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1.
Front Immunol ; 12: 706186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484202

RESUMO

Background: Sargramostim [recombinant human granulocyte-macrophage colony-stimulating factor (rhu GM-CSF)] was approved by US FDA in 1991 to accelerate bone marrow recovery in diverse settings of bone marrow failure and is designated on the list of FDA Essential Medicines, Medical Countermeasures, and Critical Inputs. Other important biological activities including accelerating tissue repair and modulating host immunity to infection and cancer via the innate and adaptive immune systems are reported in pre-clinical models but incompletely studied in humans. Objective: Assess safety and efficacy of sargramostim in cancer and other diverse experimental and clinical settings. Methods and Results: We systematically reviewed PubMed, Cochrane and TRIP databases for clinical data on sargramostim in cancer. In a variety of settings, sargramostim after exposure to bone marrow-suppressing agents accelerated hematologic recovery resulting in fewer infections, less therapy-related toxicity and sometimes improved survival. As an immune modulator, sargramostim also enhanced anti-cancer responses in solid cancers when combined with conventional therapies, for example with immune checkpoint inhibitors and monoclonal antibodies. Conclusions: Sargramostim accelerates hematologic recovery in diverse clinical settings and enhances anti-cancer responses with a favorable safety profile. Uses other than in hematologic recovery are less-well studied; more data are needed on immune-enhancing benefits. We envision significantly expanded use of sargramostim in varied immune settings. Sargramostim has the potential to reverse the immune suppression associated with sepsis, trauma, acute respiratory distress syndrome (ARDS) and COVID-19. Further, sargramostim therapy has been promising in the adjuvant setting with vaccines and for anti-microbial-resistant infections and treating autoimmune pulmonary alveolar proteinosis and gastrointestinal, peripheral arterial and neuro-inflammatory diseases. It also may be useful as an adjuvant in anti-cancer immunotherapy.


Assuntos
COVID-19/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Imunoterapia , Neoplasias/tratamento farmacológico , COVID-19/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , SARS-CoV-2/efeitos dos fármacos
2.
PLoS One ; 16(9): e0257351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34520491

RESUMO

COVID-19 is the name of the acute respiratory disease caused by the new coronavirus SARS-CoV-2, a close relative of those that caused the severe outbreaks of SARS and MERS several years ago. Since first appearance on December of 2019, the COVID-19 pandemic has cause extremely high levels of mortality, morbidity, global economic breakdown, and the consequent human suffering. The main diagnostic test for the confirmation of symptomatic individuals is the detection of viral RNA by reverse transcriptase-quantitative real time PCR (RT-PCR). Additionally, serology techniques, such as ELISA are useful to measure the antibodies produced in humans after contact with the virus, as well as the direct presence of viral antigens. In this study we aim to assemble and evaluate four ELISA assays to measure the presence of IgG or IgM specific for the viral Spike protein in COVID-19 patients, using either the full recombinant SARS-CoV-2 Spike protein or the fragment corresponding to the receptor binding domain. As a control, we analyzed a group of pre-pandemic serum samples obtained before 2017. Strong reactivity was observed against both antigens. A few pre-pandemic samples displayed high OD values, suggesting the possibility of some cross reactivity. All four assays show very good repeatability, both intra- and inter-assay. Receiver operating characteristic analysis allowed the definition of cutoffs and evaluation of performance for each ELISA by estimation of the area under the curve. This performance parameter was high for all tests (AUC range: 0.98-0.99). Multiple comparisons between tests revealed no significant difference between each other (P values: 0.24-0.95). Our results show that both antigens are effective to detect both specific IgG and IgM antibodies, with high sensitivity (range 0.92-0.99), specificity (range 0.93-0.97) and congruence with the RT-PCR test (Cohen´s Kappa range 0.87-0.93). These assays will allow health authorities to have a new tool to estimate seroprevalence, in order to manage and improve the severe sanitary situation caused by this virus.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , COVID-19/epidemiologia , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19 , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Panamá/epidemiologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética
3.
Appl Microbiol Biotechnol ; 105(18): 6607-6626, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34468804

