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1.
Front Immunol ; 14: 1287388, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022529

RESUMO

Obesity is a known risk factor for severe respiratory tract infections. In this prospective study, we assessed the impact of being obese or overweight on longitudinal SARS-CoV-2 humoral and cellular responses up to 18 months after infection. 274 patients provided blood samples at regular time intervals up to 18 months including obese (BMI ≥30, n=32), overweight (BMI 25-29.9, n=103) and normal body weight (BMI 18.5-24.9, n=134) SARS-CoV-2 patients. We determined SARS-CoV-2 spike-specific IgG, IgA, IgM levels by ELISA and neutralising antibody titres by neutralisation assay. RBD- and spike-specific memory B cells were investigated by ELISpot, spike- and non-spike-specific IFN-γ, IL-2 and IFN-γ/IL-2 secreting T cells by FluoroSpot and T cell receptor (TCR) sequencing was performed. Higher BMI correlated with increased COVID-19 severity. Humoral and cellular responses were stronger in overweight and obese patients than normal weight patients and associated with higher spike-specific IgG binding titres relative to neutralising antibody titres. Linear regression models demonstrated that BMI, age and COVID-19 severity correlated independently with higher SARS-CoV-2 immune responses. We found an increased proportion of unique SARS-CoV-2 specific T cell clonotypes after infection in overweight and obese patients. COVID-19 vaccination boosted humoral and cellular responses irrespective of BMI, although stronger immune boosting was observed in normal weight patients. Overall, our results highlight more severe disease and an over-reactivity of the immune system in overweight and obese patients after SARS-CoV-2 infection, underscoring the importance of recognizing overweight/obese individuals as a risk group for prioritisation for COVID-19 vaccination.


Assuntos
COVID-19 , Sobrepeso , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Interleucina-2 , Estudos Prospectivos , Obesidade/complicações , Imunoglobulina G , Anticorpos Antivirais , ELISPOT , Imunidade , Anticorpos Neutralizantes
3.
Int J Nurs Stud ; 143: 104496, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37156080

RESUMO

BACKGROUND: The complex nature of leadership in nursing and healthcare requires a vast skill set. Leadership self-efficacy (LSE) has emerged as an important concept to support leadership development in the nursing literature. An analysis of LSE can clarify and inform strategies for leadership development among nurses. OBJECTIVE: To clarify the concept of LSE and understand how it relates to nurses' motivation and aspiration for formal leadership roles. METHOD: A concept analysis using Rodgers' evolutionary method identified attributes, antecedents, and consequences of LSE. Twenty-three articles published between 1993 and 2022 were analyzed following a Boolean search of four databases - Academic Search Complete, CINAHL, MEDLINE, and Scopus. RESULTS: LSE is an important element of nurses' aspiration to leadership. Leadership training, individual traits, and organizational support affect levels of LSE. When LSE is increased, job performance and nurses' motivation to take on formal leadership increase. CONCLUSION: The concept analysis further expands knowledge about factors that affect LSE. It provides data on how LSE can be harnessed to support leadership development and career aspiration for nurses. Developing and nurturing LSE among nurses may be key in promoting leadership career aspirations. Nurse leaders in practice, research, and academia can use this knowledge as a guide in leadership program development.


Assuntos
Liderança , Enfermeiras e Enfermeiros , Humanos , Autoeficácia , Motivação , Instalações de Saúde
4.
Front Immunol ; 14: 1155552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143658

RESUMO

Introduction: The haemagglutination inhibition assay (HAI) and the virus microneutralisation assay (MN) are long-established methods for quantifying antibodies against influenza viruses. Despite their widespread use, both assays require standardisation to improve inter-laboratory agreement in testing. The FLUCOP consortium aims to develop a toolbox of standardised serology assays for seasonal influenza. Building upon previous collaborative studies to harmonise the HAI, in this study the FLUCOP consortium carried out a head-to-head comparison of harmonised HAI and MN protocols to better understand the relationship between HAI and MN titres, and the impact of assay harmonisation and standardisation on inter-laboratory variability and agreement between these methods. Methods: In this paper, we present two large international collaborative studies testing harmonised HAI and MN protocols across 10 participating laboratories. In the first, we expanded on previously published work, carrying out HAI testing using egg and cell isolated and propagated wild-type (WT) viruses in addition to high-growth reassortants typically used influenza vaccines strains using HAI. In the second we tested two MN protocols: an overnight ELISA-based format and a 3-5 day format, using reassortant viruses and a WT H3N2 cell isolated virus. As serum panels tested in both studies included many overlapping samples, we were able to look at the correlation of HAI and MN titres across different methods and for different influenza subtypes. Results: We showed that the overnight ELISA and 3-5 day MN formats are not comparable, with titre ratios varying across the dynamic range of the assay. However, the ELISA MN and HAI are comparable, and a conversion factor could possibly be calculated. In both studies, the impact of normalising using a study standard was investigated, and we showed that for almost every strain and assay format tested, normalisation significantly reduced inter-laboratory variation, supporting the continued development of antibody standards for seasonal influenza viruses. Normalisation had no impact on the correlation between overnight ELISA and 3-5 day MN formats.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Humanos , Vírus da Influenza A Subtipo H3N2 , Hemaglutinação , Estações do Ano , Anticorpos Antivirais
5.
Front Immunol ; 14: 1129765, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36926342

