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1.
Bioconjug Chem ; 34(9): 1653-1666, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37682243

RESUMO

Coxiella burnetii is the causative agent of Q fever, for which there is yet to be an FDA-approved vaccine. This bacterial pathogen has both extra- and intracellular stages in its life cycle, and therefore both a cell-mediated (i.e., T lymphocyte) and humoral (i.e., antibody) immune response are necessary for effective eradication of this pathogen. However, most proposed vaccines elicit strong responses to only one mechanism of adaptive immunity, and some can either cause reactogenicity or lack sufficient immunogenicity. In this work, we aim to apply a nanoparticle-based platform toward producing both antibody and T cell immune responses against C. burnetii. We investigated three approaches for conjugation of the immunodominant outer membrane protein antigen (CBU1910) to the E2 nanoparticle to obtain a consistent antigen orientation: direct genetic fusion, high affinity tris-NTA-Ni conjugation to polyhistidine-tagged CBU1910, and the SpyTag/SpyCatcher (ST/SC) system. Overall, we found that the ST/SC approach yielded nanoparticles loaded with the highest number of antigens while maintaining stability, enabling formulations that could simultaneously co-deliver the protein antigen (CBU1910) and adjuvant (CpG1826) on one nanoparticle (CBU1910-CpG-E2). Using protein microarray analyses, we found that after immunization, antigen-bound nanoparticle formulations elicited significantly higher antigen-specific IgG responses than soluble CBU1910 alone and produced more balanced IgG1/IgG2c ratios. Although T cell recall assays from these protein antigen formulations did not show significant increases in antigen-specific IFN-γ production compared to soluble CBU1910 alone, nanoparticles conjugated with a CD4 peptide epitope from CBU1910 generated elevated T cell responses in mice to both the CBU1910 peptide epitope and whole CBU1910 protein. These investigations highlight the feasibility of conjugating antigens to nanoparticles for tuning and improving both humoral- and cell-mediated adaptive immunity against C. burnetii.


Assuntos
Coxiella burnetii , Febre Q , Vacinas , Animais , Camundongos , Febre Q/prevenção & controle , Antígenos de Bactérias , Anticorpos , Epitopos
2.
Am J Public Health ; 112(S9): S896-S899, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36108254

RESUMO

Native Hawaiians and other Pacific Islanders (NHPIs) across the country have experienced significant disparities because of the COVID-19 pandemic. The Pacific Alliance Against COVID-19 used a community-based participatory approach involving academic and community partners to expand sustainable COVID-19 testing capacity and mitigate the severe consequences among NHPI communities in Hawaii. We describe the approach of this one-year study, some of the results, and how the data are being used to inform next steps for the communities. Clinical Trials.gov identifier: NCT04766333. (Am J Public Health. 2022;112(S9):S896-S899. https://doi.org/10.2105/AJPH.2022.306973).


Assuntos
COVID-19 , Vacinas , Humanos , Havaí/epidemiologia , Havaiano Nativo ou Outro Ilhéu do Pacífico , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Teste para COVID-19 , Pandemias
3.
Physiol Plant ; 174(5): e13762, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36281841

RESUMO

Water stress may greatly limit plant functionality and growth. Stomatal closure and consequently reduced transpiration are considered as early and sensitive plant responses to drought and salinity stress. An important consequence of stomatal closure under water stress is the rise of leaf temperature (Tleaf ), yet Tleaf is not only fluctuating with stomatal closure. It is regulated by several plant parameters and environmental factors. Thermal imaging and different stress indices, incorporating actual leaf/crop temperature and reference temperatures, were developed in previous studies toward normalizing for effects unassociated to water stress on Tleaf , aiming at a more efficient water stress assessment. The concept of stress indices has not been extensively studied on the model plant Arabidopsis thaliana. Therefore, the aim of this study was to examine the different indices employed in previous studies in assessing rosette transpiration rate (E) in Arabidopsis plants grown under two different light environments and subjected to salinity. After salinity imposition, E was gravimetrically quantified, and thermal imaging was employed to quantify rosette (Trosette ) and artificial reference temperature (Twet, Tdry ). Trosette and several water stress indices were tested for their relation to E. Among the microclimatic growth conditions tested, RWSI1 ([Trosette - Twet ]/[Tdry - Twet ]) and RWSI2 ([Tdry - Trosette ]/[Tdry - Twet ]) were well linearly-related to E, irrespective of the light environment, while the sole use of either Twet or Tdry in different combinations with Trosette returned less accurate results. This study provides evidence that selected combinations of Trosette , Tdry , and Twet can be utilized to assess E under water stress irrespective of the light environment.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/fisiologia , Estômatos de Plantas/fisiologia , Desidratação , Secas , Folhas de Planta/fisiologia , Plantas , Transpiração Vegetal/fisiologia
4.
Proc Natl Acad Sci U S A ; 116(33): 16314-16319, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31363054

