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1.
ACS Appl Mater Interfaces ; 15(26): 31159-31172, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37319124

RESUMO

Integrating nucleic acid extraction in amplification-based point-of-care diagnostics will be a significant feature for next-generation point-of-care virus detection devices. However, extracting DNA efficiently on a microfluidic chip poses many technological and commercialization challenges, including manual steps, multiple instruments, pretreatment processes, and the use of organic solvents (ethanol, IPA) that inhibit detection, which is not viable with routine testing such as viral load monitoring of transplant patients for post-operative care. This paper presents a microfluidic system capable of two-step DNA extraction from blood using a UV-assisted hyperbranched poly(ß-amino ester) (HPAE)-modified silica membrane for cytomegalovirus (CMV) detection in a rapid and instrument-free manner without the presence of amplification inhibitors. HPAEs of varying branch ratios were synthesized, screened, and coated on a silica membrane and bonded between two layers of poly(methyl methacrylate) (PMMA) substrates. Our system could selectively extract DNA from blood with an efficiency of 94% and a lower limit viral load of 300 IU/mL in 20 min. The extracted DNA was used as the template for real-time loop-mediated isothermal amplification (LAMP)-based detection of CMV and was found to produce a fluorescent signal intensity that was comparable with commercially extracted templates. This system can be integrated easily with a nucleic acid amplification system and used for routine rapid testing of viral load in patient blood samples.


Assuntos
Infecções por Citomegalovirus , Técnicas Analíticas Microfluídicas , Ácidos Nucleicos , Humanos , Microfluídica , DNA , Técnicas de Amplificação de Ácido Nucleico
2.
Viral Immunol ; 36(1): 63-70, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648773

RESUMO

Understanding the functional characteristics of antibodies produced against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) will assist in the determination of disease outcomes for this virus. In this study, the ability of antibodies to inhibit viral entry into the host cell through the interaction of the receptor binding domain of the viral spike protein and the angiotensin-converting enzyme 2 receptor on the human cell surface was investigated. The SARS-CoV-2 IgG levels in 20 SARS-CoV-2 positive patients were measured using an enzyme-linked immunosorbent assay, and the samples were further analyzed using a functional binding assay. Inhibition of viral infectivity was also measured using a pseudovirus neutralization assay against a D614G SARS-CoV-2 virus strain. A significant correlation between IgG levels and neutralizing antibody 50% inhibitory concentration (IC50) titers was observed (p < 0.05). Similarly, the IC50 titers obtained in the neutralization and binding assays were significantly correlated (p < 0.001). Varying levels of IgG and IC50 titers were observed for the SARS-CoV-2 antibody-positive samples, with one sample not showing any neutralizing capability despite detectable IgG levels. Gender comparisons showed no statistical differences in any of the assays. These results suggest that increased SARS-CoV-2 IgG levels correlate with greater protection against the entry of the virus into cells; however, further investigations in larger studies are needed to confirm the correlates of protection.


Assuntos
COVID-19 , Humanos , Enzima de Conversão de Angiotensina 2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunoglobulina G , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química
3.
J Clin Virol ; 157: 105296, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36209622

RESUMO

BACKGROUND: Despite widespread use of the mumps vaccine resulting in significant reduction in the incidence of symptomatic mumps infection, large outbreaks continue to occur in highly vaccinated populations. OBJECTIVES: We examined the mumps-specific IgG, IgG subclasses and neutralization titres to the outbreak Genotype G5 and Jeryl Lynn vaccine (Genotype A) mumps strains. STUDY DESIGN: Sera from 207 individuals were classified into five distinct cohorts: healthy controls and mumps cases of 5-17 years and 18-25 years, and naturally infected individuals of 50+ years. Mumps specific IgG and IgG subclass levels were measured using modified ELISA assays with lysates and nucleoprotein antigens from both the mumps vaccine and circulating Genotype G5 strains. All sera were investigated for in vitro neutralizing antibody titres (GMT) using focus reduction neutralization assays. Data was analysed using the Kruskal-Wallis test and pairwise Wilcoxon tests. RESULTS: Mumps cases had higher mumps IgG levels compared to controls, to both the vaccine and outbreak strains, however levels decreased with age. Mumps IgG3 levels were significantly raised in mumps cases (p < 0.001). Neutralization titres were lower to the outbreak strain in all cohorts with titres markedly lower in the mumps cohorts compared to healthy controls. Mean GMT to the vaccine strain increased with age. The naturally infected group displayed the highest GMT to the JL vaccine and the lowest GMT to the outbreak strain. CONCLUSIONS: Antigenic differences between mumps vaccine strain and circulating mumps viruses decrease the cross-neutralization capacity of vaccine-induced antibodies which may play a role in breakthrough infection.


