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2.
Signal Transduct Target Ther ; 9(1): 98, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609366

RESUMO

Evidence suggests associations between COVID-19 patients or vaccines and glycometabolic dysfunction and an even higher risk of the occurrence of diabetes. Herein, we retrospectively analyzed pancreatic lesions in autopsy tissues from 67 SARS-CoV-2 infected non-human primates (NHPs) models and 121 vaccinated and infected NHPs from 2020 to 2023 and COVID-19 patients. Multi-label immunofluorescence revealed direct infection of both exocrine and endocrine pancreatic cells by the virus in NHPs and humans. Minor and limited phenotypic and histopathological changes were observed in adult models. Systemic proteomics and metabolomics results indicated metabolic disorders, mainly enriched in insulin resistance pathways, in infected adult NHPs, along with elevated fasting C-peptide and C-peptide/glucose ratio levels. Furthermore, in elder COVID-19 NHPs, SARS-CoV-2 infection causes loss of beta (ß) cells and lower expressed-insulin in situ characterized by islet amyloidosis and necrosis, activation of α-SMA and aggravated fibrosis consisting of lower collagen in serum, an increase of pancreatic inflammation and stress markers, ICAM-1 and G3BP1, along with more severe glycometabolic dysfunction. In contrast, vaccination maintained glucose homeostasis by activating insulin receptor α and insulin receptor ß. Overall, the cumulative risk of diabetes post-COVID-19 is closely tied to age, suggesting more attention should be paid to blood sugar management in elderly COVID-19 patients.


Assuntos
COVID-19 , Diabetes Mellitus , Adulto , Animais , Humanos , Idoso , SARS-CoV-2 , Receptor de Insulina , Peptídeo C , DNA Helicases , Estudos Retrospectivos , Proteínas de Ligação a Poli-ADP-Ribose , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , Glucose
3.
Case Rep Dermatol ; 16(1): 63-69, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440721

RESUMO

Introduction: Pachydermoperiostosis (PDP), or primary hypertrophic osteoarthropathy, is a rare autosomal dominant disease with primary clinical features of pachydermia (thickening of skin) and periostosis (new bone formation). Keloid scar formation is also rather obscure, and some scientists have claimed that keloid scars contain an excessive amount of fibroblasts compared with normal skin as well as a dense mass of irregularly deposited connective tissues. Case Presentation: A 25-year-old man exhibited extensive skin folding on his face, a gyrus-like scalp, depressed nasolabial folds, and keloids. Symptoms began at 18 years of age, progressing insidiously. Additionally, he experienced clubbing of fingers and toes, joint pain, muscle soreness, and hyperhidrosis. Radiographic examinations revealed thickened bone and cystic regions. Diagnosed with complete primary PDP and facial keloid scars, he underwent skin dermabrasion, biopsies, and a comprehensive treatment involving, botulinum toxin injections, 5-fluorouracil, and a carbon dioxide lattice laser. Conclusion: PDP presents challenges due to its unclear etiology but stabilizes over time in most cases. Comprehensive treatment strategies, including dermabrasion and a combination of intralesional therapies, are effective in managing keloids in PDP patients. This case contributes to the understanding of managing rare diseases and underscores the importance of personalized approaches to improve therapeutic outcomes in patients with complete primary PDP and concurrent keloids.

