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1.
Vaccines (Basel) ; 12(8)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39203962

RESUMO

Therapeutic cancer vaccines have been considered in recent decades as important immunotherapeutic strategies capable of leading to tumor regression. In the development of these vaccines, the identification of neoepitopes plays a critical role, and different computational methods have been proposed and employed to direct and accelerate this process. In this context, this review identified and systematically analyzed the most recent studies published in the literature on the computational prediction of epitopes for the development of therapeutic vaccines, outlining critical steps, along with the associated program's strengths and limitations. A scoping review was conducted following the PRISMA extension (PRISMA-ScR). Searches were performed in databases (Scopus, PubMed, Web of Science, Science Direct) using the keywords: neoepitope, epitope, vaccine, prediction, algorithm, cancer, and tumor. Forty-nine articles published from 2012 to 2024 were synthesized and analyzed. Most of the identified studies focus on the prediction of epitopes with an affinity for MHC I molecules in solid tumors, such as lung carcinoma. Predicting epitopes with class II MHC affinity has been relatively underexplored. Besides neoepitope prediction from high-throughput sequencing data, additional steps were identified, such as the prioritization of neoepitopes and validation. Mutect2 is the most used tool for variant calling, while NetMHCpan is favored for neoepitope prediction. Artificial/convolutional neural networks are the preferred methods for neoepitope prediction. For prioritizing immunogenic epitopes, the random forest algorithm is the most used for classification. The performance values related to the computational models for the prediction and prioritization of neoepitopes are high; however, a large part of the studies still use microbiome databases for training. The in vitro/in vivo validations of the predicted neoepitopes were verified in 55% of the analyzed studies. Clinical trials that led to successful tumor remission were identified, highlighting that this immunotherapeutic approach can benefit these patients. Integrating high-throughput sequencing, sophisticated bioinformatics tools, and rigorous validation methods through in vitro/in vivo assays as well as clinical trials, the tumor neoepitope-based vaccine approach holds promise for developing personalized therapeutic vaccines that target specific tumor cancers.

2.
Microorganisms ; 12(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38792746

RESUMO

Diagnosing canine visceral leishmaniasis (CVL) in Brazil faces challenges due to the limitations regarding the sensitivity and specificity of the current diagnostic protocol. Therefore, it is urgent to map new antigens or enhance the existing ones for future diagnostic techniques. Immunoinformatic tools are promising in the identification of new potential epitopes or antigen candidates. In this study, we evaluated peptides selected by epitope prediction for CVL serodiagnosis in ELISA assays. Ten B-cell epitopes were immunogenic in silico, but two peptides (peptides No. 45 and No. 48) showed the best performance in vitro. The selected peptides, both individually and in combination, were highly diagnostically accurate, with sensitivities ranging from 86.4% to 100% and with a specificity of approximately 90%. We observed that the combination of peptides showed better performance when compared to peptide alone, by detecting all asymptomatic dogs, showing lower cross-reactivity in sera from dogs with other canine infections, and did not detect vaccinated animals. Moreover, our data indicate the potential use of immunoinformatic tools associated with ELISA assays for the selection and evaluation of potential new targets, such as peptides, applied to the diagnosis of CVL.

