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BACKGROUND: Humoral immune response against the pre-fusion (pre-F) conformation of respiratory syncytial virus (RSV) F protein has been proposed to play a protective role against infection. An RSV pre-F maternal vaccine has been recently approved in several countries to protect young infants against RSV. We aimed to assess serum IgG titers against the pre-F and post-F conformations of RSV F protein and their association with life-threatening RSV disease (LTD) in previously healthy infants. METHODS: A prospective cohort study including hospitalized infants <12 months with a first RSV infection was conducted during 2017-2019. Patients with LTD required intensive care and mechanical respiratory assistance. RSV pre-F exclusive and post-F antibody responses were determined by post-F competition and non-competition immunoassays, respectively, and neutralizing activity was measured by plaque reduction neutralization test. RESULTS: Fifty-eight patients were included; the median age was 3.5 months and 41 % were females. Fifteen patients developed LTD. RSV F-specific antibody titers positively correlated with neutralizing antibody titers in acute and convalescent phases but, importantly, they did not associate with LTD. Acute RSV pre-F exclusive and post-F IgG titers negatively correlated with patient age (P = 0.0007 and P < 0.0001), while a positive correlation was observed between the fold changes in RSV F-specific antibody titers between convalescent and acute phase and patient age (P = 0.0014 and P < 0.0001). Infants ≤2 months exhibited significantly lower fold-changes in RSV F-specific and neutralizing antibody titers between convalescence and acute phase than older infants. Additionally, acute RSV antibody titers showed no correlation with nasal RSV load and, furthermore, nasal viral load was not associated with the development of LTD. CONCLUSIONS: This study highlights that protection against life-threatening RSV disease is not necessarily antibody-dependent. Further characterization of the immune response against RSV and its role in protection against severe disease is important for the development of the safest possible preventive strategies.
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Anticorpos Neutralizantes , Anticorpos Antivirais , Imunoglobulina G , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Proteínas Virais de Fusão , Humanos , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Feminino , Lactente , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Proteínas Virais de Fusão/imunologia , Estudos Prospectivos , Vírus Sincicial Respiratório Humano/imunologia , Masculino , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Conformação Proteica , Vacinas contra Vírus Sincicial Respiratório/imunologia , Recém-NascidoRESUMO
The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a key vector of the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) associated with huanglongbing (HLB), the most serious and currently incurable disease of citrus worldwide. Here we report the first investigation into the potential use of a spider venom-derived recombinant neurotoxin, ω/κ-HxTx-Hv1h (hereafter HxTx-Hv1h) when delivered alone or when fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) to control D. citri. Proteins, including GNA alone, were purified from fermented transformed yeast Pichia pastoris cultures. Recombinant HxTx-Hv1h, HxTx-Hv1h/GNA and GNA were all orally toxic to D. citri, with Day 5 median lethal concentrations (LC50) derived from dose-response artificial diet assays of 27, 20 and 52 µM, respectively. Western analysis of whole insect protein extracts confirmed that psyllid mortality was attributable to protein ingestion and that the fusion protein was stable to cleavage by D. citri proteases. When applied topically (either via droplet or spray) HxTx-Hv1h/GNA was the most effective of the proteins causing >70 % mortality 5 days post treatment, some 2 to 3-fold higher levels of mortality as compared to the toxin alone. By contrast, no significant mortality or phenotypic effects were observed for bumble bees (Bombus terrestris L.) fed on the recombinant proteins in acute toxicity assays. This suggests that HxTx-Hv1h/GNA has potential as a novel bioinsecticide for the management of D. citri offering both enhanced target specificity as compared to chemical pesticides and compatibility with integrated pest management (IPM) strategies.
