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1.
Int J Mol Sci ; 25(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063100

RESUMO

The Semliki Forest virus capsid protein (C) is an RNA binding protein which exhibits both specific and unspecific affinities to single-strand nucleic acids. The putative use of the self-amplifying RNAs (saRNAs) of alphaviruses for biotechnological purpose is one of the main studied strategies concerning RNA-based therapies or immunization. In this work, a recombinant C protein from SFV was expressed and purified from bacteria and used to associate in vitro with a saRNA derived from SFV. Results showed that the purified form of C protein can associate with the saRNA even after high temperature treatment. The C protein was associated with a modified saRNA coding for the green fluorescent protein (GFP) and delivered to murine macrophage cells which expressed the GFP, showing that the saRNA was functional after being associated with the recombinant purified C protein.


Assuntos
Proteínas do Capsídeo , Macrófagos , RNA Viral , Proteínas Recombinantes , Vírus da Floresta de Semliki , Vírus da Floresta de Semliki/genética , Animais , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Camundongos , Macrófagos/metabolismo , Macrófagos/virologia , Proteínas Recombinantes/genética , RNA Viral/genética , Linhagem Celular , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo
2.
Int J Mol Sci ; 24(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37762254

RESUMO

The Zika Virus (ZIKV) is an emerging arbovirus of great public health concern, particularly in the Americas after its last outbreak in 2015. There are still major challenges regarding disease control, and there is no ZIKV vaccine currently approved for human use. Among many different vaccine platforms currently under study, the recombinant envelope protein from Zika Virus (rEZIKV) constitutes an alternative option for vaccine development and has great potential for monitoring ZIKV infection and antibody response. This study describes a method to obtain a bioactive and functional rEZIKV using an E. coli expression system, with the aid of a 5-L airlift bioreactor and following an automated fast protein liquid chromatography (FPLC) protocol, capable of obtaining high yields of approximately 20 mg of recombinant protein per liter of bacterium cultures. The purified rEZIKV presented preserved antigenicity and immunogenicity. Our results show that the use of an airlift bioreactor for the production of rEZIKV is ideal for establishing protocols and further research on ZIKV vaccines bioprocess, representing a promising system for the production of a ZIKV envelope recombinant protein-based vaccine candidate.


Assuntos
Vacinas Virais , Infecção por Zika virus , Zika virus , Humanos , Zika virus/genética , Proteínas do Envelope Viral/genética , Anticorpos Neutralizantes , Escherichia coli , Anticorpos Antivirais , Vacinas Virais/genética , Vacinas de Subunidades Antigênicas/genética , Proteínas Recombinantes/genética , Reatores Biológicos
3.
Mol Ther ; 28(5): 1276-1286, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32220305

RESUMO

Malignant brain tumors are among the most aggressive cancers with poor prognosis and no effective treatment. Recently, we reported the oncolytic potential of Zika virus infecting and destroying the human central nervous system (CNS) tumors in vitro and in immunodeficient mice model. However, translating this approach to humans requires pre-clinical trials in another immunocompetent animal model. Here, we analyzed the safety of Brazilian Zika virus (ZIKVBR) intrathecal injections in three dogs bearing spontaneous CNS tumors aiming an anti-tumoral therapy. We further assessed some aspects of the innate immune and inflammatory response that triggers the anti-tumoral response observed during the ZIKVBR administration in vivo and in vitro. For the first time, we showed that there were no negative clinical side effects following ZIKVBR CNS injections in dogs, confirming the safety of the procedure. Furthermore, the intrathecal ZIKVBR injections reduced tumor size in immunocompetent dogs bearing spontaneous intracranial tumors, improved their neurological clinical symptoms significantly, and extended their survival by inducing the destruction specifically of tumor cells, sparing normal neurons, and activating an immune response. These results open new perspectives for upcoming virotherapy using ZIKV to destroy and induce an anti-tumoral immune response in CNS tumors for which there are currently no effective treatments.