3.
Actas Esp Psiquiatr ; 52(2): 172-182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622003

RESUMO

Insomnia disorder is a common condition that is considered a risk factor for multiple physical and mental disorders, contributing to reduced quality of life and increased healthcare expenditures. Although cognitive behavioral therapy (CBT) is typically recommended as the primary intervention, its accessibility is hindered by limited resources, prompting the prevalent use of pharmacological interventions as the primary treatment in clinical settings. This study reviews the benefits and risks of current pharmacological treatments for insomnia, with special reference to the orexinergic system as a novel therapeutic target for treatment. The prescription of GABAergic mechanism enhancers (benzodiazepine (BZD) and "Z drugs") has shown efficacy in short-term insomnia treatment (less than 4 weeks), however, concerns arise regarding their long-term effectiveness, unfavorable tolerability and safety profiles, including the potential for dependency. Drugs with antihistamine properties, including certain antidepressants and antipsychotics, exhibit short-term efficacy but have documented tolerability limitations, especially in the elderly. The use of melatonin, available in various formulations, lacks comprehensive long-term data. Dual orexin receptor antagonists (DORAs) such as daridorexant, lemborexant, and suvorexant, represent a novel approach to insomnia treatment by inhibiting wakefulness rather than enhancing sedation. As the only DORA approved for insomnia treatment by the European Medicines Agency (EMA) and Food and Drug Administration (FDA), daridorexant has demonstrated sustained efficacy over a 12-month period, improving nocturnal sleep parameters and daytime functionality, with a favorable safety and tolerability profile.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Idoso , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Qualidade de Vida , Sono , Benzodiazepinas , Antidepressivos
4.
Actas esp. psiquiatr ; 52(2): 172-178, 2024. graf
Artigo em Inglês | IBECS | ID: ibc-232350

RESUMO

Insomnia disorder is a common condition that is considered a risk factor for multiple physical and mental disorders, contributing to reduced quality of life and increased healthcare expenditures. Although cognitive behavioral therapy (CBT) is typically recommended as the primary intervention, its accessibility is hindered by limited resources, prompting the prevalent use of pharmacological interventions as the primary treatment in clinical settings. This study reviews the benefits and risks of current pharmacological treatments for insomnia, with special reference to the orexinergic system as a novel therapeutic target for treatment. The prescription of GABAergic mechanism enhancers (benzodiazepine (BZD) and “Z drugs”) has shown efficacy in short-term insomnia treatment (less than 4 weeks), however, concerns arise regarding their long-term effectiveness, unfavorable tolerability and safety profiles, including the potential for dependency. Drugs with antihistamine properties, including certain antidepressants and antipsychotics, exhibit short-term efficacy but have documented tolerability limitations, especially in the elderly. The use of melatonin, available in various formulations, lacks comprehensive long-term data. Dual orexin receptor antagonists (DORAs) such as daridorexant, lemborexant, and suvorexant, represent a novel approach to insomnia treatment by inhibiting wakefulness rather than enhancing sedation. As the only DORA approved for insomnia treatment by the European Medicines Agency (EMA) and Food and Drug Administration (FDA), daridorexant has demonstrated sustained efficacy over a 12-month period, improving nocturnal sleep parameters and daytime functionality, with a favorable safety and tolerability profile. (AU)


Assuntos
Humanos , Distúrbios do Início e da Manutenção do Sono , Benzodiazepinas , Orexinas , Antagonistas dos Receptores de Orexina
5.
Eur Neuropsychopharmacol ; 75: 80-92, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37603902

RESUMO

Little is known about genetic predisposition to relapse. Previous studies have linked cognitive and psychopathological (mainly schizophrenia and bipolar disorder) polygenic risk scores (PRS) with clinical manifestations of the disease. This study aims to explore the potential role of PRS from major mental disorders and cognition on schizophrenia relapse. 114 patients recruited in the 2EPs Project were included (56 patients who had not experienced relapse after 3 years of enrollment and 58 patients who relapsed during the 3-year follow-up). PRS for schizophrenia (PRS-SZ), bipolar disorder (PRS-BD), education attainment (PRS-EA) and cognitive performance (PRS-CP) were used to assess the genetic risk of schizophrenia relapse.Patients with higher PRS-EA, showed both a lower risk (OR=0.29, 95% CI [0.11-0.73]) and a later onset of relapse (30.96± 1.74 vs. 23.12± 1.14 months, p=0.007. Our study provides evidence that the genetic burden of neurocognitive function is a potentially predictors of relapse that could be incorporated into future risk prediction models. Moreover, appropriate treatments for cognitive symptoms appear to be important for improving the long-term clinical outcome of relapse.

