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1.
J Med Virol ; 96(6): e29713, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38874194

RESUMO

Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence is used to estimate the proportion of individuals within a population previously infected, to track viral transmission, and to monitor naturally and vaccine-induced immune protection. However, in sub-Saharan African settings, antibodies induced by higher exposure to pathogens may increase unspecific seroreactivity to SARS-CoV-2 antigens, resulting in false positive responses. To investigate the level and type of unspecific seroreactivitiy to SARS-CoV-2 in Africa, we measured immunoglobulin G (IgG), IgA, and IgM to a broad panel of antigens from different pathogens by Luminex in 602 plasma samples from African and European subjects differing in coronavirus disease 2019, malaria, and other exposures. Seroreactivity to SARS-CoV-2 antigens was higher in prepandemic African than in European samples and positively correlated with antibodies against human coronaviruses, helminths, protozoa, and especially Plasmodium falciparum. African subjects presented higher levels of autoantibodies, a surrogate of polyreactivity, which correlated with P. falciparum and SARS-CoV-2 antibodies. Finally, we found an improved sensitivity in the IgG assay in African samples when using urea as a chaotropic agent. In conclusion, our data suggest that polyreactive antibodies induced mostly by malaria are important mediators of the unspecific anti-SARS-CoV-2 responses, and that the use of dissociating agents in immunoassays could be useful for more accurate estimates of SARS-CoV-2 seroprevalence in African settings.


Assuntos
Anticorpos Antivirais , COVID-19 , Imunoglobulina G , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/epidemiologia , Anticorpos Antivirais/sangue , Estudos Soroepidemiológicos , SARS-CoV-2/imunologia , Imunoglobulina G/sangue , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Malária/epidemiologia , Malária/imunologia , Malária/sangue , Imunoglobulina M/sangue , Adulto Jovem , Idoso , Adolescente , Europa (Continente)/epidemiologia , Imunoglobulina A/sangue , Doenças Endêmicas , África/epidemiologia , África Subsaariana/epidemiologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-38530339

RESUMO

The baijiu fermentation environment hosts a variety of micro-organisms, some of which still remain uncultured and uncharacterized. In this study, the isolation, cultivation and characterization of three novel aerobic bacterial strains are described. The cells of strain REN20T were Gram-negative, strictly aerobic, motile and grew at 26-37 °C, at pH 6.0-9.0 and in the presence of 0-5.0   % (w/v) NaCl. The cells of strain REN29T were Gram-negative, strictly aerobic, motile and grew at 15-30 °C, at pH 6.0-9.0 and in the presence of 0-10.0   % (w/v) NaCl. The cells of strain REN33T were Gram-positive, strictly aerobic, motile and grew at 15-37 °C, at pH 5.0-10.0 and in the presence of 0-7.0   % (w/v) NaCl. The digital DNA-DNA hybridization and average nucleotide identity by orthology values between type strains in related genera and REN20T (20.3-36.8 % and 79.8-89.9  %), REN29T (20.3-36.8  % and 74.5-88.5  %) and REN33T (22.6-48.6  % and 75.8-84.2  %) were below the standard cut-off criteria for the delineation of bacterial species, respectively. Based on polyphasic taxonomy analysis, we propose three new species, Bosea beijingensis sp. nov. (=REN20T=GDMCC 1.2894T=JCM 35118T), Telluria beijingensis sp. nov. (=REN29T=GDMCC 1.2896T=JCM 35119T) and Agrococcus beijingensis sp. nov. (=REN33T=GDMCC 1.2898T=JCM 35164T), which were recovered during cultivation and isolation from baijiu mash.


Assuntos
Actinomycetales , Bradyrhizobiaceae , Oxalobacteraceae , Cloreto de Sódio , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , Bactérias Aeróbias
3.
Ecotoxicol Environ Saf ; 281: 116615, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38905933