RESUMO

Critical for diverse biological processes, proteases represent one of the largest families of pharmaceutical targets. To inhibit pathogenic proteases with desired selectivity, monoclonal antibodies (mAbs) hold great promise as research tools and therapeutic agents. However, identification of mAbs with inhibitory functions is challenging because current antibody discovery methods rely on binding rather than inhibition. This study developed a highly efficient selection method for protease inhibitory mAbs by coexpressing 3 recombinant proteins in the periplasmic space of Escherichia coli-an antibody clone, a protease of interest, and a ß-lactamase modified by insertion of a protease cleavable peptide sequence. During functional selection, inhibitory antibodies prevent the protease from cleaving the modified ß-lactamase, thereby allowing the cell to survive in the presence of ampicillin. Using this method to select from synthetic human antibody libraries, we isolated panels of mAbs inhibiting 5 targets of 4 main protease classes: matrix metalloproteinases (MMP-14, a predominant target in metastasis; MMP-9, in neuropathic pain), ß-secretase 1 (BACE-1, an aspartic protease in Alzheimer's disease), cathepsin B (a cysteine protease in cancer), and Alp2 (a serine protease in aspergillosis). Notably, 37 of 41 identified binders were inhibitory. Isolated mAb inhibitors exhibited nanomolar potency, exclusive selectivity, excellent proteolytic stability, and desired biological functions. Particularly, anti-Alp2 Fab A4A1 had a binding affinity of 11 nM and inhibition potency of 14 nM, anti-BACE1 IgG B2B2 reduced amyloid beta (Aß40) production by 80% in cellular assays, and IgG L13 inhibited MMP-9 but not MMP-2/-12/-14 and significantly relieved neuropathic pain development in mice.


Assuntos
Anticorpos Monoclonais/imunologia , Peptídeo Hidrolases/genética , Inibidores de Proteases/imunologia , Proteínas Recombinantes/imunologia , Doença de Alzheimer/imunologia , Doença de Alzheimer/terapia , Sequência de Aminoácidos/genética , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/imunologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/farmacologia , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/imunologia , Aspergilose/imunologia , Aspergilose/terapia , Catepsina B/genética , Catepsina B/imunologia , Escherichia coli/genética , Humanos , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/imunologia , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/imunologia , Inibidores de Metaloproteinases de Matriz/imunologia , Inibidores de Metaloproteinases de Matriz/metabolismo , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Peptídeo Hidrolases/química , Peptídeo Hidrolases/imunologia , Periplasma/genética , Inibidores de Proteases/farmacologia , Proteólise/efeitos dos fármacos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Serina Proteases/genética , Serina Proteases/imunologia
5.
Front Ecol Environ ; 18(5): 228-234, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33424494

RESUMO

Climate-change adaptation focuses on conducting and translating research to minimize the dire impacts of anthropogenic climate change, including threats to biodiversity and human welfare. One adaptation strategy is to focus conservation on climate-change refugia (that is, areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and sociocultural resources). In this Special Issue, recent methodological and conceptual advances in refugia science will be highlighted. Advances in this emerging subdiscipline are improving scientific understanding and conservation in the face of climate change by considering scale and ecosystem dynamics, and looking beyond climate exposure to sensitivity and adaptive capacity. We propose considering refugia in the context of a multifaceted, long-term, network-based approach, as temporal and spatial gradients of ecological persistence that can act as "slow lanes" rather than areas of stasis. After years of discussion confined primarily to the scientific literature, researchers and resource managers are now working together to put refugia conservation into practice.