6.
Parasit Vectors ; 16(1): 167, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37217925

RESUMO

BACKGROUND: Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is a serious public health concern in Latin America. Nifurtimox and benznidazole (BZ), the only two drugs currently approved for the treatment of CD, have very low efficacies in the chronic phase of the disease and several toxic side effects. Trypanosoma cruzi strains that are naturally resistant to both drugs have been reported. We performed a comparative transcriptomic analysis of wild-type and BZ-resistant T. cruzi populations using high-throughput RNA sequencing to elucidate the metabolic pathways related to clinical drug resistance and identify promising molecular targets for the development of new drugs for treating CD. METHODS: All complementary DNA (cDNA) libraries were constructed from the epimastigote forms of each line, sequenced and analysed using the Prinseq and Trimmomatic tools for the quality analysis, STAR as the aligner for mapping the reads against the reference genome (T. cruzi Dm28c-2018), the Bioconductor package EdgeR for statistical analysis of differential expression and the Python-based library GOATools for the functional enrichment analysis. RESULTS: The analytical pipeline with an adjusted P-value of < 0.05 and fold-change > 1.5 identified 1819 transcripts that were differentially expressed (DE) between wild-type and BZ-resistant T. cruzi populations. Of these, 1522 (83.7%) presented functional annotations and 297 (16.2%) were assigned as hypothetical proteins. In total, 1067 transcripts were upregulated and 752 were downregulated in the BZ-resistant T. cruzi population. Functional enrichment analysis of the DE transcripts identified 10 and 111 functional categories enriched for the up- and downregulated transcripts, respectively. Through functional analysis we identified several biological processes potentially associated with the BZ-resistant phenotype: cellular amino acid metabolic processes, translation, proteolysis, protein phosphorylation, RNA modification, DNA repair, generation of precursor metabolites and energy, oxidation-reduction processes, protein folding, purine nucleotide metabolic processes and lipid biosynthetic processes. CONCLUSIONS: The transcriptomic profile of T. cruzi revealed a robust set of genes from different metabolic pathways associated with the BZ-resistant phenotype, proving that T. cruzi resistance mechanisms are multifactorial and complex. Biological processes associated with parasite drug resistance include antioxidant defenses and RNA processing. The identified transcripts, such as ascorbate peroxidase (APX) and iron superoxide dismutase (Fe-SOD), provide important information on the resistant phenotype. These DE transcripts can be further evaluated as molecular targets for new drugs against CD.


Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Humanos , Tripanossomicidas/farmacologia , Transcriptoma , Perfilação da Expressão Gênica , Doença de Chagas/tratamento farmacológico , Nitroimidazóis/farmacologia
7.
Psychiatry Res ; 325: 115249, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37178502

RESUMO

Cannabis use is highly prevalent in first-episode psychosis (FEP) and plays a critical role in its onset and prognosis, but the genetic underpinnings promoting both conditions are poorly understood. Current treatment strategies for cannabis cessation in FEP are clearly inefficacious. Here, we aimed to characterize the association between cannabis-related polygenic risk scores (PRS) on cannabis use and clinical course after a FEP. A cohort of 249 FEP individuals were evaluated during 12 months. Symptom severity was measured with the Positive and Negative Severity Scale and cannabis use with the EuropASI scale. Individual PRS for lifetime cannabis initiation (PRSCI) and cannabis use disorder (PRSCUD) were constructed. Current cannabis use was associated with increased positive symptoms. Cannabis initiation at younger ages conditioned the 12-month symptom progression. FEP patients with higher cannabis PRSCUD reported increased baseline cannabis use. PRSCI was associated with the course of negative and general symptomatology over follow-up. Cannabis use and symptom progression after a FEP were modulated by cannabis PRS, suggesting that lifetime initiation and use disorders may have partially independent genetic factors. These exploratory results may be the first step to identify those FEP patients more vulnerable to cannabis use and worse outcomes to ultimately develop tailored treatments.


