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1.
Bioconjug Chem ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39332819

RESUMEN

Ferritin (Ft) nanoparticles have become versatile platforms for displaying antigens, being a promising technology for vaccine development. While genetic fusion has traditionally been the preferred method for antigen display, concerns about improper folding and steric hindrance that may compromise vaccine efficacy or stability have prompted alternative approaches. Bioconjugation offers the advantage of preserving native protein structure and function, with recent advancements improving efficiency and specificity. In this study, we used tyrosinase (TYR) to bioconjugate the receptor binding domain of the SARS-CoV-2 spike protein, tagged with a tyrosine (RBD-Y), to native cysteines on Ft, resulting in RBD-Y-Ft nanoparticles. We quantified available cysteines on ferritin using Ellman's assay and monitored their reduction during the reactions. Denaturing analytics (via SDS-PAGE, Western blot, and LC-TOF-MS) confirmed the formation of RBD-Y-Ft monomers with an expected molecular weight of 46 kDa. Mass photometry and HPLC estimated a molecular weight of RBD-Y-Ft nanoparticles of 680 kDa, which was higher than that of nonfunctionalized ferritin (480 kDa), indicating successful binding of up to eight RBD-Y antigens per 24-mer Ft nanoparticle. This work enhances our understanding of how Ft nanoparticles can be engineered to present antigens, leveraging them as a robust scaffold for producing tailored-made candidate vaccines in a timely manner.

2.
Sensors (Basel) ; 24(17)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39275600

RESUMEN

Cervical pain has been linked to increased motor unit activity, potentially associated with the initiation and progression of chronic neck pain. Therefore, this study aimed to compare the time-course changes in cervical superficial muscle activation patterns among dental students with and without neck pain throughout their initial semester of clinical training. We used an online Nordic Musculoskeletal Questionnaire for group allocation between neck pain (NP) (n = 21) and control group (CG) (n = 23). Surface electromyography (sEMG) of the sternocleidomastoid and upper bilateral trapezius was recorded before starting their clinical practice and after their first semester while performing a cranio-cervical flexion test (CCFT) in five increasing levels between 22 mmHg and 30 mmHg. After the first semester, both the CG (p < 0.001) and NP (p = 0.038) groups showed decreased sternocleidomastoid activation. The NP group exhibited a concomitant increase in upper trapezius coactivation (p < 0.001), whereas the muscle activation pattern in asymptomatic students remained unchanged (p = 0.980). During the first semester of clinical training, dental students exhibited decreased superficial flexor activity, but those with neck pain had increased co-contraction of the upper trapezius, likely to stabilize the painful segment. This altered activation pattern could be associated with further dysfunction and symptoms, potentially contributing to chronicity.


Asunto(s)
Electromiografía , Músculos del Cuello , Dolor de Cuello , Estudiantes de Odontología , Humanos , Músculos del Cuello/fisiología , Masculino , Femenino , Dolor de Cuello/fisiopatología , Estudios Longitudinales , Adulto Joven , Adulto , Encuestas y Cuestionarios
3.
Int J Mol Sci ; 25(9)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38732219

RESUMEN

Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus etiologically associated with benign and malignant diseases. Since the pathogenic mechanisms of EBV are not fully understood, understanding EBV genetic diversity is an ongoing goal. Therefore, the present work describes the genetic diversity of the lytic gene BZLF1 in a sampling of 70 EBV-positive cases from southeastern Brazil. Additionally, together with the genetic regions previously characterized, the aim of the present study was to determine the impact of viral genetic factors that may influence EBV genetic diversity. Accordingly, the phylogenetic analysis of the BZLF1 indicated two main clades with high support, BZ-A and BZ-B (PP > 0.85). Thus, the BZ-A clade was the most diverse clade associated with the main polymorphisms investigated, including the haplotype Type 1 + V3 (p < 0.001). Furthermore, the multigene phylogenetic analysis (MLA) between BZLF1 and the oncogene LMP1 showed specific clusters, revealing haplotypic segregation that previous single-gene phylogenies from both genes failed to demonstrate. Surprisingly, the LMP1 Raji-related variant clusters were shown to be more diverse, associated with BZ-A/B and the Type 2/1 + V3 haplotypes. Finally, due to the high haplotypic diversity of the Raji-related variants, the number of DNA recombination-inducing motifs (DRIMs) was evaluated within the different clusters defined by the MLA. Similarly, the haplotype BZ-A + Raji was shown to harbor a greater number of DRIMs (p < 0.001). These results call attention to the high haplotype diversity of EBV in southeast Brazil and strengthen the hypothesis of the recombinant potential of South American Raji-related variants via the LMP1 oncogene.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Variación Genética , Herpesvirus Humano 4 , Filogenia , Recombinación Genética , Herpesvirus Humano 4/genética , Humanos , Brasil , Infecciones por Virus de Epstein-Barr/virología , Infecciones por Virus de Epstein-Barr/genética , Transactivadores/genética , Masculino , Femenino , Haplotipos/genética , Adulto , Proteínas de la Matriz Viral/genética , Niño , Persona de Mediana Edad , Adolescente , Latencia del Virus/genética , Preescolar , Adulto Joven
4.
Environ Geochem Health ; 46(11): 438, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316175