Assuntos
Caxumba , Humanos , Caxumba/epidemiologia , Caxumba/prevenção & controle , Vírus da Caxumba/genética , Vacina contra Caxumba , Anticorpos Antivirais , Testes de Neutralização , Imunoglobulina G , Surtos de Doenças
4.
Nano Lett ; 21(24): 10149-10156, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34881894

RESUMO

Direct contact with contaminated surfaces in frequently accessed areas is a confirmed transmission mode of SARS-CoV-2. To address this challenge, we have developed novel plastic films with enhanced effectiveness for deactivating the SARS-CoV-2 by means of nanomaterials combined with nanopatterns. Results prove that these functionalized films are able to deactivate SARS-CoV-2 by up to 2 orders of magnitude within the first hour compared to untreated films, thus reducing the likelihood of transmission. Nanopatterns can enhance the antiviral effectiveness by increasing the contact area between nanoparticles and virus. Significantly, the established process also considers the issue of scalability for mass manufacturing. A low-cost process for nanostructured antiviral films integrating ultrasonic atomization spray coating and thermal nanoimprinting lithography is proposed. A further in-depth investigation should consider the size, spacing, and shape of nanopillars, the type and concentration of nanoparticles, and the scale-up and integration of these processes with manufacturing for optimal antiviral effectiveness.


Assuntos
COVID-19 , Nanoestruturas , Antivirais/farmacologia , Humanos , Plásticos , SARS-CoV-2
5.
Front Immunol ; 11: 2089, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072071

RESUMO

History illustrates the remarkable public health impact of mass vaccination, by dramatically improving life expectancy and reducing the burden of infectious diseases and co-morbidities worldwide. It has been perceived that if an individual adhered to the MMR vaccine schedule that immunity to mumps virus (MuV) would be lifelong. Recent mumps outbreaks in individuals who had received two doses of the Measles Mumps Rubella (MMR) vaccine has challenged the efficacy of the MMR vaccine. However, clinical symptoms, complications, viral shedding and transmission associated with mumps infection has been shown to be reduced in vaccinated individuals, demonstrating a benefit of this vaccine. Therefore, the question of what constitutes a good mumps vaccine and how its impact is assessed in this modern era remains to be addressed. Epidemiology of the individuals most affected by the outbreaks (predominantly young adults) and variance in the circulating MuV genotype have been well-described alluding to a collection of influences such as vaccine hesitancy, heterogeneous vaccine uptake, primary, and/or secondary vaccine failures. This review aims to discuss in detail the interplay of factors thought to be contributing to the current mumps outbreaks seen in highly vaccinated populations. In addition, how mumps diagnoses has progressed and impacted the understanding of mumps infection since a mumps vaccine was first developed, the limitations of current laboratory tests in confirming protection in vaccinated individuals and how vaccine effectiveness is quantified are also considered. By highlighting knowledge gaps within this area, this state-of-the-art review proposes a change of perspective regarding the impact of a vaccine in a highly vaccinated population from a clinical, diagnostic and public perspective, highlighting a need for a paradigm shift on what is considered vaccine immunity.