Assuntos
Cannabis , Transtornos Psicóticos , Humanos , Cannabis/efeitos adversos , Transtornos Psicóticos/genética , Transtornos Psicóticos/terapia , Fatores de Risco , Herança Multifatorial
8.
Eur Child Adolesc Psychiatry ; 32(7): 1285-1295, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35048161

RESUMO

Recent evidence confirms the risks of discontinuity of care when young people make a transition from child and adolescent mental health services (CAMHS) to adult mental health services (AMHS), although robust data are still sparse. We aimed to identify when and how patients get lost to care during transition by tracking care pathways and identifying factors which influence dropping out of care during transition. This is a retrospective observational study of 760 patients who reached the transition age boundary within 12 months before transition time and being treated at CAMHS for at least during preceding 18 months. Data were collected at two time points: last visit to CAHMS and first visit to AHMS. Socio-demographic, clinical and service utilization variables on CAMHS treatment were collected. In the 12 months leading up to the transition boundary, 46.8% of subjects (n = 356) withdrew from CAHMS without further contact with AHMS, 9.3% withdrew from CAHMS but were referred to AHMS by other services, 29% were transferred from CAHMS to AHMS, 10% remained at CAHMS and 5% patients were transferred to alternative services. Fifty-six percent of subjects experience cessation of care before the transition age. The risk of dropout increases with shorter contact time in CAMHS, is greater in subjects without pharmacological treatment, and decreases in subjects with psychosis, bipolar disorder, eating disorders, mental retardation, and neurodevelopmental disorders. This study confirms that a large number of people drop out of care as they approach the CAMHS transition and experience discontinuity of care during this critical period.


Assuntos
Serviços de Saúde do Adolescente , Transtornos da Alimentação e da Ingestão de Alimentos , Serviços de Saúde Mental , Transtornos Psicóticos , Adulto , Criança , Humanos , Adolescente , Lactente , Estudos Retrospectivos
9.
Cell Immunol ; 380: 104592, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36084402

RESUMO

The development of an immunogenic, effective, and safe vaccine is essential as an alternative for disease control. The present study aimed to evaluate the immunogenicity and efficacy potential of a polyepitope T-cell antigen candidate against visceral leishmaniasis in a murine model. BALB/c mice were immunized with three doses subcutaneously with Poly-T Leish alone or adjuvanted with Saponin plus Monophosphoryl lipid A, with 15-day intervals between doses, and challenged with 107 stationary-phase Leishmania infantum promastigotes via tail vein. Immunogenicity and parasitism in spleen and liver of immunized mice were evaluated 45 days post-challenge. Our results revealed that the immunization with Poly-T Leish and Poly-T Leish/SM increases the percentage of specific T (CD4+ and CD8+) lymphocytes proliferation in vitro after antigen-specific stimulation. Also, Poly-T Leish and Poly-T Leish/SM groups showed a high percentage of IFN-γ and TNF-α-producing T cells, meanwhile, the Poly-T Leish/SM group also showed an increased percentage of multifunctional T cells producing double and triple-positive (IFN-γ+TNF-α+IL-2+) cytokines. The immunization with Poly-T Leish or Poly-T Leish/SM stimulated a decreased IL-4 and IL-10 compared to the Saline and adjuvant group. Poly-T Leish/SM immunized mice exhibit a noteworthy reduction in the parasite burden (spleen and liver) through real-time PCR (96%). Moreover, we observed higher nitrite secretion in 120-hour stimulated-culture supernatant using Griess method. We demonstrated that the Poly-T Leish/SM candidate was potentially immunogenic, providing enhancement of protective immune mechanisms, and conferred protection reducing parasitism. Our candidate was considered potential against visceral leishmaniasis, and eventually, could be tested in phase I and II clinical trials in dogs.


Assuntos
Leishmania infantum , Vacinas contra Leishmaniose , Leishmaniose Visceral , Adjuvantes Imunológicos/farmacologia , Animais , Antígenos de Protozoários , Cães , Leishmaniose Visceral/prevenção & controle , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa
10.
CNS Spectr ; : 1-14, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35837681