RESUMO

BACKGROUND: Paraquat (PQ) is a widely used herbicide that poisons human by accident or intentional ingestion. PQ poisoning causes systemic inflammatory response syndrome (SIRS) resulting in acute lung injury (ALI) with an extremely high mortality rate. Blood trematode Schistosoma japonicum-produced cystatin (Sj-Cys) is a strong immunomodulatory protein that has been experimentally used to treat inflammation related diseases. In this study, Sj-Cys recombinant protein (rSj-Cys) was used to treat PQ-induced lung injury and the immunological mechanism underlying the therapeutic effect was investigated. METHODS: PQ-induced acute lung injury mouse model was established by intraperitoneally injection of 20 mg/kg of paraquat. The poisoned mice were treated with rSj-Cys and the survival rate was observed up to 7 days compared with the group without treatment. The pathological changes of PQ-induced lung injury were observed by examining the histochemical sections of affected lung tissue and the wet to dry ratio of lung as a parameter for inflammation and edema. The levels of the inflammation related cytokines IL-6 and TNF-α and regulatory cytokines IL-10 and TGF-ß were measured in sera and in affected lung tissue using ELISA and their mRNA levels in lung tissue using RT-PCR. The macrophages expressing iNOS were determined as M1 and those expressing Arg-1 as M2 macrophages. The effect of rSj-Cys on the transformation of inflammatory M1 to regulatory M2 macrophages was measured in affected lung tissue in vivo (EKISA and RT-PCR) and in MH-S cell line in vitro (flow cytometry). The expression levels of TLR2 and MyD88 in affected lung tissue were also measured to determine their role in the therapy of rSj-Cys on PQ-induced lung injury. RESULT: We identified that treatment with rSj-Cys significantly improved the survival rate of mice with PQ-induced lung injury from 30 % (untreated) to 80 %, reduced the pathological damage of poisoning lung tissue, associated with significantly reduced levels of proinflammatory cytokines (IL-6 from 1490 to 590 pg/ml, TNF-α from 260 to 150 pg/ml) and increased regulatory cytokines (IL-10 from360 to 550 pg/ml, and TGF-ß from 220 to 410 pg/ml) in both sera (proteins) and affected lung tissue (proteins and mRNAs). The polarization of macrophages from M1to M2 type was found to be involved in the therapeutic effect of rSj-Cys on the PQ-induced acute lung injury, possibly through inhibiting TLR2/MyD88 signaling pathway. CONCLUSIONS: Our study demonstrated the therapeutic effect of rSj-Cys on PQ poisoning caused acute lung injury by inducing M2 macrophage polarization through inhibiting TLR2/MyD88 signaling pathway. The finding in this study provides an alternative approach for the treatment of PQ poisoning and other inflammatory diseases.


Assuntos
Lesão Pulmonar Aguda , Cistatinas , Paraquat , Schistosoma japonicum , Animais , Paraquat/toxicidade , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/tratamento farmacológico , Camundongos , Herbicidas/toxicidade , Macrófagos/efeitos dos fármacos , Pulmão/patologia , Pulmão/efeitos dos fármacos , Masculino , Citocinas/metabolismo , Modelos Animais de Doenças
4.
Plant Cell Physiol ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982755

RESUMO

Improving soybean (Glycine max) seed composition by increasing the protein and oil components will add significant value to the crop and enhance environmental sustainability. Diacylglycerol acyltransferase (DGAT) catalyzes the final rate-limiting step in triacylglycerol (TAG) biosynthesis and has a major impact on seed oil accumulation. We previously identified a soybean DGAT1b variant with 14 amino acid substitutions (GmDGAT1b-MOD) that increases total oil content by 3 percentage points when overexpressed in soybean seeds. In the present study, additional GmDGAT1b variants were generated to further increase oil with a reduced number of substitutions. Variants with one to four amino acid substitutions were screened in the model systems S. cerevisiae and transient N. benthamiana leaf. Promising GmDGAT1b variants resulting in high oil accumulation in the model systems were selected for over-expression in soybeans. One GmDGAT1b variant with three novel amino acid substitutions (GmDGAT1b-3aa) increased total soybean oil to levels near the previously discovered GmDGAT1b-MOD variant. In a multiple location field trial, GmDGAT1b-3aa transgenic events had significantly increased oil and protein by up to 2.3 and 0.6 percentage points, respectively. Modeling of the GmDGAT1b-3aa protein structure provided insights into the potential function of the three substitutions. These findings will guide efforts to improve soybean oil content and overall seed composition by CRISPR editing.