RESUMEN

The concentrations of heavy metals (HMs) can be increased by various anthropogenic activities such as mining, fuel combustion, pesticide use, and urban development, which can alter the mechanisms determining their spatial variability in the environment. Determining natural concentrations, monitoring, and assessing potential ecological risks are essential in the management of pollution prevention policies and soil conservation in watersheds. The aim of this study was to determine HMs natural concentrations, establish quality reference values (QRVs), and evaluate pollution indices in a watershed-scale. Composite surface soil samples (n = 115) were collected from areas: native vegetation, pasture, perennial crops, urbanization, planted forest, annual crops, and desertification. The soil samples digestion followed the EPA 3051A, and metals determination in ICP-OES. The data were subjected to the Kruskal-Wallis test, Spearman's correlation, multivariate clustering analysis and. geostatistics. The QRVs established (75th) for the Gurgueia River watershed in descending order were (mg kg-1): V (26.16) > Cr (18.06) > Pb (6.24) > Zn (3.86) > Cu (2.66) > Ni (1.45) > Co (0.57) > Mo (0.46) > Cd (0.07). The concentrations of Cd, Co, Cr, Mo, Ni, V, and Zn in types of land and management practices were significantly increased compared to those in natural vegetation. Overall, the watershed falls into the categories of minimal to moderate enrichment, moderate to considerable contamination, and low to moderate potential ecological risk, with Cd presenting elevated values. The percentages of polluted samples ranged from 14.3 to 82.5%, indicating the need for monitoring these areas to ensure environmental quality and food safety.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados , Ríos , Contaminantes del Suelo , Metales Pesados/análisis , Brasil , Medición de Riesgo , Contaminantes del Suelo/análisis , Sedimentos Geológicos/química , Ríos/química , Suelo/química , Contaminantes Químicos del Agua/análisis
5.
Biotechnol Bioeng ; 120(9): 2588-2600, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36919374

RESUMEN

The insect cell-baculovirus expression vector system (IC-BEVS) has shown to be a powerful platform to produce complex biopharmaceutical products, such as recombinant proteins and virus-like particles. More recently, IC-BEVS has also been used as an alternative to produce recombinant adeno-associated virus (rAAV). However, little is known about the variability of insect cell populations and the potential effect of heterogeneity (e.g., stochastic infection process and differences in infection kinetics) on product titer and/or quality. In this study, transcriptomics analysis of Sf9 insect cells during the production of rAAV of serotype 2 (rAAV2) using a low multiplicity of infection, dual-baculovirus system was performed via single-cell RNA-sequencing (scRNA-seq). Before infection, the principal source of variability in Sf9 insect cells was associated with the cell cycle. Over the course of infection, an increase in transcriptional heterogeneity was detected, which was linked to the expression of baculovirus genes as well as to differences in rAAV transgenes (rep, cap and gfp) expression. Noteworthy, at 24 h post-infection, only 29.4% of cells enclosed all three necessary rAAV transgenes to produce packed rAAV2 particles, indicating limitations of the dual-baculovirus system. In addition, the trajectory analysis herein performed highlighted that biological processes such as protein folding, metabolic processes, translation, and stress response have been significantly altered upon infection. Overall, this work reports the first application of scRNA-seq to the IC-BEVS and highlights significant variations in individual cells within the population, providing insight into the rational cell and process engineering toward improved rAAV2 production in IC-BEVS.