RESUMO

This article is a clinical guide which discusses the "state-of-the-art" usage of the classic monoamine oxidase inhibitor (MAOI) antidepressants (phenelzine, tranylcypromine, and isocarboxazid) in modern psychiatric practice. The guide is for all clinicians, including those who may not be experienced MAOI prescribers. It discusses indications, drug-drug interactions, side-effect management, and the safety of various augmentation strategies. There is a clear and broad consensus (more than 70 international expert endorsers), based on 6 decades of experience, for the recommendations herein exposited. They are based on empirical evidence and expert opinion-this guide is presented as a new specialist-consensus standard. The guide provides practical clinical advice, and is the basis for the rational use of these drugs, particularly because it improves and updates knowledge, and corrects the various misconceptions that have hitherto been prominent in the literature, partly due to insufficient knowledge of pharmacology. The guide suggests that MAOIs should always be considered in cases of treatment-resistant depression (including those melancholic in nature), and prior to electroconvulsive therapy-while taking into account of patient preference. In selected cases, they may be considered earlier in the treatment algorithm than has previously been customary, and should not be regarded as drugs of last resort; they may prove decisively effective when many other treatments have failed. The guide clarifies key points on the concomitant use of incorrectly proscribed drugs such as methylphenidate and some tricyclic antidepressants. It also illustrates the straightforward "bridging" methods that may be used to transition simply and safely from other antidepressants to MAOIs.

11.
Front Cell Infect Microbiol ; 12: 826523, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774406

RESUMO

Leishmania amazonensis and Leishmania major are the causative agents of cutaneous and mucocutaneous diseases. The infections' outcome depends on host-parasite interactions and Th1/Th2 response, and in cutaneous form, regulation of Th17 cytokines has been reported to maintain inflammation in lesions. Despite that, the Th17 regulatory scenario remains unclear. With the aim to gain a better understanding of the transcription factors (TFs) and genes involved in Th17 induction, in this study, the role of inducing factors of the Th17 pathway in Leishmania-macrophage infection was addressed through computational modeling of gene regulatory networks (GRNs). The Th17 GRN modeling integrated experimentally validated data available in the literature and gene expression data from a time-series RNA-seq experiment (4, 24, 48, and 72 h post-infection). The generated model comprises a total of 10 TFs, 22 coding genes, and 16 cytokines related to the Th17 immune modulation. Addressing the Th17 induction in infected and uninfected macrophages, an increase of 2- to 3-fold in 4-24 h was observed in the former. However, there was a decrease in basal levels at 48-72 h for both groups. In order to evaluate the possible outcomes triggered by GRN component modulation in the Th17 pathway. The generated GRN models promoted an integrative and dynamic view of Leishmania-macrophage interaction over time that extends beyond the analysis of single-gene expression.


Assuntos
Leishmania major , Leishmania mexicana , Leishmaniose , Citocinas/metabolismo , Redes Reguladoras de Genes , Humanos , Leishmania mexicana/genética , Leishmania mexicana/metabolismo , Macrófagos
12.
Front Pharmacol ; 12: 729474, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483940

RESUMO

Antipsychotics (APs) are associated with weight gain and other metabolic abnormalities such as hyperglycemia, dyslipidemia and metabolic syndrome. This translational study aimed to uncover the underlying molecular mechanisms and identify the key genes involved in AP-induced metabolic effects. An integrative gene expression analysis was performed in four different mouse tissues (striatum, liver, pancreas and adipose) after risperidone or olanzapine treatment. The analytical approach combined the identification of the gene co-expression modules related to AP treatment, gene set enrichment analysis and protein-protein interaction network construction. We found several co-expression modules of genes involved in glucose and lipid homeostasis, hormone regulation and other processes related to metabolic impairment. Among these genes, EP300, which encodes an acetyltransferase involved in transcriptional regulation, was identified as the most important hub gene overlapping the networks of both APs. Then, we explored the genetically predicted EP300 expression levels in a cohort of 226 patients with first-episode psychosis who were being treated with APs to further assess the association of this gene with metabolic alterations. The EP300 expression levels were significantly associated with increases in body weight, body mass index, total cholesterol levels, low-density lipoprotein cholesterol levels and triglyceride concentrations after 6 months of AP treatment. Taken together, our analysis identified EP300 as a key gene in AP-induced metabolic abnormalities, indicating that the dysregulation of EP300 function could be important in the development of these side effects. However, more studies are needed to disentangle the role of this gene in the mechanism of action of APs.