RESUMO

Introduction: External Quality Assessment (EQA) schemes are designed to provide a snapshot of laboratory proficiency, identifying issues and providing feedback to improve laboratory performance and inter-laboratory agreement in testing. Currently there are no international EQA schemes for seasonal influenza serology testing. Here we present a feasibility study for conducting an EQA scheme for influenza serology methods. Methods: We invited participant laboratories from industry, contract research organizations (CROs), academia and public health institutions who regularly conduct hemagglutination inhibition (HAI) and microneutralization (MN) assays and have an interest in serology standardization. In total 16 laboratories returned data including 19 data sets for HAI assays and 9 data sets for MN assays. Results: Within run analysis demonstrated good laboratory performance for HAI, with intrinsically higher levels of intra-assay variation for MN assays. Between run analysis showed laboratory and strain specific issues, particularly with B strains for HAI, whilst MN testing was consistently good across labs and strains. Inter-laboratory variability was higher for MN assays than HAI, however both assays showed a significant reduction in inter-laboratory variation when a human sera pool is used as a standard for normalization. Discussion: This study has received positive feedback from participants, highlighting the benefit such an EQA scheme would have on improving laboratory performance, reducing inter laboratory variation and raising awareness of both harmonized protocol use and the benefit of biological standards for seasonal influenza serology testing.


Assuntos
Influenza Humana , Humanos , Hemaglutinação , Laboratórios , Estudos de Viabilidade , Estações do Ano
6.
NPJ Vaccines ; 7(1): 67, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750781

RESUMO

History of influenza A/H3N2 exposure, especially childhood infection, shape antibody responses after influenza vaccination and infection, but have not been extensively studied. We investigated the breadth and durability of influenza A/H3N2-specific hemagglutinin-inhibition antibodies after live-attenuated influenza vaccine in children (aged 3-17 years, n = 42), and after inactivated influenza vaccine or infection in adults (aged 22-61 years, n = 42) using 14 antigenically distinct A/H3N2 viruses circulating from 1968 to 2018. We found that vaccination and infection elicited cross-reactive antibody responses, predominantly directed against newer or future strains. Childhood H3-priming increased the breadth and magnitude of back-boosted A/H3N2-specific antibodies in adults. Broader and more durable A/H3N2-specific antibodies were observed in repeatedly vaccinated adults than in children and previously unvaccinated adults. Our findings suggest that early A/H3N2 exposure and frequent seasonal vaccination could increase the breadth and seropositivity of antibody responses, which may improve vaccine protection against future viruses.

7.
Commun Med (Lond) ; 2: 36, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603265

RESUMO

Background: Evaluation of susceptibility to emerging SARS-CoV-2 variants of concern (VOC) requires rapid screening tests for neutralising antibodies which provide protection. Methods: Firstly, we developed a receptor-binding domain-specific haemagglutination test (HAT) to Wuhan and VOC (alpha, beta, gamma and delta) and compared to pseudotype, microneutralisation and virus neutralisation assays in 835 convalescent sera. Secondly, we investigated the antibody response using the HAT after two doses of mRNA (BNT162b2) vaccination. Sera were collected at baseline, three weeks after the first and second vaccinations from older (80-99 years, n = 89) and younger adults (23-77 years, n = 310) and compared to convalescent sera from naturally infected individuals (1-89 years, n = 307). Results: Here we show that HAT antibodies highly correlated with neutralising antibodies (R = 0.72-0.88) in convalescent sera. Home-dwelling older individuals have significantly lower antibodies to the Wuhan strain after one and two doses of BNT162b2 vaccine than younger adult vaccinees and naturally infected individuals. Moverover, a second vaccine dose boosts and broadens the antibody repertoire to VOC in naïve, not previously infected older and younger adults. Most (72-76%) older adults respond after two vaccinations to alpha and delta, but only 58-62% to beta and gamma, compared to 96-97% of younger vaccinees and 68-76% of infected individuals. Previously infected older individuals have, similarly to younger adults, high antibody titres after one vaccination. Conclusions: Overall, HAT provides a surrogate marker for neutralising antibodies, which can be used as a simple inexpensive, rapid test. HAT can be rapidly adaptable to emerging VOC for large-scale evaluation of potentially decreasing vaccine effectiveness.