RESUMO

Bacillus subtilis is a well-characterized Gram-positive bacterium and a valuable host for recombinant protein production because of its efficient secretion ability, high yield, and non-toxicity. Here, we comprehensively review the recent studies on recombinant protein production in B. subtilis to update and supplement other previous reviews. We have focused on several aspects, including optimization of B. subtilis strains, enhancement and regulation of expression, improvement of secretion level, surface display of proteins, and fermentation optimization. Among them, optimization of B. subtilis strains mainly involves undirected chemical/physical mutagenesis and selection and genetic manipulation; enhancement and regulation of expression comprises autonomous plasmid and integrated expression, promoter regulation and engineering, and fine-tuning gene expression based on proteases and molecular chaperones; improvement of secretion level predominantly involves secretion pathway and signal peptide screening and optimization; surface display of proteins includes surface display of proteins on spores or vegetative cells; and fermentation optimization incorporates medium optimization, process condition optimization, and feeding strategy optimization. Furthermore, we propose some novel methods and future challenges for recombinant protein production in B. subtilis.Key points• A comprehensive review on recombinant protein production in Bacillus subtilis.• Novel techniques facilitate recombinant protein expression and secretion.• Surface display of proteins has significant potential for different applications.


Assuntos
Bacillus subtilis , Proteínas de Bactérias , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Chaperonas Moleculares , Sinais Direcionadores de Proteínas , Proteínas Recombinantes/genética
4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(9): 866-872, 2021 Sep 24.
Artigo em Chinês | MEDLINE | ID: mdl-34530593

RESUMO

Objective: To compare the efficacy and safety of pro-urokinase and reteplase in the treatment of patients with acute ST elevation myocardial infarction (STEMI). Methods: STEMI patients, who received intravenous thrombolytic therapy in Henan STEMI registry between September 2016 and August 2018, were eligible for this study. A total of 5479 patients from 66 hospitals were screened and patients were divided into pro-urokinase group (n=638) and reteplase group (n=702) according to thrombolytic drugs. Data including patient demographics, risk factors, medical histories, patient information at admission, in-hospital treatment, time delays, and clinical events were collected. The clinical recanalization rate, in-hospital mortality, in-hospital death or treatment withdrawal, in-hospital main adverse cardiovascular and cerebrovascular events (MACCE, death or treatment withdrawal, congestive heart failure, reinfarction and ischemic stroke) and post-thrombolysis bleeding were compared between the two groups. Bleeding events were evaluated with Bleeding Academic Research Consortium (BARC) criteria. Results: The median age [61.8 (53.2, 69.0) vs. 62.6 (52.1, 69.8), P=0.833] or the proportion of women [23.0% (147/638) vs. 25.1% (176/702), P=0.385] were similar between the pro-urokinase and reteplase groups. Clinical recanalization rates were similar between the pro-urokinase and reteplase groups [82.1% (524/638) vs. 84.9% (596/702), P=0.172], and there was no difference in the median time from onset to thrombolysis [194.5 (135.0,290.0) min vs. 190 (126.0,292.0) min, P=0.431] and the median recanalization time [95 (67.5,120.0) min vs. 95 (71.0,119.0) min, P=0.561] between the two groups. There was no significant difference in in-hospital mortality [5.5% (35/638) vs. 5.1% (36/702), P =0.770], in-hospital all-cause mortality, treatment withdrawal [8.9% (57/638) vs.7.7% (54/702), P=0.410], and in-hospital MACCE [13.0% (83/638) vs. 10.4% (73/702), P=0.137] between pro-urokinase and reteplase groups. However, the incidence of post-thrombolysis bleeding was significantly higher in reteplase group than in pro-urokinase group [7.8% (55/702) vs. 3.8% (24/638), P=0.002]. Further analysis found that the incidence of oral bleeding and the BARC grades 1-2 bleeding were significantly higher in reteplase group than in pro-urokinase group, whereas the incidence of cerebral hemorrhage was similar between the two groups [0.6% (4/638) vs. 0.4% (3/702), P=0.715]. The comparison of efficacy and safety outcomes between the two groups after adjusting for baseline characteristics using general linear mixed models was consistent with those before the adjustment. There was no significant difference in in-hospital mortality, in-hospital death or treatment withdrawal, in-hospital MACCE after adjusting for baseline characteristics and post-thrombolysis bleeding between the two groups. Conclusions: Pro-urokinase and reteplase have similar clinical efficacy in the treatment of STEMI. In terms of safety, the incidence of cerebral hemorrhage is similar, while the incidence of BARC grades 1-2 bleeding and oral bleeding is higher in reteplase group than in pro-urokinase group, which has no impact on in-hospital outcomes.


