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1.
Nat Commun ; 15(1): 4330, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773072

RESUMO

The Hendra and Nipah viruses (HNVs) are highly pathogenic pathogens without approved interventions for human use. In addition, the interaction pattern between the attachment (G) and fusion (F) glycoproteins required for virus entry remains unclear. Here, we isolate a panel of Macaca-derived G-specific antibodies that cross-neutralize HNVs via multiple mechanisms. The most potent antibody, 1E5, confers adequate protection against the Nipah virus challenge in female hamsters. Crystallography demonstrates that 1E5 has a highly similar binding pattern to the receptor. In cryo-electron microscopy studies, the tendency of 1E5 to bind to the upper or lower heads results in two distinct quaternary structures of G. Furthermore, we identify the extended outer loop ß1S2-ß1S3 of G and two pockets on the apical region of fusion (F) glycoprotein as the essential sites for G-F interactions. This work highlights promising drug candidates against HNVs and contributes deeper insights into the viruses.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Microscopia Crioeletrônica , Infecções por Henipavirus , Proteínas Virais de Fusão , Animais , Anticorpos Neutralizantes/imunologia , Feminino , Anticorpos Antivirais/imunologia , Infecções por Henipavirus/virologia , Infecções por Henipavirus/imunologia , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/química , Humanos , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/química , Vírus Nipah/imunologia , Internalização do Vírus/efeitos dos fármacos , Henipavirus/imunologia , Cricetinae , Reações Cruzadas/imunologia , Vírus Hendra/imunologia , Macaca , Mesocricetus , Cristalografia por Raios X
2.
Fitoterapia ; 175: 105957, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604260

RESUMO

Curcuma wenyujin (C. wenyujin) is a medicinal plant that is traditionally used to treat blood stagnation, liver fibrosis, pain, and jaundice. In this study, we examined the effect of C. wenyujin rhizome extract on hepatic lipid accumulation both in vivo and in vitro. We found that the petroleum ether fraction of C. wenyujin rhizome extract (CWP) considerably reduced the accumulation of lipids in HepG2 cells treated with oleic and palmitic acid. Ultra-high-performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry was used to analyze the main chemical constituents of CWP, and 21 sesquiterpenes were identified. In vivo experiments revealed that the administration of CWP significantly reduced the body weight and serum total cholesterol (TC) level of low-density-lipoprotein receptor knockout mice treated with a high-fat diet without affecting their food intake. CWP also significantly reduced the levels of liver TC, liver triglycerides, aspartate transaminase, and alanine transaminase. Histological examination revealed that CWP dose-dependently reduced steatosis in liver tissue, significantly downregulated the expression of lipogenesis genes, and increased the ß-oxidation of fatty acids. CWP also significantly increased autophagy-related proteins. In conclusion, CWP rich in sesquiterpenes reduces the accumulation of lipids in vivo and in vitro by improving lipid metabolism and activating autophagy.


Assuntos
Curcuma , Metabolismo dos Lipídeos , Camundongos Knockout , Extratos Vegetais , Rizoma , Sesquiterpenos , Curcuma/química , Rizoma/química , Animais , Humanos , Camundongos , Células Hep G2 , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Colesterol/sangue , Colesterol/metabolismo , Dieta Hiperlipídica , Receptores de LDL/metabolismo , Receptores de LDL/genética , Estrutura Molecular
3.
Int Wound J ; 21(4): e14827, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522433