Assuntos
Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/terapia , Terapia Viral Oncolítica/métodos , Segurança do Paciente , Carga Tumoral , Infecção por Zika virus/complicações , Zika virus/imunologia , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Citocinas/metabolismo , Modelos Animais de Doenças , Cães , Imunidade , Injeções Espinhais , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/virologia , Monócitos/imunologia , Monócitos/virologia , Neurônios/metabolismo , Neurônios/virologia , Resultado do Tratamento
4.
Appl Microbiol Biotechnol ; 102(11): 4773-4783, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29675803

RESUMO

The transmembrane rabies virus glycoprotein (RVGP) is the main antigen of vaccine formulations used around the world to prevent rabies, the most lethal preventable infectious disease known. The objective of this work was to evaluate the potential of a bioreactor using wave-induced agitation in the initial steps of scaling up the rRVGP production process by a Drosophila melanogaster S2 cell line to produce rRVGP in sufficient quantities for immunization and characterization studies. Taking advantage of some remarkable features recognized in Drosophila S2 cells for scaling the culture process, a robust recombinant lineage (S2MtRVGPH-His) engineered by our group for the expression of rRVGP using a copper-inducible promoter was used in the bioreactor cultures. The WAVE Bioreactor was chosen because it represents an innovative approach to the cultivation of animal cells using single-use technology. For that purpose, we firstly established a procedure for culturing the S2MtRVGPH-His lineage in 100 mL Schott flasks. Using an inoculum of 5 × 105 cells/mL in culture medium (Sf900-III) induced with solution of CuSO4 (0.7 mM) and a convenient pH range (6.2-7.0), optimal parameter values such as time of induction (72 h) and temperature (28 °C) to increase rRVGP production could be defined. This procedure was reproduced in culture experiments conducted in a WAVE Bioreactor™ 2/10 using a 2 L Cellbag. The results in Schott flasks and in WAVE Bioreactor™ were very similar, yielding a maximum titer of rRVGP above of 1 mg.L-1. The immunization study showed that the rRVGP produced in the bioreactor was of high immunogenic quality.


Assuntos
Reatores Biológicos , Glicoproteínas/biossíntese , Microbiologia Industrial/métodos , Proteínas Recombinantes/biossíntese , Proteínas Virais/biossíntese , Animais , Técnicas de Cultura de Células , Linhagem Celular , Drosophila melanogaster/citologia , Vírus da Raiva
5.
Arch Virol ; 162(2): 323-332, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27796547

RESUMO

The rabies virus envelope glycoprotein (RVGP) is the main antigen of rabies virus and is the only viral component present in all new rabies vaccines being proposed. Many approaches have been taken since DNA recombinant technology became available to express an immunogenic recombinant rabies virus glycoprotein (rRVGP). These attempts are reviewed here, and the relevant results are discussed with respect to the general characteristics of the rRVGP, the expression system used, the expression levels achieved, the similarity of the rRVGP to the native glycoprotein, and the immunogenicity of the vaccine preparation. The most recent studies of rabies vaccine development have concentrated on in vivo expression of rRVGP by viral vector transduction, serving as the biotechnological basis for a new generation of rabies vaccines.


Assuntos
Anticorpos Antivirais/biossíntese , Antígenos Virais/imunologia , Imunogenicidade da Vacina , Vacina Antirrábica/genética , Vírus da Raiva/imunologia , Proteínas do Envelope Viral/genética , Animais , Antígenos Virais/química , Antígenos Virais/genética , Linhagem Celular , Drosophila melanogaster/citologia , Drosophila melanogaster/virologia , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/biossíntese , Vírus da Raiva/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Spodoptera/citologia , Spodoptera/virologia , Vacinas Sintéticas , Proteínas do Envelope Viral/biossíntese , Proteínas do Envelope Viral/imunologia
6.
Mol Biotechnol ; 66(2): 354-364, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37162721