Assuntos
Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Feminino , Fibrinolíticos/uso terapêutico , Mortalidade Hospitalar , Humanos , Infarto do Miocárdio/tratamento farmacológico , Proteínas Recombinantes , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual , Resultado do Tratamento , Ativador de Plasminogênio Tipo Uroquinase
5.
BMJ Case Rep ; 14(9)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531230

RESUMO

Factor XIII (FXIII) is a thrombin-activated protransglutaminase that plays a key role in blood clot formation. Congenital FXIII A-subunit deficiency represents a rare bleeding disorder that affects one in 2-3 million individuals worldwide and is treated with recombinant FXIII (rFXIII). However, due to the rarity of the disease, clinicians are often left to weigh individual variation in FXIII activity and/or symptoms to optimally guide dosing. Cases often become further complicated when patients experience refractory bleeding, which can be difficult to treat. This report describes an approach to rFXIII dosing in two patients who required deviation from standard protocols to maintain therapeutic FXIII troughs. We highlight limitations in our understanding of FXIII deficiency management, while also providing an example of the application of pharmacokinetic data to individualise therapy for improved outcomes. Finally, the case reminds us of the importance of patient-centered, cost-conscious care and multidisplinary teamwork in complex cases.


Assuntos
Deficiência do Fator XIII , Fator XIII , Deficiência do Fator XIII/diagnóstico , Deficiência do Fator XIII/tratamento farmacológico , Fator XIIIa , Humanos , Assistência Centrada no Paciente , Proteínas Recombinantes
6.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2786-2793, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34472296

RESUMO

To obtain chicken CD40L protein, the cDNA was prepared from chicken splenic cells and used as a template to clone and amplify CD40L by PCR. The target gene was cloned into pFastBac vector to construct a pFastBac-chCD40L donor plasmid. Recombinant plasmid was transformed into DH10Bac and recombinant Bacmid-chCD40L was obtained. The Bacmid-chCD40L plasmid was transfected into sf9 insect cells to obtain His-chCD40L protein. In addition, the target gene was cloned into pQM01 vector to construct a pQM01-chCD40L plasmid, recombinant plasmid was transfected into HEK 293T cells to obtain Strep-chCD40L protein. The chCD40L protein was purified by affinity chromatography, and the concentration of purified chCD40L protein was determined to be 0.01 mg/mL. Primary cells were isolated from the bursal tissue of 3-week old SPF chickens, and the chCD40L protein was added to the culture medium to stimulate cells. The chCD40L could bind to CD40 on B cells as examined by Western blotting, indirect immunofluorescence assay and flow cytometry, suggesting that chCD40L protein is biologically active. We successfully obtained chicken CD40L protein of biological activity, which laid the foundation in the in vitro culture of primary B lymphocytes for the isolation and diagnosis of virulent IBDV.


Assuntos
Baculoviridae , Galinhas , Animais , Baculoviridae/genética , Ligante de CD40/genética , Clonagem Molecular , Vetores Genéticos/genética , Proteínas Recombinantes/genética
7.
Int J Mol Sci ; 22(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34502086

RESUMO

In recent years, enzymes have risen as promising therapeutic tools for different pathologies, from metabolic deficiencies, such as fibrosis conditions, ocular pathologies or joint problems, to cancer or cardiovascular diseases. Treatments based on the catalytic activity of enzymes are able to convert a wide range of target molecules to restore the correct physiological metabolism. These treatments present several advantages compared to established therapeutic approaches thanks to their affinity and specificity properties. However, enzymes present some challenges, such as short in vivo half-life, lack of targeted action and, in particular, patient immune system reaction against the enzyme. For this reason, it is important to monitor serum immune response during treatment. This can be achieved by conventional techniques (ELISA) but also by new promising tools such as microarrays. These assays have gained popularity due to their high-throughput analysis capacity, their simplicity, and their potential to monitor the immune response of patients during enzyme therapies. In this growing field, research is still ongoing to solve current health problems such as COVID-19. Currently, promising therapeutic alternatives using the angiotensin-converting enzyme 2 (ACE2) are being studied to treat COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2/uso terapêutico , COVID-19/tratamento farmacológico , Terapia Enzimática/métodos , Proteínas Recombinantes/uso terapêutico , Enzima de Conversão de Angiotensina 2/farmacologia , Ensaios Clínicos Fase II como Assunto , Composição de Medicamentos/métodos , Estabilidade Enzimática , Terapia Enzimática/história , Terapia Enzimática/tendências , Meia-Vida , História do Século XX , História do Século XXI , Humanos , Proteínas Recombinantes/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Resultado do Tratamento , Internalização do Vírus/efeitos dos fármacos
8.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502139