6.
Environ Chem ; 16(6): 482-493, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34316290

RESUMO

Because carbonaceous nanomaterials (CNMs) are expected to enter soils, the exposure implications to crop plants and plant-microbe interactions should be understood. Most investigations have been under ideal growth conditions, yet crops commonly experience abiotic and biotic stresses. Little is known how co-exposure to these environmental stresses and CNMs would cause combined effects on plants. We investigated the effects of 1000 mg kg-1 multiwalled carbon nanotubes (CNTs), graphene nanoplatelets (GNPs) and industrial carbon black (CB) on soybeans grown to the bean production stage in soil. Following seed sowing, plants became stressed by heat and infested with an insect (thrips). Consequently, all plants had similarly stunted growth, leaf damage, reduced final biomasses and fewer root nodules compared with healthy control soybeans previously grown without heat and thrips stresses. Thus, CNMs did not significantly influence the growth and yield of stressed soybeans, and the previously reported nodulation inhibition by CNMs was not specifically observed here. However, CNMs did significantly alter two leaf health indicators: the leaf chlorophyll a/b ratio, which was higher in the GNP treatment than in either the control (by 15 %) or CB treatment (by 14 %), and leaf lipid peroxidation, which was elevated in the CNT treatment compared with either the control (by 47 %) or GNP treatment (by 66 %). Overall, these results show that, while severe environmental stresses may impair plant production, CNMs (including CNTs and GNPs) in soil could additionally affect foliar health of an agriculturally important legume.

7.
Biotechnol Bioeng ; 115(11): 2673-2682, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30102763

RESUMO

Targeting effectual epitopes is essential for therapeutic antibodies to accomplish their desired biological functions. This study developed a competitive dual color fluorescence-activated cell sorting (FACS) to maturate a matrix metalloprotease 14 (MMP-14) inhibitory antibody. Epitope-specific screening was achieved by selection on MMP-14 during competition with N-terminal domain of tissue inhibitor of metalloproteinase-2 (TIMP-2) (nTIMP-2), a native inhibitor of MMP-14 binding strongly to its catalytic cleft. 3A2 variants with high potency, selectivity, and improved affinity and proteolytic stability were isolated from a random mutagenesis library. Binding kinetics indicated that the affinity improvements were mainly from slower dissociation rates. In vitro degradation tests suggested the isolated variants had half lives 6-11-fold longer than the wt. Inhibition kinetics suggested they were competitive inhibitors which showed excellent selectivity toward MMP-14 over highly homologous MMP-9. Alanine scanning revealed that they bound to the vicinity of MMP-14 catalytic cleft especially residues F204 and F260, suggesting that the desired epitope was maintained during maturation. When converted to immunoglobulin G, B3 showed 5.0 nM binding affinity and 6.5 nM inhibition potency with in vivo half-life of 4.6 days in mice. In addition to protease inhibitory antibodies, the competitive FACS described here can be applied for discovery and engineering biosimilars, and in general for other circumstances where epitope-specific modulation is needed.


Assuntos
Anticorpos/isolamento & purificação , Afinidade de Anticorpos , Avaliação Pré-Clínica de Medicamentos/métodos , Epitopos/imunologia , Fatores Imunológicos/isolamento & purificação , Metaloproteinase 14 da Matriz/imunologia , Inibidores de Metaloproteinases de Matriz/isolamento & purificação , Animais , Anticorpos/imunologia , Sítios de Ligação , Citometria de Fluxo/métodos , Meia-Vida , Fatores Imunológicos/imunologia , Cinética , Metaloproteinase 14 da Matriz/metabolismo , Camundongos , Mutagênese , Ligação Proteica
8.
Plant Cell Physiol ; 58(8): 1339-1349, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961989