Assuntos
Surtos de Doenças/prevenção & controle , Vacina contra Sarampo-Caxumba-Rubéola , Caxumba , Vacinação , Humanos , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Vacina contra Sarampo-Caxumba-Rubéola/uso terapêutico , Caxumba/epidemiologia , Caxumba/imunologia , Caxumba/prevenção & controle
6.
J Clin Virol ; 129: 104517, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32629188

RESUMO

BACKGROUND: Mumps outbreaks continue to occur in highly vaccinated populations. Although the diagnosis of mumps is primarily based on clinical symptoms, other viral infections such as parainfluenza can manifest in a similar manner. Therefore, laboratory confirmation of mumps virus infection is important. OBJECTIVES: The aims of this study were to examine mumps cases during the January 2018 to March 2019 period in Ireland as well as to evaluate the association between mumps RNA viral loads, mumps IgG levels, age and gender among patients with laboratory-confirmed mumps virus infection. STUDY DESIGN: Oral fluid samples requested for mumps RNA testing (n = 1296) were included in the study. The mumps N gene was detected by real time PCR and reported as Ct values. RESULTS: The proportion of samples received monthly with detectable mumps RNA increased from 10.26%-70.3% during the recent outbreak. Acute mumps cases occurred predominantly in the 16-25 years old age cohort (67.5 %) and in males (55.9 %). Mumps RNA viral loads were significantly higher in females (p < 0.001). During the outbreak, a significantly higher proportion of samples had Ct <30 (p < 0.05). A significant correlation was observed between mumps IgG levels and Ct values in oral fluid samples (p < 0.0001). CONCLUSIONS: The presence of low mumps virus-specific IgG in oral fluids is significantly associated with high mumps viral loads. Our findings show that mumps virus is maintained in circulation in the non-outbreak period and acute mumps cases occur predominantly in the MMR vaccinated young adult male population.


Assuntos
Caxumba , Adolescente , Adulto , Anticorpos Antivirais , Surtos de Doenças , Feminino , Humanos , Imunoglobulina G , Masculino , Vacina contra Sarampo-Caxumba-Rubéola , Caxumba/epidemiologia , Vírus da Caxumba/imunologia , Carga Viral , Adulto Jovem
7.
Int J Ophthalmol ; 12(9): 1493-1497, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31544048

RESUMO

This study sought to identify potential therapeutic targets in herpes simplex keratitis (HSK) patients with active and inactive infection by investigating peripheral cytokine production. Peripheral blood mononuclear cells (PBMCs) and serum were prepared from healthy controls and HSK patients during active infection or following treatment (inactive infection). Serum antibody titres were determined by ELISA. Protein expression levels were analysed by Western blot. Cytokine levels were determined by multiplex ELISA. Active corneal herpes simplex virus type 1 (HSV-1) infection resulted in significantly elevated peripheral levels of IL-1ß in HSK patients compared to healthy controls, and remained significantly increased following treatment. Elevated production of IL-1ß in inactive patients was associated with significantly increased levels of IRF3 and STAT1, key proteins involved in promoting anti-viral immune responses. Our data suggest that inflammation persists beyond the period that it is clinically evident and that enhanced peripheral production of IL-1ß may have implications for HSV-1 viral clearance in active and inactive HSK patients.

8.
Med Microbiol Immunol ; 208(5): 693-702, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30859301

RESUMO

The suitability of routine diagnostic HIV assays to accurately discriminate between recent and non-recent HIV infections has not been fully investigated. The aim of this study was to compare an established HIV recency assay, the Sedia limiting antigen HIV avidity assay (LAg), with the diagnostic assays; Abbott ARCHITECT HIV Ag/Ab Combo and INNO-LIA HIV line assays. Samples from all new HIV diagnoses in Ireland from January to December 2016 (n = 455) were tested. An extended logistic regression model, the Spiegelhalter-Knill-Jones method, was utilised to establish a scoring system to predict recency of HIV infection. As proof of concept, 50 well-characterised samples were obtained from the CEPHIA repository whose stage of infection was blinded to the authors, which were tested and analysed. The proportion of samples that were determined as recent was 18.1% for LAg, 6.4% with the ARCHITECT, and 14.5% in the INNO-LIA assay. There was a significant correlation between the ARCHITECT S/CO values and the LAg results, r = 0.717, p < 0.001. ROC analysis revealed that an ARCHITECT S/CO < 250 had a sensitivity and specificity of 90.32% and 89.83%, respectively. Combining the Abbott ARCHITECT HIV Ag/Ab Combo assay and INNO-LIA HIV assays resulted in an observed risk of being recent of 100%. Analysis of the CEPHIA samples revealed a strong agreement between the LAg assay and the combination of routine assays (κ = 0.908, p < 0.001). Our findings provide evidence that assays routinely employed to diagnose and confirm HIV infection may be utilised to determine the recency of HIV infection.