RESUMO

This work aimed to assess the Sf9 cell metabolism during growth, and infection steps with recombinant baculovirus bearing rabies virus proteins, to finally obtain rabies VLP in two culture systems: Schott flask (SF) and stirred tank reactor (STR). Eight assays were performed in SF and STR (four assays in each system) using serum-free SF900 III culture medium. Two non-infection growth kinetics assays and six recombinant baculovirus infection assays. The infection runs were carried out at 0.1 pfu/cell multiplicity of infection (MOI) for single baculovirus bearing rabies glycoprotein (BVG) and matrix protein (BVM) and a coinfection with both baculoviruses at MOI of 3 and 2 pfu/cell for BVG and BVM, respectively. The SF assays were done in triplicate. The glucose, glutamine, glutamate, lactate, and ammonium uptake or release specific rates were quantified over the exponential growth phase and infection stage. The highest uptake specific rate was observed for glucose (42.5 × 10-12 mmol cell/h) in SF and for glutamine (30.8 × 10-12 mmol/cell/h) in STR, in the exponential growth phases. A wave pattern was observed for assessed analytes throughout the infection phase and the glucose had the highest wave amplitude within the 10-10 mmol cell/h order. This alternative uptake and release behavior is in harmony with the lytic cycle of baculovirus in insect cells. The virus propagation and VLP generation were not limited by glucose, glutamine, and glutamate, neither by the toxicity of lactate nor ammonium under the conditions appraised in this work. The findings from this work can be useful to set baculovirus infection processes at high cell density to improve rabies VLP yield, purity, and productivity.


Assuntos
Compostos de Amônio , Vírus da Raiva , Raiva , Animais , Células Sf9 , Vírus da Raiva/genética , Glutamina , Baculoviridae/genética , Proteínas Recombinantes/genética , Meios de Cultura Livres de Soro , Ácido Glutâmico , Lactatos , Glucose , Spodoptera
7.
Mol Biotechnol ; 65(6): 970-982, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36396754

RESUMO

This work aimed to describe the dynamics of the Sf9 insect cells death and primary metabolism when this host is infected simultaneously by two recombinant baculoviruses (BV) expressing rabies glycoprotein (BVG) and matrix protein (BVM) genes to produce rabies virus-like particles (VLP) at different multiplicities of infection (MOI). Schott flasks essays covering a wide range of MOI for both BV were performed. Viable cell density, cell viability, glucose, glutamine, glutamate, lactate, ammonium, and rabies proteins concentrations were monitored over the infection phase. The expression of both recombinant proteins was not limited by glucose, glutamine, and glutamate in a broad MOI (pfu/cell) range of BVG (0.15-12.5) and BVM (0.1-5.0) using SF900 III serum free culture medium. Death phase initiation and the specific death rate depend on BV MOI. The wave pattern of nutrient/metabolite profiles throughout the viral infection phase is related to the baculovirus lytic cycle. The optimal MOIs ratio between BVG (2.5-4.5) and BVM (1.0-3.0) for maximum protein expression was defined. The produced rabies VLP sizes are close to 78 nm. In general, these work outputs bring a better understanding of the metabolic performance of Sf9 cells when infected by BV for producing VLP, and specifically, for progressing in a rabies VLP vaccine development.


Assuntos
Vacina Antirrábica , Vírus da Raiva , Raiva , Animais , Humanos , Baculoviridae/genética , Baculoviridae/metabolismo , Células Sf9 , Linhagem Celular , Vírus da Raiva/genética , Glutamina/metabolismo , Glutamatos/metabolismo , Glucose/metabolismo
8.
Front Pharmacol ; 14: 1181566, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377933