Asunto(s)
Dependovirus , Vectores Genéticos , Animales , Dependovirus/genética , Transcriptoma/genética , Análisis de Expresión Génica de una Sola Célula , Células Sf9 , Baculoviridae/genética , Baculoviridae/metabolismo , Insectos
6.
Biotechnol Bioeng ; 120(9): 2578-2587, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37027346

RESUMEN

The majority of recombinant adeno-associated viruses (rAAV) approved for clinical use or in clinical trials areproduced by transient transfection using the HEK293 cell line. However, this platform has several manufacturing bottlenecks at commercial scales namely, low product quality (full to empty capsid ratio <20% in most rAAV serotypes), lower productivities obtained after scale-up and the high cost of raw materials, in particular of Good Manufacturing Practice grade plasmid DNA required for transfection. The HeLa-based stable cell line rAAV production system provides a robust and scalable alternative to transient transfection systems. Nevertheless, the time required to generate the producer cell lines combined with the complexity of rAAV production and purification processes still pose several barriers to the use of this platform as a suitable alternative to the HEK293 transient transfection. In this work we streamlined the cell line development and bioprocessing for the HeLaS3-based production of rAAV. By exploring this optimized approach, producer cell lines were generated in 3-4 months, and presented rAAV2 volumetric production (bulk) > 3 × 1011 vg/mL and full to empty capsids ratio (>70%) at 2 L bioreactor scale. Moreover, the established downstream process, based on ion exchange and affinity-based chromatography, efficiently eliminated process related impurities, including the Adenovirus 5 helper virus required for production with a log reduction value of 9. Overall, we developed a time-efficient and robust rAAV bioprocess using a stable producer cell line achieving purified rAAV2 yields > 1 × 1011 vg/mL. This optimized platform may address manufacturing challenges for rAAV based medicines.


Asunto(s)
Dependovirus , Vectores Genéticos , Humanos , Dependovirus/genética , Células HEK293 , Células HeLa , Transfección
7.
Biotechnol Bioeng ; 120(9): 2725-2741, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36919232

RESUMEN

Extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) act as signaling mediators of cellular responses. However, despite representing a promising alternative to cell-based therapies, clinical translation of EVs is currently limited by their lack of scalability and standardized bioprocessing. Herein, we integrated scalable downstream processing protocols with standardized expansion of large numbers of viable cells in stirred-tank bioreactors to improve EV production. Higher EV yields were linked to EV isolation by tangential flow filtration followed by size exclusion chromatography, rendering 5 times higher number of EVs comparatively to density gradient ultracentrifugation protocols. Additionally, when compared to static culture, EV manufacture in bioreactors resulted in 2.2 higher yields. Highlighting the role of operating under optimal cell culture conditions to maximize the number of EVs secreted per cell, MSCs cultured at lower glucose concentration favored EV secretion. While offline measurements of metabolites concentration can be performed, in this work, Raman spectroscopy was also applied to continuously track glucose levels in stirred-tank bioreactors, contributing to streamline the selection of optimal EV collection timepoints. Importantly, MSC-derived EVs retained their quality attributes and were able to stimulate angiogenesis in vitro, therefore highlighting their promising therapeutic potential.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Técnicas de Cultivo de Célula , Reactores Biológicos , Vesículas Extracelulares/metabolismo , Glucosa/metabolismo
8.
BMC Infect Dis ; 23(1): 846, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38041026

