RESUMO
The coronavirus infectious disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has been spreading rapidly worldwide, creating a pandemic. This article describes the evaluation of the antiviral activity of nordihydroguaiaretic acid (NDGA), a molecule found in Creosote bush (Larrea tridentata) leaves, against SARS-CoV-2 in vitro. A 35 µM concentration of NDGA was not toxic to Vero cells and exhibited a remarkable inhibitory effect on the SARS-CoV-2 cytopathic effect, viral plaque formation, RNA replication, and expression of the SARS-CoV-2 spike glycoprotein. The 50% effective concentration for NDGA was as low as 16.97 µM. Our results show that NDGA could be a promising therapeutic candidate against SARS-CoV-2.
Assuntos
COVID-19 , SARS-CoV-2 , Animais , Chlorocebus aethiops , Masoprocol/farmacologia , Masoprocol/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Células VeroRESUMO
Canine parvovirus type 2 (CPV-2) infection in dogs is associated with severe gastroenteritis, bloody diarrhea, and vomiting, resulting in high rates of death, especially in unvaccinated puppies within the first months of age. There are three variants, called CPV-2a, CPV-2b, and CPV-2c, co-circulating worldwide. Our group previously reported that the only circulating CPV-2 variant in the Guadalajara metropolitan area in western Mexico was type 2c. Now, a five-year study was performed in order to investigate the possible dominance of CPV-2c in our region. Rectal swabs were collected from 146 dogs with clinical gastroenteritis from May 2014 to August 2019 at the Veterinary Hospital of the University of Guadalajara. Of these, 90 dogs tested positive for canine parvovirus by PCR. Most of the infected dogs with CPV-2 had a partial or incomplete vaccination status (n = 88, 97.8%). Approximately 65% (n = 59) of them were mixed-breed dogs, 77.8% (n = 70) were under 6 months of age, and 37.8% (n = 34) of them died from clinical complications. RFLP analysis of amplicons derived from the vp2 gene showed that all 90 DNA samples corresponded to CPV-2c, with no evidence of the presence of CPV-2a or CPV-2b variants. Twenty-nine of the 90 DNA samples were selected for amplification of a portion of the vp2 gene, and sequencing of these amplicons showed that all of them had the sequence GAA at codon 426, encoding the amino acid glutamic acid, which is characteristic of CPV-2c. Phylogenetic analysis showed that the CPV-2c sequences were related to those of viruses from Europe and South America. The present study indicates that CPV-2c is still the only variant circulating in the dog population of the Guadalajara metropolitan area.
Assuntos
Doenças do Cão , Gastroenterite , Infecções por Parvoviridae , Parvovirus Canino , Animais , Códon , Doenças do Cão/epidemiologia , Cães , Gastroenterite/epidemiologia , Gastroenterite/genética , Gastroenterite/veterinária , Ácido Glutâmico/genética , México/epidemiologia , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Filogenia , Melhoramento VegetalRESUMO
Virus-like particles are excellent inducers of the adaptive immune response of humans and are presently being used as scaffolds for the presentation of foreign peptides and antigens derived from infectious microorganisms for subunit vaccine development. The most common approaches for peptide and antigen presentation are translational fusions and chemical coupling, but some alternatives that seek to simplify the coupling process have been reported recently. In this work, an alternative platform for coupling full antigens to virus-like particles is presented. Heterodimerization motifs inserted in both Tobacco etch virus coat protein and green fluorescent protein directed the coupling process by simple mixing, and the obtained complexes were easily taken up by a macrophage cell line.