5.
Plant Physiol ; 189(2): 585-594, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35191500

RESUMO

Gene targeting (GT) for precise gene insertion or swap into pre-defined genomic location has been a bottleneck for expedited soybean precision breeding. We report a robust selectable marker-free GT system in soybean, one of the most economically important crops. An efficient Oh H1-8 (Ochrobactrum haywardense H1-8)-mediated embryonic axis transformation method was used for the delivery of CRISPR-Cas9 components and donor template to regenerate T0 plants 6-8 weeks after transformation. This approach generated up to 3.4% targeted insertion of the donor sequence into the target locus in T0 plants, with ∼ 90% mutation rate observed at the genomic target site. The GT was demonstrated in two genomic sites using two different donor DNA templates without the need for a selectable marker within the template. High-resolution Southern-by-Sequencing analysis identified T1 plants with precise targeted insertion and without unintended plasmid DNA. Unlike previous low-frequency GT reports in soybean that involved particle bombardment-mediated delivery and extensive selection, the method described here is fast, efficient, reproducible, does not require a selectable marker within the donor DNA, and generates nonchimeric plants with heritable GT.


Assuntos
Glycine max , Ochrobactrum , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Marcação de Genes/métodos , Ochrobactrum/genética , Melhoramento Vegetal , Plantas Geneticamente Modificadas/genética , Glycine max/genética
6.
Langmuir ; 39(6): 2301-2311, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36719318

RESUMO

The potential of spider silk as an intriguing biological prototype for collecting water from a humid environment has attracted wide attention, and various materials with suitable structures have been engineered. Here, inspired by this phenomenon, a kind of superwetting poly(vinylidene fluoride) (PVDF) membrane with spindle-knotted structured fibers was prepared by the electrospinning method followed by oxygen plasma etching treatment. The prepared membrane presented a satisfactory separation efficiency for various oil-in-water emulsions. The cooperative effect of the special wettability property and the spindle-knot structure stimulated the emulsified oil droplets to accumulate quickly on the membrane surface. A model that explains the accumulation of emulsified oil droplets has also been developed. Furthermore, an artificial fiber comprising a micron-sized spindle-knot structure was prepared by the dip-coating method to clearly illustrate the aggregation process of the emulsified oil droplets and to verify the theoretical explanation. We hope that this study will provide new inspiration for oil/water emulsion separation techniques.

7.
Behav Res Methods ; 55(5): 2353-2366, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35931937

RESUMO

Human body movements are important for emotion recognition and social communication and have received extensive attention from researchers. In this field, emotional biological motion stimuli, as depicted by point-light displays, are widely used. However, the number of stimuli in the existing material library is small, and there is a lack of standardized indicators, which subsequently limits experimental design and conduction. Therefore, based on our prior kinematic dataset, we constructed the Dalian Emotional Movement Open-source Set (DEMOS) using computational modeling. The DEMOS has three views (i.e., frontal 0°, left 45°, and left 90°) and in total comprises 2664 high-quality videos of emotional biological motion, each displaying happiness, sadness, anger, fear, disgust, and neutral. All stimuli were validated in terms of recognition accuracy, emotional intensity, and subjective movement. The objective movement for each expression was also calculated. The DEMOS can be downloaded for free from https://osf.io/83fst/ . To our knowledge, this is the largest multi-view emotional biological motion set based on the whole body. The DEMOS can be applied in many fields, including affective computing, social cognition, and psychiatry.


Assuntos
Emoções , Felicidade , Humanos , Medo , Ira , Comunicação , Movimento , Expressão Facial
8.
J Neurochem ; 163(6): 500-516, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35997641

RESUMO

Ischemic stroke is a major global health issue. Ischemia and subsequent reperfusion results in stroke-related brain injury. Previous studies have demonstrated that nuclear-enriched abundant transcript 1 (NEATa and early growth response 1 (EGR1) are involved in ischemia reperfusion (IR) injury). In this study, we aimed to explore the roles of NEAT1/EGR1 axis as well as its downstream effector RNA binding motif protein 25 (RBM25) in cerebral IR injury. Oxygen-glucose deprivation/reperfusion (OGD/R) and middle cerebral artery occlusion (MCAO) were used to establish in vitro and in vivo models of cerebral IR injury, respectively. According to our data, NEAT1, EGR1, and RBM25 levels were elevated in OGD/R-exposed SK-N-SH and SH-SY5Y cells and cerebral cortex of MCAO mice. NEAT1, EGR1, or RBM25 knockdown effectively reduced infarct volumes and apoptosis, and improved neurological function. Mechanistically, NEAT1 directly interacted with EGR1, which restrained WW domain containing E3 ubiquitin protein ligase 1 (WWP1)-mediated ubiquitination of EGR1 and subsequently caused EGR1 accumulation. EGR1 bound to RBM25 promoter and transcriptionally activated RBM25. Rescue experiments indicated that RBM25 overexpression abolished the therapeutic effects of NEAT1 knockdown. In conclusion, this work identified a novel NEAT1/EGR1/RBM25 axis in potentiating brain injury after IR insults, suggesting a potential therapeutic target for ischemic stroke.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , MicroRNAs , Neuroblastoma , RNA Longo não Codificante , Traumatismo por Reperfusão , Humanos , Camundongos , Animais , RNA Longo não Codificante/genética , Traumatismo por Reperfusão/metabolismo , Infarto da Artéria Cerebral Média , Oxigênio/metabolismo , Apoptose/genética , Glucose/metabolismo , Motivos de Ligação ao RNA , Isquemia Encefálica/metabolismo , MicroRNAs/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
9.
Curr Issues Mol Biol ; 44(6): 2622-2634, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35735620