RESUMEN

BACKGROUND: Protection against SARS-CoV-2 is mediated by humoral and T cell responses. Pakistan faced relatively low morbidity and mortality from COVID-19 through the pandemic. To examine the role of prior immunity in the population, we studied IgG antibody response levels, virus neutralizing activity and T cell reactivity to Spike protein in a healthy control group (HG) as compared with COVID-19 cases and individuals from the pre-pandemic period (PP). METHODS: HG and COVID-19 participants were recruited between October 2020 and May 2021. Pre-pandemic sera was collected before 2018. IgG antibodies against Spike and its Receptor Binding Domain (RBD) were determined by ELISA. Virus neutralization activity was determined using a PCR-based micro-neutralization assay. T cell - IFN-γ activation was assessed by ELISpot. RESULTS: Overall, the magnitude of anti-Spike IgG antibody levels as well as seropositivity was greatest in COVID-19 cases (90%) as compared with HG (39.8%) and PP (12.2%). During the study period, Pakistan experienced three COVID-19 waves. We observed that IgG seropositivity to Spike in HG increased from 10.3 to 83.5% during the study, whilst seropositivity to RBD increased from 7.5 to 33.3%. IgG antibodies to Spike and RBD were correlated positively in all three study groups. Virus neutralizing activity was identified in sera of COVID-19, HG and PP. Spike reactive T cells were present in COVID-19, HG and PP groups. Individuals with reactive T cells included those with and without IgG antibodies to Spike. CONCLUSIONS: Antibody and T cell responses to Spike protein in individuals from the pre-pandemic period suggest prior immunity against SARS-CoV-2, most likely from cross-reactive responses. The rising seroprevalence observed in healthy individuals through the pandemic without known COVID-19 may be due to the activation of adaptive immunity from cross-reactive memory B and T cells. This may explain the more favourable COVID-19 outcomes observed in this population.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , Pakistán/epidemiología , Pandemias , Estudios Seroepidemiológicos , Glicoproteína de la Espiga del Coronavirus , Linfocitos T , Inmunoglobulina G , Ensayo de Immunospot Ligado a Enzimas , Anticuerpos Antivirales , Anticuerpos Neutralizantes , Inmunidad Humoral
9.
Mem Inst Oswaldo Cruz ; 118: e230122, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37937604

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV) is a human gammaherpesvirus etiologically linked to several benign and malignant diseases. EBV-associated malignancies exhibit an unusual global distribution that might be partly attributed to virus and host genetic backgrounds. OBJECTIVES: To assemble a new genome of EBV (CEMO3) from a paediatric Burkitt's lymphoma from Rio de Janeiro State (Southeast Brazil). In addition, to perform global phylogenetic analysis using complete EBV genomes, including CEMO3, and investigate the genetic relationship of some South American (SA) genomes through EBV subgenomic targets. METHODS: CEMO3 was sequenced through next generation sequencing and its coverage and gaps were corrected through the Sanger method. CEMO3 and 67 EBV genomes representing diverse geographic regions were evaluated through maximum likelihood phylogenetic analysis. Further, the polymorphism of subgenomic regions of some SA EBV genomes were assessed. FINDINGS: The whole bulk tumour sequencing yielded 23,217 reads related to EBV, which 172,713 base pairs of the newly EBV genome CEMO3 was assembled. The CEMO3 and most SA EBV genomes clustered within the SA subclade closely related to the African Raji strain, forming the South American/Raji clade. Notably, these Raji-related genomes exhibit significant genetic diversity, characterised by distinctive synapomorphies at some gene levels absent in the original Raji strain. CONCLUSION: The CEMO3 represents a new South American EBV genome assembled. Albeit the majority of EBV genomes from SA are Raji-related, it harbours a high diversity different from the original Raji strain.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Niño , Humanos , Herpesvirus Humano 4/genética , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/patología , Filogenia , Genoma Viral/genética , Brasil
10.
Int J Mol Sci ; 24(4)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36835047

RESUMEN

In clinical conditions such as diaphragm paralysis or mechanical ventilation, disuse-induced diaphragmatic dysfunction (DIDD) is a condition that poses a threat to life. MuRF1 is a key E3-ligase involved in regulating skeletal muscle mass, function, and metabolism, which contributes to the onset of DIDD. We investigated if the small-molecule mediated inhibition of MuRF1 activity (MyoMed-205) protects against early DIDD after 12 h of unilateral diaphragm denervation. Wistar rats were used in this study to determine the compound's acute toxicity and optimal dosage. For potential DIDD treatment efficacy, diaphragm contractile function and fiber cross-sectional area (CSA) were evaluated. Western blotting investigated potential mechanisms underlying MyoMed-205's effects in early DIDD. Our results indicate 50 mg/kg bw MyoMed-205 as a suitable dosage to prevent early diaphragmatic contractile dysfunction and atrophy following 12 h of denervation without detectable signs of acute toxicity. Mechanistically, treatment did not affect disuse-induced oxidative stress (4-HNE) increase, whereas phosphorylation of (ser632) HDAC4 was normalized. MyoMed-205 also mitigated FoxO1 activation, inhibited MuRF2, and increased phospho (ser473) Akt protein levels. These findings may suggest that MuRF1 activity significantly contributes to early DIDD pathophysiology. Novel strategies targeting MuRF1 (e.g., MyoMed-205) have potential therapeutic applications for treating early DIDD.