RESUMO

Introdutcion: The Zika virus (ZIKV) infections are a healthcare concern mostly in the Americas, Africa, and Asia but have increased its endemicity area beyond these geographical regions. Due to the advances in infections by Zika virus, it is imperative to develop diagnostic and preventive tools against this viral agent. Virus-like particles (VLPs) appear as a suitable approach for use as antiviral vaccines. Methods: In this work, a methodology was established to produce virus-like particles containing the structural proteins, C, prM, and E of Zika virus produced in insect cells using the gene expression system derived from baculovirus. The vector pFast- CprME -ZIKV was constructed containing the gene sequences of Zika virus structural proteins and it was used to generate the recombinant bacmids (Bac- CprME -ZIKV) through transformation into DH10BacTM cells. The Bac- CprME -ZIKV was transfected in Spodoptera frugiperda (Sf9) insect cells and batches of BV- CprME -ZIKV were obtained by infection assays using a multiplicity of infection of 2. The Sf9 cells were infected, and the supernatant was collected 96 h post-infection. The expression of the CprME -ZIKV protein on the cell surface could be observed by immunochemical assays. To concentrate and purify virus-like particles, the sucrose and iodixanol gradients were evaluated, and the correct CprME -ZIKV proteins' conformation was evaluated by the Western blot assay. The virus-like particles were also analyzed and characterized by transmission electron microscopy. Results and discussion: Spherical structures like the native Zika virus from 50 to 65 nm containing the CprME -ZIKV proteins on their surface were observed in micrographs. The results obtained can be useful in the development path for a vaccine candidate against Zika virus.

9.
J Biotechnol ; 363: 19-31, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36587847

RESUMO

This work aimed to quantify growth and biochemical parameters (viable cell density, Xv; cell viability, CV; glucose, lactate, glutamine, glutamate, ammonium, and potassium concentrations) in upstream stages to obtain rabies virus-like particles (rabies VLP) from insect cell-baculovirus system using on-line and off-line Raman spectra to calibrate global models with minimal experimental data. Five cultivations in bioreactor were performed. The first one comprised the growth of uninfected Spodoptera frugiperda (Sf9) cells, the second and third runs to obtain recombinant baculovirus (rBV) bearing Rabies G glycoprotein and matrix protein, respectively. The fourth one involved the generation of rabies VLP from rBVs and the last one was a repetition of the third one with cell inoculum infected by rBV. The spectra were acquired through a Raman spectrometer with a 785-nm laser source. The fitted Partial Least Square models for nutrients and metabolites were comparable with those previously reported for mammalian cell lines (Relative error < 15 %). However, the use of this chemometrics approach for Xv and CV was not as accurate as it was for other parameters. The findings from this work established the basis for bioprocess Raman spectroscopical monitoring using insect cells for VLP manufacturing, which are gaining ground in the pharmaceutical industry.


Assuntos
Vírus da Raiva , Raiva , Animais , Vírus da Raiva/genética , Análise Espectral Raman , Linhagem Celular , Reatores Biológicos , Baculoviridae , Proteínas Recombinantes , Insetos , Spodoptera , Mamíferos
10.
Viruses ; 15(2)2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36851769

RESUMO

Neutralizing antibodies (nAbs) are a critical part of coronavirus disease 2019 (COVID-19) research as they are used to gain insight into the immune response to severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infections. Among the technologies available for generating nAbs, DNA-based immunization methods are an alternative to conventional protocols. In this pilot study, we investigated whether DNA-based immunization by needle injection in rabbits was a viable approach to produce a functional antibody response. We demonstrated that three doses of DNA plasmid carrying the gene encoding the full-length spike protein (S) or the receptor binding domain (RBD) of SARS-CoV-2 induced a time-dependent increase in IgG antibody avidity maturation. Moreover, the IgG antibodies displayed high cross neutralization by live SARS-CoV-2 and pseudoviruses neutralization assays. Thus, we established a simple, low cost and feasible DNA-based immunization protocol in rabbits that elicited high IgG avidity maturation and nAbs production against SARS-CoV-2, highlighting the importance of DNA-based platforms for developing new immunization strategies against SARS-CoV-2 and future emerging epidemics.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Coelhos , SARS-CoV-2/genética , Anticorpos Neutralizantes , Projetos Piloto , COVID-19/prevenção & controle , Imunoglobulina G , Imunização
11.
Cells ; 11(9)2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35563763

