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1.
Lupus ; 33(5): 450-461, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38335115

RESUMO

OBJECTIVES: We evaluated the immunogenicity and safety of BNT162b2 vaccination in adolescents with systemic lupus erythematosus (adoSLE) receiving either high- or low-dose immunosuppressant (High-IS and Low-IS). METHODS: Patients aged 12-18 years diagnosed with SLE were enrolled. High-IS was defined as >7.5 mg/day prednisolone or with other immunosuppressant, while Low-IS was defined as only ≤7.5 mg/day of prednisolone and no immunosuppressant. Two doses of BNT162b2 vaccination were given 4 weeks apart, followed by a booster (third) dose at 4-6 months later. Anti-spike receptor binding domain (anti-RBD) IgG against Wuhan, neutralising antibody (NT) against Wuhan and Omicron variants, and cellular immune response by IFN-γ-ELISpot assay were evaluated following vaccination. Adverse events (AEs) and SLE flare were monitored. RESULTS: A total of 73 participants were enrolled, 40 and 33 in the High-IS and Low-IS group, respectively. At 4 weeks following the 2nd dose, overall anti-RBD IgG seropositivity was 97.3%, with no difference between the groups (p = .498). AdoSLE on High-IS had lower anti-RBD IgG (p < .001), Wuhan NT (p < .001), and IFN-γ-ELISpot (p = .022) than those on Low-IS. A 3rd dose induced significantly higher antibody responses than after the 2nd dose (p < .001) in both groups and established seroconversion against Omicron variants, with persistent lower antibody levels in High-IS group. SELENA-SLEDAI scores within 12 weeks after 2-dose vaccination was higher than before vaccination (3.1 vs 2.5; p < .036); however, the occurrence of disease flare by SELENA-SLEDAI flare index was not different after vaccination compared to before vaccination, consistent across groups. Non-severe AEs occurred similarly in both groups. CONCLUSION: AdoSLE on High-IS induced lower SARS-CoV-2 vaccine immune responses than Low-IS. Vaccination can increase disease activity and requires close monitoring for disease flare.


Assuntos
Lúpus Eritematoso Sistêmico , Humanos , Adolescente , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , Exacerbação dos Sintomas , Prednisolona , Imunossupressores/efeitos adversos , Imunoglobulina G , Anticorpos Antivirais , Vacinação , Imunogenicidade da Vacina
2.
J Med Virol ; 92(11): 2582-2592, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32470142

RESUMO

Rotavirus infections have become one of the most common causes of infectious gastroenteritis in children. Although rotavirus infections have been intensively studied in infants and young children, the study in adults has been limited. As such, this study assessed the prevalence of rotaviruses and performed the molecular characterization of rotaviruses circulating in Thai adults experiencing acute gastroenteritis between January 2018 and December 2018. Group A human rotaviruses were detected in 100 feces samples by rapid immunochromatography. The peak incidence of infection occurred in February and began to decline in the summer months. From January 2018 to December 2018, there were 1344 acute gastroenteritis adult cases in the Hospital for Tropical Diseases, Bangkok, Thailand. Among these, 310 cases were rotavirus-suspected cases. Only 100 samples tested positive for rotavirus via an immunochromatography test. Twentynine out of the 100 rotavirus-positive samples were further characterized by real-time polymerase chain reaction. The G3[P8] strain was identified as the most prevalent (31.0%) followed by G1P[8], G8P[8] and G9P[8], and G2P[8], which accounted for 20.8%, 17.2%, and 13.8%, respectively. Because of the detection of rare rotavirus genotypes, such as G8, the surveillance of rotavirus epidemiology is crucial in monitoring new emergences of rotavirus strains, leading to a better understanding of the effects of strain variation for further vaccine development.


Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Filogenia , Prevalência , Rotavirus/classificação , Rotavirus/isolamento & purificação , Estações do Ano , Tailândia/epidemiologia , Adulto Jovem
3.
Proteomics ; 18(23): e1800215, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30365215

RESUMO

The clinical sign of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) in humans is increased vascular permeability. Virus-specific factors and host factors, including secreted cytokines and especially TNF-α, are suggested as having roles in the pathogenesis of these conditions. Proteomic analysis with MS is performed in membrane fraction isolated from human endothelial cells (EA.hy926) upon DENV infection and TNF-α treatment. In the 451 altered proteins that are identified, decreased plectin expression is revealed by Western blot analysis, while immunofluorescence staining (IFA) shows actin stress fiber rearrangement and decreased VE-cadherin in treated EA.hy926 cells. In vitro vascular permeability assay was used to determine transepithelial electrical resistance (TEER) in EA.hy926 cells seeded on collagen-coated Transwell inserts. The low level of TEER, the low expression of plectin and VE-cadherin, and the unusual organization of actin stress fiber are found to be correlated with increased membrane permeability in DENV2 and TNF-α-treated EA.hy926 cells. Similar results are observed when using siRNA knockdown plectin in mock EA.hy926 cells. This study provides better understanding of the role that disruption of cytoskeleton linker protein plays in increased vascular permeability, and suggests these factors as major contributors to vascular leakage in DHF/DSS patients.