Asunto(s)
Diafragma , Atrofia Muscular , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas , Animales , Ratas , Diafragma/metabolismo , Diafragma/patología , Atrofia Muscular/metabolismo , Estrés Oxidativo , Ratas Wistar , Respiración Artificial/efectos adversos , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas de Motivos Tripartitos/antagonistas & inhibidores , Proteínas de Motivos Tripartitos/metabolismo
11.
J Hepatol ; 76(3): 694-725, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34715263

RESUMEN

As one of the most metabolically complex systems in the body, the liver ensures multi-organ homeostasis and ultimately sustains life. Nevertheless, during early postnatal development, the liver is highly immature and takes about 2 years to acquire and develop almost all of its functions. Different events occurring at the environmental and cellular levels are thought to mediate hepatic maturation and function postnatally. The crosstalk between the liver, the gut and its microbiome has been well appreciated in the context of liver disease, but recent evidence suggests that the latter could also be critical for hepatic function under physiological conditions. The gut-liver crosstalk is thought to be mediated by a rich repertoire of microbial metabolites that can participate in a myriad of biological processes in hepatic sinusoids, from energy metabolism to tissue regeneration. Studies on germ-free animals have revealed the gut microbiome as a critical contributor in early hepatic programming, and this influence extends throughout life, mediating liver function and body homeostasis. In this seminar, we describe the microbial molecules that have a known effect on the liver and discuss how the gut microbiome and the liver evolve throughout life. We also provide insights on current and future strategies to target the gut microbiome in the context of hepatology research.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Pruebas de Función Hepática/estadística & datos numéricos , Hígado/crecimiento & desarrollo , Homeostasis/inmunología , Homeostasis/fisiología , Humanos , Hígado/fisiología , Pruebas de Función Hepática/métodos
12.
Malar J ; 21(1): 151, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35570264

RESUMEN

BACKGROUND: Targeting the asymptomatic liver stage of Plasmodium infection through chemoprevention could become a key intervention to reduce malaria-associated incidence and mortality. METHODS: M5717, a Plasmodium elongation factor 2 inhibitor, was assessed in vitro and in vivo with readily accessible Plasmodium berghei parasites. In an animal refinement, reduction, replacement approach, the in vitro IC99 value was used to feed a Population Pharmacokinetics modelling and simulation approach to determine meaningful effective doses for a subsequent Plasmodium sporozoite-induced volunteer infection study. RESULTS: Doses of 100 and 200 mg would provide exposures exceeding IC99 in 96 and 100% of the simulated population, respectively. CONCLUSIONS: This approach has the potential to accelerate the search for new anti-malarials, to reduce the number of healthy volunteers needed in a clinical study and decrease and refine the animal use in the preclinical phase.


Asunto(s)
Antimaláricos , Malaria , Animales , Antimaláricos/farmacocinética , Antimaláricos/uso terapéutico , Humanos , Hígado/parasitología , Malaria/tratamiento farmacológico , Malaria/parasitología , Malaria/prevención & control , Factor 2 de Elongación Peptídica , Plasmodium berghei
13.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35806204

RESUMEN

microRNAs negatively regulate gene expression by blocking translation or increasing mRNA degradation. In skeletal muscle, these molecules play important roles in adaptive responses, and ongoing investigations are necessary to understand the fine-tune regulation of skeletal muscle mass. Herein we showed that skeletal muscle overexpression of miR-29c increased fiber size and force at 7 and 30 days after electrotransfer. At both time points, AKT/mTOR pathway components were downregulated, and, surprisingly, overall protein synthesis was strongly elevated at day 7, which normalized by day 30 after pCMVmiR-29c electrotransfer. These results indicate that miR-29c expression induces skeletal muscle hypertrophy and gain of function, which involves increased overall protein synthesis in spite of the deactivation of the AKT/mTOR pathway.