RESUMO

Diabetic Foot Ulcers (DFUs) are a major complication of diabetes, often leading to amputation. Understanding the relationship between haematological inflammatory markers and the incidence of amputation in DFU patients with infectious complications is crucial for improving management and outcomes. This retrospective study, conducted from May 2020 to October 2022, involved 109 patients with DFUs, categorised into amputation (AM) and non-amputation (NAM) groups. Patients were evaluated for various factors, including demographic data, DFU duration, and blood parameters such as haemoglobin A1c (HbA1c), haemoglobin (Hb), albumin (ALB), white blood cell count (WBC), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), C-reactive protein (CRP), platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), and lymphocyte-to-monocyte ratio (LMR). Statistical analyses were performed using independent sample t-tests, Mann-Whitney U test and logistic regression. The univariate analysis showed no significant difference in BMI, DM duration or DFU duration between groups. However, significant differences were noted in PCT, Hb, ESR, ALB, HbA1c and WBC levels, and in inflammatory ratios (NLR, PLR and LMR). Multivariate logistic regression identified CRP, NLR and PLR as independent risk factors for amputation. The study highlights CRP, PLR and NLR as key independent risk factors for amputation in patients with DFUs. These easily obtainable markers from routine blood tests can effectively aid in predicting the risk of osteomyelitis and amputation, enhancing clinical decision making and patient care strategies.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/cirurgia , Estudos Retrospectivos , Hemoglobinas Glicadas , Biomarcadores , Neutrófilos , Proteína C-Reativa , Amputação Cirúrgica
4.
Int Wound J ; 21(3): e14502, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973551

RESUMO

Diabetic foot ulcers (DFUs) pose significant clinical challenges, representing severe complications in diabetes mellitus patients and contributing to non-traumatic amputations. Identifying reliable biomarkers can optimize early diagnosis and improve therapeutic outcomes. This study focused on evaluating the association between serum levels of 25-hydroxyvitamin D [25-(OH)D], Serum Retinol Binding Protein (RBP), and Cyclooxygenase-2 (COX-2) in elderly DFU patients. A retrospective study involving 240 participants, from March 2020 to March 2023. The participants were segmented into three cohorts: 80 with DFUs, 80 diabetic patients without DFUs, and 80 healthy controls. Serum concentrations of the three biomarkers were assayed using methods like enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay, and an automated biochemistry analyser. Comparisons were made both between groups and within the DFU group based on disease severity. Statistical analysis revealed significant differences in biomarker levels across the groups (p < 0.05). COX-2 and RBP concentrations were highest in the DFU group, followed by the non-DFU diabetic group, and lowest in the control group. Conversely, 25(OH)D levels were highest in the control group, followed by the non-DFU diabetic group, and lowest in the DFU group. Within the DFU group, RBP and COX-2 levels increased with disease severity, while 25(OH)D levels decreased. These variations were especially pronounced in patients with the most severe Wagner grading. A significant positive correlation was observed between disease severity and levels of RBP (r = 0.651, p < 0.05) and COX-2 (r = 0.356, p < 0.05). Conversely, a significant negative correlation was identified between disease severity and 25(OH)D levels (r = -0.658, p < 0.05). Assessing 25(OH)D, RBP, and COX-2 serum levels offers a promising tool for evaluating the severity and progression of DFUs. Monitoring these biomarkers can enrich our understanding of the metabolic and inflammatory pathways of the disease and potentially refine therapeutic strategies.

5.
Front Immunol ; 14: 1239179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868993

RESUMO

Introduction: The SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant and exhibits immune escape to current COVID-19 vaccines, the further boosting strategies are required. Methods: We have conducted a non-randomized, open-label and parallel-controlled phase 4 trial to evaluate the magnitude and longevity of immune responses to booster vaccination with intramuscular adenovirus vectored vaccine (Ad5-nCoV), aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines. Results: The aerosolized Ad5-nCoV induced the most robust and long-lasting neutralizing activity against Omicron variant and IFNg T-cell response among all the boosters, with a distinct mucosal immune response. SARS-CoV-2-specific mucosal IgA response was substantially generated in subjects boosted with the aerosolized Ad5-nCoV at day 14 post-vaccination. At month 6, participants boosted with the aerosolized Ad5-nCoV had remarkably higher median titer and seroconversion of the Omicron BA.4/5-specific neutralizing antibody than those who received other boosters. Discussion: Our findings suggest that aerosolized Ad5-nCoV may provide an efficient alternative in response to the spread of the Omicron BA.4/5 variant. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=152729, identifier ChiCTR2200057278.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Imunidade nas Mucosas , Anticorpos
6.
Cell Discov ; 9(1): 37, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37015915