Assuntos
Afinidade de Anticorpos , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , Testes Sorológicos/métodos , Irlanda , Curva ROC , Sensibilidade e Especificidade
9.
J Nephrol ; 31(3): 445-451, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29185211

RESUMO

BACKGROUND: Epstein-Barr virus (EBV) was the first human virus identified to express microRNA (miRNA). To date, 44 mature miRNAs are encoded for within the EBV genome. EBV miRNAs have not been profiled in paediatric renal transplant recipients. In this study, we investigated circulating EBV miRNA profiles as novel biomarkers in paediatric renal transplant patients. METHODS: Forty-two microRNAs encoded within 2 EBV open reading frames (BART and BHRF) were examined in renal transplant recipients who resolved EBV infection (REI) or maintained chronic high viral loads (CHL), and in non-transplant patients with acute infectious mononucleosis (IM). RESULTS: Plasma EBV-miR-BART2-5p was present in higher numbers of IM (7/8) and CHL (7/10) compared to REI (7/12) patients. A trend was observed between the numbers of plasma EBV miRNAs expressed and EBV viral load (p < 0.07). Several EBV-miRs including BART7-3p, 15, 9-3p, 11-3p, 1-3p and 3-3p were detected in IM and CHL patients only. The lytic EBV-miRs, BHRF1-2-3p and 1-1, indicating active viral replication, were detected in IM patients only. One CHL patient developed post-transplant lymphoproliferative disease (PTLD) after several years and analysis of 10 samples over a 30-month period showed an average 24-fold higher change in plasma EBV-miR-BART2-5p compared to the CHL group and 110-fold higher change compared to the REI group. CONCLUSIONS: Our results suggest that EBV-miR-BART2-5p, which targets the stress-induced immune ligand MICB to escape recognition and elimination by NK cells, may have a role in sustaining high EBV viral loads in CHL paediatric kidney transplant recipients.


Assuntos
Herpesvirus Humano 4/genética , Mononucleose Infecciosa/sangue , Transplante de Rim , MicroRNAs/sangue , RNA Viral/sangue , Carga Viral/genética , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
11.
Medicine (Baltimore) ; 95(6): e2735, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26871815

RESUMO

Cytomegalovirus (CMV) infections occur worldwide and primary infection usually occurs in early childhood and is often asymptomatic whereas primary infection in adults may result in symptomatic illness. CMV establishes a chronic latent infection with intermittent periods of reactivation. Primary infection or reactivation associate with increased mortality and morbidity in those who are immunocompromised. Transplacental transmission may result in significant birth defects or long-term sensorineural hearing loss.We performed a study to determine the CMV seroprevalence and the association between HLA Class I alleles and frequency of CMV infection in Ireland. The presence of CMV IgG, a marker of previous CMV infection, was determined for a cohort of 1849 HLA typed solid organ transplant donors between 1990 and 2013. The presence of CMV IgG was correlated with HLA type.The CMV seroprevalence in solid organ transplant donors was 33.4% (range 22-48% per annum) over the time period 1990 to 2013. Multivariate logistic regression analysis showed that both age and HLA alleles were associated with CMV seropositivity. A significant and positive relationship between age and CMV seropositivity was observed (OR = 1.013, P < 0.001, CI [1.007, 1.019]). Chi-square analysis revealed that the female gender was independently associated with CMV seropositivity (P < 0.01). Seroprevalence in women of reproductive age (20-39 years) was significantly higher than men of the same age (37% vs 26%, P < 0.01). The frequencies of HLA-A1, HLA-A2, and HLA-A3 in our cohort were 40.8%, 48.8%, and 25.9%, respectively. Logistic regression analysis showed that the presence of HLA-A1 but not HLA-A2 or HLA-A3 was independently associated with CMV seronegativity (P < 0.01). Interestingly, individuals who co-expressed HLA-A2 and HLA-A3 alleles were significantly more likely to be CMV seropositive (P < 0.02). The frequencies of HLA-B5, HLA-B7, and HLA-B8 in our cohort were 6.1%, 31.2%, and 30.8%, respectively. The presence of the most common inherited haplotype in the Irish population, HLA-A1, B8 was significantly associated with CMV seronegativity (OR = 1.278, P < 0.001, CI [1.049, 1.556]).CMV seroprevalence is lower in Ireland compared with other countries. The high frequency of HLA-A1 in the Irish population may, in part, have a role in the reduced susceptibility to CMV infection.


