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1.
BMC Med ; 21(1): 233, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400857

RESUMO

BACKGROUND: Several COVID-19 vaccines are in widespread use in China. Few data exist on comparative immunogenicity of different COVID-19 vaccines given as booster doses. We aimed to assess neutralizing antibody levels raised by injectable and inhaled aerosolized recombinant adenovirus type 5 (Ad5)-vectored COVID-19 vaccine as a heterologous booster after an inactivated COVID-19 vaccine two-dose primary series. METHODS: Using an open-label prospective cohort design, we recruited 136 individuals who had received inactivated vaccine primary series followed by either injectable or inhaled Ad5-vectored vaccine and measured neutralizing antibody titers against ancestral SARS-CoV-2 virus and Omicron BA.1 and BA.5 variants. We also measured neutralizing antibody levels in convalescent sera from 39 patients who recovered from Omicron BA.2 infection. RESULTS: Six months after primary series vaccination, neutralizing immunity against ancestral SARS-CoV-2 was low and neutralizing immunity against Omicron (B.1.1.529) was lower. Boosting with Ad5-vectored vaccines induced a high immune response against ancestral SARS-CoV-2. Neutralizing responses against Omicron BA.5 were ≥ 80% lower than against ancestral SARS-CoV-2 in sera from prime-boost subjects and in convalescent sera from survivors of Omicron BA.2 infection. Inhaled aerosolized Ad5-vectored vaccine was associated with greater neutralizing titers than injectable Ad5-vectored vaccine against ancestral and Omicron SARS-CoV-2 variants. CONCLUSIONS: These findings support the current strategy of heterologous boosting with injectable or inhaled Ad5-vectored SARS-CoV-2 vaccination of individuals primed with inactivated COVID-19 vaccine.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Estudos Prospectivos , SARS-CoV-2
2.
Lancet ; 396(10249): 479-488, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32702299

RESUMO

BACKGROUND: This is the first randomised controlled trial for assessment of the immunogenicity and safety of a candidate non-replicating adenovirus type-5 (Ad5)-vectored COVID-19 vaccine, aiming to determine an appropriate dose of the candidate vaccine for an efficacy study. METHODS: This randomised, double-blind, placebo-controlled, phase 2 trial of the Ad5-vectored COVID-19 vaccine was done in a single centre in Wuhan, China. Healthy adults aged 18 years or older, who were HIV-negative and previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-free, were eligible to participate and were randomly assigned to receive the vaccine at a dose of 1 × 1011 viral particles per mL or 5 × 1010 viral particles per mL, or placebo. Investigators allocated participants at a ratio of 2:1:1 to receive a single injection intramuscularly in the arm. The randomisation list (block size 4) was generated by an independent statistician. Participants, investigators, and staff undertaking laboratory analyses were masked to group allocation. The primary endpoints for immunogenicity were the geometric mean titres (GMTs) of specific ELISA antibody responses to the receptor binding domain (RBD) and neutralising antibody responses at day 28. The primary endpoint for safety evaluation was the incidence of adverse reactions within 14 days. All recruited participants who received at least one dose were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, NCT04341389. FINDINGS: 603 volunteers were recruited and screened for eligibility between April 11 and 16, 2020. 508 eligible participants (50% male; mean age 39·7 years, SD 12·5) consented to participate in the trial and were randomly assigned to receive the vaccine (1 × 1011 viral particles n=253; 5 × 1010 viral particles n=129) or placebo (n=126). In the 1 × 1011 and 5 × 1010 viral particles dose groups, the RBD-specific ELISA antibodies peaked at 656·5 (95% CI 575·2-749·2) and 571·0 (467·6-697·3), with seroconversion rates at 96% (95% CI 93-98) and 97% (92-99), respectively, at day 28. Both doses of the vaccine induced significant neutralising antibody responses to live SARS-CoV-2, with GMTs of 19·5 (95% CI 16·8-22·7) and 18·3 (14·4-23·3) in participants receiving 1 × 1011 and 5 × 1010 viral particles, respectively. Specific interferon γ enzyme-linked immunospot assay responses post vaccination were observed in 227 (90%, 95% CI 85-93) of 253 and 113 (88%, 81-92) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Solicited adverse reactions were reported by 183 (72%) of 253 and 96 (74%) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Severe adverse reactions were reported by 24 (9%) participants in the 1 × 1011 viral particles dose group and one (1%) participant in the 5 × 1010 viral particles dose group. No serious adverse reactions were documented. INTERPRETATION: The Ad5-vectored COVID-19 vaccine at 5 × 1010 viral particles is safe, and induced significant immune responses in the majority of recipients after a single immunisation. FUNDING: National Key R&D Programme of China, National Science and Technology Major Project, and CanSino Biologics.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Adenoviridae , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19 , Vacinas contra COVID-19 , China , Infecções por Coronavirus/imunologia , Método Duplo-Cego , Feminino , Vetores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinas Virais/administração & dosagem , Adulto Jovem
3.
Lancet ; 395(10240): 1845-1854, 2020 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-32450106