RESUMO

The pandemic of COVID-19 caused by SARS-CoV-2 continues to spread around the world. Mutant strains of SARS-CoV-2 are constantly emerging. At present, Omicron variants have become mainstream. In this work, we carried out a systematic and comprehensive analysis of the reported spike protein antibodies, counting the epitopes and genotypes of these antibodies. We further comprehensively analyzed the impact of Omicron mutations on antibody epitopes and classified these antibodies according to their binding patterns. We found that the epitopes of the H-RBD class antibodies were significantly less affected by Omicron mutations than other classes. Binding and virus neutralization experiments showed that such antibodies could effectively inhibit the immune escape of Omicron. Cryo-EM results showed that this class of antibodies utilized a conserved mechanism to neutralize SARS-CoV-2. Our results greatly help us deeply understand the impact of Omicron mutations. Meanwhile, it also provides guidance and insights for developing Omicron antibodies and vaccines.

7.
Front Cell Dev Biol ; 10: 900637, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990602

RESUMO

Objective: Acanthopanax senticosus (Rupr. et Maxim.) Harms (ASH) is a traditional herbal medicine widely known for its antifatigue and antistress effects, as well as tonifying qi, invigorating spleen and kidney, and tranquilizing the mind. Recent evidence suggests that ASH has a therapeutic effect on major depressive disorder (MDD), but its mechanism is still unclear. The current study aimed to investigate the effect of ASH on MDD and potential therapeutic mechanisms. Materials and Methods: The chemical compound potential target network was predicted based on network pharmacology. Simultaneously, chronic unpredictable mild stress (CUMS) model mice were orally administrated ASH with three dosages (400, 200, and 100 mg/kg) for 6 weeks, and hepatic metabolomics based on gas chromatography-mass spectrometry (GC-MS) was carried out to identify differential metabolites and related metabolic pathways. Next, the integrated analysis of metabolomics and network pharmacology was applied to find the key target. Finally, molecular docking technology was employed to define the combination of the key target and the corresponding compounds. Results: A total of 13 metabolites and four related metabolic pathways were found in metabolomics analysis. From the combined analysis of network pharmacology and metabolomics, six targets (DAO, MAOA, MAOB, GAA, HK1, and PYGM) are the overlapping targets and two metabolic pathways (glycine, serine, and threonine metabolism and starch and sucrose metabolism) are the most related pathways. Finally, DAO, MAOA, MAOB, GAA, HK1, and PYGM were verified bounding well to their corresponding compounds including isofraxidin, eleutheroside B1, eleutheroside C, quercetin, kaempferol, and acacetin. Conclusion: Based on these results, it was implied that the potential mechanism of ASH on MDD was related to the regulation of metabolism of several excitatory amino acids and carbohydrates, as well as the expression of DAO, MAOA, MAOB, GAA, HK1, and PYGM.

8.
Signal Transduct Target Ther ; 7(1): 257, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906201

RESUMO

Highly divergent SARS-CoV-2 variants have continuously emerged and spread around the world, and updated vaccines and innovative vaccination strategies are urgently needed to address the global SARS-COV2 pandemic. Here, we established a series of Ad5-vectored SARS-CoV-2 variant vaccines encoding multiple spike proteins derived from the Alpha, Beta, Gamma, Epsilon, Kappa, Delta and Omicron lineages and analyzed the antibody immune responses induced by single-dose and prime-boost vaccination strategies against emerging SARS-CoV-2 variants of concern (VOCs). Single-dose vaccination with SARS-CoV-2 variant vaccines tended to elicit the optimal self-matched neutralizing effects, and Ad5-B.1.351 produced more broad-spectrum cross-neutralizing antibodies against diverse variants. In contrast, prime-boost vaccination further strengthened and broadened the neutralizing antibody responses against highly divergent SARS-CoV-2 variants. The heterologous administration of Ad5-B.1.617.2 and Ad5-B.1.429 to Ad5-WT-primed mice resulted in superior antibody responses against most VOCs. In particular, the Omicron spike could only stimulate self-matched neutralizing antibodies with infrequent cross-reactivities to other variants used in single-dose vaccination strategies; moreover, with prime-boost regimens, this vaccine elicited an optimal specific neutralizing antibody response to Omicron, and prompted cross-antibody responses against other VOCs that were very similar to those obtained with Ad5-WT booster. Overall, this study delineated the unique characteristics of antibody responses to the SARS-CoV-2 VOC spikes with the single-dose or prime-boost vaccination strategies and provided insight into the vaccine development of next SARS-CoV-2 VOCs.