Assuntos
Infecções por Citomegalovirus/epidemiologia , Antígenos HLA-A/sangue , Antígenos HLA-B/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Criança , Estudos de Coortes , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/imunologia , Feminino , Frequência do Gene , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Haplótipos , Humanos , Irlanda/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
12.
J Clin Virol ; 74: 8-12, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26630067

RESUMO

BACKGROUND: Mumps outbreaks continue to occur globally, despite high levels of uptake of the mumps vaccine. OBJECTIVES: In order to address immunity to the current circulating wildtype virus, we sought to determine a mumps G5 specific IgG quantitative value which correlates with genotype G5 specific neutralization ability in vitro. STUDY DESIGN: Sera from 199 individuals including controls and acute mumps cases were assessed for mumps specific IgG titres using five different enzyme immunoassays coated with antigen from different mumps virus strains. A subset of 66 sera was also assessed for in vitro neutralizing antibody against a contemporary circulating genotype G5 mumps virus. RESULTS: For all the different antigenic targets, mumps specific IgG titres were higher in patients following acute mumps infection compared to controls. In acute mumps infected patients, females showed significantly higher serum titres of anti-G5 IgG compared to males (p<0.05). Furthermore, control males did not show any change in G5 specific IgG with increasing age whereas females show a progressive rise in titre. Linear regression analysis revealed a significant association between the mumps G5 specific IgG levels in the EIA and the in vitro neutralization titres (r(2)=0.59). CONCLUSIONS: Specific IgG to the current circulating genotype G5 mumps strain showed significantly lower titres in males which supports our previous observation that there is a male gender bias in cases of acute mumps infection. Furthermore, in this preliminary study, the data indicate that genotype G5 specific IgG levels of >40 RU/ml are required for neutralization capability to be observed in vitro.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Surtos de Doenças , Genótipo , Vírus da Caxumba/imunologia , Caxumba/epidemiologia , Caxumba/virologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Caxumba/imunologia , Vírus da Caxumba/classificação , Vírus da Caxumba/genética , Vírus da Caxumba/isolamento & purificação , Adulto Jovem
13.
J Clin Virol ; 60(4): 374-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24929750

RESUMO

BACKGROUND: Ireland is classified as an area of high measles incidence. A World Health Organisation-European Region strategic plan exists for measles elimination by 2015. OBJECTIVES: To retrospectively investigate measles outbreaks using all patient samples (sera and oral fluid) received for measles laboratory diagnosis and characterise the genetic diversity of circulating measles genotypes in Ireland. STUDY DESIGN: 704 cases of acute measles infection as determined by the presence of measles specific IgM in sera and oral fluids were confirmed at the National Virus Reference Laboratory. Measles positive samples (n=116) were examined by genotyping, sequence analysis and phylogenetic characterisation. RESULTS: Three measles outbreaks occurred over the study period: 2004, 2009/2010 and 2011. Measles IgM positivity ranged from 22-29% in outbreak years to 5-10% in the intervening years. Age profile analysis revealed that whereas individuals >10 years accounted for only 8% of cases in the 2004 outbreak, this increased to 33% and 29% in the 2009/2010 and 2011 outbreaks, respectively. The <1 year cohort accounted for 18-20% of cases in all outbreaks. Phylogenetic analysis demonstrated both indigenous transmission and also importation events. Clade D viruses were exclusively found circulating in Ireland, with autochthonous transmission of diverse genotype D4 strains associated with large outbreaks across Europe. More recently, genotype D8 was identified and these were associated with importation events. CONCLUSIONS: This study provides a comprehensive genetic analysis of circulating measles genotypes in Ireland and discriminated between indigenous and imported viral strains. Notably, an increase in laboratory-confirmed measles cases in the greater than 10 years of age group was seen over the study period. This information is valuable to inform vaccination strategies with a focus on those populations who remain susceptible to measles infection.