13.
Future Microbiol ; 16: 589-606, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33998266

RESUMO

Aim: To predict glycosylphosphatidylinositol (GPI)-anchored proteins in the genome of Paracoccidioides brasiliensis and Paracoccidioides lutzii. Materials & methods: Five different bioinformatics tools were used for predicting GPI-anchored proteins; we considered as GPI-anchored proteins those detected by at least two in silico analysis methods. We also performed the proteomic analysis of P. brasiliensis cell wall by mass spectrometry. Results: Hundred GPI-anchored proteins were predicted in P. brasiliensis and P. lutzii genomes. A series of 57 proteins were classified in functional categories and 43 conserved proteins were reported with unknown functions. Four proteins identified by in silico analyses were also identified in the cell wall proteome. Conclusion: The data obtained in this study are important resources for future research of GPI-anchored proteins in Paracoccidioides spp. to identify targets for new diagnostic tools, drugs and immunological tests.


Assuntos
Proteínas Fúngicas/genética , Glicosilfosfatidilinositóis/metabolismo , Proteínas de Membrana/genética , Paracoccidioides/metabolismo , Sequência de Aminoácidos , Parede Celular/genética , Parede Celular/metabolismo , Biologia Computacional , Sequência Conservada , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Genoma Fúngico/genética , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Fases de Leitura Aberta , Paracoccidioides/genética , Paracoccidioides/patogenicidade , Paracoccidioidomicose/microbiologia , Proteômica , Virulência
14.
Parasit Vectors ; 14(1): 273, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022931

RESUMO

BACKGROUND: Panstrongylus megistus is the most important vector of Chagas disease in Brazil. Studies show that the principal factor hindering the control of triatomines is reinfestation of houses previously treated with insecticides. Studies at the microgeographic level are therefore necessary to better understand these events. However, an efficient molecular marker is not yet available for carrying out such analyses in this species. The aim of the present study was to identify and characterize microsatellite loci for future population genetic studies of P. megistus. METHODS: This study work consisted of five stages: (i) sequencing of genomic DNA; (ii) assembly and selection of contigs containing microsatellites; (iii) validation of amplification and evaluation of polymorphic loci; (iv) standardization of the polymorphic loci; and (v) verification of cross-amplification with other triatomine species. RESULTS: Sequencing of males and females generated 7,908,463 contigs with a total length of 2,043,422,613 bp. A total of 2,043,690 regions with microsatellites in 1,441,091 contigs were obtained, with mononucleotide repeats being the most abundant class. From a panel of 96 loci it was possible to visualize polymorphisms in 64.55% of the loci. Of the 20 loci genotyped, the number of alleles varied from two to nine with an average of 4.9. Cross-amplification with other species of triatomines was observed in 13 of the loci. CONCLUSIONS: Due to the high number of alleles encountered, polymorphism and the capacity to amplify from geographically distant populations, the microsatellites described here show promise for utilization in population genetic studies of P. megistus.


Assuntos
Genética Populacional/métodos , Insetos Vetores/genética , Repetições de Microssatélites , Panstrongylus/genética , Animais , Brasil , Doença de Chagas/transmissão , Feminino , Masculino , Projetos de Pesquisa , Análise de Sequência de DNA
15.
Front Cell Infect Microbiol ; 11: 653670, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996631

RESUMO

Neglected Tropical Diseases include a broad range of pathogens, hosts, and vectors, which represent evolving complex systems. Leishmaniasis, caused by different Leishmania species and transmitted to humans by sandflies, are among such diseases. Leishmania and other Trypanosomatidae display some peculiar features, which make them a complex system to study. Leishmaniasis chemotherapy is limited due to high toxicity of available drugs, long-term treatment protocols, and occurrence of drug resistant parasite strains. Systems biology studies the interactions and behavior of complex biological processes and may improve knowledge of Leishmania drug resistance. System-level studies to understand Leishmania biology have been challenging mainly because of its unusual molecular features. Networks integrating the biochemical and biological pathways involved in drug resistance have been reported in literature. Antioxidant defense enzymes have been identified as potential drug targets against leishmaniasis. These and other biomarkers might be studied from the perspective of systems biology and systems parasitology opening new frontiers for drug development and treatment of leishmaniasis and other diseases. Our main goals include: 1) Summarize current advances in Leishmania research focused on chemotherapy and drug resistance. 2) Share our viewpoint on the application of systems biology to Leishmania studies. 3) Provide insights and directions for future investigation.