Assuntos
COVID-19 , Vacinas Virais , Animais , Anticorpos Neutralizantes/genética , Anticorpos Antivirais , Formação de Anticorpos , Vacinas contra COVID-19 , Humanos , Camundongos , RNA Viral , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética
9.
Viruses ; 14(6)2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35746803

RESUMO

The global spread of SARS-CoV-2 and its variants poses a serious threat to human health worldwide. Recently, the emergence of Omicron has presented a new challenge to the prevention and control of the COVID-19 pandemic. A convenient and reliable in vitro neutralization assay is an important method for validating the efficiency of antibodies, vaccines, and other potential drugs. Here, we established an effective assay based on a pseudovirus carrying a full-length spike (S) protein of SARS-CoV-2 variants in the HIV-1 backbone, with a luciferase reporter gene inserted into the non-replicate pseudovirus genome. The key parameters for packaging the pseudovirus were optimized, including the ratio of the S protein expression plasmids to the HIV backbone plasmids and the collection time for the Alpha, Beta, Gamma, Kappa, and Omicron pseudovirus particles. The pseudovirus neutralization assay was validated using several approved or developed monoclonal antibodies, underscoring that Omicron can escape some neutralizing antibodies, such as REGN10987 and REGN10933, while S309 and ADG-2 still function with reduced neutralization capability. The neutralizing capacity of convalescent plasma from COVID-19 convalescent patients in Wuhan was tested against these pseudoviruses, revealing the immune evasion of Omicron. Our work established a practical pseudovirus-based neutralization assay for SARS-CoV-2 variants, which can be conducted safely under biosafety level-2 (BSL-2) conditions, and this assay will be a promising tool for studying and characterizing vaccines and therapeutic candidates against Omicron-included SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/terapia , Humanos , Imunização Passiva , Testes de Neutralização/métodos , Pandemias , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Soroterapia para COVID-19
10.
Signal Transduct Target Ther ; 7(1): 139, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35478188

RESUMO

The SARS-CoV-2 Omicron variant shows substantial resistance to neutralization by infection- and vaccination-induced antibodies, highlighting the demands for research on the continuing discovery of broadly neutralizing antibodies (bnAbs). Here, we developed a panel of bnAbs against Omicron and other variants of concern (VOCs) elicited by vaccination of adenovirus-vectored COVID-19 vaccine (Ad5-nCoV). We also investigated the human longitudinal antibody responses following vaccination and demonstrated how the bnAbs evolved over time. A monoclonal antibody (mAb), named ZWD12, exhibited potent and broad neutralization against SARS-CoV-2 variants Alpha, Beta, Gamma, Kappa, Delta, and Omicron by blocking the spike protein binding to the angiotensin-converting enzyme 2 (ACE2) and provided complete protection in the challenged prophylactic and therapeutic K18-hACE2 transgenic mouse model. We defined the ZWD12 epitope by determining its structure in complex with the spike (S) protein via cryo-electron microscopy. This study affords the potential to develop broadly therapeutic mAb drugs and suggests that the RBD epitope bound by ZWD12 is a rational target for the design of a broad spectrum of vaccines.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais/genética , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , Vacinas contra COVID-19/genética , Microscopia Crioeletrônica , Epitopos , Humanos , Camundongos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinação , Proteínas do Envelope Viral
11.
Int J Anal Chem ; 2021: 5524361, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567122