RESUMO

Biocontrol is a complex process, in which a variety of physiological and biochemical characteristics are altered. The cAMP signalling pathway is an important signal transduction pathway in biocontrol fungi and consists of several key components. The G-protein system contains G-protein coupled receptors (GPCRs), heterotrimeric G-proteins, adenylate cyclase (AC), cAMP-dependent protein kinase (PKA), and downstream transcription factors (TFs). The cAMP signalling pathway can regulate fungal growth, development, differentiation, sporulation, morphology, secondary metabolite production, environmental stress tolerance, and the biocontrol of pathogens. However, few reviews of the cAMP signalling pathway in comprehensive biocontrol processes have been reported. This work reviews and discusses the functions and applications of genes encoding each component in the cAMP signalling pathway from biocontrol fungi, including the G-protein system components, AC, PKA, and TFs, in biocontrol behaviour. Finally, future suggestions are provided for constructing a complete cAMP signalling pathway in biocontrol fungi containing all the components and downstream effectors involved in biocontrol behavior. This review provides useful information for the understanding the biocontrol mechanism of biocontrol fungi by utilising the cAMP signalling pathway.

10.
J Exp Bot ; 73(22): 7285-7297, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36112496

RESUMO

The majority of plant protein in the world's food supply is derived from soybean (Glycine max). Soybean is a key protein source for global animal feed and is incorporated into plant-based foods for people, including meat alternatives. Soybean protein content is genetically variable and is usually inversely related to seed oil content. ABI3-interacting protein 2 (AIP2) is an E3-RING ubiquitin ligase that targets the seed-specific transcription factor ABI3. Silencing both soybean AIP2 genes (AIP2a and AIP2b) by RNAi enhanced seed protein content by up to seven percentage points, with no significant decrease in seed oil content. The protein content enhancement did not alter the composition of the seed storage proteins. Inactivation of either AIP2a or AIP2b by a CRISPR-Cas9-mediated mutation increased seed protein content, and this effect was greater when both genes were inactivated. Transactivation assays in transfected soybean hypocotyl protoplasts indicated that ABI3 changes the expression of glycinin, conglycinin, 2S albumin, and oleosin genes, indicating that AIP2 depletion increased seed protein content by regulating activity of the ABI3 transcription factor protein. These results provide an example of a gene-editing prototype directed to improve global food security and protein availability in soybean that may also be applicable to other protein-source crops.


Assuntos
Sistemas CRISPR-Cas , Proteínas de Soja , Proteínas de Soja/genética , Sementes/genética , Fatores de Transcrição , Óleos de Plantas , Ubiquitina , Ligases
11.
Protein Expr Purif ; 190: 106003, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34688919

RESUMO

SARS-CoV-2 protein subunit vaccines are currently being evaluated by multiple manufacturers to address the global vaccine equity gap, and need for low-cost, easy to scale, safe, and effective COVID-19 vaccines. In this paper, we report on the generation of the receptor-binding domain RBD203-N1 yeast expression construct, which produces a recombinant protein capable of eliciting a robust immune response and protection in mice against SARS-CoV-2 challenge infections. The RBD203-N1 antigen was expressed in the yeast Pichia pastoris X33. After fermentation at the 5 L scale, the protein was purified by hydrophobic interaction chromatography followed by anion exchange chromatography. The purified protein was characterized biophysically and biochemically, and after its formulation, the immunogenicity was evaluated in mice. Sera were evaluated for their efficacy using a SARS-CoV-2 pseudovirus assay. The RBD203-N1 protein was expressed with a yield of 492.9 ± 3.0 mg/L of fermentation supernatant. A two-step purification process produced a >96% pure protein with a recovery rate of 55 ± 3% (total yield of purified protein: 270.5 ± 13.2 mg/L fermentation supernatant). The protein was characterized to be a homogeneous monomer that showed a well-defined secondary structure, was thermally stable, antigenic, and when adjuvanted on Alhydrogel in the presence of CpG it was immunogenic and induced high levels of neutralizing antibodies against SARS-CoV-2 pseudovirus. The characteristics of the RBD203-N1 protein-based vaccine show that this candidate is another well suited RBD-based construct for technology transfer to manufacturing entities and feasibility of transition into the clinic to evaluate its immunogenicity and safety in humans.