Assuntos
Anticorpos Antivirais/sangue , Vírus do Sarampo/genética , Sarampo/epidemiologia , RNA Viral/genética , Adolescente , Envelhecimento , Sequência de Bases , Criança , Pré-Escolar , Surtos de Doenças , Feminino , Variação Genética , Humanos , Imunoglobulina M/sangue , Lactente , Irlanda/epidemiologia , Masculino , Sarampo/transmissão , Sarampo/virologia , Vírus do Sarampo/classificação , Vacina contra Sarampo-Caxumba-Rubéola/uso terapêutico , Filogenia , Estudos Retrospectivos , Análise de Sequência de RNA , Estudos Soroepidemiológicos , Vacinação , Adulto Jovem
14.
Pediatr Transplant ; 17(8): 806-14, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24118875

RESUMO

Studies have identified solid organ transplant recipients who remain asymptomatic despite maintaining CHL. Factors which determine the CHL state remain poorly understood but are likely to involve immunological control of the viral infection. We monitored expression of PD-1, a marker of T-cell exhaustion and viral persistence, on CD8 T cells in patients who resolved EBV infection as determined by undetectable EBV DNA (REI) and CHL patients. PD-1 expression on CD8 T cells was increased in the first year post-transplant irrespective of EBV outcome, and most CD8 T cells continued to express PD-1 for up to three yr post-transplant. Although all patient groups showed similar frequencies of EBV-specific CD8+ T cells, PD-1 expression on these cells increased in the post-transplant groups compared with the pretransplant patients. Functional studies of EBV-specific CD8+ T cells stimulated with BZLF or LMP2 peptide pools revealed monofunctional IFN-γ responses. Our results indicate that PD-1 expression on CD8 T cells post-transplant may result from factors other than antigenic stimulation.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Infecções por Vírus Epstein-Barr/metabolismo , Transplante de Rim , Receptor de Morte Celular Programada 1/metabolismo , Insuficiência Renal/terapia , Adolescente , Antígenos Virais/imunologia , Criança , Pré-Escolar , Doença Crônica , Estudos de Coortes , Infecções por Vírus Epstein-Barr/complicações , Feminino , Perfilação da Expressão Gênica , Humanos , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Interferon gama/imunologia , Masculino , Fenótipo , Período Pós-Operatório , Insuficiência Renal/complicações , Carga Viral
16.
J Clin Virol ; 53(4): 320-4, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22269391

RESUMO

BACKGROUND: Two recent mumps outbreaks have occurred in Ireland in 2004/2005 and 2008/2009. OBJECTIVES: To retrospectively investigate any potential shifts in the gender bias and age profile and to identify cohorts who are maintaining mumps virus in circulation. STUDY DESIGN: 2600 cases of acute mumps infection, as determined by the presence of mumps-specific IgM in sera and oral fluids, were confirmed at the National Virus Reference Laboratory. RESULTS: Acute mumps infection occurred more frequently in males with a ratio of approximately 2:1 in the 1-9 and 10-19 years old age groups. A 3:2 ratio was observed in the 20-29 years old cohort and the 30+ age group did not show a gender bias. Serological evidence of prior immunological exposure to mumps virus, as determined by the presence of mumps-specific IgG, was high and similar in males and females of all age cohorts (93.1-100%). A significant increase in the number of acute mumps cases in the ≥30 years old age group was observed. This increase was most striking in the periods between the outbreaks (71.1% in 2007 and 56.2% in 2010). CONCLUSIONS: Acute mumps infection showed a male gender bias. The consistent and significant increase of mumps infection in the ≥30 years old age group which is also evident in the periods between outbreaks suggests that this may be the cohort maintaining the mumps virus in circulation.