RESUMO

OBJECTIVE: To develop a new method for quantitatively analyzing six tyrosine kinase inhibitors (gefitinib, erlotinib, icotinib, afatinib, osimertinib, and crizotinib) used in the treatment of non-small cell lung cancer (NSCLC) by liquid chromatography-tandem mass spectrometry (LC-MS/MS). METHODS: The analytes were detected in the selected reaction monitoring mode on a triple quadrupole mass spectrometer with the positive ionization mode. Carbamazepine was utilized as the internal standard. The pretreatment of the plasma sample was completed based on protein precipitation with acetonitrile, and the analytes were separated on an Agilent Zorbax SB-C18 reversed-phase column (2.1 mm × 100 mm, 3.5 µm, Agilent, USA) using gradient elution. The mobile phase consisted of 0.1% formic acid in water (phase A) and 0.1% formic acid in acetonitrile (phase B). The flow rate was 0.3 mL/min, and the injection volume was 5 µL. The column temperature was set and maintained at 35°C. RESULTS: The calibration curves were linear over the range from 5.0 to 1000.0 ng/mL for gefitinib, crizotinib, and osimertinib; from 50.0 to 4000.0 ng/mL for icotinib and erlotinib; and from 5.0 to 400.0 ng/mL for afatinib. Linear correlation coefficients were >0.990 for all regression curves. The intra- and interday accuracy and precision of the method were within ±15.0% and not more than 15.0%, respectively. The mean recovery of all the analytes ranged from 70.18% to 110.76%, the matrix effect was from 88.85% to 127.58%, and stability was within ±15.0%. CONCLUSION: This newly developed method was sensitive, simple, and robust and could be used in therapeutic drug monitoring of six tyrosine kinase inhibitors in NSCLC patients.

12.
Int Immunopharmacol ; 91: 107297, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360088

RESUMO

Clostridium tetani causes life-threatening disease by producing tetanus neurotoxin (TeNT), one of the most toxic protein substances. Toxicosis can be prevented and cured by administration of anti-TeNT neutralizing antibodies. Here, we identified a series of monoclonal antibodies (mAbs) derived from memory B cells of a healthy adult immunized with the C-terminal domain of TeNT (TeNT-Hc). Thirteen mAbs bound to both tetanus toxoid (TT) and TeNT-Hc, while two mAbs recognized only TT. VH3-23 was the most frequently used germline gene in these TT-binding mAbs, and the pairwise identity values of the VH gene sequences ranged from 27% to 69%. Three of these mAbs-T3, T7, and T9-6-completely protected mice from challenge with 2× LD50 of TeNT, and two (T2 and T18) significantly prolonged the survival time. The five neutralizing mAbs recognized distinct epitopes on TT, with binding affinities ranging from 0.123 to 11.9 nM. Our study provides promising therapeutic candidates for tetanus.


Assuntos
Anticorpos Antibacterianos/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Clostridium tetani/imunologia , Vacina contra Difteria e Tétano/administração & dosagem , Vacinas contra Difteria, Tétano e Coqueluche Acelular/administração & dosagem , Imunogenicidade da Vacina , Toxoide Tetânico/administração & dosagem , Tétano/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Monoclonais/sangue , Anticorpos Neutralizantes/sangue , Especificidade de Anticorpos , Clostridium tetani/patogenicidade , Modelos Animais de Doenças , Epitopos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Tétano/imunologia , Tétano/microbiologia , Fatores de Tempo , Vacinação
13.
Science ; 369(6504): 650-655, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571838