RESUMO

Light is most important to plants as it fuels photosynthesis and provides clues about the environment. If provided in unnatural long photoperiods, however, it can be harmful and even lethal. Tomato (Solanum lycopersicum), for example, develops mottled chlorosis and necrosis when exposed to continuous light. Understanding the mechanism of these injuries is valuable, as important pathways regulating photosynthesis, such as circadian, retrograde and light signaling pathways are probably involved. Here, we use non-targeted metabolomics and transcriptomics analysis as well as hypothesis-driven experiments with continuous light-tolerant and -sensitive tomato lines to explore the long-standing proposed role of carbohydrate accumulation in this disorder. Analysis of metabolomics and transcriptomics data reveals a clear effect of continuous light on sugar metabolism and photosynthesis. A strong negative correlation between sucrose and starch content with the severity of continuous light-induced damage quantified as the maximum quantum efficiency of PSII (Fv/Fm) was found across several abnormal light/dark cycles, supporting the hypothesis that carbohydrates play an important role in the continuous light-induced injury. We postulate that the continuous light-induced injury in tomato is caused by down-regulation of photosynthesis, showing characteristics of both cytokinin-regulated senescence and light-modulated retrograde signaling. Molecular mechanisms linking carbohydrate accumulation with down-regulation of carbon-fixing enzymes are discussed.


Assuntos
Complexo de Proteína do Fotossistema II/metabolismo , Solanum lycopersicum/fisiologia , Amido/metabolismo , Sacarose/metabolismo , Metabolismo dos Carboidratos , Ciclo do Carbono/fisiologia , Citocininas/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Genótipo , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
New Phytol ; 209(3): 945-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26443127

RESUMO

Understanding and predicting plant response to disturbance is of paramount importance in our changing world. Resprouting ability is often considered a simple qualitative trait and used in many ecological studies. Our aim is to show some of the complexities of resprouting while highlighting cautions that need be taken in using resprouting ability to predict vegetation responses across disturbance types and biomes. There are marked differences in resprouting depending on the disturbance type, and fire is often the most severe disturbance because it includes both defoliation and lethal temperatures. In the Mediterranean biome, there are differences in functional strategies to cope with water deficit between resprouters (dehydration avoiders) and nonresprouters (dehydration tolerators); however, there is little research to unambiguously extrapolate these results to other biomes. Furthermore, predictions of vegetation responses to changes in disturbance regimes require consideration not only of resprouting, but also other relevant traits (e.g. seeding, bark thickness) and the different correlations among traits observed in different biomes; models lacking these details would behave poorly at the global scale. Overall, the lessons learned from a given disturbance regime and biome (e.g. crown-fire Mediterranean ecosystems) can guide research in other ecosystems but should not be extrapolated at the global scale.


Assuntos
Germinação , Internacionalidade , Secas , Modelos Biológicos , Plantas
10.
Cultur Divers Ethnic Minor Psychol ; 22(3): 341-349, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26168163

RESUMO

OBJECTIVES: The aim of the present study was to propose and examine a pathway to emotional distress in African Americans with juvenile court contact (N = 213; Male = 71%; MAge = 15, SDAge = 1.47). METHOD: The model included direct and indirect effects of parent attachment and empathy, as well as the direct effects of pro-social and aggressive behavior, on emotional distress, CFI = .99, TLI = .95, χ²(1) = 2.60 p = .11, and RMSEA = .09. RESULTS: This model explained 49% of variability of scores for emotional distress. Overall, aggressive behavior had the strongest relationship with emotional distress (ß = .63), followed by parent attachment (ß = -.38). In contrast, empathy (ß = .12) and pro-social behavior (ß = .17) were not related to emotional distress scores. A second model that included males and females simultaneously, without equality constraints, revealed substantive gender differences, CFI = .99, TLI = .91, χ²(2) = 4.63 p = .10, and RMSEA = .11. CONCLUSIONS: Results are discussed in the context of therapeutic jurisprudence, and recommendations are proposed for providers of court-ordered interventions (i.e., therapy and probation supervision). (PsycINFO Database Record


Assuntos
Emoções/fisiologia , Psiquiatria Legal/métodos , Estresse Psicológico/psicologia , Adolescente , Negro ou Afro-Americano/psicologia , Agressão/psicologia , Criança , Empatia/fisiologia , Feminino , Humanos , Masculino , Comportamento Social , Inquéritos e Questionários
11.
Planta ; 241(1): 285-90, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25399350