Assuntos
Anticorpos Antivirais/sangue , Surtos de Doenças , Vírus da Caxumba/imunologia , Caxumba/epidemiologia , Doença Aguda , Adolescente , Adulto , Distribuição por Idade , Especificidade de Anticorpos , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Irlanda/epidemiologia , Masculino , Caxumba/diagnóstico , Caxumba/imunologia , Caxumba/virologia , Vírus da Caxumba/genética , Vírus da Caxumba/isolamento & purificação , Estudos Soroepidemiológicos , Distribuição por Sexo , Adulto Jovem
17.
Biores Open Access ; 1(6): 291-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23514966

RESUMO

The Epstein-Barr virus early antigen (EBV EA) complex consists of multiple proteins with potential significance for diagnosis of EBV-related diseases. In many individuals, detection of antibody to the early antigen (EA) is a sign of active infection, but 20% of healthy people may have this antibody for years. We studied the role of EA immunoglobulin G (IgG) in individuals with atypical antibody responses in the diagnosis of infectious mononucleosis (IM) and in EBV-infected transplant patients. EA IgG was present in 72% of confirmed IM patients. A trend was observed between high viral loads and the presence of EA IgG and between low viral loads and the absence of EA IgG in EBV-associated disease negative liver transplant recipients. Three assays that measure serum EA IgG were compared; enzyme-linked immunosorbent assay (ELISA), chemiluminescent immunoassay (CLIA), and immunoblot assay. The automated CLIA was found to be more accurate than the ELISA when using the immunoblot assay as a "gold standard" assay in the detection of EA IgG. There may be a potential role for EA IgG testing, together with EBV viral load, in the prediction of transplant recipients at risk of EBV-associated disease; however, EA IgG does not play a significant role in the differential diagnosis of EBV infection in immunocompetent individuals.

18.
Liver Transpl ; 17(12): 1420-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21837744

RESUMO

Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disorder (PTLD) is a life-threatening complication after adult orthotopic liver transplantation (AOLT). Besides EBV and immunosuppression, relatively little is known about the pretransplant clinical parameters associated with the risk of PTLD, and the benefit of using EBV surveillance to predict EBV-associated disease in AOLT patients is uncertain. The aims of this single-center study were to monitor EBV viral loads (VLs) in AOLT patients and to investigate any associations with age, sex, cytomegalovirus (CMV) serostatus, posttransplant times, and indications for transplantation. 1275 blood samples that were collected from 197 AOLT patients 1 day to more than 15 years after transplantation were investigated with quantitative polymerase chain reaction for EBV and CMV DNA. Seventy-two percent of the patients had EBV DNAemia less than 100 days after transplantation without clinical manifestations. No association was observed between the EBV copy numbers and the time since transplantation. EBV DNAemia was weakly associated with male sex but was not associated with age, CMV serostatus, or indications for AOLT. The highest EBV VL levels were observed in patients who presented with congenital liver diseases, whereas patients with viral hepatitis maintained high EBV VLs after transplantation. None of the patients developed PTLD during the study period; however, 3 patients presented with EBV-associated diseases. In conclusion, EBV DNAemia is common in AOLT patients, and routine EBV surveillance has limited value for predicting EBV-associated morbidity or mortality.


Assuntos
DNA Viral/sangue , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/genética , Transplante de Fígado/efeitos adversos , Transtornos Linfoproliferativos/diagnóstico , Adolescente , Adulto , Fatores Etários , Idoso , Citomegalovirus/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Humanos , Imunossupressores/efeitos adversos , Irlanda , Modelos Lineares , Transtornos Linfoproliferativos/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Carga Viral , Adulto Jovem
19.
Transplantation ; 92(3): 328-33, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21685826