RESUMO

Developing therapeutics against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be guided by the distribution of epitopes, not only on the receptor binding domain (RBD) of the Spike (S) protein but also across the full Spike (S) protein. We isolated and characterized monoclonal antibodies (mAbs) from 10 convalescent COVID-19 patients. Three mAbs showed neutralizing activities against authentic SARS-CoV-2. One mAb, named 4A8, exhibits high neutralization potency against both authentic and pseudotyped SARS-CoV-2 but does not bind the RBD. We defined the epitope of 4A8 as the N-terminal domain (NTD) of the S protein by determining with cryo-eletron microscopy its structure in complex with the S protein to an overall resolution of 3.1 angstroms and local resolution of 3.3 angstroms for the 4A8-NTD interface. This points to the NTD as a promising target for therapeutic mAbs against COVID-19.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Anticorpos Antivirais/metabolismo , Afinidade de Anticorpos , Especificidade de Anticorpos , Antígenos Virais/imunologia , Linfócitos B/imunologia , COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/terapia , Proteínas do Nucleocapsídeo de Coronavírus , Microscopia Crioeletrônica , Ensaio de Imunoadsorção Enzimática , Genes de Cadeia Pesada de Imunoglobulina , Humanos , Memória Imunológica , Pessoa de Meia-Idade , Mutação , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Fosfoproteínas , Pneumonia Viral/terapia , Domínios Proteicos , Domínios e Motivos de Interação entre Proteínas/imunologia , Receptores de Coronavírus , Receptores Virais/metabolismo , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero , Adulto Jovem
14.
Viruses ; 12(3)2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120864

RESUMO

The Rift Valley fever virus (RVFV) is an arthropod-borne virus that can not only cause severe disease in domestic animals but also in humans. However, the licensed vaccines or available therapeutics for humans do not exist. Here, we report two Gn-specific neutralizing antibodies (NAbs), isolated from a rhesus monkey immunized with recombinant human adenoviruses type 4 expressing Rift Valley fever virus Gn and Gc protein (rHAdV4-GnGcopt). The two NAbs were both able to protect host cells from RVFV infection. The interactions between NAbs and Gn were then characterized to demonstrate that these two NAbs might preclude RVFV glycoprotein rearrangement, hindering the exposure of fusion loops in Gc to endosomal membranes after the virus invades the host cell. The target region for the two NAbs is located in the Gn domain III, implying that Gn is a desired target for developing vaccines and neutralizing antibodies against RVFV.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Epitopos , Humanos , Imunização , Macaca mulatta , Modelos Moleculares , Conformação Molecular , Testes de Neutralização , Ligação Proteica , Febre do Vale de Rift/virologia , Relação Estrutura-Atividade , Proteínas do Envelope Viral/química
15.
MAbs ; 12(1): 1742457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32213108

RESUMO

Ebola virus (EBOV) can cause severe hemorrhagic fever in humans, and no approved treatment is currently available. Although several antibodies have achieved good protection in animal models, the potential emerging isolates of ebolavirus and the unknown effects of experimental antibodies in humans underscore the need to develop additional antibodies to address the threat of Ebola. Here, we isolated a series of memory B cell-derived monoclonal antibodies from healthy Chinese adults vaccinated with Ad5-EBOV. These antibodies were encoded by diverse germline genes and had high levels of somatic hypermutation. Most antibodies were cross-reactive and could bind at least two ebolavirus glycoproteins (GPs). Seven neutralizing antibodies were identified using HIV-EBOV GP-Luc pseudovirus, and they effectively neutralized authentic EBOV. In particular, monoclonal antibody 2G1 exhibited potent cross-neutralization against HIV-EBOV/SUDV/BDBV GP-Luc bearing different ebolavirus GPs. We used truncated GPs, competition assays, and software prediction to analyze seven neutralizing antibodies, which bound four different epitopes on GP. Importantly, three of these antibodies provided complete protection in mice when administered one day post-infection. Our study expands the list of candidate antibodies and the options for successfully treating ebolavirus infection.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Animais , Feminino , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Masculino , Camundongos
16.
Sheng Wu Gong Cheng Xue Bao ; 34(6): 993-1001, 2018 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-29943545