RESUMO

BACKGROUND: A vaccine to protect against COVID-19 is urgently needed. We aimed to assess the safety, tolerability, and immunogenicity of a recombinant adenovirus type-5 (Ad5) vectored COVID-19 vaccine expressing the spike glycoprotein of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain. METHODS: We did a dose-escalation, single-centre, open-label, non-randomised, phase 1 trial of an Ad5 vectored COVID-19 vaccine in Wuhan, China. Healthy adults aged between 18 and 60 years were sequentially enrolled and allocated to one of three dose groups (5 × 1010, 1 × 1011, and 1·5 × 1011 viral particles) to receive an intramuscular injection of vaccine. The primary outcome was adverse events in the 7 days post-vaccination. Safety was assessed over 28 days post-vaccination. Specific antibodies were measured with ELISA, and the neutralising antibody responses induced by vaccination were detected with SARS-CoV-2 virus neutralisation and pseudovirus neutralisation tests. T-cell responses were assessed by enzyme-linked immunospot and flow-cytometry assays. This study is registered with ClinicalTrials.gov, NCT04313127. FINDINGS: Between March 16 and March 27, 2020, we screened 195 individuals for eligibility. Of them, 108 participants (51% male, 49% female; mean age 36·3 years) were recruited and received the low dose (n=36), middle dose (n=36), or high dose (n=36) of the vaccine. All enrolled participants were included in the analysis. At least one adverse reaction within the first 7 days after the vaccination was reported in 30 (83%) participants in the low dose group, 30 (83%) participants in the middle dose group, and 27 (75%) participants in the high dose group. The most common injection site adverse reaction was pain, which was reported in 58 (54%) vaccine recipients, and the most commonly reported systematic adverse reactions were fever (50 [46%]), fatigue (47 [44%]), headache (42 [39%]), and muscle pain (18 [17%]. Most adverse reactions that were reported in all dose groups were mild or moderate in severity. No serious adverse event was noted within 28 days post-vaccination. ELISA antibodies and neutralising antibodies increased significantly at day 14, and peaked 28 days post-vaccination. Specific T-cell response peaked at day 14 post-vaccination. INTERPRETATION: The Ad5 vectored COVID-19 vaccine is tolerable and immunogenic at 28 days post-vaccination. Humoral responses against SARS-CoV-2 peaked at day 28 post-vaccination in healthy adults, and rapid specific T-cell responses were noted from day 14 post-vaccination. Our findings suggest that the Ad5 vectored COVID-19 vaccine warrants further investigation. FUNDING: National Key R&D Program of China, National Science and Technology Major Project, and CanSino Biologics.