4.
Proc Natl Acad Sci U S A ; 121(3): e2315354120, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38194459

RESUMO

The emergence of Omicron lineages and descendent subvariants continues to present a severe threat to the effectiveness of vaccines and therapeutic antibodies. We have previously suggested that an insufficient mucosal immunoglobulin A (IgA) response induced by the mRNA vaccines is associated with a surge in breakthrough infections. Here, we further show that the intramuscular mRNA and/or inactivated vaccines cannot sufficiently boost the mucosal secretory IgA response in uninfected individuals, particularly against the Omicron variant. We thus engineered and characterized recombinant monomeric, dimeric, and secretory IgA1 antibodies derived from four neutralizing IgG monoclonal antibodies (mAbs 01A05, rmAb23, DXP-604, and XG014) targeting the receptor-binding domain of the spike protein. Compared to their parental IgG antibodies, dimeric and secretory IgA1 antibodies showed a higher neutralizing activity against different variants of concern (VOCs), in part due to an increased avidity. Importantly, the dimeric or secretory IgA1 form of the DXP-604 antibody significantly outperformed its parental IgG antibody, and neutralized the Omicron lineages BA.1, BA.2, and BA.4/5 with a 25- to 75-fold increase in potency. In human angiotensin converting enzyme 2 (ACE2) transgenic mice, a single intranasal dose of the dimeric IgA DXP-604 conferred prophylactic and therapeutic protection against Omicron BA.5. Thus, dimeric or secretory IgA delivered by nasal administration may potentially be exploited for the treatment and prevention of Omicron infection, thereby providing an alternative tool for combating immune evasion by the current circulating subvariants and, potentially, future VOCs.


Assuntos
Anticorpos Monoclonais , Imunoglobulina A Secretora , Animais , Camundongos , Humanos , Imunoglobulina G , Imunoglobulina A , Administração Intranasal , Camundongos Transgênicos
5.
Emerg Microbes Infect ; 12(1): e2192816, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36939609

RESUMO

Emerging zoonoses of wildlife origin caused by previously unknown agents are one of the most important challenges for human health. The Qinghai-Tibet Plateau represents a unique ecological niche with diverse wildlife that harbours several human pathogens and numerous previously uncharacterized pathogens. In this study, we identified and characterized a novel arenavirus (namely, plateau pika virus, PPV) from plateau pikas (Ochotona curzoniae) on the Qinghai-Tibet Plateau by virome analysis. Isolated PPV strains could replicate in several mammalian cells. We further investigated PPV pathogenesis using animal models. PPV administered via an intraventricular route caused trembling and sudden death in IFNαßR-/- mice, and pathological inflammatory lesions in brain tissue were observed. According to a retrospective serological survey in the geographical region where PPV was isolated, PPV-specific IgG antibodies were detected in 8 (2.4%) of 335 outpatients with available sera. Phylogenetic analyses revealed that this virus was clearly separated from previously reported New and Old World mammarenaviruses. Under the co-speciation framework, the estimated divergence time of PPV was 77-88 million years ago (MYA), earlier than that of OW and NW mammarenaviruses (26-34 MYA).


Assuntos
Arenaviridae , Lagomorpha , Animais , Humanos , Camundongos , Arenaviridae/genética , Filogenia , Estudos Retrospectivos , Tibet , Animais Selvagens
6.
Chemosphere ; 322: 138169, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36812994

RESUMO

Clarifying the sources and historical variation of metal(loid)s in agricultural river sediments is vital for watershed contamination control and environmental improvements. In this study, a systematical geochemical investigation of Pb isotopic characteristics and the spatial-temporal distribution of metal(loid)s abundances was conducted to delineate the origins of metal(loid)s (Cd, Zn, Cu, Pb, Cr, and As) in sediments from an agricultural river, Sichuan Province, Southwest China. The results showed significant enrichment of Cd and Zn in the whole watershed, with substantial anthropogenic contributions of 86.1% and 63.1% for the surface sediments, and 79.1% and 67.9% for the core sediments, respectively. As was mainly derived from natural sources. Cu, Cr, and Pb were originated from the mixing sources of natural and anthropogenic processes. The anthropogenic origin of Cd, Zn, and Cu in the watershed was closely correlated with agricultural activities. The profile of EF-Cd and EF-Zn displayed an increasing trend from the 1960s-1990s, and then kept a high value, which was consistent with the development of national agricultural activities. Pb isotopic signatures suggested multiple sources of the anthropogenic Pb contamination, including industrial/sewage discharge, coal combustion, and vehicle exhaust. The average anthropogenic 206Pb/207Pb ratio (1.1585) approximated that of local aerosols (1.1660), suggesting aerosol deposition was a crucial pathway of anthropogenic Pb input to sediment. Furthermore, the anthropogenic Pb percentages (mean of 52.3 ± 10.3%) from the EF approach were in line with that from the Pb isotopic method (mean of 45.5 ± 13.3%) for sediments under intense anthropogenic impacts.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Chumbo/análise , Cádmio/análise , Rios , Monitoramento Ambiental , Sedimentos Geológicos , China , Isótopos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Medição de Risco
7.
Animal Model Exp Med ; 6(1): 51-56, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36808904