RESUMO

Continuous light induces a potentially lethal injury in domesticated tomato (Solanum lycopersicum) plants. Recently, continuous-light tolerance was reported in several wild tomato species, yet the molecular mechanisms underpinning tolerance/sensitivity are still elusive. Here, we investigated from which part of the plant continuous-light tolerance originates and whether this trait acts systemically within the plant. By exposing grafted plants bearing both tolerant and sensitive shoots, the trait was functionally located in the shoot rather than the roots. Additionally, an increase in continuous-light tolerance was observed in sensitive plants when a continuous-light-tolerant shoot was grafted on it. Cultivation of greenhouse tomatoes under continuous light promises high yield increases. Our results show that to pursuit this, the trait should be bred into scion rather than rootstock lines. In addition, identifying the nature of the signal/molecule(s) and/or the mechanism of graft-induced, continuous-light tolerance can potentially result in a better understanding of important physiological processes like long-distance signaling.


Assuntos
Adaptação Fisiológica/efeitos da radiação , Produção Agrícola/métodos , Luz , Solanum lycopersicum/efeitos da radiação , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Padrões de Herança/genética , Padrões de Herança/fisiologia , Padrões de Herança/efeitos da radiação , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Raízes de Plantas/efeitos da radiação , Brotos de Planta/genética , Brotos de Planta/fisiologia , Brotos de Planta/efeitos da radiação , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos da radiação
12.
Glob Chang Biol ; 20(3): 893-907, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24375846

RESUMO

We examined postfire regeneration of chaparral shrubs during an intense drought. This study focused on the demography and physiology of shrub species that resprout from a basal lignotuber following fire. We found significant levels of resprout mortality when intense drought occurred in the year following fire during the period of shrub recovery. Three of the seven sampled resprouting species had the greatest or near greatest levels of mortality ever recorded when compared to previous studies. Most shrub mortality occurred during the drought after individuals had resprouted (i.e. individuals survived fire, resprouted and then subsequently died). Physiological measurements of species with high mortality suggested that resprout stems were highly embolized and xylem hydraulic conductivities were close to zero during the peak of the drought. In addition, lignotubers of two of the three species experiencing high mortality were depleted of starch. Population densities of most shrub species declined after the drought compared with their prefire levels, with the exception of one drought tolerant obligate seeding species. Resprouting shrub species may deplete their carbohydrate reserves during the resprouting process, making them particularly vulnerable to drought because of the need to transpire water to acquire the CO2 that is used to supply energy to a large respiring root system. Drought appears to interact with fire by altering postfire shrub recovery and altering species abundances and composition of chaparral communities.


Assuntos
Secas , Incêndios , Fenômenos Fisiológicos Vegetais , California , Metabolismo dos Carboidratos , Estômatos de Plantas/metabolismo , Tubérculos/metabolismo , Água/metabolismo , Xilema/fisiologia
13.
bioRxiv ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38260543

RESUMO

The C4 photosynthetic pathway provided a major advantage to plants growing in hot, dry environments, including the ancestors of our most productive crops. Two traits were essential for the evolution of this pathway: increased vein density and the functionalization of bundle sheath cells for photosynthesis. Although GRAS transcriptional regulators, including SHORT ROOT (SHR), have been implicated in mediating leaf patterning in both C3 and C4 species, little is known about what controls the specialized features of the cells that mediate C4 metabolism and physiology. We show in the model monocot, Setaria viridis, that SHR regulates components of multiple cell identities, including chloroplast biogenesis and photosynthetic gene expression in bundle sheath cells, a central feature of C4 plants. Furthermore, we found that it also contributes to the two-cell compartmentalization of the characteristic four-carbon shuttle pathway. Disruption of SHR function clearly reduced photosynthetic capacity and seed yield in mutant plants under heat stress. Together, these results show how cell identities are remodeled by SHR to host the suite of traits characteristic of C4 regulation, which are a main engineering target in non-C4 crops to improve climate resilience.