Assuntos
Apresentação de Antígeno/imunologia , Antígenos , Potyvirus , Vacinas de Partículas Semelhantes a Vírus , Animais , Antígenos/química , Antígenos/imunologia , Camundongos , Potyvirus/química , Potyvirus/imunologia , Células RAW 264.7 , Vacinas de Partículas Semelhantes a Vírus/química , Vacinas de Partículas Semelhantes a Vírus/imunologiaRESUMO
Abstract Zika virus (ZIKV) has gained great importance worldwide since the past epidemic that occurred in 2015 in Brazil. Early identification of ZIKV is critical to minimize transmission and prevents potentially devastating consequences, including microcephaly in neonates of infected women, congenital blindness, or Guillain-Barré Syndrome. However, this is not an easy task, considering that approximately 80% of ZIKV infection cases are asymptomatic or oligosymptomatic, there are diverse modes of transmission (vertical transmission is through vectors and horizontal transmission through blood, saliva, semen, and urine from infected people), and the fact that ZIKV has a high identity percentage with other cocirculating Flaviviruses such as dengue. Here, we review ZIKV diagnostic methods, with special emphasis on the development of point-of-care diagnostic assays, since these devices commonly have two important advantages: they provide prompt screening and are affordable.
Assuntos
Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Infecção por Zika virus/diagnósticoRESUMO
Zika virus (ZIKV) has gained great importance worldwide since the past epidemic that occurred in 2015 in Brazil. Early identification of ZIKV is critical to minimize transmission and prevents potentially devastating consequences, including microcephaly in neonates of infected women, congenital blindness, or Guillain-Barré Syndrome. However, this is not an easy task, considering that approximately 80% of ZIKV infection cases are asymptomatic or oligosymptomatic, there are diverse modes of transmission (vertical transmission is through vectors and horizontal transmission through blood, saliva, semen, and urine from infected people), and the fact that ZIKV has a high identity percentage with other cocirculating Flaviviruses such as dengue. Here, we review ZIKV diagnostic methods, with special emphasis on the development of point-of-care diagnostic assays, since these devices commonly have two important advantages: they provide prompt screening and are affordable.
Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Infecção por Zika virus/diagnóstico , HumanosRESUMO
Background: Several studies have shown that patients with cancer have antibodies in serum that react with cellular autoantigens, known as Tumor-Associated Antigens (TAA). The present work aimed to determine whether a mini-array comprising four recombinant TAA increases the detection of specific serum antibodies for the diagnosis of early-stage breast cancer. Methods: The mini-array included Alpha 1-AntiTrypsin (A1AT), TriosePhosphate Isomerase 1 (TPI1), Peptidyl-Prolyl cis-trans Isomerase A (PPIA), and PeroxiReDoXin 2 (PRDX2) full-length recombinant proteins. The proteins were produced after gene cloning, expression, and purification, and were verified by Western blot assays. Then, Dot-Blot was performed to find antibodies against the four TAA in 12 sera from women with early-stage breast cancer (stage II) and 12 sera from healthy women. Results: Antibody detection against individual TAA in early-stage breast cancer sera ranged from 58.3% to 83.3%. However, evaluation of the four TAA showed that there was a positive antibody reaction reaching a sensitivity of 100% and a specificity of 85% in early-stage breast cancer, suggesting that this mini-array must be evaluated as a clinical diagnostic tool for early-stage breast cancer in a larger sample size. Conclusion: Our results suggest that TAA mini-arrays may provide a promising and powerful method for improving the detection of breast cancer in Mexican women.
Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais , Neoplasias da Mama/diagnóstico , Soro/química , Adulto , Antígenos de Neoplasias , Neoplasias da Mama/sangue , Feminino , Testes Hematológicos , Humanos , Pessoa de Meia-IdadeRESUMO
The prediction of regulatory single nucleotide polymorphisms (rSNPs) in proximal promoters of disease-related genes could be a useful tool for personalized medicine in both patient stratification and customized therapy. Using our previously reported method of rSNPs prediction (currently a software called SNPClinic v.1.0) as well as with PredictSNP tool, we performed in silico prediction of regulatory SNPs in the antimicrobial peptide human ß-defensin 1 gene in three human cell lines from 1,000 Genomes Project (1kGP), namely A549 (epithelial cell line), HL-60 (neutrophils) and TH 1 (lymphocytes). These predictions were run in a proximal pseudo-promoter comprising all common alleles on each polymorphic site according to the 1,000 Genomes Project data (1kGP: ALL). Plasmid vectors containing either the major or the minor allele of a putative rSNP rs5743417 (categorized as regulatory by SNPClinic and confirmed by PredictSNP) and a non-rSNP negative control were transfected to lung A549 human epithelial cell line. We assessed functionality of rSNPs by qPCR using the Pfaffl method. In A549 cells, minor allele of the SNP rs5743417 GâA showed a significant reduction in gene expression, diminishing DEFB1 transcription by 33% when compared with the G major allele (p-value = .03). SNP rs5743417 minor allele has high frequency in Gambians (8%, 1kGP population: GWD) and Afro-Americans (3.3%, 1kGP population: ASW). This SNP alters three transcription factors binding sites (TFBSs) comprising SREBP2 (sterols and haematopoietic pathways), CREB1 (cAMP, insulin and TNF pathways) and JUND (apoptosis, senescence and stress pathways) in the proximal promoter of DEFB1. Further in silico analysis reveals that this SNP also overlaps with GS1-24F4.2, a lincRNA gene complementary to the X Kell blood group related 5 (XKR5) mRNA. The potential clinical impact of the altered constitutive expression of DEFB1 caused by rSNP rs5743417 in DEFB1-associated diseases as tuberculosis, COPD, asthma, cystic fibrosis and cancer in African and Afro-American populations deserves further research.
Assuntos
Polimorfismo de Nucleotídeo Único/genética , Proteínas Citotóxicas Formadoras de Poros/genética , Regiões Promotoras Genéticas/genética , beta-Defensinas/genética , Células A549 , Negro ou Afro-Americano/genética , Sítios de Ligação , População Negra/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Regulação da Expressão Gênica/genética , Humanos , Linfócitos/metabolismo , Neutrófilos/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , RNA Mensageiro/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/genéticaRESUMO
Zika virus (ZIKV) is a mosquito-borne pathogen discovered in the late 40's in Uganda during a surveillance program for yellow fever. By 2014 the virus reached Eastern Island in the Americas, and two years later, the virus spread to almost all countries and territories of the Americas. The mosquito Aedes aegypti has been identified as the main vector of the disease, and several researchers have also studied the vector competence of Culex quinquefasciatus in virus transmission. The aim of the present study was to evaluate the vector competence of Ae. aegypti and Cx. quinquefasciatus in order to understand their roles in the transmission of ZIKV in Guadalajara, Jalisco, Mexico. In blood feeding laboratry experiments, we found that Ae. aegypti mosquitoes showed to be a competent vector able to transmit ZIKV in this area. On the other hand, we found that F0 Cx. quinquefasciatus mosquitoes are refractory to ZIKV infection, dissemination and transmission.
Assuntos
Aedes/virologia , Culex/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/transmissão , Zika virus , Animais , Cidades , Feminino , Saliva/virologia , Carga ViralRESUMO
Carica papaya latex is one of the most studied sources of plant lipases. However, the complexity of the matrix composition makes it difficult to isolate and purify the lipolytic enzymes present in Carica papaya latex. Therefore, diverse strategies have been developed to study the catalytic properties of these enzymes.Recently the first lipase from Carica papaya latex (CpLip1) has been successfully cloned and expressed in order to study their catalytic properties. In order to improve the catalytic properties and increase the potential for its use at industrial scale.In this chapter, a practical protocol to recombinant CpLip1 lipase is given.
Assuntos
Carica/enzimologia , Expressão Gênica , Lipase/metabolismo , Ácidos e Sais Biliares/farmacologia , Carica/genética , Ativação Enzimática/efeitos dos fármacos , Lipase/genéticaRESUMO
Bovine colostrum contains compounds, which provide passive immune protection from mother to newborn calves. Little is known about cytokine levels and their role in bovine colostrum. Moreover, the capacity of bovine colostrum cells to mount specific immune responses after natural exposure to bovine tuberculosis (bTB) antigens in dairy herds has not been studied, thus far. The purpose of this study was to identify biomarkers for bTB infection measurable in bovine colostrum. The present study reveals that isolated-immune colostrum cells can mount a specific immune response against bTB antigens, by measuring the novo IFN-γ release in cell culture. We found that IFN-γ levels in the responders (Bov+) to bTB antigen were higher than in non-responders (Bov-). On the other hand, proinflammatory cytokines contained in colostrum's whey were tested in Tuberculin Skin Test (TST) reactor (TST+) and non-reactor (TST-) animals to assess their potential role as biomarker. We observed that IFN-γ levels were lower or undetectable, as opposed to IL4 levels were measurable, the TNF-α level was higher in TST- than TST+, while IL-6 levels showed the opposite reaction and with no statistical significance. Moreover, IL-1α mRNA expression levels were higher in colostrum mononuclear cells (CMC) in Bov+ cattle. Collectively, these data suggest that the differential expression of pro and anti-inflammatory cytokines could have relevant value to diagnose bTB in cattle.