RESUMO

BACKGROUND: New Omicron subvariants are emerging rapidly from BA.1 to BA.4 and BA.5. Their pathogenicity has changed from that of wild-type (WH-09) and Omicron variants have over time become globally dominant. The spike proteins of BA.4 and BA.5 that serve as the target for vaccine-induced neutralizing antibodies have also changed compared to the previous subvariants, which is likely to cause immune escape and the reduction of the protective effect of the vaccine. Our study addresses the above issues and provides a basis for formulating relevant prevention and control strategies. METHODS: We collected cellular supernatant and cell lysates and measured the viral titers, viral RNA loads, and E subgenomic RNA (E sgRNA) loads in different Omicron subvariants grown in Vero E6 cells, using WH-09 and Delta variants as a reference. Additionally, we evaluated the in vitro neutralizing activity of different Omicron subvariants and compared it to the WH-09 and Delta variants using macaque sera with different types of immunity. RESULTS: As the SARS-CoV-2 evolved into Omicron BA.1, the replication ability in vitro began to decrease. Then with the emergence of new subvariants, the replication ability gradually recovered and became stable in the BA.4 and BA.5 subvariants. In WH-09-inactivated vaccine sera, geometric mean titers of neutralization antibodies against different Omicron subvariants declined by 3.7~15.4-fold compared to those against WH-09. In Delta-inactivated vaccine sera, geometric mean titers of neutralization antibodies against Omicron subvariants declined by 3.1~7.4-fold compared to those against Delta. CONCLUSION: According to the findings of this research, the replication efficiency of all Omicron subvariants declined compared with WH-09 and Delta variants, and was lower in BA.1 than in other Omicron subvariants. After two doses of inactivated (WH-09 or Delta) vaccine, cross-neutralizing activities against various Omicron subvariants were seen despite a decline in neutralizing titers.


Assuntos
Anticorpos Neutralizantes , COVID-19 , SARS-CoV-2 , Replicação Viral , Animais , COVID-19/virologia , Macaca , SARS-CoV-2/fisiologia , RNA Subgenômico
8.
Cell Rep ; 41(12): 111845, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36493787

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages have escaped most receptor-binding domain (RBD)-targeting therapeutic neutralizing antibodies (NAbs), which proves that previous NAb drug screening strategies are deficient against the fast-evolving SARS-CoV-2. Better broad NAb drug candidate selection methods are needed. Here, we describe a rational approach for identifying RBD-targeting broad SARS-CoV-2 NAb cocktails. Based on high-throughput epitope determination, we propose that broad NAb drugs should target non-immunodominant RBD epitopes to avoid herd-immunity-directed escape mutations. Also, their interacting antigen residues should focus on sarbecovirus conserved sites and associate with critical viral functions, making the antibody-escaping mutations less likely to appear. Following these criteria, a featured non-competing antibody cocktail, SA55+SA58, is identified from a large collection of broad sarbecovirus NAbs isolated from SARS-CoV-2-vaccinated SARS convalescents. SA55+SA58 potently neutralizes ACE2-utilizing sarbecoviruses, including circulating Omicron variants, and could serve as broad SARS-CoV-2 prophylactics to offer long-term protection, especially for individuals who are immunocompromised or with high-risk comorbidities.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , SARS-CoV-2 , Anticorpos Amplamente Neutralizantes , Terapia Combinada de Anticorpos , Anticorpos Neutralizantes , Epitopos , Anticorpos Antivirais
9.
Virol J ; 19(1): 212, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494863