Assuntos
Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/administração & dosagem , Adenoviridae , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus , COVID-19 , Vacinas contra COVID-19 , China , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/uso terapêutico , Vacinas Virais/efeitos adversos , Vacinas Virais/uso terapêutico , Adulto Jovem
4.
Am J Trop Med Hyg ; 101(3): 510-512, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31287047

RESUMO

We aimed to investigate the epidemic situation of tuberculosis (TB) in prisons in the central region of China. Tuberculosis screening was carried out in two prisons in middle China. A sum of 3,459 prisoners accepted chest X-ray examination; 40 of them were diagnosed as active TB patients. The active TB prevalence (1,156/105) was significantly higher than that of the province and China's general population (P < 0.01). As for gender, TB prevalence in men's prison (1,589/105) was higher than that in the women's prison (946/105). Nevertheless, the risk of having TB in women's prison was much higher than that in the men's prison when compared with the TB prevalence from the province (women: OR = 2.37, 95% CI: 1.34, 4.22; men: OR = 1.53, 95% CI: 0.90, 2.60) and the China's general population (women: OR = 3.30, 95% CI: 2.15, 5.09; men: OR = 2.06, 95% CI: 1.29, 3.30). In view of the severe epidemic situation of TB in prisons, integrating medical resources to establish a consummate and effective management system is necessary.


Assuntos
Prisioneiros , Prisões/estatística & dados numéricos , Tuberculose/epidemiologia , China , Epidemias , Feminino , Humanos , Masculino , Programas de Rastreamento , Prevalência
5.
Influenza Other Respir Viruses ; 11(2): 148-156, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27465959

RESUMO

BACKGROUND: Influenza is an important cause of respiratory illness in children, but data are limited on hospitalized children with laboratory-confirmed influenza in China. METHODS: We conducted active surveillance for severe acute respiratory infection (SARI; fever and at least one sign or symptom of acute respiratory illness) among hospitalized pediatric patients in Jingzhou, Hubei Province, from April 2010 to April 2012. Data were collected from enrolled SARI patients on demographics, underlying health conditions, clinical course of illness, and outcomes. Nasal swabs were collected and tested for influenza viruses by reverse transcription polymerase chain reaction. We described the clinical and epidemiological characteristics of children with influenza and analyzed the association between potential risk factors and SARI patients with influenza. RESULTS: During the study period, 15 354 children aged <15 years with signs and symptoms of SARI were enrolled at hospital admission. severe acute respiratory infection patients aged 5-15 years with confirmed influenza (H3N2) infection were more likely than children without influenza to have radiographic diagnosis of pneumonia (11/31, 36% vs 15/105, 14%. P<.05). Only 16% (1116/7145) of enrolled patients had received seasonal trivalent influenza vaccination within 12 months of hospital admission. Non-vaccinated influenza cases were more likely than vaccinated influenza cases to have pneumonia (31/133, 23% vs 37/256, 15%, P<.05). severe acute respiratory infection cases aged 5-15 years diagnosed with influenza were also more likely to have a household member who smoked cigarettes compared with SARI cases without a smoking household member (54/208, 26% vs 158/960, 16%, P<.05). CONCLUSIONS: Influenza A (H3N2) virus infection was an important contributor to pneumonia requiring hospitalization. Our results highlight the importance of surveillance in identifying factors for influenza hospitalization, monitoring adherence to influenza prevention and treatment strategies, and evaluating the disease burden among hospitalized pediatric SARI patients. Influenza vaccination promotion should target children.


Assuntos
Influenza Humana/epidemiologia , Infecções Respiratórias/epidemiologia , Doença Aguda/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Características da Família , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/complicações , Influenza Humana/virologia , Masculino , Pneumonia/epidemiologia , Pneumonia/etiologia , Pneumonia/virologia , Infecções Respiratórias/virologia , Estações do Ano , Vacinação
6.
Virol J ; 11: 142, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25107552