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Citrus , Hemípteros , Liberibacter , Animais , Hemípteros/fisiologia , Neurotoxinas , Citrus/microbiologia , Doenças das Plantas/microbiologiaRESUMO
Despite SARS-CoV-2 being a "novel" virus, early detection of anti-spike IgG in severe COVID-19 patients may be caused by the amplification of humoral memory responses against seasonal coronaviruses. Here, we examine this phenomenon by characterizing anti-spike IgG responses in non-hospitalized convalescent individuals across a spectrum of COVID-19 severity. We observe that disease severity positively correlates with anti-spike IgG levels, IgG cross-reactivity against other betacoronaviruses (ß-CoVs), and FcγR activation. Analysis of IgG targeting ß-CoV-conserved and non-conserved immunodominant epitopes within the SARS-CoV-2 spike protein revealed epitope-specific relationships: IgG targeting the conserved heptad repeat (HR) 2 region significantly correlates with milder disease, while targeting the conserved S2'FP region correlates with more severe disease. Furthermore, a lower HR2-to-S2'FP IgG-binding ratio correlates with greater disease severity, with ICU-hospitalized COVID-19 patients showing the lowest HR2/S2'FP ratios. These findings suggest that HR2/S2'FP IgG profiles may predict disease severity and offer insight into protective versus deleterious humoral recall responses.
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COVID-19 , SARS-CoV-2 , Humanos , Imunoglobulina G , Estações do Ano , Glicoproteína da Espícula de CoronavírusRESUMO
Chimeric virus-like particles are self-assembling structures composed of viral proteins that had been modified to incorporate sequences from different organisms, being able to trigger immune responses against the heterologous sequence. However, the identification of suitable sites for that purpose in the carrier protein is not an easy task. In this work, we describe the generation of rabies chimeric VLPs that expose a major antigenic site of foot-and-mouth disease virus (FMDV) by identifying suitable regions in rabies glycoprotein (RVG), as a proof of concept of a novel heterologous display platform for vaccine applications. To identify adequate sites for insertion of heterologous sequences without altering the correct folding of RVG, we identified regions that were evolutionally non-conserved in Lyssavirus glycoproteins and performed a structural analysis of those regions using a 3D model of RVG trimer that we generated. The heterologous sequence was inserted in three different sites within RVG sequence. In every case, it did not affect the correct folding of the protein and was surface exposed, being recognized by anti-FMDV antibodies in expressing cells as well as in the surface of VLPs. This work sets the base for the development of a heterologous antigen display platform based on rabies VLPs. KEY POINTS: ⢠Adequate regions for foreign epitope display in RVG were found. ⢠G-H loop of FMDV was inserted in three regions of RVG. ⢠The foreign epitope was detected by specific antibodies on fusion proteins. ⢠G-H loop was detected on the surface of chimeric VLPs.
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Vírus da Febre Aftosa , Febre Aftosa , Raiva , Vacinas , Animais , Anticorpos Antivirais , Vírus da Febre Aftosa/genética , Glicoproteínas/genéticaRESUMO
Biological drugs or biopharmaceuticals off patent open a large market for biosimilars and biobetters, follow-on biologics. Biobetters, in particular, are new drugs designed from existing ones with improved properties such as higher selectivity, stability, half-life and/or lower toxicity/immunogenicity. Glycosylation is one of the most used strategies to improve biological drugs, nonetheless bioconjugation is an additional alternative and refers to the covalent attachment of polymers to biological drugs. Extensive research on novel polymers is underway, nonetheless PEGylation is still the best alternative with the longest clinical track record. Innovative trends based on genetic engineering techniques such as fusion proteins and PASylation are also promising. In this review, all these alternatives wereexplored as well as current market trends, legislation and future perspectives.