Asunto(s)
MicroARNs , Proteínas Proto-Oncogénicas c-akt , MicroARNs/genética , MicroARNs/metabolismo , Músculo Esquelético/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
14.
Biotechnol Bioeng ; 118(7): 2536-2547, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33764532

RESUMEN

Stable insect cell lines are emerging as an alternative to the insect cell-baculovirus expression vector system (IC-BEVS) for protein expression, benefiting from being a virus-free, nonlytic system. Still, the titers achieved are considerably lower. In this study, stable insect (Sf-9 and High Five) cells producing Gag virus-like particles (VLPs) were first adapted to grow under hypothermic culture conditions (22°C instead of standard 27°C), and then pseudotyped with a model membrane protein (influenza hemagglutinin [HA]) for expression of Gag-HA VLPs. Adaptation to lower temperature led to an increase in protein titers of up to 12-fold for p24 (as proxy for Gag-VLP) and sixfold for HA, with adapted Sf-9 cells outperforming High Five cells. Resulting Gag-HA VLPs producer Sf-9 cells were cultured to high cell densities, that is, 100 × 106 cell/ml, using perfusion (ATF® 2) in 1 L stirred-tank bioreactors. Specific p24 and HA production rates were similar to those of batch culture, enabling to increase volumetric titers by 7-8-fold without compromising the assembly of Gag-HA VLPs. Importantly, the antigen (HA) quantity in VLPs generated using stable adapted cells in perfusion was ≈5-fold higher than that from IC-BEVS, with the added benefit of being a baculovirus-free system. This study demonstrates the potential of combining stable expression in insect cells adapted to hypothermic culture conditions with perfusion for improving Gag-HA VLPs production.


Asunto(s)
Técnicas de Cultivo de Célula , Proteína p24 del Núcleo del VIH/biosíntesis , Glicoproteínas Hemaglutininas del Virus de la Influenza/biosíntesis , Proteínas Recombinantes de Fusión/biosíntesis , Animales , Proteína p24 del Núcleo del VIH/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Proteínas Recombinantes de Fusión/genética , Células Sf9 , Spodoptera
15.
Biotechnol Bioeng ; 118(9): 3522-3532, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33818758

RESUMEN

Virus-based biologicals are one of the most promising biopharmaceuticals of the 21st century medicine and play a significant role in the development of innovative therapeutic, prophylactic, and clinical applications. Oncolytic virus manufacturing scale can range from 5 L in research and development up to 50 L for clinical studies and reach hundreds of liters for commercial scale. The inherent productivity and high integration potential of periodic counter-current chromatography (PCC) offer a transversal solution to decrease equipment footprint and the reduction of several non-value-added unit operations. We report on the design of an efficient PCC process applied to the intermediate purification of oncolytic adenovirus. The developed ion-exchange chromatographic purification method was carried out using a four-column setup for three different scenarios: (i) variation in the feedstock, (ii) potential use of a post-load washing step to improve virus recovery, and (iii) stability during extended operation. Obtained virus recoveries (57%-86%) and impurity reductions (>80% DNA, and >70% total protein) match or overcome batch purification. Regarding process stability and automation, our results show that not only the dynamic control strategy used is able to suppress perturbations in the sample inlet but also allows for unattended operation in the case of ion exchange capture.


Asunto(s)
Productos Biológicos/aislamiento & purificación , Virus Oncolíticos/aislamiento & purificación , Células A549 , Distribución en Contracorriente , Humanos
16.
Biotechnol Bioeng ; 118(9): 3610-3617, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33713416