14.
ACS Infect Dis ; 9(2): 239-252, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36607269

RESUMO

The vast majority of seasonal influenza vaccines administered each year are derived from virus propagated in eggs using technology that has changed little since the 1930s. The immunogenicity, durability, and breadth of response would likely benefit from a recombinant nanoparticle-based approach. Although the E2 protein nanoparticle (NP) platform has been previously shown to promote effective cell-mediated responses to peptide epitopes, it has not yet been reported to deliver whole protein antigens. In this study, we synthesized a novel maleimido tris-nitrilotriacetic acid (NTA) linker to couple protein hemagglutinin (HA) from H1N1 influenza virus to the E2 NP, and we evaluated the HA-specific antibody responses using protein microarrays. We found that recombinant H1 protein alone is immunogenic in mice but requires two boosts for IgG to be detected and is strongly IgG1 (Th2) polarized. When conjugated to E2 NPs, IgG2c is produced leading to a more balanced Th1/Th2 response. Inclusion of the Toll-like receptor 4 agonist monophosphoryl lipid A (MPLA) significantly enhances the immunogenicity of H1-E2 NPs while retaining the Th1/Th2 balance. Interestingly, broader homo- and heterosubtypic cross-reactivity is also observed for conjugated H1-E2 with MPLA, compared to unconjugated H1 with or without MPLA. These results highlight the potential of an NP-based delivery of HA for tuning the immunogenicity, breadth, and Th1/Th2 balance generated by recombinant HA-based vaccination. Furthermore, the modularity of this protein-protein conjugation strategy may have utility for future vaccine development against other human pathogens.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Nanopartículas , Humanos , Animais , Camundongos , Influenza Humana/prevenção & controle , Hemaglutininas , Formação de Anticorpos , Anticorpos Antivirais , Proteínas Recombinantes
15.
Biomater Sci ; 11(2): 596-610, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36476811

RESUMO

Cancer vaccine immunotherapy facilitates the immune system's recognition of tumor-associated antigens, and the biomolecular design of these vaccines using nanoparticles is one important approach towards obtaining strong anti-tumor responses. Following activation of dendritic cells (DCs), a robust CD8+ T cell-mediated adaptive immune response is critical for tumor elimination. While the role of efficient antigen-presenting myeloid DCs (mDCs) is conventionally attributed towards vaccine efficacy, participation by highly cytokine-producing plasmacytoid DCs (pDCs) is less understood and is often overlooked. We examined vaccines based on the E2 protein nanoparticle platform that delivered encapsulated TLR9 agonist bacterial-like DNA (CpG1826 or CpG1018) or TLR7 agonist viral ssRNA to determine their efficacy over free agonists in activating both mDCs and pDCs for antigen presentation. Although mDCs were only activated by nanoparticle-encapsulated TLR9 agonists, pDCs were activated by all the individually tested constructs, and CpG1826 was shown to induce pDC cytokine production. Transfer of secreted factors from pDCs that were stimulated with a vaccine formulation comprising peptide antigen and CpG1826 enhanced mDC display of the antigen, particularly when delivered in nanoparticles. Only when treated with nanoparticle-conjugated vaccine could pDCs secrete factors to induce antigen display on naïve mDCs. These results reveal that pDCs can aid mDCs, highlighting the importance of activating both pDCs and mDCs in designing effective cancer vaccines, and demonstrate the advantage of using nanoparticle-based vaccine delivery.


Assuntos
Neoplasias , Vacinas , Humanos , Receptor Toll-Like 9/metabolismo , Citocinas/metabolismo , Linfócitos T CD8-Positivos , Neoplasias/metabolismo , Células Dendríticas
16.
Chemosphere ; 313: 137383, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36436581