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Produtos Biológicos , Medicamentos Biossimilares , Produtos Biológicos/farmacologia , Produtos Biológicos/normas , Medicamentos Biossimilares/farmacologia , Medicamentos Biossimilares/normas , Tratamento Farmacológico/tendências , Humanos , Engenharia Metabólica/métodos , Engenharia de Proteínas/métodos , Melhoria de QualidadeRESUMO
Rhizobium adhering proteins or 'Raps' are secreted proteins identified in a very restricted group of rhizobial strains, specifically those belonging to R. leguminosarum and R. etli. The distinctive feature of members of the Rap family is the presence of one or two cadherin-like domains or CHDLs that are also present in numerous extracellular bacterial and archaeal proteins and were proposed to confer carbohydrate binding ability. We have previously made an in-depth characterization of RapA2, a calcium-binding lectin, composed by two CHDLs, involved in biofilm matrix remodelling in R. leguminosarum bv. viciae 3841. In this study, CHDLs derived from RapA2 were analysed in detail, finding significant structural and functional differences despite their considerable sequence similarity. Only the carboxy-terminal CHDL retained properties similar to those displayed by RapA2. Our findings were used to obtain a novel fluorescent probe to study biofilm matrix development by confocal laser scanning microscopy, and also to shed some light on the role of the ubiquitous CHDL domains in bacterial secreted proteins.
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Rhizobium leguminosarum , Rhizobium , Rhizobium/metabolismo , Caderinas/metabolismo , Proteínas de Fluorescência Verde , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Proteínas de Bactérias/metabolismoRESUMO
Abstract The present study deals with the computational design and analysis of a novel fusion protein based on a single chain variable fragment that binds to the extracellular domain of human epidermal growth factor receptor 2 (HER2) in breast cancer cells. Alpha luffin, a small ribosome inactivating protein (RIP), was attached to the anti-HER2 antibody fragment. I-TASSER modeling provided the full-length structure of the fusion protein. Molecular docking evaluated the molecular interactions of the complementarity-determining regions of designed fusion protein to HER2. Energy minimization and molecular dynamics simulations were conducted to refine the complexes. RMSD plot revealed reasonable stability of the fusion protein during the simulation. The free binding energy profile of complexes affirmed a favorable binding affinity of proteins in complex with HER2 using molecular mechanics Poisson-Boltzmann surface area (G-MMPBSA) algorithm. In general, this approach looks promising in the development of new fusion proteins in terms of immunotoxins with appropriate cytotoxicity.
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Plant 90kDa heat shock protein (HSP90) is a potent adjuvant that increases both humoral and cellular immune responses to diverse proteins and peptides. In this study, we explored whether Arabidopsis thaliana HSP90 (AtHsp81.2) can improve the immune effects of a Toxoplasma gondii surface antigen 1 (SAG1). We designed two constructs containing the sequence of mature antigen (SAG1m), from aa77 to aa322, and B- and T-cell antigenic epitope-containing SAG1HC, from aa221 to aa319 fused to AtHsp81.2 sequence. When comparing the transient expression in Nicotiana tabacum X-27-8 leaves, which overexpress the suppressor helper component protease HC-Pro-tobacco etch virus (TEV), to that in N. benthamiana leaves, co-agroinfiltrated with the suppressor p19, optimal conditions included 6-week-old N. benthamiana plants, 7-day time to harvest, Agrobacterium tumefaciens cultures with an OD600nm of 0.6 for binary vectors and LED lights. While AtHsp81.2-SAG1m fusion protein was undetectable by Western blot in any of the evaluated conditions, AtHsp81.2-SAG1HC was expressed as intact fusion protein, yielding up to 90µg/g of fresh weight. Besides, the AtHsp81.2-SAG1HC mRNA was strongly expressed compared to the endogenous Nicotiana tabacum elongation factor-alpha (NtEFα) gene, whereas the AtHsp81.2-SAG1m mRNA was almost undetectable. Finally, mice were orally immunized with AtHsp81.2-SAG1HC-infiltrated fresh leaves (plAtHsp81.2-SAG1HC group), recombinant AtHsp81.2-SAG1HC purified from infiltrated leaves (rAtHsp81.2-SAG1HC group), non-infiltrated fresh leaves (control group), or phosphate-buffered saline (PBS group). Serum samples from plAtHsp81.2-SAG1HC-immunized mice had significantly higher levels of IgGt, IgG2a, and IgG2b anti-SAG1HC antibodies than serum from rAtHsp81.2-SAG1HC, control, and PBS groups. The number of cysts per brain in the plAtHsp81.2-SAG1HC-immunized mice was significantly reduced, and the parasite load in brain tissue was also lower in this group compared with the remaining groups. In an immunoblot assay, plant-expressed AtHsp81.2-SAG1HC was shown to react with antibodies present in sera from T. gondii-infected people. Therefore, the plant expression of a T. gondii antigen fused to the non-pathogenic adjuvant and carrier plant HSP90 as formulations against T. gondii can improve the vaccine efficacy, and plant extract can be directly used for vaccination without the need to purify the protein, making this platform a suitable and powerful biotechnological system for immunogenic antigen expression against toxoplasmosis.