RESUMO

Zebrafish are increasingly being utilized as a model to investigate infectious diseases and to advance the understanding of pathogen-host interactions. Here, we take advantage of the zebrafish to recapitulate congenital ZIKV infection and, for the first time, demonstrate that it can be used to model infection and reinfection and monitor anti-viral and inflammatory immune responses, as well as brain growth and eye abnormalities during embryonic development. By injecting a Brazilian strain of ZIKV into the yolk sac of one-cell stage embryos, we confirmed that, after 72 h, ZIKV successfully infected larvae, and the physical condition of the virus-infected hosts included gross morphological changes in surviving embryos (84%), with a reduction in larval head size and retinal damage characterized by increased thickness of the lens and inner nuclear layer. Changes in locomotor activity and the inability to perceive visual stimuli are a result of changes in retinal morphology caused by ZIKV. Furthermore, we demonstrated the ability of ZIKV to replicate in zebrafish larvae and infect new healthy larvae, impairing their visual and neurological functions. These data reinforce the deleterious activity of ZIKV in the brain and visual structures and establish the zebrafish as a model to study the molecular mechanisms involved in the pathology of the virus.


Assuntos
Traumatismos Oculares , Doenças Retinianas , Infecção por Zika virus , Zika virus , Animais , Larva , Peixe-Zebra , Zika virus/fisiologia
12.
Sci Rep ; 12(1): 15733, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131132

RESUMO

Recent outbreaks of Zika virus (ZIKV) infection have highlighted the need for a better understanding of ZIKV-specific immune responses. The ZIKV envelope glycoprotein (EZIKV) is the most abundant protein on the virus surface and it is the main target of the protective immune response. EZIKV protein contains the central domain (EDI), a dimerization domain containing the fusion peptide (EDII), and a domain that binds to the cell surface receptor (EDIII). In this study, we performed a systematic comparison of the specific immune response induced by different EZIKV recombinant proteins (EZIKV, EDI/IIZIKV or EDIIIZIKV) in two mice strains. Immunization induced high titers of E-specific antibodies which recognized ZIKV-infected cells and neutralized the virus. Furthermore, immunization with EZIKV, EDI/IIZIKV and EDIIIZIKV proteins induced specific IFNγ-producing cells and polyfunctional CD4+ and CD8+ T cells. Finally, we identified 4 peptides present in the envelope protein (E1-20, E51-70, E351-370 and E361-380), capable of inducing a cellular immune response to the H-2Kd and H-2Kb haplotypes. In summary, our work provides a detailed assessment of the immune responses induced after immunization with different regions of the ZIKV envelope protein.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Linfócitos T CD8-Positivos/metabolismo , Imunidade Celular , Imunidade Humoral , Camundongos , Proteínas Recombinantes , Proteínas do Envelope Viral
13.
Vaccines (Basel) ; 11(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36679884

RESUMO

This work aimed to assess, following upstream optimization in Schott flasks, the scalability from this culture platform to a stirred-tank bioreactor in order to yield rabies-recombinant baculovirus, bearing genes of G (BVG) and M (BVM) proteins, and to obtain rabies virus-like particles (VLP) from them, using Sf9 insect cells as a host. Equivalent assays in Schott flasks and a bioreactor were performed to compare both systems and a multivariate statistical approach was also carried out to maximize VLP production as a function of BVG and BVM's multiplicity of infection (MOI) and harvest time (HT). Viable cell density, cell viability, virus titer, BVG and BVM quantification by dot-blot, and BVG quantification by Enzyme-Linked Immunosorbent Assay (ELISA) were monitored throughout the assays. Furthermore, transmission electron microscopy was used to characterize rabies VLP. The optimal combination for maximum VLP expression was BVG and BVM MOI of 2.3 pfu/cell and 5.1 pfu/cell, respectively, and 108 h of harvest time. The current study confirmed that the utilization of Schott flasks and a benchtop bioreactor under the conditions applied herein are equivalent regarding the cell death kinetics corresponding to the recombinant baculovirus infection process in Sf9 cells. According to the results, the hydrodynamic and chemical differences in both systems seem to greatly affect the virus and VLP integrity after release.