RESUMO

The COVID-19 pandemic, caused by the SARS-CoV-2 virus and its variants, has posed unprecedented challenges worldwide. Existing vaccines have limited effectiveness against SARS-CoV-2 variants. Therefore, novel vaccines to match mutated viral lineages by providing long-term protective immunity are urgently needed. We designed a recombinant adeno-associated virus 5 (rAAV5)-based vaccine (rAAV-COVID-19) by using the SARS-CoV-2 spike protein receptor binding domain (RBD-plus) sequence with both single-stranded (ssAAV5) and self-complementary (scAAV5) delivery vectors and found that it provides excellent protection from SARS-CoV-2 infection. A single-dose vaccination in mice induced a robust immune response; induced neutralizing antibody (NA) titers were maintained at a peak level of over 1:1024 more than a year post-injection and were accompanied by functional T-cell responses. Importantly, both ssAAV- and scAAV-based RBD-plus vaccines produced high levels of serum NAs against the circulating SARS-CoV-2 variants, including Alpha, Beta, Gamma and Delta. A SARS-CoV-2 virus challenge showed that the ssAAV5-RBD-plus vaccine protected both young and old mice from SARS-CoV-2 infection in the upper and lower respiratory tracts. Whole genome sequencing demonstrated that AAV vector DNA sequences were not found in the genomes of vaccinated mice one year after vaccination, demonstrating vaccine safety. These results suggest that the rAAV5-based vaccine is safe and effective against SARS-CoV-2 and several variants as it provides long-term protective immunity. This novel vaccine has a significant potential for development into a human prophylactic vaccination to help end the global pandemic.


Assuntos
COVID-19 , Parvovirinae , Animais , Humanos , Camundongos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Pandemias , Vacinas Sintéticas/genética , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes , Anticorpos Antivirais
10.
NPJ Vaccines ; 7(1): 144, 2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371432

RESUMO

Since the first outbreak in December 2019, SARS-CoV-2 has been constantly evolving and five variants have been classified as Variant of Concern (VOC) by the World Health Organization (WHO). These VOCs were found to enhance transmission and/or decrease neutralization capabilities of monoclonal antibodies and vaccine-induced antibodies. Here, we successfully designed and produced a recombinant COVID-19 vaccine in CHO cells at a high yield. The vaccine antigen contains four hot spot substitutions, K417N, E484K, N501Y and D614G, based on a prefusion-stabilized spike trimer of SARS-CoV-2 (S-6P) and formulated with an Alum/CpG 7909 dual adjuvant system. Results of immunogenicity studies showed that the variant vaccine elicited robust cross-neutralizing antibody responses against SARS-CoV-2 prototype (Wuhan) strain and all 5 VOCs. It further, stimulated a TH1 (T Helper type 1) cytokine profile and substantial CD4+ T cell responses in BALB/c mice and rhesus macaques were recorded. Protective efficacy of the vaccine candidate was evaluated in hamster and rhesus macaque models of SARS-CoV-2. In Golden Syrian hamsters challenged with Beta or Delta strains, the vaccine candidate reduced the viral loads in nasal turbinates and lung tissues, accompanied by significant weight gain and relieved inflammation in the lungs. In rhesus macaque challenged with prototype SARS-CoV-2, the vaccine candidate decreased viral shedding in throat, anal, blood swabs over time, reduced viral loads of bronchus and lung tissue, and effectively relieved the lung pathological inflammatory response. Together, our data demonstrated the broadly neutralizing activity and efficacy of the variant vaccine against both prototype and current VOCs of SARS-CoV-2, justifying further clinical development.