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We describe, for the first time, a new splice variant of the human TGF-ß type II receptor (TßRII). The new transcript lacks 149 nucleotides, resulting in a frameshift and the emergence of an early stop codon, rendering a truncated mature protein of 57 amino acids. The predicted protein, lacking the transmembrane domain and with a distinctive 13-amino-acid stretch at its C-terminus, was named TßRII-Soluble Endogenous (TßRII-SE). Binding predictions indicate that the novel 13-amino-acid stretch interacts with all three TGF-ß cognate ligands and generates a more extensive protein-protein interface than TßRII. TßRII-SE and human IgG1 Fc domain were fused in frame in a lentiviral vector (Lv) for further characterization. With this vector, we transduced 293T cells and purified TßRII-SE/Fc by A/G protein chromatography from conditioned medium. Immunoblotting revealed homogeneous bands of approximately 37 kDa (reduced) and 75 kDa (non-reduced), indicating that TßRII-SE/Fc is secreted as a disulfide-linked homodimer. Moreover, high-affinity binding of TßRII-SE to the three TGF-ß isoforms was confirmed by surface plasmon resonance (SPR) analysis. Also, intrahepatic delivery of Lv.TßRII-SE/Fc in a carbon tetrachloride-induced liver fibrosis model revealed amelioration of liver injury and fibrosis. Our results indicate that TßRII-SE is a novel member of the TGF-ß signaling pathway with distinctive characteristics. This novel protein offers an alternative for the prevention and treatment of pathologies caused by the overproduction of TGF-ß ligands.
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Translation engineering and bioinformatics have accelerated the rate at which gene sequences can be improved to generate multi-epitope proteins. Strong antigenic proteins for tuberculosis diagnosis include individual ESAT6 and CFP10 proteins or derived peptides. Obtention of heterologous multi-component antigens in E. coli without forming inclusion bodies remain a biotechnological challenge. The gene sequence for ESAT6-CFP10 fusion antigen was optimized by codon bias adjust for high-level expression as a soluble protein. The obtained fusion protein of 23.7 kDa was observed by SDS-PAGE and Western blot analysis after Ni-affinity chromatography and the yield of expressed soluble protein reached a concentration of approximately 67 mg/L in shake flask culture after IPTG induction. Antigenicity was evaluated at 4 µg/mL in whole blood cultures from bovines, and protein stimuli were assessed using a specific in vitro IFN-γ release assay. The hybrid protein was able to stimulate T-cell specific responses of bovine TB suspects. The results indicate that improved E. coli codon usage is a good and cost-effective strategy to potentialize large scale production of multi-epitope proteins with sustained antigenic properties for diagnostic purposes.
Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Mycobacterium bovis/imunologia , Fragmentos de Peptídeos/genética , Proteínas Recombinantes de Fusão/administração & dosagem , Vacinas contra a Tuberculose/administração & dosagem , Tuberculose Bovina/prevenção & controle , Sequência de Aminoácidos , Animais , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Bovinos , Clonagem Molecular , Códon , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Histidina/genética , Histidina/metabolismo , Imunogenicidade da Vacina , Interferon gama/biossíntese , Mycobacterium bovis/química , Mycobacterium bovis/genética , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Alinhamento de Sequência , Vacinas contra a Tuberculose/genética , Vacinas contra a Tuberculose/imunologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/microbiologia , Vacinação/métodosRESUMO
This study aimed to produce and characterize a recombinant Kluyveromyces sp. ß-galactosidase fused to a cellulose-binding domain (CBD) for industrial application. In expression assays, the highest enzymatic activities occurred after 48 h induction on Escherichia coli C41(DE3) strain at 20 °C in Terrific Broth (TB) culture medium, using isopropyl ß-d-1-thiogalactopyranoside (IPTG) 0.5 mM (108.77 U/mL) or lactose 5 g/L (93.10 U/mL) as inducers. Cultures at bioreactor scale indicated that higher product yield values in relation to biomass (2000 U/g) and productivity (0.72 U/mL.h) were obtained in culture media containing higher protein concentration. The recombinant enzyme showed high binding affinity to nanocellulose, reaching both immobilization yield and efficiency values of approximately 70% at pH 7.0 after 10 min reaction. The results of the present study pointed out a strategy for recombinant ß-galactosidase-CBD production and immobilization, aiming toward the application in sustainable industrial processes using low-cost inputs.
Assuntos
Reatores Biológicos , Escherichia coli , Celulose , Escherichia coli/genética , Lactose , beta-Galactosidase/genéticaRESUMO
The bacterium Escherichia coli is still considered the first option as a microbial cell factory for recombinant protein production, and affinity chromatography is by far the preferred technique for initial purification after protein expression and cell lysis. In this chapter, we describe the methodology to express and purify recombinant proteins in E. coli tagged with the first two metal-binding proteins proposed as fusion partners. They are the small metal-binding protein SmbP and a mutant of the copper resistance protein CusF3H+. There are several advantages of using them as protein tags: they prevent the formation of inclusion bodies by increasing solubility of the target proteins, they enable purification by immobilized metal-affinity chromatography using Ni(II) ions with high purity, and because of their low molecular weights, excellent final yields are obtained for the target proteins after cleavage and removal of the protein tag. Here we also describe the protocol for the production of proteins in the periplasm of E. coli tagged with two SmbP variants that include the PelB or the TorA signal sequences for transport via the Sec or the Tat pathway, respectively. Based on these methods, we consider CusF3H+ and SmbP excellent alternatives as fusion proteins for the production of recombinant proteins in E. coli.
Assuntos
Cromatografia de Afinidade , Proteínas de Transporte de Cobre , Proteínas de Escherichia coli , Escherichia coli/química , Níquel/química , Periplasma/química , Proteínas de Transporte de Cobre/química , Proteínas de Transporte de Cobre/genética , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Periplasma/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificaçãoRESUMO
Hyalinizing clear cell carcinoma (HCCC), also known as clear cell carcinoma, not otherwise specified [CCC, (NOS)], is a rare minor salivary gland tumor characterized by proliferation of clear cells, organized in trabecular cords, or solid nests within loose to densely hyalinized stroma. It is considered a diagnosis of exclusion by the World Health Organization (WHO) because other salivary tumors may also have a clear cell component. Hence, there is a wide differential diagnosis. EWSR1-ATF1 gene rearrangements are fairly specific for this tumor, however, one of the recent studies have described its presence in clear cell odontogenic carcinoma (CCOC) one of its histologic mimickers. EWSR1 and CREM fusions have recently been described in these tumors but its importance is still not well described. Here we present a case of a 33-year-old woman who presented with a recurrent lesion of the soft palate. Her initial lesion was resected and diagnosed as low-grade myoepithelial tumor. Surgical margins at the time of initial resection were positive and the re-excision was recommended but the patient did not undergo surgery. Two years later, local recurrence at the same site was found and an excision was performed yielding negative margins. Histopathologic examination revealed features consistent with hyalinizing clear cell carcinoma. The patient remains disease free 1 year after the re-excision. The pathology, clinical characteristics, differential diagnosis and treatment of hyalinizing clear cell carcinoma are reviewed.