Assuntos
Vírus da Dengue/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/virologia , Plectina/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Linhagem Celular , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Humanos , RNA Interferente Pequeno/metabolismo
4.
J Virol ; 91(15)2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490598

RESUMO

We have developed pandemic live attenuated influenza vaccines (pLAIVs) against clade 1 H5N1 viruses on an Ann Arbor cold-adapted (ca) backbone that induced long-term immune memory. In 2015, many human infections caused by a new clade (clade 2.2.1.1) of goose/Guangdong (gs/GD) lineage H5N1 viruses were reported in Egypt, which prompted updating of the H5N1 pLAIV. We explored two strategies to generate suitable pLAIVs. The first approach was to modify the hemagglutinin gene of a highly pathogenic wild-type (wt) clade 2.2.1.1 virus, A/Egypt/N03434/2009 (Egy/09) (H5N1), with its unmodified neuraminidase (NA) gene; this virus was designated Egy/09 ca The second approach was to select a low-pathogenicity avian influenza H5 virus that elicited antibodies that cross-reacted with a broad range of H5 viruses, including the Egypt H5N1 viruses, and contained a novel NA subtype for humans. We selected the low-pathogenicity A/duck/Hokkaido/69/2000 (H5N3) (dk/Hok/00) virus for this purpose. Both candidate vaccines were attenuated and immunogenic in ferrets, inducing antibodies that neutralized homologous and heterologous H5 viruses with different degrees of cross-reactivity; Egy/09 ca vaccine antisera were more specific for the gs/GD lineage viruses but did not neutralize recent North American isolates (clade 2.3.4.4), whereas antisera from dk/Hok/69 ca-vaccinated ferrets cross-reacted with clade 2.3.4.4 and 2.2.1 viruses but not clade 1 or 2.1 viruses. When vaccinated ferrets were challenged with homologous and heterologous H5 viruses, challenge virus replication was reduced in the respiratory tract. Thus, the two H5 pLAIV candidates are suitable for clinical development to protect humans from infection with different clades of H5 viruses.IMPORTANCE In response to the continuing evolution of H5N1 avian influenza viruses and human infections, new candidate H5 live attenuated vaccines were developed by using two different approaches: one targeted a specific circulating strain in Egypt, and the other was based on a virus that elicits broadly cross-reactive antibodies against a wide range of H5 viruses. Both candidate vaccines were immunogenic and exhibited protective efficacy in ferrets. Our study permits a comparison of the two approaches, and the data support the further development of both vaccine viruses to optimally prepare for the further spread of clade 2.2.1 or 2.3.4.4 viruses.


Assuntos
Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Reações Cruzadas , Modelos Animais de Doenças , Furões , Genótipo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Vacinas contra Influenza/isolamento & purificação , Testes de Neutralização , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Vírus Reordenados/genética , Vírus Reordenados/imunologia , Sistema Respiratório/virologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/isolamento & purificação , Carga Viral
5.
Asian Pac J Allergy Immunol ; 36(1): 58-68, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28802028

RESUMO

BACKGROUND: The level of virulence of H5N1 highly pathogenic avian influenza (HPAI) virus was higher than those of the other virus subtypes. It has been suggested that the nonstructural (NS) gene might be a factor contributing to H5N1 HPAI virulence. OBJECTIVES: To determine the efficiency of the NS genomic segment of H5N1 HPAI virus on governing viral infectivity and cytokine induction in monocytic cells compared to other virus strain/subtypes. METHODS: By reverse genetics, five reassortant influenza viruses carrying the NS genomic segment derived from seasonal influenza A(H1N1), 2009 pandemic A(H1N1), A(H3N2) or H5N1 HPAI virus in the backbone of A/Puerto Rico/8/34 H1N1 (PR8) virus were constructed together with the reassorted PR8 virus control, i.e., rgH1N1sea-NS, rgH1N1pdm-NS, rgH3N2-NS, rgH5N1-NS and rgPR8 viruses, respectively. These reverse genetics-derived viruses (rg-viruses) were used to infect monocytic cells for 24 hours prior to determining intracellular influenza nucleoprotein (NP) levels and cytokine induction by flow cytometry. RESULTS: U937 cells were significantly more susceptible to rgPR8 control virus than THP-1 cells; thus, U937 cells were chosen for further study. The number of U937-infected cells (NP+ cells) and the numbers of infected cells that expressed IFN-α (NP+IFN-α+ cell) obtained with rgH5N1-NS virus infection were significantly higher than the others, except for cells infected with the rgH1N1pdm-NS virus. Nevertheless, the numbers of U937 cells that expressed NP+IL-1ß+ were comparable upon infection with any of the rg-viruses; almost none expressed TNF-α. CONCLUSIONS: The H5N1 NS genomic segment distinctly up-regulated the viral infectivity and induction of IFN-α compared to the rgPR8, rgH1N1sea-NS and rgH3N2-NS viruses.