RESUMO

Given the increasing exploitation of antibodies in different contexts such as molecular diagnostics and therapeutics, it would be beneficial to unravel properties of antigen-antibody interaction with modeling of computational protein-protein docking, especially, in the absence of a cocrystal structure. However, obtaining a native-like antigen-antibody structure remains challenging due in part to failing to reliably discriminate accurate from inaccurate structures among tens of thousands of decoys after computational docking with existing scoring function. We hypothesized that some important physicochemical and energetic features could be used to describe antigen-antibody interfaces and identify native-like antigen-antibody structure. We prepared a dataset, a subset of Protein-Protein Docking Benchmark Version 4.0, comprising 37 nonredundant 3D structures of antigen-antibody complexes, and used it to train and test multivariate logistic regression equation which took several important physicochemical and energetic features of decoys as dependent variables. Our results indicate that the ability to identify native-like structures of our method is superior to ZRANK and ZDOCK score for the subset of antigen-antibody complexes. And then, we use our method in workflow of predicting epitope of anti-Ebola glycoprotein monoclonal antibody-4G7 and identify three accurate residues in its epitope.


Assuntos
Anticorpos/química , Antígenos/química , Mapeamento de Interação de Proteínas , Análise de Regressão , Algoritmos , Epitopos , Humanos , Ligação Proteica , Conformação Proteica
17.
Mol Med Rep ; 18(1): 391-398, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29749520

RESUMO

Upregulated gene 11 (URG11) represents a gene upregulated by hepatitis B virus X protein and is involved in the biological processes of multifarious tumors. The present study aimed to investigate the protective effects and regulatory mechanisms of URG11 in benign prostatic hyperplasia (BPH). URG11, Ras homolog family member A (RhoA) and Rho­associated protein kinase 1 (ROCK1) expression was detected in patients with BPH using reverse transcription­quantitative polymerase chain reaction (RT­qPCR). Furthermore, URG11 expression was silenced using URG11­targeting small interfering RNAs. In addition, cell viability was determined by performing a Cell Counting Kit­8 assay, and the effect of URG11 on the cell cycle was investigated by flow cytometry. Expression levels of cyclin D1, p27, E­cadherin, N­cadherin, vimentin, RhoA and ROCK1 were investigated by RT­qPCR and western blotting. The results revealed that the expression levels of URG11, RhoA and ROCK1 were enhanced in patients with BPH­1 cells compared with matched healthy controls. Furthermore, it was demonstrated that transforming growth factor­ß (TGF­ß) induced the proliferation of BPH­1 cells in vitro, and silencing of URG11 inhibited the effects of TGF­ß on BPH­1 cell proliferation and the cell cycle. In addition, silencing of URG11 altered the expression levels of cell cycle­associated genes, epithelial­mesenchymal transition­associated genes, and RhoA and ROCK1 protein levels. Thus, the results of the present study suggest that URG11 may be a potential therapeutic target, which may be important to inhibit the development and progression of prostatic hyperplasia.


Assuntos
Proliferação de Células , Transição Epitelial-Mesenquimal , Inativação Gênica , Hiperplasia Prostática/metabolismo , Transdução de Sinais , Transativadores/biossíntese , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Adulto , Idoso , Linhagem Celular , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Quinases Associadas a rho/genética , Proteína rhoA de Ligação ao GTP/genética
18.
Biomarkers ; 23(5): 435-445, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29465000

RESUMO

CONTEXT: Prostate cancer (PCa) is one of the most commonly diagnosed malignancy in men in the western world. OBJECTIVE: We aim to investigate the biological role of long non-coding RNA FENDRR and its mechanism in PCa. MATERIALS AND METHODS: We determined the expression of FENDRR and miR-18a-5p in PCa tissues and examined the regulatory mechanism in PCa cell lines. RESULTS: FENDRR transcripts in human PCa tissues were significantly decreased compared with the normal controls. Reduced expression of FENDRR was correlated with the increase of pathological degree and poor prognosis in PCa patients. Upregulation of FENDRR inhibited cell proliferation, increased apoptosis and decreased invasion and migration ability, which was inhibited by miR-18a-5p mimic. Knockdown of FENDRR resulted in a significant increase of PCa cell proliferation and decrease of apoptosis and this effect was inhibited miR-18a-5p inhibitor. FENDRR and RUNX1 contain potential target sites for miR-18a-5p. miR-18a-5p mimic inhibited RUNX1 expression and luciferase activity. FENDRR could increase RUNX1 expression, which was inhibited by miR-18a-5p. The effect of FENDRR on cell proliferation, apoptosis and invasion and migration ability was suppressed by silence of RUNX1. DISCUSSION AND CONCLUSION: These results position FENDRR/miR-18a-5p/RUNX1 as a potential therapeutic target and biomarker for PCa.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/tratamento farmacológico , RNA Longo não Codificante/farmacologia , Apoptose/efeitos dos fármacos , Ligação Competitiva/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino
19.
Int J Mol Med ; 41(5): 2784-2792, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29484381