RESUMO

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is the causative agent of the COVID19 pandemic. The SARS-CoV-2 genome encodes for a small accessory protein termed Orf9b, which targets the mitochondrial outer membrane protein TOM70 in infected cells. TOM70 is involved in a signaling cascade that ultimately leads to the induction of type I interferons (IFN-I). This cascade depends on the recruitment of Hsp90-bound proteins to the N-terminal domain of TOM70. Binding of Orf9b to TOM70 decreases the expression of IFN-I; however, the underlying mechanism remains elusive. We show that the binding of Orf9b to TOM70 inhibits the recruitment of Hsp90 and chaperone-associated proteins. We characterized the binding site of Orf9b within the C-terminal domain of TOM70 and found that a serine in position 53 of Orf9b and a glutamate in position 477 of TOM70 are crucial for the association of both proteins. A phosphomimetic variant Orf9bS53E showed drastically reduced binding to TOM70 and did not inhibit Hsp90 recruitment, suggesting that Orf9b-TOM70 complex formation is regulated by phosphorylation. Eventually, we identified the N-terminal TPR domain of TOM70 as a second binding site for Orf9b, which indicates a so far unobserved contribution of chaperones in the mitochondrial targeting of the viral protein.


Assuntos
COVID-19/transmissão , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , SARS-CoV-2/patogenicidade , Animais , Sítios de Ligação/genética , COVID-19/imunologia , COVID-19/virologia , Chlorocebus aethiops , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/isolamento & purificação , Humanos , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/isolamento & purificação , Mutação , Fosfoproteínas/genética , Fosfoproteínas/imunologia , Fosfoproteínas/isolamento & purificação , Fosfoproteínas/metabolismo , Fosforilação , Ligação Proteica/genética , Ligação Proteica/imunologia , Domínios Proteicos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Células Vero
9.
J Appl Oral Sci ; 29: e20201092, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34524369

RESUMO

OBJECTIVE: This study sought to compare the biocompatibility of a three-dimensional (3D)-printed titanium implant with a conventional machined titanium product, as well as the effect of such implant applied with recombinant human Bone Morphogenetic Protein Type 2 (rhBMP-2) for guided bone regeneration. METHODOLOGY: Disk-shaped titanium specimens fabricated either by the conventional machining technique or by the 3D-printing technique were compared by MC3T3-E1 cells cytotoxicity assay. New bone formation was evaluated using a rapid prototype titanium cap applied to the calvaria of 10 rabbits, which were divided into two groups: one including an atelopeptide collagen plug on one side of the cap (group I) and the other including a plug with rhBMP-2 on the other side (group II). At six and 12 weeks after euthanasia, rabbits calvaria underwent morphometric analysis through radiological and histological examination. RESULTS: Through the cytotoxicity assay, we identified a significantly higher number of MC3T3-E1 cells in the 3D-printed specimen when compared to the machined specimen after 48 hours of culture. Moreover, morphometric analysis indicated significantly greater bone formation at week 12 on the side where rhBMP-2 was applied when evaluating the upper portion immediately below the cap. CONCLUSION: The results suggest that 3D-printed titanium implant applied with rhBMP-2 enables new bone formation.