11.
Virulence ; 13(1): 1558-1572, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36082929

RESUMO

Influenza A virus (IAV) infection poses a substantial challenge and causes high morbidity and mortality. Exacerbated pulmonary inflammatory responses are the major causes of extensive diffuse alveolar immunopathological damage. However, the relationship between the extent of cytokine storm, neutrophils/macrophages infiltration, and different IAV infection dose and time still needs to be further elucidated, and it is still unclear whether the signal transduction and transcriptional activator 1/3 (STAT1/3) signalling pathway plays a beneficial or detrimental role. Here, we established a mouse model of high- and low-dose pH1N1 infection. We found that pH1N1 infection induced robust and early pathological damage and cytokine storm in an infection dose- and time-dependent manner. High-dose pH1N1 infection induced massive and sustained recruitment of neutrophils as well as a higher ratio of M1:M2, which may contribute to severe lung immunopathological damage. pH1N1 infection activated dose- and time-dependent STAT1 and STAT3. Inhibition of STAT1 and/or STAT3 aggravated low-dose pH1N1 infection, induced lung damage, and decreased survival rate. Appropriate activation of STAT1/3 provided survival benefits and pathological improvement during low-dose pH1N1 infection. These results demonstrate that high-dose pH1N1 infection induces robust and sustained neutrophil infiltration, imbalanced macrophage polarization, excessive and earlier cytokine storm, and STAT1/3 activation, which are associated with pulmonary dysregulated proinflammatory responses and progress of acute lung injury. The severe innate immune responses may be the threshold at which protective functions give way to immunopathology, and assessing the magnitude of host innate immune responses is necessary in adjunctive immunomodulatory therapy for alleviating influenza-induced pneumonia.


Assuntos
Imunidade Inata , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Síndrome da Liberação de Citocina , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Pulmão/imunologia , Pulmão/patologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/patologia , Camundongos , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
12.
Sci China Life Sci ; 65(12): 2517-2526, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35696017

RESUMO

Enterovirus A71 (EV-A71) causes major outbreaks of hand, foot, and mouth disease (HFMD) in many countries, most frequently affecting children, and a small proportion of cases may lead to death. Currently, no vaccine is available in most endemic regions, and no licenced treatments for EV-A71 infection are available. Here, we characterize a human monoclonal antibody (HuMAb), E1, by screening a Fab antibody phage library derived from patients who recovered from EV-A71 infection. E1 exhibits strong neutralizing activity against EV-A71 virus in cells. The cryo-electron microscopy (cryo-EM) structures of the EV-A71 virion in complex with E1 Fab fragments demonstrated that E1 recognized an epitope formed by residues in the BC and HI loops of VP1. In a mouse model, E1 effectively protected against lethal EV-A71 challenge in both prophylactic and therapeutic treatment. In particular, E1 significantly reduces virus titers and muscle damage. E1 might represent a potential adjunct to EV-A71 treatment.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Camundongos , Criança , Animais , Humanos , Anticorpos Neutralizantes , Microscopia Crioeletrônica , Infecções por Enterovirus/epidemiologia , Antígenos Virais
14.
Vaccine ; 40(32): 4609-4616, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35738970

RESUMO

The mass inoculation of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine to induce herd immunity is one of the most effective measures to fight COVID-19. The vaccination of pregnant women cannot only avoid or reduce the probability of infectious diseases, but also offers the most effective and direct protection for neonates by means of passive immunization. However, there is no randomized clinical data to ascertain whether the inactivated vaccination of pregnant women or women of childbearing age can affect conception and the fetus. We found that human angiotensin-converting enzyme 2 (hACE2) mice that were vaccinated with two doses of CoronaVac (an inactivated SARS-CoV-2 vaccine) before and during pregnancy exhibited normal weight changes and reproductive performance indices; the physical development of their offspring was also normal. Following intranasal inoculation with SARS-CoV-2, pregnant mice in the immunization group all survived; reproductive performance indices and the physical development of offspring were all normal. In contrast, mice in the non-immunization group all died before delivery. Analyses showed that inoculation of CoronaVac was safe and did not exert any significant effects on pregnancy, lactation, or the growth of offspring in hACE2 mice. Vaccination effectively protected the pregnant mice against SARS-CoV-2 infection and had no adverse effects on the growth and development of the offspring, thus suggesting that inoculation with an inactivated SARS-CoV-2 vaccine may be an effective strategy to prevent infection in pregnant women.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Lactação , Enzima de Conversão de Angiotensina 2 , Animais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , Feminino , Humanos , Camundongos , Camundongos Transgênicos , Gravidez , SARS-CoV-2 , Vacinas de Produtos Inativados
15.
Chin Med J (Engl) ; 135(7): 799-805, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35671181