Assuntos
Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Proteínas não Estruturais Virais/genética , Virulência/genética , Animais , Citocinas/biossíntese , Cães , Genes Virais , Humanos , Células Madin Darby de Rim Canino , Monócitos/imunologia , Monócitos/virologia , Células U937
6.
J Immunol ; 195(9): 4378-86, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26408671

RESUMO

Studies of influenza-specific immune responses in humans have largely assessed systemic responses involving serum Ab and peripheral blood T cell responses. However, recent evidence indicates that tissue-resident memory T (TRM) cells play an important role in local murine intrapulmonary immunity. Rhesus monkeys were pulmonary exposed to 2009 pandemic H1N1 virus at days 0 and 28 and immune responses in different tissue compartments were measured. All animals were asymptomatic postinfection. Although only minimal memory immune responses were detected in peripheral blood, a high frequency of influenza nucleoprotein-specific memory T cells was detected in the lung at the "contraction phase," 49-58 d after second virus inoculation. A substantial proportion of lung nucleoprotein-specific memory CD8(+) T cells expressed CD103 and CD69, phenotypic markers of TRM cells. Lung CD103(+) and CD103(-) memory CD8(+) T cells expressed similar levels of IFN-γ and IL-2. Unlike memory T cells, spontaneous Ab secreting cells and memory B cells specific to influenza hemagglutinin were primarily observed in the mediastinal lymph nodes. Little difference in systemic and local immune responses against influenza was observed between young adult (6-8 y) and old animals (18-28 y). Using a nonhuman primate model, we revealed substantial induction of local T and B cell responses following 2009 pandemic H1N1 infection. Our study identified a subset of influenza-specific lung memory T cells characterized as TRM cells in rhesus monkeys. The rhesus monkey model may be useful to explore the role of TRM cells in local tissue protective immunity after rechallenge and vaccination.


Assuntos
Linfócitos B/imunologia , Memória Imunológica/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Macaca mulatta/imunologia , Infecções por Orthomyxoviridae/imunologia , Linfócitos T/imunologia , Fatores Etários , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos B/metabolismo , Linfócitos B/virologia , Medula Óssea/imunologia , Medula Óssea/metabolismo , Medula Óssea/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Células Cultivadas , Interações Hospedeiro-Patógeno/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Cadeias alfa de Integrinas/imunologia , Cadeias alfa de Integrinas/metabolismo , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-2/imunologia , Interleucina-2/metabolismo , Lectinas Tipo C/imunologia , Lectinas Tipo C/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Linfonodos/imunologia , Linfonodos/metabolismo , Linfonodos/virologia , Macaca mulatta/metabolismo , Macaca mulatta/virologia , Mediastino/virologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Baço/imunologia , Baço/metabolismo , Baço/virologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Fatores de Tempo
7.
J Immunol ; 192(12): 5906-12, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24829418

RESUMO

Although lymphopenia is a hallmark of severe infection with highly pathogenic H5N1 and the newly emerged H7N9 influenza viruses in humans, the mechanism(s) by which lethal H5N1 viruses cause lymphopenia in mammalian hosts remains poorly understood. Because influenza-specific T cell responses are initiated in the lung draining lymph nodes (LNs), and lymphocytes subsequently traffic to the lungs or peripheral circulation, we compared the immune responses in the lung draining LNs postinfection with a lethal A/HK/483/97 or nonlethal A/HK/486/97 (H5N1) virus in a mouse model. We found that lethal H5N1, but not nonlethal H5N1, virus infection in mice enhances Fas ligand (FasL) expression on plasmacytoid dendritic cells (pDCs), resulting in apoptosis of influenza-specific CD8(+) T cells via a Fas-FasL-mediated pathway. We also found that pDCs, but not other DC subsets, preferentially accumulate in the lung draining LNs of lethal H5N1 virus-infected mice, and that the induction of FasL expression on pDCs correlates with high levels of IL-12p40 monomer/homodimer in the lung draining LNs. Our data suggest that one of the mechanisms of lymphopenia associated with lethal H5N1 virus infection involves a deleterious role for pDCs.