RESUMEN

Hepatocyte-like cells derived from human-induced pluripotent stem cells (hiPSC-HLC) are expected to have important applications in drug screening and regenerative medicine. However, hiPSC-HLC are difficult to produce on a large-scale to obtain relevant numbers for such applications. The aim of this study was to implement a novel integrated strategy for scalable production of hiPSC-HLC and demonstrate the applicability of dielectric spectroscopy to monitor hiPSC expansion/differentiation processes. We cultured hiPSC as three-dimensional (3D) aggregates in stirred-tank bioreactors (STB) operated in perfusion with an in situ capacitance probe. Dissolved oxygen concentration and dilution rate were controlled along the process and after 5 days of cell expansion, the hepatic differentiation was integrated in sequential steps for 28 days. The hiPSC were able to grow as 3D aggregates and the expression of hepatic markers and albumin production after differentiation confirmed that hepatocyte differentiation improved when compared to 2D culture. These hiPSC-HLC exhibited functional characteristics of hepatocytes including glycogen storage and drug metabolization capacity. Our results also show a good correlation between the cell permittivity measured online and the aggregate biovolume measured by standard offline methods, demonstrating for the first time the potential of dielectric spectroscopy to monitor hiPSC expansion and differentiation in STB.


Asunto(s)
Técnicas de Cultivo de Célula , Diferenciación Celular , Espectroscopía Dieléctrica , Hepatocitos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Hepatocitos/citología , Humanos , Células Madre Pluripotentes Inducidas/citología
17.
Biotechnol Bioeng ; 118(6): 2202-2219, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33624859

RESUMEN

Serological assays are valuable tools to study SARS-CoV-2 spread and, importantly, to identify individuals that were already infected and would be potentially immune to a virus reinfection. SARS-CoV-2 Spike protein and its receptor binding domain (RBD) are the antigens with higher potential to develop SARS-CoV-2 serological assays. Moreover, structural studies of these antigens are key to understand the molecular basis for Spike interaction with angiotensin converting enzyme 2 receptor, hopefully enabling the development of COVID-19 therapeutics. Thus, it is urgent that significant amounts of this protein became available at the highest quality. In this study, we produced Spike and RBD in two human derived cell hosts: HEK293-E6 and Expi293F™. We evaluated the impact of different and scalable bioprocessing approaches on Spike and RBD production yields and, more importantly, on these antigens' quality attributes. Using negative and positive sera collected from human donors, we show an excellent performance of the produced antigens, assessed in serologic enzyme-linked immunosorbent assay (ELISA) tests, as denoted by the high specificity and sensitivity of the test. We show robust Spike productions with final yields of approx. 2 mg/L of culture that were maintained independently of the production scale or cell culture strategy. To the best of our knowledge, the final yield of 90 mg/L of culture obtained for RBD production, was the highest reported to date. An in-depth characterization of SARS-CoV-2 Spike and RBD proteins was performed, namely the antigen's oligomeric state, glycosylation profiles, and thermal stability during storage. The correlation of these quality attributes with ELISA performance show equivalent reactivity to SARS-CoV-2 positive serum, for all Spike and RBD produced, and for all storage conditions tested. Overall, we provide straightforward protocols to produce high-quality SARS-CoV-2 Spike and RBD antigens, that can be easily adapted to both academic and industrial settings; and integrate, for the first time, studies on the impact of bioprocess with an in-depth characterization of these proteins, correlating antigen's glycosylation and biophysical attributes to performance of COVID-19 serologic tests.


Asunto(s)
Antígenos Virales/biosíntesis , Glicosilación , Glicoproteína de la Espiga del Coronavirus/biosíntesis , Frío , Ensayo de Inmunoadsorción Enzimática/normas , Congelación , Células HEK293 , Humanos , Conformación Proteica , Estabilidad Proteica , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/normas , SARS-CoV-2 , Pruebas Serológicas/normas , Glicoproteína de la Espiga del Coronavirus/normas
18.
Cells Tissues Organs ; 210(1): 66-76, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34010831

RESUMEN

The human amniotic membrane (AM) is emerging as an interesting biomaterial for regenerative medicine due to its biological and mechanical proprieties. The beneficial effects of the AM are probably related to its bioactive factors produced by local cells and stored in the stromal matrix. However, the search for a preservation method capable of preserving AM properties remains a challenge. The aim of this study was to evaluate important features of 2 anatomical regions of the human AM (reflected and placental amnion) after different preservation methods. For this purpose, human placentas were harvested and processed for AM isolation and storage at 2 different conditions: room temperature for 18 h in DMEM (fresh AM) and -80°C in DMEM/glycerol solution for 30 days (cryopreserved AM). After the storage period, the structural integrity of the membrane was assessed by histological and Picrosirius polarization analysis, cellular viability analysis was performed using the MTT assay, and the soluble proteins were quantified with the Qubit Protein Assay Kit. Both preservation protocols reduced the cell viability, mainly in the placental amnion region of the AM, but preserved the morphology of epithelial and stromal layers, as well as the organization and distribution of collagen fibers. There was a reduction in soluble proteins only in fresh AM. Importantly, the cryopreserved AM group presented the same concentration as the control group. In conclusion, the cryopreservation using DMEM/glycerol was ideal for preserving the structural integrity and soluble protein content, indicating the feasibility of this method in preserving AM for its use in regenerative medicine.