RESUMO

BACKGROUND: The new emerging avian influenza A H7N9 virus, causing severe human infection with a mortality rate of around 41%. This study aims to provide a novel treatment option for the prevention and control of H7N9. METHODS: H7 hemagglutinin (HA)-specific B cells were isolated from peripheral blood plasma cells of the patients previously infected by H7N9 in Jiangsu Province, China. The human monoclonal antibodies (mAbs) were generated by amplification and cloning of these HA-specific B cells. First, all human mAbs were screened for binding activity by enzyme-linked immunosorbent assay. Then, those mAbs, exhibiting potent affinity to recognize H7 HAs were further evaluated by hemagglutination-inhibiting (HAI) and microneutralization in vitro assays. Finally, the lead mAb candidate was selected and tested against the lethal challenge of the H7N9 virus using murine models. RESULTS: The mAb 6-137 was able to recognize a panel of H7 HAs with high affinity but not HA of other subtypes, including H1N1 and H3N2. The mAb 6-137 can efficiently inhibit the HA activity in the inactivated H7N9 virus and neutralize 100 tissue culture infectious dose 50 (TCID50) of H7N9 virus (influenza A/Nanjing/1/2013) in vitro, with neutralizing activity as low as 78 ng/mL. In addition, the mAb 6-137 protected the mice against the lethal challenge of H7N9 prophylactically and therapeutically. CONCLUSION: The mAb 6-137 could be an effective antibody as a prophylactic or therapeutic biological treatment for the H7N9 exposure or infection.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Subtipo H7N9 do Vírus da Influenza A , Vacinas contra Influenza , Influenza Aviária , Influenza Humana , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais , Hemaglutininas , Humanos , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/prevenção & controle , Camundongos
16.
Signal Transduct Target Ther ; 7(1): 124, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35436986

RESUMO

Variants of concern (VOCs) like Delta and Omicron, harbor a high number of mutations, which aid these viruses in escaping a majority of known SARS-CoV-2 neutralizing antibodies (NAbs). In this study, Rhesus macaques immunized with 2-dose inactivated vaccines (Coronavac) were boosted with an additional dose of homologous vaccine or an RBD-subunit vaccine, or a bivalent inactivated vaccine (Beta and Delta) to determine the effectiveness of sequential immunization. The booster vaccination significantly enhanced the duration and levels of neutralizing antibody titers against wild-type, Beta, Delta, and Omicron. Animals administered with an indicated booster dose and subsequently challenged with Delta or Omicron variants showed markedly reduced viral loads and improved histopathological profiles compared to control animals, indicating that sequential immunization could protect primates against Omicron. These results suggest that sequential immunization of inactivated vaccines or polyvalent vaccines could be a potentially effective countermeasure against newly emerging variants.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Macaca mulatta , SARS-CoV-2/genética , Vacinação , Vacinas de Produtos Inativados/genética
18.
J Environ Manage ; 311: 114865, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35279491