14.
Sci Rep ; 12(1): 3890, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273234

RESUMO

The new outbreak of coronavirus disease 2019 (COVID-19) has infected and caused the death of millions of people worldwide. Intensive efforts are underway around the world to establish effective treatments. Immunoglobulin from immunized animals or plasma from convalescent patients might constitute a specific treatment to guarantee the neutralization of the virus in the early stages of infection, especially in patients with risk factors and a high probability of progressing to severe disease. Worldwide, a few clinical trials using anti-SARS-CoV-2 immunoglobulins from horses immunized with the entire spike protein or fragments of it in the treatment of patients with COVID-19 are underway. Here, we describe the development of an anti-SARS-CoV-2 equine F(ab')2 immunoglobulin using a newly developed SARS-CoV-2 viral antigen that was purified and inactivated by radiation. Cell-based and preclinical assays showed that the F(ab')2 immunoglobulin successfully neutralizes the virus, is safe in animal models, and reduces the severity of the disease in a hamster model of SARS-CoV-2 infection and disease.


Assuntos
COVID-19/terapia , Imunoglobulinas/uso terapêutico , Receptores Imunológicos/uso terapêutico , SARS-CoV-2/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Cavalos/imunologia , Humanos , Imunoglobulinas/imunologia , Imunoglobulinas/isolamento & purificação , Masculino , Mesocricetus/imunologia , Plasmaferese/veterinária , Receptores Imunológicos/imunologia
15.
Toxins (Basel) ; 13(11)2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34822563

RESUMO

Caecilians (order Gymnophiona) are apodan, snake-like amphibians, usually with fossorial habits, constituting one of the most unknown groups of terrestrial vertebrates. As in orders Anura (frogs, tree frogs and toads) and Caudata (salamanders and newts), the caecilian skin is rich in mucous glands, responsible for body lubrication, and poison glands, producing varied toxins used in defence against predators and microorganisms. Whereas in anurans and caudatans skin gland morphology has been well studied, caecilian poison glands remain poorly elucidated. Here we characterised the skin gland morphology of the caecilian Siphonops annulatus, emphasising the poison glands in comparison to those of anurans and salamanders. We showed that S. annulatus glands are similar to those of salamanders, consisting of several syncytial compartments full of granules composed of protein material but showing some differentiated apical compartments containing mucus. An unusual structure resembling a mucous gland is frequently observed in lateral/apical position, apparently connected to the main duct. We conclude that the morphology of skin poison glands in caecilians is more similar to salamander glands when compared to anuran glands that show a much-simplified structure.


Assuntos
Anfíbios/anatomia & histologia , Glândulas Exócrinas/anatomia & histologia , Animais , Feminino , Masculino , Muco/metabolismo , Venenos/metabolismo
16.
Mol Biotechnol ; 63(11): 1068-1080, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34228257

RESUMO

Rabies is an ancient zoonotic disease that still causes the death of over 59,000 people worldwide each year. The rabies lyssavirus encodes five proteins, including the envelope glycoprotein and the matrix protein. RVGP is the only protein exposed on the surface of viral particle, and it can induce immune response with neutralizing antibody formation. RVM has the ability to assist with production process of virus-like particles. VLPs were produced in recombinant baculovirus system. In this work, two recombinant baculoviruses carrying the RVGP and RVM genes were constructed. From the infection and coinfection assays, we standardized the best multiplicity of infection and the best harvest time. Cell supernatants were collected, concentrated, and purified by sucrose gradient. Each step was used for protein detection through immunoassays. Sucrose gradient analysis enabled to verify the separation of VLPs from rBV. Through the negative contrast technique, we visualized structures resembling rabies VLPs produced in insect cells and rBV in the different fractions of the sucrose gradient. Using ELISA to measure total RVGP, the recovery efficiency of VLPs at each stage of the purification process was verified. Thus, these results encourage further studies to confirm whether rabies VLPs are a promising candidate for a veterinary rabies vaccine.