RESUMO

BACKGROUND: Studies have identified solid organ transplant recipients who remain asymptomatic despite maintaining chronic high Epstein-Barr virus (EBV) viral loads. We examined clinical manifestations, EBV gene expression, human leukocyte antigen (HLA) alleles, and specific T-cell responses to EBV infection in pediatric renal transplant patients. METHODS: Seventeen pediatric renal transplant patients were categorized according to EBV viral load into those with chronic high viral loads (CHL) and recipients who resolve EBV infection (REI). EBV gene expression was analyzed using real-time PCR assays and EBV-specific T cells were analyzed by flow cytometry. RESULTS: EBV gene, EBV-encoded small RNA 1, was expressed at significantly higher levels in CHL compared with EBV seropositive controls (P=0.005) and raised compared with REI. BamHI A right-ward transcripts were also expressed at higher levels in CHL patients (P=0.03) than in REI. Expression of latent genes, EBNA1, LMP1, LMP2, and lytic gene BZLF1 were restricted to the CHL group with viral gene expression varying over time. HLA-A*02 allele expression was predominant in CHL patients (80%) and GLC lytic-specific cytotoxic T-lymphocytes were absent. In contrast, HLA-B*08 allele expression was prevalent in REI patients (71%) and RAK lytic cytotoxic T-lymphocytes were detected in all patients. CONCLUSION: EBV gene expression in CHL carriers differs from those that resolve infection and should be interpreted alongside HLA polymorphisms.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/imunologia , Antígenos HLA/genética , Herpesvirus Humano 4/genética , Transplante de Rim , Carga Viral/genética , Adolescente , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Criança , Pré-Escolar , Doença Crônica , Feminino , Perfilação da Expressão Gênica , Regulação Viral da Expressão Gênica , Antígenos HLA/imunologia , Humanos , Lactente , Masculino , Complicações Pós-Operatórias/genética , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/virologia , RNA Viral/genética , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral/imunologia
20.
J Clin Microbiol ; 48(11): 3956-62, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20810771

RESUMO

Human cytomegalovirus (HCMV) strains may be genotyped based on polymorphisms that exist within the UL144 gene, which is one of 19 viral genes lost in attenuated laboratory strains. In the present study, UL144 genotypes in congenitally infected babies (congenital cytomegalovirus [cCMV]) were determined, and the relationship between the genotype, viral load, cytokine profile, and patient developmental outcome was investigated. All cCMV infections identified during 2006 and 2007 were included (n = 29). A portion of the infants were clinically assessed at birth and at 12 to 18 months postinfection for cCMV clinical sequelae (n = 18/29). The plasma viral load (PVL) was requested for 23/29 patients, and the UL144 genotype was determined (n = 27/29). The cytokine profile in patient plasma or serum was assessed (n = 20/29). UL144 genotypes A, B, and C were detected within the cCMV population at 33.3%, 29.6%, and 25.9%, respectively. UL144 A and C were associated with a high PVL (P < 0.04). Furthermore, a significant association between the developmental outcome and UL144 A and C was observed (P < 0.04). Only patients infected with UL144 B and A/B were described as having a normal clinical outcome. In addition, a significant correlation between interleukin 10 (IL-10) levels and the PVL was observed (P < 0.04); however, there was no association between the genotype and the cytokine profile. The present study determined that the specific detection of UL144 genotypes A and C was indicative of serious cCMV infection and more likely to lead to long-term cCMV-associated clinical manifestations. The inclusion of HCMV UL144 genotyping along with the recommended PVL monitoring following cCMV diagnosis may aid prediction of the clinical outcome.


Assuntos
Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/patologia , Citomegalovirus/genética , Citomegalovirus/patogenicidade , Glicoproteínas de Membrana/genética , Polimorfismo Genético , Proteínas Virais/genética , Viremia/virologia , Desenvolvimento Infantil , Citocinas/sangue , Infecções por Citomegalovirus/virologia , DNA Viral/química , DNA Viral/genética , Genótipo , Desenvolvimento Humano , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Plasma/imunologia , Plasma/virologia , Análise de Sequência de DNA , Soro/imunologia , Soro/virologia , Carga Viral , Virulência , Fatores de Virulência/genética
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