RESUMO

Primary sludge (PS) is associated with public health and environmental risks, so regulations focus on reducing the pathogenic and heavy metal contents of the treated material (biosolids), intended for soil amendments and land reclamation. The regulations set limits for Escherichia coli (or fecal coliforms), Salmonella spp., helminth eggs and enterovirus. However, the potential risk due to antibiotic resistant bacteria (ARB) and other human potential pathogenic bacteria (HPB) are not considered. In this work, three sludge treatment processes, having in common an anaerobic digestion step, were applied to assess the removal of regulated bacteria (fecal coliforms, Salmonella spp), ARB and HPB. The treatment arrangements, fed with PS from a full-scale wastewater treatment plant were: 1) Mesophilic anaerobic digestion followed by alkaline stabilization post-treatment (MAD-CaO); 2) Thermophilic anaerobic digestion (TAD) and, 3) Pre-treatment (mild thermo-hydrolysis) followed by TAD (PT-TAD). The results address the identification, quantification (colony forming units) and taxonomic characterization of ARB resistant to ß-lactams and vancomycin, as well as the taxonomic characterization of HPB by sequencing with PacBio. In addition, quantification based on culture media of fecal coliforms and Salmonella spp. is presented. The capabilities and limitations of microbiological and metataxonomomic analyses based on PacBio sequencing are discussed, emphasizing that they complement each other. Genus Aeromonas, Acinetobacter, Citrobacter, Enterobacter, Escherichia, Klebsiella, Ochrobactrum, Pseudomonas and Raoultella, among others, were found in the PS, which are of clinical or environmental importance, being either HPB, HPB-ARB, or non-pathogenic ARB with the potentiality of horizontal gene transfer. Based on the analysis of fecal coliforms and Salmonella spp., the three processes produced class A (highest) biosolids, suitable for unrestricted agriculture applications. Mild thermo-hydrolisis was effective in decreasing ARB cultivability, but it reappeared after the following TAD. O. intermedium (HPB-ARB) was enriched in MAD and TAD while Laribacter hongkongensis (HPB) did persist after the applied treatments.


Assuntos
Antagonistas de Receptores de Angiotensina , Esgotos , Humanos , Esgotos/microbiologia , Anaerobiose , Hidrólise , Biossólidos , Inibidores da Enzima Conversora de Angiotensina , Bactérias , Salmonella , Escherichia coli , Resistência Microbiana a Medicamentos , Digestão , Bactérias Anaeróbias
17.
Front Bioeng Biotechnol ; 11: 1202126, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485316

RESUMO

The outbreak of COVID-19, a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is regarded as the most severe of the documented coronavirus pandemics. The measurement and monitoring of SARS-CoV-2 antibody levels by serological tests are relevant for a better epidemiological and clinical understanding of COVID-19. The aim of this work was to design a method called the SARS-CoV-2 antibody detection method (SARS-CoV-2 AbDM) for fluorescence immunodetection of anti-SARS-CoV-2 IgG and IgM on both plate and microfluidic chip. For this purpose, a system with magnetic beads that immobilize the antigen (S protein and RBD) on its surface was used to determine the presence and quantity of antibodies in a sample in a single reaction. The SARS-CoV-2 AbDM led to several advantages in the performance of the tests, such as reduced cost, possibility of performing isolated or multiple samples, potential of multiplex detection, and capacity to detect whole blood samples without losing resolution. In addition, due to the microfluidic chip in conjunction with the motorized actuated platform, the time, sample quantity, and operator intervention during the process were reduced. All these advantages suggest that the SARS-CoV-2 AbDM has the potential to be developed as a PoC that can be used as a tool for seroprevalence monitoring, allowing a better understanding of the epidemiological and clinical characteristics of COVID-19 and contributing to more effective and ethical decision-making in strategies to fight against the COVID-19 pandemic.