Assuntos
Leishmania , Leishmaniose , Psychodidae , Animais , Resistência a Medicamentos , Humanos , Biologia de Sistemas
16.
Vaccine ; 39(20): 2755-2763, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33875268

RESUMO

In Brazil, canine visceral leishmaniasis is an important public health problem due to its alarming growth. The high prevalence of infected dogs reinforces the need for a vaccine for use in prophylactic vaccination campaigns. In the present study, we evaluate the immunogenicity and protection of the best dose of Chimera A selected through the screening of cytokines production important in disease. BALB/c mice were vaccinated subcutaneously with three doses and challenged intravenously with 1 × 107L. infantum promastigotes. Spleen samples were collected to assess the intracellular cytokine profile production, T cell proliferation and parasite load. At first, three different doses of Chimera A (5 µg, 10 µg and 20 µg) were evaluated through the production of IFN-γ and IL-10 cytokines. Since the dose of 20 µg showed the best results, it was chosen to continue the study. Secondarily, Chimera A at dose of 20 µg was formulated with Saponin plus Monophosphoryl lipid A. Vaccination with Chimera A alone and formulated with SM adjuvant system was able to increase the percentage of the proliferation of specific T lymphocytes and stimulated a Th1 response with increased levels of IFN-γ, TNF-α and IL-2, and decreased of IL-4 and IL-10. The vaccine efficacy through real-time PCR demonstrated a reduction in the splenic parasite load in animals that received Chimera A formulated with the SM adjuvant system (92%). Additionally, we observed increased levels of nitric oxide in stimulated-culture supernatants. The Chimera A formulated with the SM adjuvant system was potentially immunogenic, being able to induce immunoprotective mechanisms and reduce parasite load. Therefore, the use of T-cell multi-epitope vaccine is promising against visceral leishmaniasis.


Assuntos
Leishmania infantum , Vacinas contra Leishmaniose , Leishmaniose Visceral , Adjuvantes Imunológicos , Animais , Antígenos de Protozoários , Brasil , Citocinas , Cães , Leishmaniose Visceral/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C
17.
Parasitol Res ; 120(2): 679-692, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33415401

RESUMO

Owing to the importance and clinical diversity of Leishmania infantum, studying its virulence factors is promising for understanding the relationship between parasites and hosts. In the present study, differentially abundant proteins from strains with different degrees of virulence in promastigote and amastigote forms were compared using two quantitative proteomics techniques, differential gel electrophoresis and isobaric mass tag labeling, followed by identification by mass spectrometry. A total of 142 proteins were identified: 96 upregulated and 46 downregulated proteins in the most virulent strain compared to less virulent. The interaction between the proteins identified in each evolutionary form was predicted. The results showed that in the amastigote form of the most virulent strain, there was a large group of proteins related to glycolysis, heat shock, and ribosomal proteins, whereas in the promastigote form, the group consisted of stress response, heat shock, and ribosomal proteins. In addition, biological processes related to metabolic pathways, ribosomes, and oxidative phosphorylation were enriched in the most virulent strain (BH400). Finally, we noted several proteins previously found to play important roles in L. infantum infection, which showed increased abundance in the virulent strain, such as ribosomal proteins, HSP70, enolase, fructose 1,6-biphosphate aldolase, peroxidoxin, and tryparedoxin peroxidase, many of which interact with each other.