Assuntos
Baculoviridae/genética , Insetos/metabolismo , Vacina Antirrábica/biossíntese , Vírus da Raiva/metabolismo , Raiva/virologia , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Animais , Baculoviridae/isolamento & purificação , Baculoviridae/metabolismo , Células Cultivadas , Humanos , Insetos/imunologia , Insetos/virologia , Vacina Antirrábica/genética , Vacina Antirrábica/imunologia , Vacina Antirrábica/isolamento & purificação , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação
17.
Life (Basel) ; 11(6)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063766

RESUMO

Biopharmaceutical production is currently a multibillion-dollar industry with high growth perspectives. The research and development of biologically sourced pharmaceuticals are extremely important and a reality in our current healthcare system. Interferon alpha consensus (cIFN) is a non-natural synthetic antiviral molecule that comprises all the most prevalent amino acids of IFN-α into one consensus protein sequence. For clinical use, cIFN is produced in E. coli in the form of inclusion bodies. Here, we describe the use of two solubility tags (Fh8 and DsbC) to improve soluble cIFN production. Furthermore, we analyzed cIFN production in different culture media and temperatures in order to improve biopharmaceutical production. Our results demonstrate that Fh8-cIFN yield was improved when bacteria were cultivated in autoinduction culture medium at 30 °C. After hydrolysis, the recovery of soluble untagged cIFN was 58% from purified Fh8-cIFN molecule, fourfold higher when compared to cIFN recovered from the DsbC-cIFN, which achieved 14% recovery. The biological activity of cIFN was tested on in vitro model of antiviral effect against Zika, Mayaro, Chikungunya and SARS-CoV-2 virus infection in susceptible VERO cells. We show, for the first time, that cIFN has a potent activity against these viruses, being very low amounts of the molecule sufficient to inhibit virus multiplication. Thus, this molecule could be used in a clinical approach to treat Arboviruses and SARS-CoV-2.

18.
Vaccine ; 38(20): 3653-3664, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32247567

RESUMO

The recent outbreaks of Zika virus (ZIKV) infection and the potential association with Guillain-Barré syndrome in adults and with congenital abnormalities have highlighted the urgency for an effective vaccine. The ZIKV Envelope glycoprotein (EZIKV) is the most abundant protein on the virus surface, and has been evaluated together with the pre-membrane protein (prM) of the viral coat as a vaccine candidate in clinical trials. In this study, we performed a head-to-head comparison of the immune response induced by different EZIKV-based vaccine candidates in mice. We compared different platforms (DNA, recombinant protein), adjuvants (poly (I:C), CpG ODN 1826) and immunization strategies (homologous, heterologous). The hierarchy of adjuvant potency showed that poly (I:C) was a superior adjuvant than CpG ODN. While poly (I:C) assisted immunization reached a plateau in antibody titers after two doses, the CpG ODN group required an extra immunization dose. Besides, the administration of poly (I:C) induced higher EZIKV-specific cellular immune responses than CpG ODN. We also show that immunization with homologous prime-boost EZIKV protein + poly (I:C) regimen induced a more robust humoral response than homologous DNA (pVAX-EZIKV) or heterologous regimens (DNA/protein or protein/DNA). A detailed analysis of cellular immune responses revealed that homologous (EZIKV + poly (I:C)) and heterologous (pVAX-EZIKV/EZIKV + poly (I:C)) prime-boost regimens induced the highest magnitude of IFN-γ secreting cells and cytokine-producing CD4+ T cells. Overall, our data demonstrate that homologous EZIKV + poly (I:C) prime-boost immunization is sufficient to induce more robust specific-EZIKV humoral and cellular immune responses than the other strategies that contemplate homologous DNA (pVAX-EZIKV) or heterologous (pVAX-EZIKV/EZIKV + poly (I:C), and vice-versa) immunizations.