Assuntos
Vacinas contra COVID-19 , Expressão Gênica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Vacinas contra COVID-19/química , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/farmacologia , Humanos , Camundongos , Domínios Proteicos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , SARS-CoV-2/química , SARS-CoV-2/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/farmacologia
12.
J Integr Neurosci ; 21(6): 152, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36424757

RESUMO

BACKGROUND: This study aimed to reveal the detailed immune-related mechanisms underlying ischemic stroke (IS) and identify new immune-associated biomarkers for clinical management. METHODS: Differentially expressed genes (DEGs) between IS samples and normal controls were identified using the GSE16561 dataset. The feature genes of the immune cells were investigated using the GSE72642 dataset. Weighted correlation network analysis (WGCNA) was performed to reveal module genes, followed by an investigation of common DEGs and a functional enrichment analysis. Potential biomarkers were identified based on hub genes in protein-protein interaction networks and WGCNA. Finally, GSE158312 was used for biomarker verification. RESULTS: In total, 1230 DEGs were identified between the IS samples and normal controls. Seven clinically significant modules were identified using WGCNA. The yellow module genes were positively correlated with polymorphonuclear cells (PMNC), whereas the brown module genes were positively correlated with CD4+ T cells. Eight genes were selected as hub genes. These genes are mainly involved in functions such as the innate immune response. Upregulated TLR2 and ARG1 levels were significantly different between the two groups in the verification dataset. CONCLUSIONS: Our findings suggest ARG1 and TLR2 as novel biomarkers for IS. Upregulated TLR2 might play a role in IS development by participating in the innate immune response function.


Assuntos
AVC Isquêmico , Humanos , Receptor 2 Toll-Like , Biomarcadores , Mapas de Interação de Proteínas
13.
Protein Expr Purif ; 177: 105750, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920041

RESUMO

Cutaneous leishmaniasis is a parasitic and neglected tropical disease transmitted by the bites of sandflies. The emergence of cutaneous leishmaniasis in areas of war, conflict, political instability, and climate change has prompted efforts to develop a preventive vaccine. One vaccine candidate antigen is PpSP15, a 15 kDa salivary antigen from the sandfly Phlebotomus papatasi that facilitates the infection of the Leishmania parasite and has been shown to induce parasite-specific cell-mediated immunity. Previously, we developed a fermentation process for producing recombinant PpSP15 in Pichia pastoris and a two-chromatographic-step purification process at 100 mL scale. Here we expand the process design to the 10 L scale and examine its reproducibility by performing three identical process runs, an essential transition step towards technology transfer for pilot manufacture. The process was able to reproducibly recover 81% of PpSP15 recombinant protein with a yield of 0.75 g/L of fermentation supernatant, a purity level of 97% and with low variance among runs. Additionally, a freeze-thaw stability study indicated that the PpSP15 recombinant protein remains stable after undergoing three freeze-thaw cycles, and an accelerated stability study confirmed its stability at 37 °C for at least one month. A research cell bank for the expression of PpSP15 was generated and fully characterized. Collectively, the cell bank and the production process are ready for technology transfer for future cGMP pilot manufacturing.