RESUMO
Hyalinizing clear cell carcinoma (HCCC), also known as clear cell carcinoma, not otherwise specified [CCC, (NOS)], is a rare minor salivary gland tumor characterized by proliferation of clear cells, organized in trabecular cords, or solid nests within loose to densely hyalinized stroma. It is considered a diagnosis of exclusion by the World Health Organization (WHO) because other salivary tumors may also have a clear cell component. Hence, there is a wide differential diagnosis. EWSR1-ATF1 gene rearrangements are fairly specific for this tumor, however, one of the recent studies have described its presence in clear cell odontogenic carcinoma (CCOC) one of its histologic mimickers. EWSR1 and CREM fusions have recently been described in these tumors but its importance is still not well described. Here we present a case of a 33-year-old woman who presented with a recurrent lesion of the soft palate. Her initial lesion was resected and diagnosed as low-grade myoepithelial tumor. Surgical margins at the time of initial resection were positive and the re-excision was recommended but the patient did not undergo surgery. Two years later, local recurrence at the same site was found and an excision was performed yielding negative margins. Histopathologic examination revealed features consistent with hyalinizing clear cell carcinoma. The patient remains disease free 1 year after the re-excision. The pathology, clinical characteristics, differential diagnosis and treatment of hyalinizing clear cell carcinoma are reviewed.
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Humanos , Feminino , Adulto , Neoplasias das Glândulas Salivares/diagnóstico , Carcinoma , Patologia Clínica , Diagnóstico DiferencialRESUMO
The infectious salmon anemia virus (ISAV), etiological agent of the disease by the same name, causes major losses to the salmon industry. Classified as a member of the Orthomyxoviridae family, ISAV is characterized by the presence of two surface glycoproteins termed hemagglutinin esterase (HE) and fusion protein (F), both of them directly involved in the initial interaction of the virus with the target cell. HE mediates receptor binding and destruction, while F promotes the fusion process of the viral and cell membranes. The carboxy-terminal end of F (F2) possesses canonical structural characteristics of a type I fusion protein, while no functional properties have been proposed for the amino-terminal (F1) region. In this report, based on in silico modeling, we propose a tertiary structure for the F1 region, which resembles a sialic acid binding domain. Furthermore, using recombinant forms of both HE and F proteins and an in vitro model system, we demonstrate the interaction of F with a cell receptor, the hydrolysis of this receptor by the HE esterase, and a crucial role for F1 in the fusion mechanism. Our interpretation is that binding of F to its cell receptor is fundamental for membrane fusion and that the esterase in HE modulates this interaction.
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Abstract Acne Vulgaris is a common skin disease caused by Propionibacterium acnes, an anaerobic microbiota of human skin that plays a vital role in the pathology of acne. The aim of this study was to prepare nanoparticles containing an acne recombinant protein and determine its ability as an oral acne vaccine in mice. The recombinant Sialidase-CAMP gene was expressed and purified in a prokaryotic host. The chitosan nanoparticles containing the recombinant protein were prepared, encapsulated, and administered by both oral and subcutaneous routes to Balb/c mice. Sera IgA and IgG and stool IgA titers were measured by ELISA, and the immunized mice were challenged against P. acnes. A 65 kDa recombinant protein was confirmed by SDS-PAGE and western blot. The size and zeta potential of nanoparticles were 80 nm and +18 mV, respectively. After oral immunization, the serum IgG and IgA titers were 1:3200 and 1:16, respectively, and the stool IgA titer was 1:8. In the subcutaneous route, the serum IgG titer was 1:51200. Immunized mice showed no inflammation in the ear of challenged mice. It is the first study that examines a chitosan-nanoparticulated acne fusion protein as an applicable acne vaccine candidate with appropriate immunogenicity potential. Further studies are required to validate the clinical usefulness of this vaccine candidate.