Assuntos
Apoptose/imunologia , Células Dendríticas/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Linfopenia/imunologia , Infecções por Orthomyxoviridae/imunologia , Plasmócitos/imunologia , Linfócitos T/imunologia , Animais , Células Dendríticas/patologia , Células Dendríticas/virologia , Proteína Ligante Fas/imunologia , Virus da Influenza A Subtipo H5N1/patogenicidade , Interleucina-12/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Linfopenia/etiologia , Linfopenia/patologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/patologia , Plasmócitos/patologia , Plasmócitos/virologia , Linfócitos T/patologia , Linfócitos T/virologia , Receptor fas/imunologia
8.
J Virol ; 88(14): 8139-52, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24807726

RESUMO

Live attenuated cold-adapted (ca) H5N1, H7N3, H6N1, and H9N2 influenza vaccine viruses replicated in the respiratory tract of mice and ferrets, and 2 doses of vaccines were immunogenic and protected these animals from challenge infection with homologous and heterologous wild-type (wt) viruses of the corresponding subtypes. However, when these vaccine candidates were evaluated in phase I clinical trials, there were inconsistencies between the observations in animal models and in humans. The vaccine viruses did not replicate well and immune responses were variable in humans, even though the study subjects were seronegative with respect to the vaccine viruses before vaccination. Therefore, we sought a model that would better reflect the findings in humans and evaluated African green monkeys (AGMs) as a nonhuman primate model. The distribution of sialic acid (SA) receptors in the respiratory tract of AGMs was similar to that in humans. We evaluated the replication of wt and ca viruses of avian influenza (AI) virus subtypes H5N1, H6N1, H7N3, and H9N2 in the respiratory tract of AGMs. All of the wt viruses replicated efficiently, while replication of the ca vaccine viruses was restricted to the upper respiratory tract. Interestingly, the patterns and sites of virus replication differed among the different subtypes. We also evaluated the immunogenicity and protective efficacy of H5N1, H6N1, H7N3, and H9N2 ca vaccines. Protection from wt virus challenge correlated well with the level of serum neutralizing antibodies. Immune responses were slightly better when vaccine was delivered by both intranasal and intratracheal delivery than when it was delivered intranasally by sprayer. We conclude that live attenuated pandemic influenza virus vaccines replicate similarly in AGMs and human subjects and that AGMs may be a useful model to evaluate the replication of ca vaccine candidates. Importance: Ferrets and mice are commonly used for preclinical evaluation of influenza vaccines. However, we observed significant inconsistencies between observations in humans and in these animal models. We used African green monkeys (AGMs) as a nonhuman primate (NHP) model for a comprehensive and comparative evaluation of pairs of wild-type and pandemic live attenuated influenza virus vaccines (pLAIV) representing four subtypes of avian influenza viruses and found that pLAIVs replicate similarly in AGMs and humans and that AGMs can be useful for evaluation of the protective efficacy of pLAIV.


Assuntos
Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Doenças dos Primatas/prevenção & controle , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana , Masculino , Camundongos , Infecções por Orthomyxoviridae/imunologia , Pandemias , Doenças dos Primatas/imunologia , Sistema Respiratório/virologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
9.
J Immunol ; 190(11): 5659-65, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23616574

RESUMO

Ab-dependent enhancement (ADE) of dengue virus (DENV) infection is mediated through the interaction of viral immune complexes with FcγRs, with notable efficiency of FcγRII. Most human dengue target cells coexpress activating (FcγRIIa) and inhibitory (FcγRIIb) isoforms, but their relative roles in ADE are not well understood. We studied the effects of FcγRIIa and FcγRIIb by transfecting cells to express each individual receptor isoform or through coexpression of both isoforms. We showed that although both isoforms similarly bind dengue-immune complexes, FcγRIIa efficiently internalized virus leading to productive cellular infection, unlike FcγRIIb. We next focused on the main discriminating feature of these isoforms: their distinct intracytoplasmic tails (FcγRIIa with an immunoreceptor tyrosine-based activation motif [ITAM] and FcγRIIb with an immunoreceptor tyrosine-based inhibitory motif [ITIM]). We engineered cells to express "swapped" versions of their FcγRII by switching the cytoplasmic tails containing the ITAM/ITIM motifs, leaving the remainder of the receptor intact. Our data show that both FcγRIIa and FcγRIIb comparably bind dengue immune complexes. However, wild type FcγRIIa facilitates DENV entry by virtue of the ITAM motif, whereas the swapped version FcγRIIa-ITIM significantly inhibited ADE. Similarly, replacing the inhibitory motif in FcγRIIb with an ITAM (FcγRIIb-ITAM) reconstituted ADE capacity to levels of the wild type activating counterpart, FcγRIIa. Our data suggest that FcγRIIa and FcγRIIb isoforms, as the most abundantly distributed class II Fcγ receptors, differentially influence Ab-mediated DENV infection under ADE conditions both at the level of cellular infection and viral production.