Assuntos
Osteogênese , Titânio , Animais , Proteína Morfogenética Óssea 2 , Regeneração Óssea , Impressão Tridimensional , Coelhos , Proteínas Recombinantes , Crânio/cirurgia , Fator de Crescimento Transformador beta
10.
Ann Palliat Med ; 10(7): 7841-7846, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34353071

RESUMO

BACKGROUND: Neutropenia is the most common adverse reaction seen in small cell lung cancer after chemotherapy. Febrile neutropenia (FN) leads to an increase in hospitalizations and may even be life-threatening. This paper aims to investigate the efficacy and adverse reactions of mecapegfilgrastim in the primary prophylaxis of neutropenia in patients with small cell lung cancer after receiving intermediate risk chemotherapy with at least one patient risk factor. METHODS: The clinical records of 106 patients with small cell lung cancer admitted to Zhejiang Cancer Hospital from June 2019 to January 2021 were retrospectively analyzed. Patients were divided into a mecapegfilgrastim [pegylated recombinant human granulocyte colony stimulating factor (PEG-rhG-CSF)] group and control group, each with 53 patients. The mecapegfilgrastim group received subcutaneous injection of mecapegfilgrastim 24 hours after the first cycle of chemotherapy, while the control group did not receive this. The Chi-square (χ2) test or Fisher exact test were used to compare the incidence of neutropenia, FN, and the proportion of patients administrated with full dose chemotherapy in the two groups after the first cycle of chemotherapy. Data on adverse events after mecapegfilgrastim were also collected. RESULTS: After the first cycle of chemotherapy, the incidence of neutropenia in the mecapegfilgrastim group was significantly lower than that in the control group (P=0.001) and the incidence of FN in the mecapegfilgrastim group was lower than that in the control group (P=0.118). The proportion of patients administrated with full-dose chemotherapy in the mecapegfilgrastim group was significantly higher than that in the control group (P=0.001). The main adverse reactions to mecapegfilgrastim were muscle pain, fever, and fatigue. CONCLUSIONS: After receiving intermediate risk chemotherapy, the incidence of neutropenia was significantly reduced by the primary prophylaxis of mecapegfilgrastim in patients with small cell lung cancer. The adverse events of mecapegfilgrastim were mild and tolerable, and included muscle pain, fever, and fatigue.


Assuntos
Neoplasias Pulmonares , Neutropenia , Carcinoma de Pequenas Células do Pulmão , Protocolos de Quimioterapia Combinada Antineoplásica , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neutropenia/induzido quimicamente , Neutropenia/prevenção & controle , Polietilenoglicóis , Proteínas Recombinantes , Estudos Retrospectivos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Resultado do Tratamento
11.
Nat Commun ; 12(1): 4713, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354054

RESUMO

Maize (Zea mays L.) is a cold-sensitive species that often faces chilling stress, which adversely affects growth and reproduction. However, the genetic basis of low-temperature adaptation in maize remains unclear. Here, we demonstrate that natural variation in the type-A Response Regulator 1 (ZmRR1) gene leads to differences in chilling tolerance among maize inbred lines. Association analysis reveals that InDel-35 of ZmRR1, encoding a protein harboring a mitogen-activated protein kinase (MPK) phosphorylation residue, is strongly associated with chilling tolerance. ZmMPK8, a negative regulator of chilling tolerance, interacts with and phosphorylates ZmRR1 at Ser15. The deletion of a 45-bp region of ZmRR1 harboring Ser15 inhibits its degradation via the 26 S proteasome pathway by preventing its phosphorylation by ZmMPK8. Transcriptome analysis indicates that ZmRR1 positively regulates the expression of ZmDREB1 and Cellulose synthase (CesA) genes to enhance chilling tolerance. Our findings thus provide a potential genetic resource for improving chilling tolerance in maize.


Assuntos
Zea mays/genética , Zea mays/fisiologia , Alelos , Temperatura Baixa , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Técnicas In Vitro , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Fosforilação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estresse Fisiológico/genética
12.
Nat Commun ; 12(1): 4710, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354070