RESUMO

BACKGROUND: Respiratory Syncytial Virus (RSV) is an important human respiratory pathogen, particularly of infants and older adults, and despite several decades of research and development, no licensed vaccine is available. Studies have confirmed that enhancement of RSV disease does not occur after inoculation with RSV live-attenuated vaccine candidates, making such vaccines preferable. In this paper, reverse genetics was used to construct two recombinant viruses, a recombinant Long strain (rLong) and rLong-∆G-EGFP; rLong-∆G-EGFP is a recombinant mutant in which G was replaced with the EGFP gene, based on the Long strain of RSV. RESULTS: Both rLong and rLong-∆G-EGFP were constructed successfully and recovered in Hep-2 cells, and autofluorescence was observed in rLong-∆G-EGFP-infected cells during consecutive passages. Titers of rLong and rLong-∆G-EGFP were ~100-fold lower than the parental strain. Although virulence was attenuated, high titers of neutralizing antibodies were induced in BALB/c mice after being inoculated with recombinant viruses in a three-dose schedule. Unexpectedly, the neutralizing antibody titer in rLong-∆G-EGFP-immunized recipients did not decline significantly compared with the rLong strain. Protective efficacy of recombinant viruses in lung tissue was up to 100%, and the serum neutralizing antibody levels could stabilize at 21 days with no significant fall post-challenge. Enzyme-linked immunospot (ELISPOT) assays showed that both recombinant viruses were capable of inducing CD8+ T cell immune responses, which are crucial for virus clearance, and that rLong stimulated a higher level of IFN-γ production by comparison. In terms of inducing a balanced immune response, rLong-∆G-EGFP elicited slightly higher levels of IgG2a antibodies and lower levels of IgG1/IgG2a than the rLong virus. CONCLUSIONS: This study suggested that immunization with rLong and rLong-∆G-EGFP were immunogenic and protected against RSV infection in the lower respiratory tract of BALB/c mice better than in the nose. Because of a relative low IgG1/IgG2a ratio, rLong-∆G-EGFP was more inclined to make CD4+ T cells, shifting toward a Th1-type response, indicating that the generation of a more balanced Th1/Th2 response was desirable. This explorative study on the recombinant Long viruses also contributed to obtaining more RSV attenuated candidates by a reverse genetics approach.


Assuntos
Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/imunologia , Genética Reversa/métodos , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Expressão Gênica , Genes Reporter , Engenharia Genética , Vetores Genéticos/genética , Células Hep G2 , Humanos , Imunidade Celular , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano/crescimento & desenvolvimento , Subpopulações de Linfócitos T/imunologia , Ensaio de Placa Viral , Replicação Viral
7.
Gene ; 517(2): 218-23, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23147264

RESUMO

Endothelial nitric oxide synthase (eNOS) plays an important role in mediating endothelium-dependent vasodilatation and antithrombotic action and is thus involved in the development of ischemic stroke (IS). Controversial results regarding the association of eNOS gene variable number of tandem repeats (VNTR) polymorphism with IS have been reported by conventional PCR-polyacrylamide gel electrophoresis methods. We aimed to identify any common association of eNOS gene VNTR polymorphism with IS in Chinese Han population by capillary electrophoresis (CE). The VNTR polymorphism of 27 bp within the eNOS intron-4 was determined by CE with specially designed tailed primers in Chinese Han patients with IS (n=457) and matched elderly controls without IS (n=457). Significant differences in BMI, WHR, hypertension, diabetes, smoking, TG, HDL, LDL, LDL, and FBG were observed between cases and controls. The distributions of eNOS VNTR polymorphism were not significantly associated with IS after adjustment for cardiovascular risk factors (OR=1.18, 95% CI: 0.82-1.69). This finding was consistent with the further meta-analysis in Asians. The meta-analysis in Americans demonstrated that 4a/4b+4a/4a genotype was significantly associated with IS risk with an OR of 1.54 (95% CI, 1.09-2.17) compared with the 4b/4b genotype. Our data suggests that BMI, WHR, hypertension, diabetes, smoking, TG, LDL, and FBG may increase the risk of IS. However, eNOS VNTR polymorphism may be not an independent major contributor for IS in Chinese Han population. The VNTR polymorphism might be associated with IS in Americans based on meta-analysis.


Assuntos
Povo Asiático/genética , Isquemia Encefálica/genética , Repetições Minissatélites , Óxido Nítrico Sintase Tipo III/genética , Idoso , Isquemia Encefálica/etnologia , Primers do DNA , Eletroforese Capilar , Feminino , Humanos , Íntrons , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade
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