Assuntos
Anticorpos/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Domínios e Motivos de Interação entre Proteínas/imunologia , Receptores de IgG/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Complexo Antígeno-Anticorpo/imunologia , Complexo Antígeno-Anticorpo/metabolismo , Linhagem Celular , Dengue/metabolismo , Humanos , Células K562 , Camundongos , Dados de Sequência Molecular , Células NIH 3T3 , Isoformas de Proteínas , Receptores de IgG/genética , Receptores de IgG/metabolismo , Transfecção
10.
Artigo em Inglês | MEDLINE | ID: mdl-26513923

RESUMO

Screening for densoviruses (DNVs) from Aedes, Culex and Toxorhynchites mosquitoes collected in Bangkok and surrounding regions identified two clades of Aedes DNV; Ae. aegypti DNV (AaeDNV) and Ae. albopictus DNV (AalDNV) by PCR-restriction fragment length polymorphism (PCR-RFLP). From nucleotide sequencing and phylogenetic analysis of PCR amplicons of a fragment of DNV capsid gene, these DNVs were shown to be new DNV genetic variations similar to AaeDNV. Isolation and identification of densoviruses from indigenous field mosquitoes reside in natural habitat should be helpful in monitoring the distribution of DNVs in important mosquitoes, especially Ae. aegypti and Ae. albopictus, vector for dengue and yellow fever viruses.


Assuntos
Aedes/virologia , Culex/virologia , DNA Viral/análise , Densovirus/genética , Variação Genética , Animais , Sequência de Bases , Culicidae/virologia , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Tailândia
11.
Artigo em Inglês | MEDLINE | ID: mdl-25427347

RESUMO

Two clades of Aedes densovirus, Aedes aegypti densovirus and Aedes albopictus densovirus, were classified according to the origin of isolation. These two densoviruses were isolated from indigenous mosquitoes and mosquito cell lines, respectively. This group of invertebrate viruses belongs to the subfamily Densovirinae of the Parvoviridae family and infects only insects. Several types of densoviruses have been isolated from mosquitoes especially Aedes aegypti and Aedes albopictus, which are important vectors of dengue hemorrhagic fever and yellow fever in humans. We describe applications of post-PCR techniques, re- striction fragment length polymorphism (RFLP) and single-strand conformation polymorphism (SSCP) to classify these two clades of Aedes densoviruses isolated from different origins. These methods are simple and rapid and are applicable to identify other groups of densoviruses isolated from biological samples.


Assuntos
Aedes/virologia , Densovirus/genética , Insetos Vetores/virologia , Animais , Culicidae/virologia , Genoma Viral , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples
12.
J Acquir Immune Defic Syndr ; 93(3): 251-259, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36881814

RESUMO

INTRODUCTION: Data regarding the immunogenicity of a quadrivalent inactivated influenza vaccine (IIV4) among persons with HIV with different levels of CD4 cell count are limited. Here, we report the immunogenicity of IIV4 in persons with HIV with different CD4 cell count levels by determining seroprotection (SP) and seroconversion rate after vaccination. METHOD: Persons with HIV were prospectively recruited to receive IIV4 (season 2021) between November 2021 and January 2022. Hemagglutination inhibition titers were assessed before and at 28 days after vaccination and classified as SP or seroconversion with comparison of characteristic between CD4 cell count >350 cells/mm 3 group and CD4 cell count ≤350 cells/mm 3 . RESULT: A total of 70 persons with HIV received the IIV4. The mean (SD) age was 48 (9) years, and 64% were men. Most of them (74%) were maintained on a nonnucleoside reverse transcriptase inhibitor-based regimen with an undetectable HIV viral load (100%). There was a significantly greater proportion of persons with HIV who achieved SP against A/Hong Kong/2571/2019-like virus (H3N2) variant in those with CD4 cell count >350 cells/mm 3 compared with those with CD4 cell count ≤350 cells/mm 3 (98.3% vs. 72.3%), relative risk 1.35 (95% confidence interval: 1.13 to 1.61, P = 0.011). Furthermore, the participants with CD4 cell count >350 cells/mm 3 were significantly more likely to achieve SP against B/Phuket/287/2013 strain (98.3% vs. 72.3%, relative risk 1.35; 95% confidence interval: 1.13 to 1.61, P = 0.011). CONCLUSION: Persons with HIV with greater CD4 cell count could achieve a higher chance of SP against B/Phuket/287/2013 and A/Hong Kong/2571/2019-like virus (H3N2) strains after IIV4 vaccination. Therefore, new strategies should be investigated and offered to those with low CD4 cell counts.