Assuntos
Proteínas de Insetos/imunologia , Leishmania/imunologia , Vacinas contra Leishmaniose/imunologia , Phlebotomus/química , Proteínas e Peptídeos Salivares/imunologia , Animais , Clonagem Molecular , Feminino , Fermentação , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Leishmania/química , Vacinas contra Leishmaniose/genética , Vacinas contra Leishmaniose/metabolismo , Leishmaniose Cutânea/prevenção & controle , Peso Molecular , Phlebotomus/fisiologia , Estabilidade Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/metabolismo
14.
Parasitology ; : 1-12, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33757603

RESUMO

Trichuriasis known as whipworm infection caused by Trichuris trichiura, is a highly prevalent soil-transmitted helminthiasis in low- and middle-income countries located in tropical and subtropical areas and affecting approximately 360 million people. Children typically harbour the largest burden of T. trichiura and they are usually co-infected with other soil-transmitted helminth (STH), including Ascaris lumbricoides and hookworm. The consequences of trichuriasis, such as malnutrition and physical and cognitive growth restriction, lead to a massive health burden in endemic regions. Despite the implementation of mass drug administration of anthelminthic treatment to school-age children, T. trichiura infection remains challenging to control due to the low efficacy of current drugs as well as high rates of post-treatment re-infection. Thus, the development of a vaccine that would induce protective immunity and reduce infection rate or community faecal egg output is essential. Hurdles for human whipworm vaccine development include the lack of suitable vaccine antigen targets and animal models for human T. trichiura infection. Instead, rodent whipworm T. muris infected mouse models serve as a major surrogate for testing immunogenicity and efficacy of vaccine candidates. In this review, we summarize recent advances in animal models for T. trichiura antigen discovery and testing of vaccine candidates, while providing an overall view of the current status of T. trichiura vaccine development.

15.
Appl Microbiol Biotechnol ; 105(10): 4153-4165, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33959781

RESUMO

A SARS-CoV-2 RBD219-N1C1 (RBD219-N1C1) recombinant protein antigen formulated on Alhydrogel® has recently been shown to elicit a robust neutralizing antibody response against SARS-CoV-2 pseudovirus in mice. The antigen has been produced under current good manufacturing practices (cGMPs) and is now in clinical testing. Here, we report on process development and scale-up optimization for upstream fermentation and downstream purification of the antigen. This includes production at the 1-L and 5-L scales in the yeast, Pichia pastoris, and the comparison of three different chromatographic purification methods. This culminated in the selection of a process to produce RBD219-N1C1 with a yield of >400 mg per liter of fermentation with >92% purity and >39% target product recovery after purification. In addition, we show the results from analytical studies, including SEC-HPLC, DLS, and an ACE2 receptor binding assay that were performed to characterize the purified proteins to select the best purification process. Finally, we propose an optimized upstream fermentation and downstream purification process that generates quality RBD219-N1C1 protein antigen and is fully scalable at a low cost. KEY POINTS: • Yeast fermentation conditions for a recombinant COVID-19 vaccine were determined. • Three purification protocols for a COVID-19 vaccine antigen were compared. • Reproducibility of a scalable, low-cost process for a COVID-19 vaccine was shown. Graphical abstract.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Humanos , Camundongos , Reprodutibilidade dos Testes , SARS-CoV-2 , Saccharomycetales , Glicoproteína da Espícula de Coronavírus
16.
Mol Plant Microbe Interact ; 33(7): 902-910, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32282260

RESUMO

Clonostachys chloroleuca is a mycoparasite used for biocontrol of numerous fungal plant pathogens. Sequencing of the transcriptome of C. chloroleuca following mycoparasitization of the sclerotia of Sclerotinia sclerotiorum revealed significant upregulation of a mitogen-activated protein kinase (MAPK)-encoding gene, crmapk. Although MAPKs are known to regulate fungal growth and development, the function of crmapk in C. chloroleuca mycoparasitism is unclear. In this study, we investigated the role of crmapk in C. chloroleuca mycoparasitism through gene knockout and complementation. Deletion of crmapk had no influence on the C. chloroleuca morphological characteristics but could significantly reduce the mycoparasitic ability to sclerotia and biocontrol capacity to soybean Sclerotinia stem rot; crmapk complementation restored these abilities. Transcriptome analysis between Δcrmapk and the wild-type strain revealed numerous genes were significantly down-regulated after crmapk deletion, including cytochrome P450, transporters, and cell wall-degrading enzymes (CWDEs). Our findings indicate that crmapk influences C. chloroleuca mycoparasitism by regulation of genes controlling the activity of CWDEs or antibiotic production. This study provides a basis for further studies of the molecular mechanism of C. chloroleuca mycoparasitism.