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Animais , Feminino , Camundongos , Propionibacterium acnes/efeitos dos fármacos , Acne Vulgar/prevenção & controle , Quitosana/administração & dosagem , Nanopartículas/administração & dosagem , Proteínas Recombinantes , Ensaio de Imunoadsorção Enzimática , Western Blotting , Imunização/métodos , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Camundongos Endogâmicos BALB C , NeuraminidaseRESUMO
Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, and is endemic in many Latin American countries. Diagnosis is based on serologic testing and the WHO recommends two or more serological tests for confirmation. Acidic ribosomal P protein of T. cruzi showed strong reactivity against positive sera of patients, and we cloned the protein after fragmenting it to enhance its antigenicity and solubility. Twelve positive sera of Chagas disease patients were reacted with the fragmented ribosomal P protein using western blot. Detection rate and density for each fragment were determined. Fragments F1R1, F1R2, and F2R1 showed 100% rate of detection, and average density scoring of 2.00, 1.67, and 2.42 from a maximum of 3.0, respectively. Therefore, the F2R1 fragment of the ribosomal P protein of T. cruzi could be a promising antigen to use in the diagnosis of Chagas disease in endemic regions with high specificity and sensitivity.
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Anticorpos Antiprotozoários/sangue , Doença de Chagas/diagnóstico , Proteínas Ribossômicas/imunologia , Trypanosoma cruzi/imunologia , Western Blotting , Brasil , Doença de Chagas/sangue , Doença de Chagas/imunologia , Doenças Endêmicas , Humanos , Proteínas Recombinantes/imunologiaRESUMO
BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is a rare and aggressive malignant neoplasm typically located in the abdomen or pelvis. Other possible locations are the chest, pleura, scrotum, and central nervous system. DSRCT originally arising from the brachial plexus (BP) is extremely rare, to the best of our knowledge, only two cases have been previously described in the English scientific literature. CASE DESCRIPTION: The authors present one new case of DSRCT arising from the left BP, the first in this location with rapid progression and in a female patient. We also highlight the importance of multimodal therapy, which included resection and both adjuvant radiation and chemotherapy. Macroscopic and microscopic characteristics of the lesion are detailed, as well as the patient's status at 56-month follow-up. CONCLUSION: For primary BP DSRCT, aggressive subtotal resection followed by radiation and chemotherapy can be satisfactory for disease control and for maintaining or improving the neurological status.
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Canine distemper is a highly contagious systemic viral disease, with worldwide distribution that affects a wide variety of terrestrial carnivores. This study characterized full-length fusion (F) genes from 15 Brazilian wild-type canine distemper virus (CDV) strains collected between 2003-2004 (n = 6) and 2013-2016 (n = 9). Using deduced amino acid (aa) sequence analysis, 14 strains were classified into Europe 1/South America 1 (EU1/SA1) lineage, with a temporal clustering into past (2003-2004) and contemporary (2013-2016) strains. One strain clustered to Rockborn-like lineage, showing high similarity (98.5%) with the Rockborn vaccine strain. In analyzed strains, the fusion protein signal-peptide (Fsp) coding region was highly variable at the aa level (67.4%-96.2%). The Brazilian strains were more Fsp-divergent from the North America 1 (NA1) strains (24.5%-36.3%) than from the Rockborn (11.2%-14.9%) vaccine strain. Seventeen cysteine residues in the full-length F gene and four non-conserved glycosylation sites in the Fsp region were detected. The results reveal that past and contemporary CDV strains are currently co-circulating. This first analysis of full-length F genes from Brazilian wild-type CDV strains contributes to knowledge of molecular epidemiology of CDV viral infection and evolution.
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Vírus da Cinomose Canina/genética , Cinomose/epidemiologia , Variação Genética , Proteínas Virais de Fusão/genética , Animais , Brasil/epidemiologia , Cães , Feminino , Masculino , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Vacinas ViraisRESUMO
Hypertension is a worldwide health problem. It is the main cardiovascular risk factor and affects about 31% of the world's adult population. The drugs used to control hypertension may cause side effects; for this reason, there are many investigations focused on searching for alternatives to control or prevent this disease through diet. For example, many peptides have demonstrated antihypertensive effects. The insertion of bioactive peptides is a biotechnological implement used to improve the nutraceutical properties of proteins. This work reviews the current data on the insertion of antihypertensive peptides (AHPs) into food proteins, the systems used to produce the AHPs, the advantages and disadvantages between them, the parameters to produce them at major scales, and their potential applications in pharmacy and functional foods.