Assuntos
Infecções por HIV , Soropositividade para HIV , Vacinas contra Influenza , Influenza Humana , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Vírus da Influenza A Subtipo H3N2 , Estudos Prospectivos , Anticorpos Antivirais , Método Duplo-Cego , Influenza Humana/prevenção & controle , Vacinas de Produtos Inativados , Contagem de Linfócito CD4
13.
Vet World ; 16(11): 2366-2373, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38152266

RESUMO

Background and Aims: Asthma, a chronic disease affecting humans and animals, has recently become increasingly prevalent and steadily widespread. The alternative treatment of asthma using helminth infections or helminth-derived immunomodulatory molecules (IMs) has been evaluated and demonstrated significant amelioration of disease severity index in vitro and in vivo. Trichinella spiralis, a parasitic nematode and its IMs, elicits a potential to relieve asthma and other immune-related disorders. In this study, we investigated the immunomodulatory function of recombinant T. spiralis novel cystatin (rTsCstN) in ameliorating acute inflammatory asthma disorders in a murine model. Materials and Methods: Female BALB/c mice were sensitized using intraperitoneal injection of ovalbumin (OVA)/alum and subsequently challenged with intranasal administration of OVA alone or OVA + rTsCstN for 3 consecutive days, producing OVA-induced allergic asthma models. To evaluate the therapeutic efficacy of rTsCstN, the inflammatory cells and cytokines in bronchoalveolar lavage fluid (BALF) and OVA-specific immunoglobulin E levels in serum were assessed. Histological alterations in the lung tissues were determined by hematoxylin and eosin (H&E) staining and eventually scored for the extent of inflammatory cell infiltration. Results: The asthmatic mouse models challenged with OVA + rTsCstN demonstrated a significant reduction of eosinophils (p < 0.01), macrophages (p < 0.05), and cytokines tumor necrosis factor-α (p < 0.05) and interferon (IFN)-γ (p < 0.05) in BALF when compared with the mice challenged with OVA alone. However, the levels of interleukin (IL)-4 and IL-10 remained unchanged. Histological examination revealed that mice administered OVA + rTsCstN were less likely to have inflammatory cell infiltration in their perivascular and peribronchial lung tissues than those administered OVA alone. Conclusion: Recombinant T. spiralis novel cystatin demonstrated immunomodulatory effects to reduce severe pathogenic alterations in asthma mouse models, encouraging a viable alternative treatment for asthma and other immunoregulatory disorders in humans and animals in the future.

14.
Viruses ; 15(5)2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37243211

RESUMO

Japanese encephalitis virus (JEV) is a member of the Flaviviridae family and one of Asia's most common causes of encephalitis. JEV is a zoonotic virus that is transmitted to humans through the bite of infected mosquitoes of the Culex species. While humans are dead-end hosts for the virus, domestic animals such as pigs and birds are amplification hosts. Although JEV naturally infected monkeys have been reported in Asia, the role of non-human primates (NHPs) in the JEV transmission cycle has not been intensively investigated. In this study, we demonstrated neutralizing antibodies against JEV in NHPs (Macaca fascicularis) and humans living in proximity in two provinces located in western and eastern Thailand by using Plaque Reduction Neutralization Test (PRNT). We found a 14.7% and 5.6% seropositive rate in monkeys and 43.7% and 45.2% seropositive rate in humans living in west and east Thailand, respectively. This study observed a higher seropositivity rate in the older age group in humans. The presence of JEV neutralizing antibodies in NHPs that live in proximity to humans shows the occurrence of natural JEV infection, suggesting the endemic transmission of this virus in NHPs. According to the One Health concept, regular serological studies should be conducted especially at the animal-human interface.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Humanos , Animais , Suínos , Idoso , Tailândia/epidemiologia , Haplorrinos , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/veterinária , Anticorpos Neutralizantes , Anticorpos Antivirais
15.
Hum Vaccin Immunother ; 19(2): 2228670, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37439770