Assuntos
Ascomicetos/patogenicidade , Agentes de Controle Biológico , Hypocreales/fisiologia , Proteínas Quinases Ativadas por Mitógeno/genética , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Genes Fúngicos , Teste de Complementação Genética , Hypocreales/genética , Doenças das Plantas/microbiologia , Glycine max/microbiologia
17.
Prostate ; 80(12): 1024-1037, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32628792

RESUMO

BACKGROUND: Dysregulation of microRNAs has performed vital gene regulatory functions in the genesis, progression, and prognosis of multiple malignant tumors. This study aimed to elucidate the regulatory mechanism of miR-196a in prostate cancer (PCa) and explore its clinical significance. METHODS: Quantitative real-time polymerase chain reaction was implemented to examine miR-196a and p27kip1 messenger RNA expression in PCa. Cell proliferation was evaluated via Cell Counting Kit-8, colony formation, and nude mouse tumorigenicity assays. Luciferase reporter assay was applied to identify target genes. p27kip1 protein expression in PCa was investigated using Western blot analysis and immunohistochemistry. RESULTS: There was a dramatic upregulation of miR-196a in PCa. Upregulated miR-196a was related to worse Gleason score (GS), later pathological stage, and poor biochemical recurrence (BCR)-free survival. In vivo and in vitro experiments exhibited that miR-196a promoted PCa proliferation and expedited G1/S-phase progression through the downregulation of p27kip1 protein. Additionally, p27kip1 protein was distinctly downregulated in PCa. Low p27kip1 protein expression had a strong correlation with increased GS and was an independent predictor of BCR after radical prostatectomy (RP). CONCLUSIONS: Excessive expression of miR-196a and subsequent downregulation of p27kip1 protein play essential roles in promoting PCa proliferation and leading to BCR after RP. miR-196a and its target p27kip1 may become novel molecular biomarkers and therapeutic targets for PCa.


Assuntos
Inibidor de Quinase Dependente de Ciclina p27/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Inibidor de Quinase Dependente de Ciclina p27/biossíntese , Inibidor de Quinase Dependente de Ciclina p27/genética , Regulação para Baixo , Células HEK293 , Humanos , Imuno-Histoquímica , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Células PC-3 , Prostatectomia/métodos , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
18.
PLoS Pathog ; 14(8): e1007273, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30153307

RESUMO

Human whipworm (Trichuris trichiura) infects approximately 1 in 15 people worldwide, representing the leading infectious cause of colitis and subsequent, inflammatory bowel disease (IBD). Current control measures focused on mass deworming have had limited success due to low drug efficacies. Vaccination would be an ideal, cost-effective strategy to induce protective immunity, leading to control of infection and transmission. Here we report the identification of whey acidic protein, a whipworm secretory protein, as a strong immunogen for inducing protective efficacy in a surrogate mouse T. muris infection model. The recombinant WAP protein (rTm-WAP49), as well as a single, highly conserved repeat within WAP (fragment 8) expressed as an Na-GST-1 fusion protein (rTm-WAP-F8+Na-GST-1), generate a strong T helper type 2 (Th2) immune response when delivered as subcutaneous vaccines formulated with Montanide ISA 720. Oral challenge with T. muris infective eggs following vaccination led to a significant reduction in worm burden of 48% by rTm-WAP49 and 33% by rTm-WAP-F8+Na-GST-1. The cellular immune correlates of protection included significant antigen-specific production of Th2 cytokines IL-4, IL-9, and IL-13 by cells isolated from the vaccine-draining inguinal lymph nodes, parasite-draining mesenteric lymph nodes, and spleen in mice vaccinated with either rTm-WAP49 or rTm-WAP-F8+Na-GST-1. The humoral immune correlates included a high antigen-specific ratio of IgG1 to IgG2a, without eliciting an IgE-mediated allergic response. Immunofluorescent staining of adult T. muris with WAP antisera identified the worm's pathogenic stichosome organ as the site of secretion of native Tm-WAP protein into the colonic mucosa. Given the high sequence conservation for the WAP proteins from T. muris and T. trichiura, the results presented here support the WAP protein to be further evaluated as a potential human whipworm vaccine candidate.