RESUMO

Rubber dams are widely used in urban rivers for landscape construction and flood control. However, the increased water residence time by dams usually causes phytoplankton accumulation. Developing a greater understanding of the phytoplankton dynamics and the effecting factors is essential for the eutrophication control of dammed rivers. Here, we investigated the variations in biomass and structure of phytoplankton communities along an urban landscape river with 30 rubber dams, and the main controlling factors during a 2-yr field monitoring. The biomass of phytoplankton significantly increased from 12.7 µg/L-Chl a and 1.14 × 107 ind./L-cells at the natural river part above dams to 65.2 µg/L-Chl a and 1.16 × 108 ind./L-cells at the 30th dam on average. There were different dominant taxa of phytoplankton between river sections with and without dams in different seasons. As Bacillariophyta dominated at the natural river part above dams throughout the year, accounting for 64.6% on average, and dominated at the 13th and 30th dams during the cold seasons (69.6% on average). But during the warm seasons, Cyanophyta and Chlorophyta increased obviously in the dammed river sections and became dominant taxa at the 30th dam, accounting for 55.9% and 34.7% respectively. The α-diversity of phytoplankton decreased along the series of dams. While the ß-diversity between river sections with and without dams increased because of species replacement. Redundancy analysis revealed that nutrients, flow velocity and temperature were the main factors influencing the spatial-temporal variation in phytoplankton community structure in this river. High-frequency monitoring data further indicated that phosphorus and discharge explained most of the variations in phytoplankton biomass within the 13th dam impoundment. It suggested that management strategies should focus on reducing the phosphorus input concentration under 0.164 mg/L and increase the discharge higher than 0.64 m3/s during warm seasons, to prevent phytoplankton bloom and further eutrophication problems in this dammed river.

19.
Animal Model Exp Med ; 5(1): 89-93, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35213787

RESUMO

BACKGROUND: The Omicron (B.1.1.529) SARS-COV-2 variant has raised serious concerns because of its unprecedented rapid rate of spreading and the fact that there are 36 mutations in the spike protein. Since the vaccine-induced neutralizing antibody targets are the spike protein, this may lead to the possibility of vaccine-induced humoral immunity escape. METHODS: We measured the neutralizing activity in vitro for Omicron and compared this with wild type (WH-09) and Delta variants in human and monkey sera from different types of immunity. The monkey sera samples were collected at 1 and 3 months post three-dose inactivated (PiCoVacc) and recombinant protein (ZF2001) vaccination. Human sera were collected from 1 month post three-dose inactivated vaccination. RESULTS: In inactivated vaccine sera, at 1/3 months post three-dose, geometric mean titers (GMTs) of neutralization antibody (NAb) against the Omicron variant were 4.9/5.2-fold lower than those of the wild type. In recombinant protein vaccine sera, GMTs of NAb against Omicron were 15.7/8.9-fold lower than those of the wild type. In human sera, at 1 month post three-dose inactivated vaccination, GMTs of NAb against Omicron were 3.1-fold lower than those of the wild type. CONCLUSION: This study demonstrated that despite a reduction in neutralization titers, cross-neutralizing activity against Omicron and Delta variants was still observed after three doses of inactivated and recombinant protein vaccination.


Assuntos
Anticorpos Antivirais/sangue , Vacinas contra COVID-19/administração & dosagem , COVID-19 , Reações Cruzadas , SARS-CoV-2 , Animais , Anticorpos Neutralizantes/sangue , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Haplorrinos , Humanos , Testes de Neutralização , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
20.
Hum Vaccin Immunother ; 18(1): 2016201, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35061975

RESUMO

Genetic optimization of Nucleic Acid immunogens is important for potentially improving their immune potency. A COVID-19 DNA vaccine is in phase III clinical trial which is based on a promising highly developable technology platform. Here, we show optimization in mice generating a pGX-9501 DNA vaccine encoding full-length spike protein, which results in induction of potent humoral and cellular immune responses, including neutralizing antibodies, that block hACE2-RBD binding of live CoV2 virus in vitro. Optimization resulted in improved induction of cellular immunity by pGX-9501 as demonstrated by increased IFN-γ expression in both CD8+ and CD4 + T cells and this was associated with more robust antiviral CTL responses compared to unoptimized constructs. Vaccination with pGX-9501 induced subsequent protection against virus challenge in a rigorous hACE2 transgenic mouse model. Overall, pGX-9501 is a promising optimized COVID-19 DNA vaccine candidate inducing humoral and cellular immunity contributing to the vaccine's protective effects.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Sequência de Bases , COVID-19/prevenção & controle , Camundongos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
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