RESUMO

This open-labeled non-inferiority trial evaluated immunogenicity and reactogenicity of heterologous and homologous COVID-19 vaccination schedules in pregnant Thai women. 18-45-year-old pregnant women with no history of COVID-19 infection or vaccination and a gestational age of ≥12 weeks were randomized 1:1:1 into three two-dose primary series scheduled 4 weeks apart: BNT162b2-BNT162b2 (Group 1), ChAdOx1-BNT162b2 (Group 2), and CoronaVac-BNT162b2 (Group 3). Serum antibody responses, maternal and cord blood antibody levels at delivery, and adverse events (AEs) following vaccination until delivery were assessed. The 124 enrolled participants had a median age of 31 (interquartile range [IQR] 26.0-35.5) years and gestational age of 23.5 (IQR 18.0-30.0) weeks. No significant difference in anti-receptor binding domain (RBD) IgG were observed across arms at 2 weeks after the second dose. Neutralizing antibody geometric mean titers against the ancestral Wuhan strain were highest in Group 3 (258.22, 95% CI [187.53, 355.56]), followed by Groups 1 (187.47, 95% CI [135.15, 260.03]) and 2 (166.63, 95% CI [124.60, 222.84]). Cord blood anti-RBD IgG was correlated with, and equal to or higher than, maternal levels at delivery (r = 0.719, P < .001) and inversely correlated with elapsed time after the second vaccination (r = -0.366, P < .001). No significant difference in cord blood antibody levels between groups were observed. Local and systemic AEs were mild-to-moderate and more frequent in Group 2. Heterologous schedules of CoronaVac-BNT162b2 or ChAdOx1-BNT162b2 induced immunogenicity on-par with BNT162b2-BNT162b2 and may be considered as alternative schedules for primary series in pregnant women in mRNA-limited vaccine settings.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Complicações Infecciosas na Gravidez , Adolescente , Adulto , Feminino , Humanos , Lactente , Pessoa de Meia-Idade , Gravidez , Adulto Jovem , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Imunogenicidade da Vacina , Imunoglobulina G , Complicações Infecciosas na Gravidez/prevenção & controle , Gestantes , Vacinação
16.
Viruses ; 15(6)2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37376670

RESUMO

Metagenomics has demonstrated its capability in outbreak investigations and pathogen surveillance and discovery. With high-throughput and effective bioinformatics, many disease-causing agents, as well as novel viruses of humans and animals, have been identified using metagenomic analysis. In this study, a VIDISCA metagenomics workflow was used to identify potential unknown viruses in 33 fecal samples from asymptomatic long-tailed macaques (Macaca fascicularis) in Ratchaburi Province, Thailand. Putatively novel astroviruses, enteroviruses, and adenoviruses were detected and confirmed by PCR analysis of long-tailed macaque fecal samples collected from areas in four provinces, Ratchaburi, Kanchanaburi, Lopburi, and Prachuap Khiri Khan, where humans and monkeys live in proximity (total n = 187). Astroviruses, enteroviruses, and adenoviruses were present in 3.2%, 7.5%, and 4.8% of macaque fecal samples, respectively. One adenovirus, named AdV-RBR-6-3, was successfully isolated in human cell culture. Whole-genome analysis suggested that it is a new member of the species Human adenovirus G, closely related to Rhesus adenovirus 53, with evidence of genetic recombination and variation in the hexon, fiber, and CR1 genes. Sero-surveillance showed neutralizing antibodies against AdV-RBR-6-3 in 2.9% and 11.2% of monkeys and humans, respectively, suggesting cross-species infection of monkeys and humans. Overall, we reported the use of metagenomics to screen for possible new viruses, as well as the isolation and molecular and serological characterization of the new adenovirus with cross-species transmission potential. The findings emphasize that zoonotic surveillance is important and should be continued, especially in areas where humans and animals interact, to predict and prevent the threat of emerging zoonotic pathogens.


Assuntos
Infecções por Adenoviridae , Adenovirus dos Símios , Infecções por Enterovirus , Enterovirus , Animais , Humanos , Macaca fascicularis , Adenovirus dos Símios/genética , Tailândia/epidemiologia , Macaca mulatta , Adenoviridae , Infecções por Adenoviridae/veterinária , Fezes , Filogenia
17.
Viruses ; 15(9)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37766380

RESUMO

After publication of the article, the authors received comments from a member of the Viruses editorial board who is an expert in the field of adenovirus concerning figures and references that should be included in the paper [...].

18.
Vaccines (Basel) ; 11(9)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37766091

RESUMO

Many patients develop post-acute COVID syndrome (long COVID (LC)). We compared the immune response of LC and individuals with post-COVID full recovery (HC) during the Omicron pandemic. Two hundred ninety-two patients with confirmed COVID infections from January to May 2022 were enrolled. We observed anti-SARS-CoV-2 receptor-binding domain immunoglobulin G, surrogate virus neutralization test, T cell subsets, and neutralizing antibodies against Wuhan, BA.1, and BA.5 viruses (NeuT). NeuT was markedly reduced against BA.1 and BA.5 in HC and LC groups, while antibodies were more sustained with three doses and an updated booster shot than ≤2-dose vaccinations. The viral neutralization ability declined at >84-days after COVID-19 onset (PC) in both groups. PD1-expressed central and effector memory CD4+ T cells, and central memory CD8+ T cells were reduced in the first months PC in LC. Therefore, booster vaccines may be required sooner after the most recent infection to rescue T cell function for people with symptomatic LC.