18.
Mater Today Bio ; 17: 100455, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36304975

RESUMO

Bioluminescence imaging has advantages over fluorescence imaging, such as minimal photobleaching and autofluorescence, and greater signal-to-noise ratios in many complex environments. Although significant achievements have been made in luciferase engineering for generating bright and stable reporters, the full capability of luciferases for nanoparticle tracking has not been comprehensively examined. In biocatalysis, enhanced enzyme performance after immobilization on nanoparticles has been reported. Thus, we hypothesized that by assembling luciferases onto a nanoparticle, the resulting complex could lead to substantially improved imaging properties. Using a modular bioconjugation strategy, we attached NanoLuc (NLuc) or Akaluc bioluminescent proteins to a protein nanoparticle platform (E2), yielding nanoparticles NLuc-E2 and Akaluc-E2, both with diameters of ∼45 â€‹nm. Although no significant differences were observed between different conditions involving Akaluc and Akaluc-E2, free NLuc at pH 5.0 showed significantly lower emission values than free NLuc at pH 7.4. Interestingly, NLuc immobilization on E2 nanoparticles (NLuc-E2) emitted increased luminescence at pH 7.4, and at pH 5.0 showed over two orders of magnitude (>200-fold) higher luminescence (than free NLuc), expanding the potential for imaging detection using the nanoparticle even upon endocytic uptake. After uptake by macrophages, the resulting luminescence with NLuc-E2 nanoparticles was up to 7-fold higher than with free NLuc at 48 â€‹h. Cells incubated with NLuc-E2 could also be imaged using live bioluminescence microscopy. Finally, biodistribution of nanoparticles into lymph nodes was detected through imaging using NLuc-E2, but not with conventionally-labeled fluorescent E2. Our data demonstrate that NLuc-bound nanoparticles have advantageous properties that can be utilized in applications ranging from single-cell imaging to in vivo biodistribution.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33164326

RESUMO

Infectious diseases are a major threat to global human health, yet prophylactic treatment options can be limited, as safe and efficacious vaccines exist only for a fraction of all diseases. Notably, devastating diseases such as acquired immunodeficiency syndrome (AIDS) and coronavirus disease of 2019 (COVID-19) currently do not have vaccine therapies. Conventional vaccine platforms, such as live attenuated vaccines and whole inactivated vaccines, can be difficult to manufacture, may cause severe side effects, and can potentially induce severe infection. Subunit vaccines carry far fewer safety concerns due to their inability to cause vaccine-based infections. The applicability of protein nanoparticles (NPs) as vaccine scaffolds is promising to prevent infectious diseases, and they have been explored for a number of viral, bacterial, fungal, and parasitic diseases. Many types of protein NPs exist, including self-assembling NPs, bacteriophage-derived NPs, plant virus-derived NPs, and human virus-based vectors, and these particular categories will be covered in this review. These vaccines can elicit strong humoral and cellular immune responses against specific pathogens, as well as provide protection against infection in a number of animal models. Furthermore, published clinical trials demonstrate the promise of applying these NP vaccine platforms, which include bacteriophage-derived NPs, in addition to multiple viral vectors that are currently used in the clinic. The continued investigations of protein NP vaccine platforms are critical to generate safer alternatives to current vaccines, advance vaccines for diseases that currently lack effective prophylactic therapies, and prepare for the rapid development of new vaccines against emerging infectious diseases. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Biology-Inspired Nanomaterials > Protein and Virus-Based Structures.


Assuntos
COVID-19/prevenção & controle , Doenças Transmissíveis Emergentes/prevenção & controle , Nanomedicina/métodos , Nanopartículas/química , Proteínas/química , Vacinas/química , Proteínas Virais/química , Animais , Bacteriófagos/metabolismo , Escherichia coli/virologia , Proteínas de Choque Térmico/química , Humanos , Imunidade Celular , Imunidade Humoral , Proteínas Recombinantes/química , SARS-CoV-2 , Vírus
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4998-5004, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892330

RESUMO

MIT's Emergency-Vent Project was launched in March 2020 to develop safe guidance and a reference design for a bridge ventilator that could be rapidly produced in a distributed manner worldwide. The system uses a novel servo-based robotic gripper to automate the squeezing of a manual resuscitator bag evenly from both sides to provide ventilation according to clinically specified parameters. In just one month, the team designed and built prototype ventilators, tested them in a series of porcine trials, and collaborated with industry partners to enable mass production. We released the design, including mechanical drawings, design spreadsheets, circuit diagrams, and control code into an open source format and assisted production efforts worldwide.Clinical relevance- This work demonstrated the viability of automating the compression of a manual resuscitator bag, with pressure feedback, to provide bridge ventilation support.


Assuntos
COVID-19 , Animais , Humanos , Respiração , Ressuscitação , SARS-CoV-2 , Suínos , Ventiladores Mecânicos
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