Assuntos
Imunidade , Proteínas do Leite/imunologia , Tricuríase/prevenção & controle , Trichuris/imunologia , Animais , Anticorpos Anti-Helmínticos/metabolismo , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Antígenos de Helmintos/farmacologia , Imunidade/efeitos dos fármacos , Imunidade/genética , Masculino , Camundongos , Camundongos Endogâmicos AKR , Camundongos Knockout , Camundongos SCID , Proteínas do Leite/genética , Proteínas do Leite/farmacologia , Tricuríase/imunologia , Trichuris/genética , Vacinação/métodos
19.
Arch Microbiol ; 202(7): 1749-1756, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32335717

RESUMO

ß-glucanases are widely applied in biological control, brewing and feed industries; however, there are seldom studies of ß-glucanases in probiotics. Here, ß-glucanase genes were cloned from Bacillus licheniformis, Lactobacillus fermentum and L. johnsonii. ß-glucanase genes, as blg, lfg and ljg isolated from B. licheniformis, L. fermentum and L. johnsonii were prokaryotic expressed to obtain recombinant strains BL, LF and LJ, respectively. Directed mutations in these genes were introduced by sequential error-prone PCR. Results showed that ß-glucanase activities in three mutants mblg, mlfg and mljg were 1.94-, 2.72- and 1.29-fold higher than the BL, LF and LJ, respectively. Mutation sites analysis showed substitutions at Ser370Gly and Leu395Phe in mblg; Arg169His and Asn302Ser in mlfg; Val132Met, Ser226Asn, and Asp355Gly in mljg. Spatial structural predictions revealed the numbers and positions of α-helices and ß-strands in the three mutants were altered, which might result in ß-glucanase activity increasement. Analysis of ß-glucanase properties revealed no significant differences in the optimal temperatures and pH between mutant and wild-type strains. However, mlfg and mljg exhibited greater thermal stability at 30-50 â„ƒ than the wild-type strains, and mblg improved pH stability compared with wild-type strain. This is the first report about ß-glucanase-encoding genes in L. fermentum and L. johnsonii. These findings provide an efficient way to improve the activity of ß-glucanase.


Assuntos
Bacillus , Estabilidade Enzimática/genética , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Lactobacillus , Probióticos , Bacillus/enzimologia , Bacillus/genética , Clonagem Molecular , Concentração de Íons de Hidrogênio , Lactobacillus/enzimologia , Lactobacillus/genética , Mutação , Reação em Cadeia da Polimerase , Temperatura
20.
Mediators Inflamm ; 2020: 2483435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061822

RESUMO

BACKGROUND: Previous studies have suggested that Fetuin-B seems to be a secreted adipokine related to metabolic diseases. However, the results have been inconsistent. Here, our objective is to investigate the changes in circulating Fetuin-B levels in women with polycystic ovary syndrome (PCOS) and analyze the association of Fetuin-B and insulin resistance (IR). METHODS: The current study is comprised of a cross-sectional study and a series of interventional studies. Oral glucose tolerance test (OGTT) and euglycemic-hyperinsulinemic clamp (EHC) were engaged to assess glucose tolerance and insulin sensitivity. Serum Fetuin-B levels were determined by ELISA. RESULTS: Serum Fetuin-B and TNF-α levels were markedly increased in women with PCOS compared to healthy women. Circulating Fetuin-B was positively associated with body mass index, waist-to-hip ratio, the percentage of body fat (FAT%), systolic blood pressure, triglyceride, low-density lipoprotein cholesterol, fasting blood glucose, 2 h blood glucose after glucose overload, fasting insulin, 2 h insulin after glucose overload, HOMA-insulin resistance index (HOMA-IR), the area under the curve for insulin (AUCi), AUCg, and TNF-α, while negatively associated with M value and follicular stimulating hormone (FSH). During the EHC, Fetuin-B levels were found to be significantly increased in PCOS women. After a glucose challenge, serum Fetuin-B levels in healthy women were significantly increased. Lipid infusion reduced serum Fetuin-B levels in 30 healthy subjects. After six months of glucagon-like peptide-1 receptor agonist (GLP-1RA) intervention, serum Fetuin-B concentrations in PCOS women markedly decreased following ameliorated IR. CONCLUSION: Our results indicate that Fetuin-B may be a biomarker of IR in individuals with PCOS. This trial is registered with ChiCTR-IIR-16007901.


Assuntos
Biomarcadores/sangue , Fetuína-B/metabolismo , Resistência à Insulina/fisiologia , Síndrome do Ovário Policístico/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto , Glicemia/metabolismo , LDL-Colesterol/sangue , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Estradiol/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Hormônio Luteinizante/sangue , Progesterona/sangue , Prolactina/sangue , Triglicerídeos/sangue
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