19.
J Virol ; 85(4): 1671-83, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21123382

RESUMO

Antibody-dependent enhancement (ADE) is implicated in severe, usually secondary, dengue virus (DV) infections. Preexisting heterotypic antibodies, via their Fc-gamma receptor (FcγR) interactions, may increase disease severity through enhanced target cell infection. Greater numbers of infected target cells may contribute to higher viremia and excess cytokine levels often observed in severe disease. Monocytes, macrophages, and immature and mature dendritic cells (DC) are considered major cellular targets of DV. Apheresis of multiple donors allowed isolation of autologous primary myeloid target cell types for head-to-head comparison of infection rates, viral output, and cytokine production under direct infection (without antibody) or ADE conditions (with antibody). All studied cell types except immature DC supported ADE. All cells undergoing ADE secreted proinflammatory cytokines (interleukin-6 [IL-6] and tumor necrosis factor alpha [TNF-α]) at enhancement titers, but distinct cell-type-specific patterns were observed for other relevant proteins (alpha/beta interferon [IFN-α/ß] and IL-10). Macrophages produced type I interferons (IFN-α/ß) that were modulated by ADE. Mature DC mainly secreted IFN-ß. Interestingly, only monocytes secreted IL-10, and only upon antibody-enhanced infection. While ADE infection rates were remarkably consistent in monocytes (10 to 15%) across donors, IL-10 protein levels varied according to previously described regulatory single nucleotide polymorphisms (SNPs) in the IL-10 promoter region. The homozygous GCC haplotype was associated with high-level IL-10 secretion, while the ACC and ATA haplotypes produced intermediate and low levels of IL-10, respectively. Our data suggest that ADE effects are cell type specific, are influenced by host genetics, and, depending on relative infection rates, may further contribute to the complexity of DV pathogenesis.


Assuntos
Anticorpos Facilitadores/imunologia , Vírus da Dengue/patogenicidade , Interleucina-10/genética , Fagócitos/citologia , Polimorfismo Genético , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Anticorpos Facilitadores/genética , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Dengue/imunologia , Dengue/fisiopatologia , Dengue/virologia , Vírus da Dengue/imunologia , Vírus da Dengue/fisiologia , Humanos , Interleucina-10/imunologia , Interleucina-10/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/virologia , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/virologia , Fagócitos/classificação , Regiões Promotoras Genéticas/genética , Replicação Viral
20.
One Health ; 15: 100455, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36532673

RESUMO

Chikungunya virus (CHIKV) and Zika virus (ZIKV) are mosquito-borne viruses that have caused several outbreaks worldwide. Aedes mosquitoes transmit these viruses mainly through sylvatic and urban transmission cycles. In the sylvatic cycle, nonhuman primates (NHPs) can be infected with CHIKV and ZIKV and may play an essential role as reservoirs for virus transmission. To improve our knowledge on the role of NHPs in the sylvatic cycle, we performed a systematic review and meta-analysis study on the seroprevalence of CHIKV and ZIKV worldwide in NHPs. According to the PRISMA guidelines, 17 CHIKV and 16 ZIKV seroprevalence studies in NHPs from 3 online databases: PubMed, Embase, and Scopus were selected. Data were extracted, including location and study year, type of NHP, sample size, serological tests, and seropositivity. All included studies have high-quality scores, between 5 and 8, corresponding to the grading criteria. Seroprevalence estimation was pooled using the 'meta' package in the R statistical software. The estimated pooled seroprevalence of CHIKV and ZIKV in NHP was 17% (95%CI: 5-34, I2: 99%, p < 0.05) and 6% (95% CI: 2-12, I 2 : 92%, p < 0.05), respectively. Most of the NHPs tested were wild Old World monkeys. The subgroup was analyzed by continents; high seropositive CHIKV and ZIKV were found in African NHPs at 35% (95% CI 9-66.0, I 2  = 100) and 16% (95% CI 1-44, I 2  = 97), respectively. While NHPs in America have 7% (95% CI 0-28, I 2 = 99) and 2% (95% CI 1-3, I 2 = 54) against CHIKV and ZIKV. In Asia, 6% (95% CI: 5-34, I 2  = 96) CHIKV seroprevalence and 7% (95% CI 0-20, I 2  = 98) ZIKV seroprevalence were found in NHP. This study provides a comprehensive overview of the seroprevalence of CHIKV and ZIKV among NHPs in various regions.

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