Assuntos
Leishmania infantum/metabolismo , Leishmania infantum/patogenicidade , Proteoma/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Leishmania infantum/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Proteômica , Virulência , Fatores de Virulência/metabolismo
18.
PLoS One ; 15(12): e0243840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33306749

RESUMO

Bone marrow (BM) is an organ responsible for crucial processes in living organs, e. g., hematopoiesis. In recent years, Organ-on-a-Chip (OoC) devices have been used to satisfy the need for in vitro systems that better mimic the phenomena occurring in the BM microenvironment. Given the growing interest in these systems and the diversity of developed devices, an integrative systematic literature review is required. We have performed this review, following the PRISMA method aiming to identify the main characteristics and assess the effectiveness of the devices that were developed to represent the BM. A search was performed in the Scopus, PubMed, Web of Science and Science Direct databases using the keywords (("bone marrow" OR "hematopoietic stem cells" OR "haematopoietic stem cells") AND ("organ in a" OR "lab on a chip" OR "microfluidic" OR "microfluidic*" OR ("bioreactor" AND "microfluidic*"))). Original research articles published between 2009 and 2020 were included in the review, giving a total of 21 papers. The analysis of these papers showed that their main purpose was to study BM cells biology, mimic BM niches, model pathological BM, and run drug assays. Regarding the fabrication protocols, we have observed that polydimethylsiloxane (PDMS) material and soft lithography method were the most commonly used. To reproduce the microenvironment of BM, most devices used the type I collagen and alginate. Peristaltic and syringe pumps were mostly used for device perfusion. Regarding the advantages compared to conventional methods, there were identified three groups of OoC devices: perfused 3D BM; co-cultured 3D BM; and perfused co-cultured 3D BM. Cellular behavior and mimicking their processes and responses were the mostly commonly studied parameters. The results have demonstrated the effectiveness of OoC devices for research purposes compared to conventional cell cultures. Furthermore, the devices have a wide range of applicability and the potential to be explored.


Assuntos
Biomimética/métodos , Medula Óssea/fisiologia , Dispositivos Lab-On-A-Chip , Microfluídica , Animais , Materiais Biocompatíveis/farmacologia , Humanos
19.
Parasit Vectors ; 13(1): 600, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256787

RESUMO

BACKGROUND: One of the major challenges to leishmaniasis treatment is the emergence of parasites resistant to antimony. To study differentially expressed genes associated with drug resistance, we performed a comparative transcriptomic analysis between wild-type and potassium antimonyl tartrate (SbIII)-resistant Leishmania infantum lines using high-throughput RNA sequencing. METHODS: All the cDNA libraries were constructed from promastigote forms of each line, sequenced and analyzed using STAR for mapping the reads against the reference genome (L. infantum JPCM5) and DESeq2 for differential expression statistical analyses. All the genes were functionally annotated using sequence similarity search. RESULTS: The analytical pipeline considering an adjusted p-value < 0.05 and fold change > 2.0 identified 933 transcripts differentially expressed (DE) between wild-type and SbIII-resistant L. infantum lines. Out of 933 DE transcripts, 504 presented functional annotation and 429 were assigned as hypothetical proteins. A total of 837 transcripts were upregulated and 96 were downregulated in the SbIII-resistant L. infantum line. Using this DE dataset, the proteins were further grouped in functional classes according to the gene ontology database. The functional enrichment analysis for biological processes showed that the upregulated transcripts in the SbIII-resistant line are associated with protein phosphorylation, microtubule-based movement, ubiquitination, host-parasite interaction, cellular process and other categories. The downregulated transcripts in the SbIII-resistant line are assigned in the GO categories: ribonucleoprotein complex, ribosome biogenesis, rRNA processing, nucleosome assembly and translation. CONCLUSIONS: The transcriptomic profile of L. infantum showed a robust set of genes from different metabolic pathways associated with the antimony resistance phenotype in this parasite. Our results address the complex and multifactorial antimony resistance mechanisms in Leishmania, identifying several candidate genes that may be further evaluated as molecular targets for chemotherapy of leishmaniasis.


Assuntos
Antimônio/farmacologia , Antiprotozoários/farmacologia , Resistência a Medicamentos , Leishmania infantum/efeitos dos fármacos , Leishmania infantum/genética , Proteínas de Protozoários/genética , Animais , Leishmania infantum/metabolismo , Leishmania infantum/fisiologia , Proteínas de Protozoários/metabolismo , Transcriptoma/efeitos dos fármacos
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