RESUMO

Cyanophage S-2L is known to profoundly alter the biophysical properties of its DNA by replacing all adenines (A) with 2-aminoadenines (Z), which still pair with thymines but with a triple hydrogen bond. It was recently demonstrated that a homologue of adenylosuccinate synthetase (PurZ) and a dATP triphosphohydrolase (DatZ) are two important pieces of the metabolism of 2-aminoadenine, participating in the synthesis of ZTGC-DNA. Here, we determine that S-2L PurZ can use either dATP or ATP as a source of energy, thereby also depleting the pool of nucleotides in dATP. Furthermore, we identify a conserved gene (mazZ) located between purZ and datZ genes in S-2L and related phage genomes. We show that it encodes a (d)GTP-specific diphosphohydrolase, thereby providing the substrate of PurZ in the 2-aminoadenine synthesis pathway. High-resolution crystal structures of S-2L PurZ and MazZ with their respective substrates provide a rationale for their specificities. The Z-cluster made of these three genes - datZ, mazZ and purZ - was expressed in E. coli, resulting in a successful incorporation of 2-aminoadenine in the bacterial chromosomal and plasmidic DNA. This work opens the possibility to study synthetic organisms containing ZTGC-DNA.


Assuntos
DNA Bacteriano/genética , Genes Virais , Siphoviridae/genética , 2-Aminopurina/análogos & derivados , 2-Aminopurina/metabolismo , Adenilossuccinato Sintase/química , Adenilossuccinato Sintase/genética , Adenilossuccinato Sintase/metabolismo , Bacteriófagos , Pareamento de Bases , Cristalografia por Raios X , DNA Bacteriano/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Desoxiadenosinas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Genoma Viral , Redes e Vias Metabólicas , Modelos Moleculares , Monoéster Fosfórico Hidrolases/química , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Podoviridae/classificação , Podoviridae/genética , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Siphoviridae/classificação , Eletricidade Estática , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
13.
Nat Commun ; 12(1): 4709, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354080

RESUMO

Allostery represents a fundamental mechanism of biological regulation that involves long-range communication between distant protein sites. It also provides a powerful framework for novel therapeutics. NMDA receptors (NMDARs), glutamate-gated ionotropic receptors that play central roles in synapse maturation and plasticity, are prototypical allosteric machines harboring large extracellular N-terminal domains (NTDs) that provide allosteric control of key receptor properties with impact on cognition and behavior. It is commonly thought that GluN2A and GluN2B receptors, the two predominant NMDAR subtypes in the adult brain, share similar allosteric transitions. Here, combining functional and structural interrogation, we reveal that GluN2A and GluN2B receptors utilize different long-distance allosteric mechanisms involving distinct subunit-subunit interfaces and molecular rearrangements. NMDARs have thus evolved multiple levels of subunit-specific allosteric control over their transmembrane ion channel pore. Our results uncover an unsuspected diversity in NMDAR molecular mechanisms with important implications for receptor physiology and precision drug development.


Assuntos
Receptores de N-Metil-D-Aspartato/metabolismo , Regulação Alostérica , Animais , Feminino , Células HEK293 , Humanos , Técnicas In Vitro , Camundongos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Oócitos/metabolismo , Fotoquímica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Subunidades Proteicas , Ratos , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Xenopus laevis
15.
Nat Commun ; 12(1): 4718, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354069

RESUMO

Phospholipid synthesis and fat storage as triglycerides are regulated by lipin phosphatidic acid phosphatases (PAPs), whose enzymatic PAP function requires association with cellular membranes. Using hydrogen deuterium exchange mass spectrometry, we find mouse lipin 1 binds membranes through an N-terminal amphipathic helix, the Ig-like domain and HAD phosphatase catalytic core, and a middle lipin (M-Lip) domain that is conserved in mammalian and mammalian-like lipins. Crystal structures of the M-Lip domain reveal a previously unrecognized protein fold that dimerizes. The isolated M-Lip domain binds membranes both in vitro and in cells through conserved basic and hydrophobic residues. Deletion of the M-Lip domain in lipin 1 reduces PAP activity, membrane association, and oligomerization, alters subcellular localization, diminishes acceleration of adipocyte differentiation, but does not affect transcriptional co-activation. This establishes the M-Lip domain as a dimeric protein fold that binds membranes and is critical for full functionality of mammalian lipins.