Assuntos
Biomarcadores , Colostro/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Mycobacterium bovis/imunologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/metabolismo , Animais , Antígenos de Bactérias/imunologia , Bovinos , Citocinas/genética , Feminino , Expressão Gênica , Testes de Liberação de Interferon-gama , Tuberculose Bovina/genéticaRESUMO
BACKGROUND: Assembly of recombinant capsid proteins into virus-like particles (VLPs) still represents an interesting challenge in virus-based nanotechnologies. The structure of VLPs has gained importance for the development and design of new adjuvants and antigen carriers. The potential of Tobacco etch virus capsid protein (TEV CP) as adjuvant has not been evaluated to date. FINDINGS: Two constructs for TEV CP expression in Escherichia coli were generated: a wild-type version (TEV-CP) and a C-terminal hexahistidine (His)-tagged version (His-TEV-CP). Although both versions were expressed in the soluble fraction of E. coli lysates, only His-TEV-CP self-assembled into micrometric flexuous filamentous VLPs. In addition, the His-tag enabled high yields and facilitated purification of TEV VLPs. These TEV VLPs elicited broader IgG2-specific antibody response against a novel porcine reproductive and respiratory syndrome virus (PRRSV) protein when compared to the potent IgG1 response induced by the protein alone. CONCLUSIONS: His-TEV CP was purified by immobilized metal affinity chromatography and assembled into VLPs, some of them reaching 2-µm length. TEV VLPs administered along with PRRSV chimeric protein changed the IgG2/IgG1 ratio against the chimeric protein, suggesting that TEV CP can modulate the immune response against a soluble antigen.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/administração & dosagem , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Potyvirus/imunologia , Vacinas Virais/imunologia , Virossomos/administração & dosagem , Citoesqueleto de Actina/metabolismo , Adjuvantes Imunológicos/metabolismo , Proteínas do Capsídeo/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Imunoglobulina G/sangue , Multimerização Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Virossomos/metabolismoRESUMO
MAIN CONCLUSION: The HRA2pl peptide expressed by transient transformation in N. tabacum plants is capable of inhibiting the binding of the human metapneumovirus to HEp-2 cells at the fusion stage. Human metapneumovirus (hMPV) is an agent responsible for acute respiratory infections that mainly affects children under 3 years, the elderly and immunocompromised patients. In children younger than 5 years, respiratory tract infections account for 20 % of deaths worldwide. However, there is currently no treatment or vaccine available against hMPV. The production of a safe, efficient and low cost treatment against this virus is a current challenge. Plants provide a system for recombinant protein production that is cost effective and is easier to scale up to an industrial level than other platforms; in addition, the plant tissue may be used as raw food, dried or, alternatively, proteins may be partially or fully purified and administered in aerosol or capsules as dry powder. In this study, we designed a gene expressing an antiviral peptide against hMPV based on the heptad repeat A domain of the F protein of the virus. We produced the recombinant peptide by a viral transient expression system (Magnifection(®)) in Nicotiana tabacum plants. The efficacy of this antiviral peptide was confirmed by in vitro assays in HEp-2 cell line. This is a promising result that can offer a prophylactic approach against hMPV.