Asunto(s)
Amnios , Placenta , Supervivencia Celular , Criopreservación , Femenino , Humanos , Embarazo
19.
PLoS Comput Biol ; 16(4): e1007780, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32298259

RESUMEN

Metabolism plays an essential role in cell fate decisions. However, the methods used for metabolic characterization and for finding potential metabolic regulators are still based on characterizing cellular metabolic steady-state which is dependent on the extracellular environment. In this work, we hypothesized that the response dynamics of intracellular metabolic pools to extracellular stimuli is controlled in a cell type-specific manner. We applied principles of process dynamics and control to human induced pluripotent stem cells (hiPSC) and human neural stem cells (hNSC) subjected to a sudden extracellular glutamine step. The fold-changes of steady-states and the transient profiles of metabolic pools revealed that dynamic responses were reproducible and cell type-specific. Importantly, many amino acids had conserved dynamics and readjusted their steady state concentration in response to the increased glutamine influx. Overall, we propose a novel methodology for systematic metabolic characterization and identification of potential metabolic regulators.


Asunto(s)
Células Madre Pluripotentes Inducidas , Redes y Vías Metabólicas/fisiología , Células-Madre Neurales , Reactores Biológicos , Células Cultivadas , Biología Computacional , Espacio Extracelular/química , Espacio Extracelular/metabolismo , Glutamina/metabolismo , Glutamina/farmacología , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/metabolismo
20.
J Oral Rehabil ; 48(11): 1201-1209, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34370327

RESUMEN

BACKGROUND: Pain and anxiety contribute to decreasing quality of life related to oral health in patients with temporomandibular disorders (TMD). Evidence-based practice has shown that therapeutic and aerobic exercise programmes are adequate strategies for modifying these factors. OBJECTIVE: To assess the effects of aerobic exercise on pain, anxiety and quality of life related to oral health in patients with TMD. METHODS: Forty-five patients diagnosed with TMD were divided into three groups of 15 participants: a therapeutic exercise programme (G1, mean 26.9 ± 5.5 years), a therapeutic and aerobic exercise programme (G2, mean 26 ± 4.4 years) and an aerobic exercise programme (G3, mean 24.9 ± 3.4 years). Pain intensity was assessed using a numerical rating scale (NRS), anxiety level and quality of life related to oral health through GAD-7 and OHIP-14, respectively. These parameters were evaluated twice at baseline (T0a/T0b), ending 8-week intervention period (T1) and 8-12 weeks after ending intervention (T2). RESULTS: NRS significantly decreased in G1 (mean difference T0a/T1 = 5.2, p Ë‚ .001), G2 (mean difference T0a/T1 = 6.0, p Ë‚ .001) and G3 (mean difference T0a/T1 = 2.2, p = 0.001). OHIP-14 significantly decreased in G1 (mean difference T0a/T1 = 13.5, p Ë‚ .001) and G2 (mean difference T0a/T1 = 15.8, p ˂ 0.001) but not in G3 (mean difference T0a/T1 = 1.2, p = 0.55). There were no significant differences between groups regarding GAD-7. Between T1 and T2, there were no significant differences in variables. CONCLUSION: Therapeutic exercises and therapeutic excercises combined with aerobic exercise groups had a significant decrease in pain and oral health-related quality of life at 8 and 12 weeks. These decreases were not seen for the aerobic exercise group.


Asunto(s)
Calidad de Vida , Trastornos de la Articulación Temporomandibular , Ansiedad/terapia , Ejercicio Físico , Terapia por Ejercicio , Humanos , Dolor , Trastornos de la Articulación Temporomandibular/terapia
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