RESUMO

Diabetic nephropathy (DN) is the leading cause of end-stage failure of the kidney, but the efficacy of current strategies available for the prevention of DN remains unsatisfactory. The purpose of this study was to assess whether sitagliptin (SIT) has therapeutic potential for prevention of DN and to investigate its possible mechanism. The effects of SIT on DN were investigated in rats with type 2 diabetes mellitus (T2DM) and rat mesangial cells (MCs) induced by high glucose. T2DM rats were administered at a dose of 10 mg/kg SIT. The kidney index, 24 h urinary protein, blood urea nitrogen (BUN), serum creatinine (Cr), accumulation of glycogen and collagens were investigated by different methods. MCs were administered with SIT at doses of 0.1, 1 and 10 µmol/ml. The possible mechanism of SIT on protection of diabetic kidney injury was examined by expression of transforming growth factor-ß1 (TGF-ß1)/Smad pathway. The results showed that the SIT-treated diabetic rats significantly reduced diabetic kidney injury by inhibiting the kidney index and attenuating 24 h urinary protein, reducing BUN and serum creatinine, inhibiting progressive renal fibrosis and increassing extracellular matrix including collagen IV and fibronectin. Further studies showed that inhibition of renal fibrosis in SIT-treated diabetic rats and MCs were associated with rebalancing of TGF-ß1/Smad pathway. Sitagliptin may be a potent agent for preventing the progression of DN through inhabiting TGF-ß1/Smad-mediated renal fibrosis.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Rim/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fosfato de Sitagliptina/uso terapêutico , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Fibrose , Hipoglicemiantes/farmacologia , Rim/metabolismo , Rim/patologia , Masculino , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Células Mesangiais/patologia , Ratos , Ratos Sprague-Dawley , Fosfato de Sitagliptina/farmacologia
20.
Exp Ther Med ; 14(4): 3862-3867, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29042993

RESUMO

Diabetic nephropathy (DN) is one of the most important causes that leads to end-stage renal disease and the efficacy of strategies currently available for the prevention of DN remains unsatisfactory. Sitagliptin (SIT), which is a dipeptidyl peptidase-4 inhibitor, exhibited a modest beneficial effect on glycated hemoglobin levels and is capable of ameliorating renal ischemia reperfusion injury. By determining the expression of transforming growth factor-ß1 (TGF-ß1), connective tissue growth factor (CTGF), collagen type IV (ColIV) and fibronectin (FN) levels in high glucose-cultured glomerular mesangial cells (MCs), the present study aimed to assess the anti-proliferative and anti-fibrotic effects of SIT on the therapeutic potential for the prevention of DN and its mechanism. Specifically, cell proliferation was determined via cell counting kit-8 assay, and the expression levels of TGF-ß1 and CTGF mRNA were detected by reverse transcription polymerase chain reaction analysis. Furthermore, the secretion of TGF-ß1, CTGF, ColIV and FN proteins was measured via enzyme-linked immunosorbent assays. The results demonstrated that high glucose induced the proliferation of MCs and enhanced the expression of TGF-ß1, CTGF, ColIV and FN. Furthermore, treatment with SIT inhibited cell proliferation and the expression of TGF-ß1, CTGF, ColIV and FN induced by high glucose. In conclusion, SIT inhibits cell proliferation and the expression of the major extracellular matrix proteins induced by high glucose, indicating its value for treating or relieving DN.

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