Assuntos
Antivirais/química , Metapneumovirus/fisiologia , Nicotiana/genética , Peptídeos/farmacologia , Transformação Genética , Internalização do Vírus/efeitos dos fármacos , Sequência de Aminoácidos , Antivirais/farmacologia , Bioensaio , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Metapneumovirus/efeitos dos fármacos , Dados de Sequência Molecular , Infecções por Paramyxoviridae/patologia , Infecções por Paramyxoviridae/virologia , Peptídeos/química , Plantas Geneticamente Modificadas , Transformação Genética/efeitos dos fármacosRESUMO
Rhipicephalus (Boophilus) microplus is an obligate haematophagous arthropod and the major problem for cattle industry due to economic losses it causes. The parasite shows a remarkable adaptability to changing environmental conditions as well as an exceptional ability to survive long-term starvation. This ability has been related to a process of intracellular protein degradation called autophagy. This process in ticks is still poorly understood and only few autophagy-related (ATG) genes have been characterized. The aim of the present study was to examine the ESTs database, BmiGI, of R. microplus searching for ATG homologues. We predicted five putative ATG genes, ATG3, ATG4, ATG6 and two ATG8s. Further characterization led to the identification of RmATG8a and RmATG8b, homologues of GABARAP and MAP1LC3, respectively, and both of them belonging to the ATG8 family. PCR analyses showed that the expression level of RmATG8a and RmATG8b was higher in egg and larval stages when compared to ovary and midgut from adult ticks. This up-regulation coincides with the period in which ticks are in a starvation state, suggesting that autophagy is active in R. microplus.
Assuntos
Bovinos/parasitologia , Rhipicephalus/genética , Sequência de Aminoácidos , Animais , Autofagia/genética , Sequência de Bases , Clonagem Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA/química , RNA/genética , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
This study combines two methodologies - vector expression of a genomic library and proteomics - to identify immunogenic proteins of Mycobacterium bovis. Immunization of BALB/c mice with a plasmid DNA pool from the library, containing approximately 8000 clones, induced a humoral response that facilitated the detection of 12 antigenic proteins by Western blotting. Two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometry identified four proteins (Cpn60-1, HSP70, EF-Tu, and AdoHcyase). Such genomic immunization offers the possibility of in vivo screening of potential candidate M. bovis antigens.
Assuntos
Antígenos de Bactérias/genética , DNA Bacteriano/genética , Biblioteca Genômica , Mycobacterium bovis/genética , Proteômica/métodos , Tuberculose Bovina/diagnóstico , Animais , Antígenos de Bactérias/imunologia , Western Blotting/veterinária , Bovinos , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida/veterinária , Espectrometria de Massas/veterinária , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis/imunologia , Tuberculose Bovina/genética , Tuberculose Bovina/imunologiaRESUMO
Low phosphorus (P) availability is one of the most limiting factors for plant productivity in many natural and agricultural ecosystems. Plants display a wide range of adaptive responses to cope with low P stress, which generally serve to enhance P availability in the soil and to increase its uptake by roots. In Arabidopsis (Arabidopsis thaliana), primary root growth inhibition and increased lateral root formation have been reported to occur in response to P limitation. To gain knowledge of the genetic mechanisms that regulate root architectural responses to P availability, we designed a screen for identifying Arabidopsis mutants that fail to arrest primary root growth when grown under low P conditions. Eleven low phosphorus insensitive (lpi) mutants that define at least four different complementation groups involved in primary root growth responses to P availability were identified. The lpi mutants do not show the typical determinate developmental program induced by P stress in the primary root. Other root developmental aspects of the low P rescue system, including increased root hair elongation and anthocyanin accumulation, remained unaltered in lpi mutants. In addition to the insensitivity of primary root growth inhibition, when subjected to P deprivation, lpi mutants show a reduced induction in the expression of several genes involved in the P starvation rescue system (PHOSPHATE TRANSPORTER 1 and 2, PURPLE ACID PHOSPHATASE 1, ACID PHOSPHATASE 5, and INDUCED BY PHOSPHATE STARVATION 1). Our results provide genetic support for the role of P as an important signal for postembryonic root development and root meristem maintenance and show a crosstalk in developmental and biochemical responses to P deprivation.