Assuntos
Vacinas de DNA , Proteínas do Envelope Viral , Infecção por Zika virus , Zika virus , Animais , Imunidade Celular , Imunização Secundária , Camundongos , Camundongos Endogâmicos BALB C , Envelope Viral , Zika virus/imunologia , Infecção por Zika virus/prevenção & controle
19.
Biotechnol Prog ; 36(6): e3046, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32628317

RESUMO

Most rabies vaccines are based on inactivated virus, which production process demands a high level of biosafety structures. In the past decades, recombinant rabies virus glycoprotein (RVGP) produced in several expression systems has been extensively studied to be used as an alternative vaccine. The immunogenic characteristics of this protein depend on its correct conformation, which is present only after the correct post-translational modifications, typically performed by animal cells. The main challenge of using this protein as a vaccine candidate is to keep its trimeric conformation after the purification process. We describe here a new immunoaffinity chromatography method using a monoclonal antibody for RVGP Site II for purification of recombinant rabies virus glycoprotein expressed on the membrane of Drosophila melanogaster S2 cells. RVGP recovery achieved at least 93%, and characterization analysis showed that the main antigenic proprieties were preserved after purification.


Assuntos
Técnicas de Cultura de Células/métodos , Glicoproteínas/isolamento & purificação , Vírus da Raiva/isolamento & purificação , Proteínas Virais/isolamento & purificação , Animais , Linhagem Celular , Drosophila melanogaster/citologia , Glicoproteínas/biossíntese , Glicoproteínas/genética , Humanos , Vírus da Raiva/química , Vírus da Raiva/patogenicidade , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Virais/biossíntese , Proteínas Virais/genética
20.
PLoS Negl Trop Dis ; 14(8): e0008424, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745093

RESUMO

Zika virus (ZIKV) causes congenital Zika syndrome (CZS), which is characterized by fetal demise, microcephaly and other abnormalities. ZIKV in the pregnant woman circulation must cross the placental barrier that includes fetal endothelial cells and trophoblasts, in order to reach the fetus. CZS occurs in ~1-40% of cases of pregnant women infected by ZIKV, suggesting that mothers' infection by ZIKV during pregnancy is not deterministic for CZS phenotype in the fetus. Therefore, other susceptibility factors might be involved, including the host genetic background. We have previously shown that in three pairs of dizygotic twins discordant for CZS, neural progenitor cells (NPCs) from the CZS-affected twins presented differential in vitro ZIKV susceptibility compared with NPCs from the non-affected. Here, we analyzed human-induced-pluripotent-stem-cell-derived (hiPSC-derived) trophoblasts from these twins and compared by RNA-Seq the trophoblasts from CZS-affected and non-affected twins. Following in vitro exposure to a Brazilian ZIKV strain (ZIKVBR), trophoblasts from CZS-affected twins were significantly more susceptible to ZIKVBR infection when compared with trophoblasts from the non-affected. Transcriptome profiling revealed no differences in gene expression levels of ZIKV candidate attachment factors, IFN receptors and IFN in the trophoblasts, either before or after ZIKVBR infection. Most importantly, ZIKVBR infection caused, only in the trophoblasts from CZS-affected twins, the downregulation of genes related to extracellular matrix organization and to leukocyte activation, which are important for trophoblast adhesion and immune response activation. In addition, only trophoblasts from non-affected twins secreted significantly increased amounts of chemokines RANTES/CCL5 and IP10 after infection with ZIKVBR. Overall, our results showed that trophoblasts from non-affected twins have the ability to more efficiently activate genes that are known to play important roles in cell adhesion and in triggering the immune response to ZIKV infection in the placenta, and this may contribute to predict protection from ZIKV dissemination into fetuses' tissues.


Assuntos
Expressão Gênica , Trofoblastos/metabolismo , Gêmeos Dizigóticos , Infecção por Zika virus/congênito , Quimiocinas/metabolismo , Matriz Extracelular , Feminino , Predisposição Genética para Doença , Humanos , Células-Tronco Pluripotentes Induzidas , Lactente , Gravidez , Complicações Infecciosas na Gravidez/genética , Complicações Infecciosas na Gravidez/virologia , Trofoblastos/virologia , Zika virus , Infecção por Zika virus/genética
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