Assuntos
Fosfatidato Fosfatase/química , Células 3T3-L1 , Adipogenia , Sequência de Aminoácidos , Animais , Membrana Celular/metabolismo , Sequência Conservada , Cristalografia por Raios X , Células HEK293 , Humanos , Espectrometria de Massa com Troca Hidrogênio-Deutério , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Modelos Moleculares , Simulação de Dinâmica Molecular , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/metabolismo , Ligação Proteica , Domínios Proteicos , Dobramento de Proteína , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Genética
16.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360993

RESUMO

The ferroxidase ceruloplasmin (CP) plays a crucial role in iron homeostasis in vertebrates together with the iron exporter ferroportin. Mutations in the CP gene give rise to aceruloplasminemia, a rare neurodegenerative disease for which no cure is available. Many aspects of the (patho)physiology of CP are still unclear and would benefit from the availability of recombinant protein for structural and functional studies. Furthermore, recombinant CP could be evaluated for enzyme replacement therapy for the treatment of aceruloplasminemia. We report the production and preliminary characterization of high-quality recombinant human CP in glycoengineered Pichia pastoris SuperMan5. A modified yeast strain lacking the endogenous ferroxidase has been generated and employed as host for heterologous expression of the secreted isoform of human CP. Highly pure biologically active protein has been obtained by an improved two-step purification procedure. Glycan analysis indicates that predominant glycoforms HexNAc2Hex8 and HexNAc2Hex11 are found at Asn119, Asn378, and Asn743, three of the canonical four N-glycosylation sites of human CP. The availability of high-quality recombinant human CP represents a significant advancement in the field of CP biology. However, productivity needs to be increased and further careful glycoengineering of the SM5 strain is mandatory in order to evaluate the possible therapeutic use of the recombinant protein for enzyme replacement therapy of aceruloplasminemia patients.


Assuntos
Ceruloplasmina/genética , Microbiologia Industrial/métodos , Engenharia de Proteínas/métodos , Saccharomycetales/genética , Ceruloplasmina/metabolismo , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomycetales/metabolismo
17.
Med Klin Intensivmed Notfmed ; 116(6): 491-498, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-34463792

RESUMO

BACKGROUND: Severe bleeding under antithrombotic therapy is common and challenging in intensive care medicine; on the one hand, rapid bleeding control must be achieved and, on the other hand, thromboembolic complications must be avoided. AIMS: The paper will provide a brief overview of direct oral anticoagulants, therapeutic options and precise instructions for dealing with severe bleeding. RESULTS: In addition to general measures in direct oral anticoagulant (DOAC)-associated major bleeding, prothrombin complex concentrate (PCC), idarucizumab and andexanet alfa are available as specific antidote therapy. In case of bleeding under heparin therapy, protamine sulfate is available as a possible antidote. CONCLUSIONS: In particular, the importance of andexanet alfa in the treatment of factor Xa inhibitor-associated bleeding requires further investigation.


Assuntos
Fibrinolíticos , Hemorragia , Administração Oral , Anticoagulantes/efeitos adversos , Antídotos/uso terapêutico , Inibidores do Fator Xa/efeitos adversos , Fibrinolíticos/efeitos adversos , Hemorragia/tratamento farmacológico , Hemorragia/terapia , Humanos , Proteínas Recombinantes/uso terapêutico
18.
J Biomed Nanotechnol ; 17(7): 1330-1338, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34446136

RESUMO

The best way in which to prepare scaffolds with good biological properties is an urgent problem in the field of tissue engineering. In this paper we discuss the preparation of nano-hydroxyapatite scaffold of recombinant human bone morphogenetic protein-2 (rhBMP-2) and its application in bone defect repair. rhBMP-2 reagent was dissolved in 1 mol/L sodium dihydrogen phosphate solution, and the rhBMP-2 solution was added to the nano-hydroxyapatite artificial bone with a 100 µL glass micro dropper at the rate of 10 drops/min to obtain Nano-HA/rhBMP-2 composite artificial bone. In in vivo experiments, rabbits were fixed on an operating table, a 2 cm longitudinal incision was made in the middle part of the radial forearm, and the radius was cut with a wire saw and periosteum, 2.5 cm away from the distal radius. After washing the wound with normal saline, Adv-hBMP-2/MC3T3-E1 nano-HA composite artificial bone, MC3T3-E1 nan-HA composite artificial bone, or Nano-HA artificial bone were implanted in different groups. The artificial bone scaffold prepared in this study has a stronger ability to repair bone defects than the alternatives, and is a promising prospect for the clinical treatment of bone defects.


