analysis of marker cryostability across immune cell subsets based on flow cytometry immunophenotyping of fresh blood and frozen PBMC samples collected from individuals with ME/CFS (n = 18) and matched healthy controls (n = 18) was performed. The functionality of biobanked samples was assessed on the basis of cytokine production assay after stimulation of frozen PBMCs. T cell markers defining Treg subsets and the expression of surface glycoprotein CD56 in T cells and the frequency of the effector CD8 T cells, together with CD57 expression in NK cells, appeared unaltered by biobanking. By contrast, NK cell markers CD25 and CD69 were notably increased, and NKp46 expression markedly reduced, by long-term cryopreservation and thawing. Further exploration of Treg and NK cell subsets failed to identify significant differences between ME/CFS patients and healthy controls in terms of biobanked PBMCs. Our findings show that some of the previously identified immune markers in T and NK cell subsets become unstable after cell biobanking, thus limiting their use in further immunophenotyping studies for ME/CFS. These data are potentially relevant for future multisite intervention studies and cooperative projects for biomarker discovery using ME/CFS biobanked samples. Further studies are needed to develop novel tools for the assessment of biomarker stability in cryopreserved immune cells from people with ME/CFS.


Assuntos
Biomarcadores/metabolismo , Células Sanguíneas/metabolismo , Síndrome de Fadiga Crônica/diagnóstico , Células Matadoras Naturais/metabolismo , Subpopulações de Linfócitos/metabolismo , Linfócitos T/metabolismo , Adulto , Estudos de Casos e Controles , Células Cultivadas , Estudos de Coortes , Criopreservação , Feminino , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Food Sci Technol Int ; 26(2): 160-172, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31547687

RESUMO

Gluten-free breads were developed by incorporating unripe banana flour in a blend of alternative flour/cassava starch, 45/50. A factorial design was applied to determine the simultaneous effect of percentage of unripe banana flour (2, 8, 15%) and the type of alternative flour (quinoa, oyster mushroom, yellow pea and lentil flour) on structural and colour properties of bread. Principal component analysis was used to evaluate the behaviour of the formulations from a comprehensive perspective. Three formulations, denoted as P8 (pea + 8% unripe banana flour), Q15 (quinoa + 15% unripe banana flour) and L15 (lentil + 15% unripe banana flour) exhibited the closest profiles to reference (wheat bread). Breads with oyster mushroom flour showed a profile significantly different from the rest of formulations. The interactions among the factors were significant for all studied properties and showed that the unripe banana flour fortification did not lead to proportional responses on the bread properties, but the behaviour of unripe banana flour in breadmaking relied on the percentage and the type of alternative flour used. The P8, Q15 and L15 exhibited high fibre content and carbohydrate content lower than the reference. In addition, P8 formulation can be classified as intermediate glycaemic index.


Assuntos
Pão/análise , Farinha/análise , Musa/química , Chenopodium quinoa/química , Cor , Fibras na Dieta/análise , Análise de Alimentos , Manipulação de Alimentos , Glutens/análise , Índice Glicêmico , Análise de Componente Principal , Amido/química , Triticum/química
18.
Retrovirology ; 6: 89, 2009 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-19825175

RESUMO

Although cell-to-cell HIV transmission was defined in early 90's, in the last five years, several groups have underscored the relevance of this mode of HIV spread between productively infected and uninfected CD4 T cells by defining the term virological synapse (VS). However, unraveling the molecular mechanisms of this efficient mode of viral spread appears to be more controversial than expected. Different authors have highlighted the role of a classical co-receptor-dependent HIV transmission while others describe a co-receptor-independent mechanism as predominant in VS. By analyzing different cellular models (primary cells and cell lines), we suggest that primary cells are highly sensitive to the physical passage of viral particles across the synapses, a co-receptor-independent phenomenon that we call "HIV transfer". Once viral particles are transferred, they can infect target cells by a co-receptor-dependent mechanism that fits with the classical meaning of "HIV transmission" and that is much more efficient in cell lines. Differences in the ability of primary CD4 T cells and cell lines to support HIV transfer and transmission explain most of the reported controversial data and should be taken into account when analyzing cell-to-cell HIV spread. Moreover, the terms transfer and transmission may be useful to define the events occurring at the VS. Thus, HIV particles would be transferred across synapses, while HIV infection would be transmitted between cells. Chronologically, HIV transfer is an early event occurring immediately after the VS formation, which precedes but does not inevitably lead to transmission, a late event resulting in infection.


Assuntos
Linfócitos T CD4-Positivos/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Modelos Biológicos
19.
Molecules ; 14(5): 1927-37, 2009 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-19471212

RESUMO

Considering as a lead molecule the chemokine CXCR4 receptor antagonist AMD-3100, which shows significant anti-HIV activity in vitro and in vivo, we investigated a series of structurally related macrocyclic polyamines incorporating o,o'-phenanthroline or 2,2'-bipyridyl scaffolds as potential antiviral agents with lower toxicity and increased activity against both wild type X4-tropic and dual tropic HIV strains. The antiviral activity of these compounds was evaluated by susceptibility assays in PBMC (Peripheral Blood Mononuclear Cells) and compared to that of AMD-3100. The newly investigated compounds showed IC(50)s values in the low micromolar range and significantly inhibited the viral replication of wild type X4-tropic isolate and dual tropic strains. These macrocyclic polyamines constitute a promising class of HIV entry inhibitors.


Assuntos
Aminas/química , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Resistência a Múltiplos Medicamentos , Farmacorresistência Viral , Inibidores da Fusão de HIV/química , Inibidores da Fusão de HIV/farmacologia , HIV-1/efeitos dos fármacos , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/uso terapêutico , Benzilaminas , Ciclamos , Inibidores da Fusão de HIV/síntese química , Inibidores da Fusão de HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/uso terapêutico , Humanos , Estrutura Molecular , Fenótipo , Poliaminas/síntese química , Poliaminas/química , Poliaminas/farmacologia , Poliaminas/uso terapêutico , Receptores CXCR4/antagonistas & inibidores
20.
Oncoimmunology ; 8(8): 1602460, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413912

RESUMO

Intravesical Bacille Calmette-Guérin (BCG) remains the most effective treatment for high-risk non-muscle-invasive bladder cancer (NMIBC), unfortunately there is no validated biomarker to predict clinical outcome. Here we tried to explore the possibility that a combination of the density of peritumoral infiltrating cells (Th1, Th2 and PD-L1) and the composition of peripheral immune cells (neutrophil and lymphocyte counts) could generate a more reliable prognostic biomarker. Twenty-two patients with high-risk NMIBC treated with BCG (10 BCG nonresponders and 12 BCG responders) were selected. BCG responders had significantly lower level of peritumoral T-bet+ cells with an associated higher GATA-3+/T-bet+ ratio (p = 0.04, p = 0.02, respectively). Furthermore, the immune polarization in tissue (GATA-3+/T-bet+ ratio) adjusted for the systemic inflammation (neutrophil-to-lymphocyte ratio) showed a significantly higher association with the BCG response (p = 0.004). A survival analysis demonstrated prolonged recurrence-free survival (RFS) in patients with a lower T-bet+/Lymphocyte ratio and higher GTR/NLR (p = 0.01). No association was observed between peritumoral PD-L1+ expression and the BCG response. In conclusion, alterations in overall immune function, both local and systemic, may influence the therapeutic response to BCG, therefore a combined analysis of tumoral (Th2/Th1 ratio) and peripheral (NLR) immune composition prior to treatment may be a promising approach to predict the BCG response in high-risk NMIBC patients.

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