Assuntos
Proteína Morfogenética Óssea 2 , Durapatita , Animais , Regeneração Óssea , Humanos , Osteogênese , Periósteo , Coelhos , Proteínas Recombinantes , Engenharia Tecidual , Tecidos Suporte , Fator de Crescimento Transformador beta
19.
PLoS One ; 16(8): e0255796, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34375345

RESUMO

Serological assays to detect antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) might contribute to confirming the suspected coronavirus disease 2019 (COVID-19) in patients not detected with molecular assays. Human antibodies that target the host angiotensin-converting enzyme 2-binding domain of the viral spike protein are a target for serodiagnosis and therapeutics. This study aimed to characterize the classes and subclasses of antibody responses to a recombinant receptor-binding protein (RBD) of SARS-CoV-2 in COVID-19 patients and investigated the reactivity of these antibodies in patients with other tropical infections and healthy individuals in Thailand. ELISAs for IgM, IgA, IgG and IgG subclasses based on RBD antigen were developed and tested with time series of 27 serum samples from 15 patients with COVID-19 and 60 samples from pre-COVID-19 outbreaks including acute dengue fever, murine typhus, influenza, leptospirosis and healthy individuals. Both RBD-specific IgA and IgG were detected in only 21% of the COVID-19 patients in the acute phase. The median IgA and IgG levels were significantly higher in the convalescent serum sample compared to the acute serum sample (P < 0.05). We observed the highest correlation between levels of IgG and IgA (rho = 0. 92). IgG1 and IgG3 were the major IgG subclasses detected in SARS-CoV-2 infection. Only acute IgG3 level was negatively associated with viral detection based on RT-PCR of ORF1ab gene (rho = -0.57). The median IgA and IgG levels in convalescence sera of COVID-19 patients were significantly higher than healthy individuals and convalescent sera of other febrile infectious patients. The analyses of antibody classes and subclasses provide insights into human immune responses against SARS-CoV-2 during natural infection and interpretation of antibody assays.


Assuntos
Anticorpos Antivirais/sangue , Formação de Anticorpos , COVID-19/patologia , Isotipos de Imunoglobulinas/sangue , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , COVID-19/sangue , COVID-19/virologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Domínios Proteicos/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Tailândia , Adulto Jovem
20.
PLoS One ; 16(8): e0253574, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34379620

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the ongoing coronavirus disease (COVID-19) pandemic which is characterized by respiratory illness and severe pneumonia, and currently accounts for > 2.5 million deaths worldwide. Recently, diverse mutations in the spike protein of SARS-CoV-2 were reported in United Kingdom (Alpha) and South Africa (Beta) strains which raise concerns over the potential increase in binding affinity towards the host cell receptor and diminished host neutralization capabilities. In order to study the effect of mutation in the binding efficiency of SARS-CoV-2 receptor binding domain (RBD) with anti-SARS-CoV/CoV-2 monoclonal antibodies (mAbs), we have produced SARS-CoV-2 RBD and two variants SARS-CoV-2 RBD (Alpha RBD and Beta RBD) in Nicotiana benthamiana by transient expression. Plant-produced SARS-CoV-2 RBD-Fc, Alpha RBD-Fc and Beta RBD-Fc exhibited specific binding to human angiotensin converting enzyme 2 (ACE2) receptor determined by ELISA. Intriguingly, the binding of plant-produced SARS-CoV-2 RBD proteins to plant-produced mAbs CR3022, B38, and H4 was found to be different depending on the variant mutation. In contrary to the plant-produced SARS-CoV-2 RBD-Fc and Alpha RBD-Fc, Beta RBD-Fc variant showed weak binding affinity towards the mAbs. The result suggested that the Beta RBD variant might have acquired partial resistance to neutralizing antibodies compared to other variants. However, further studies with sera from convalescent or vaccinated individuals are required to confirm this finding.


Assuntos
Anticorpos Monoclonais/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Tabaco/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Reações Antígeno-Anticorpo , COVID-19/patologia , COVID-19/virologia , Humanos , Ligação Proteica , Domínios Proteicos/imunologia , Proteínas Recombinantes/genética , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
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