8.
Nat Med ; 27(9): 1607-1613, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34163090

RESUMO

Long-term complications after coronavirus disease 2019 (COVID-19) are common in hospitalized patients, but the spectrum of symptoms in milder cases needs further investigation. We conducted a long-term follow-up in a prospective cohort study of 312 patients-247 home-isolated and 65 hospitalized-comprising 82% of total cases in Bergen during the first pandemic wave in Norway. At 6 months, 61% (189/312) of all patients had persistent symptoms, which were independently associated with severity of initial illness, increased convalescent antibody titers and pre-existing chronic lung disease. We found that 52% (32/61) of home-isolated young adults, aged 16-30 years, had symptoms at 6 months, including loss of taste and/or smell (28%, 17/61), fatigue (21%, 13/61), dyspnea (13%, 8/61), impaired concentration (13%, 8/61) and memory problems (11%, 7/61). Our findings that young, home-isolated adults with mild COVID-19 are at risk of long-lasting dyspnea and cognitive symptoms highlight the importance of infection control measures, such as vaccination.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/complicações , COVID-19/patologia , Disfunção Cognitiva/virologia , Dispneia/virologia , Fadiga/virologia , Adolescente , Adulto , Ageusia/virologia , Anosmia/virologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Noruega , Isolamento de Pacientes , Estudos Prospectivos , SARS-CoV-2 , Índice de Gravidade de Doença , Adulto Jovem , Síndrome de COVID-19 Pós-Aguda
9.
Lancet Reg Health Eur ; 3: 100014, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33871470

RESUMO

BACKGROUND: Households studies reflect the natural spread of SARS-CoV-2 in immunologically naive populations with limited preventive measures to control transmission.We hypothesise that seropositivity provides more accurate household attack rates than RT-PCR. Here, we investigated the importance of age in household transmission dynamics. METHODS: We enroled 112 households (291 participants) in a case-ascertained study in Bergen, Norway from 28th February to 4th April 2020, collecting demographic and clinical data from index patients and household members. SARS-CoV-2-specific antibodies were measured in sera collected 6-8 weeks after index patient nasopharyngeal testing to define household attack rates. FINDINGS: The overall attack rate was 45% (95% CI 38-53) assessed by serology, and 47% when also including seronegative RT-PCR positives. Serology identified a higher number of infected household members than RT-PCR. Attack rates were equally high in children (48%) and young adults (42%). The attack rate was 16% in asymptomatic household members and 42% in RT-PCR negative contacts. Older adults had higher antibody titres than younger adults. The risk of household transmission was higher when the index patient had fever (aOR 3.31 [95% CI 1.52-7.24]; p = 0.003) or dyspnoea (aOR 2.25 [95% CI 1.80-4.62]; p = 0.027) during acute illness. INTERPRETATION: Serological assays provide more sensitive and robust estimates of household attack rates than RT-PCR. Children are equally susceptible to infection as young adults. Negative RT-PCR or lack of symptoms are not sufficient to rule out infection in household members. FUNDING: Helse Vest (F-11628), Trond Mohn Foundation (TMS2020TMT05).

10.
J Infect Dis ; 221(1): 21-32, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31250024

RESUMO

BACKGROUND: Influenza remains a major threat to public health. Live-attenuated influenza vaccines (LAIV) have been shown to be effective, particularly in children. Follicular T helper (TFH) cells provide B-cell help and are crucial for generating long-term humoral immunity. However the role of TFH cells in LAIV-induced immune responses is unknown. METHODS: We collected tonsils, plasma, and saliva samples from children and adults receiving LAIV prior to tonsillectomy. We measured influenza-specific TFH-cell responses after LAIV by flow cytometry and immunohistochemistry. Systemic and local antibody responses were analysed by hemagglutination inhibition assay and enzyme-linked immunosorbent assay. RESULTS: We report that LAIV induced early (3-7 days post-vaccination) activation of tonsillar follicles and influenza-specific TFH-cell (CXCR5+CD57+CD4+ T cell) responses in children, and to a lesser extent in adults. Serological analyses showed that LAIV elicited rapid (day 14) and long-term (up to 1 year post-vaccination) antibody responses (hemagglutination inhibition, influenza-specific IgG) in children, but not adults. There was an inverse correlation between pre-existing influenza-specific salivary IgA concentrations and tonsillar TFH-cell responses, and a positive correlation between tonsillar TFH-cell and systemic IgG induction after LAIV. CONCLUSIONS: Our data, taken together, demonstrate an important role of tonsillar TFH cells in LAIV-induced immunity in humans.


Assuntos
Anticorpos Antivirais/sangue , Imunogenicidade da Vacina , Vacinas contra Influenza/imunologia , Tonsila Palatina/imunologia , Saliva/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Vírus da Influenza B/imunologia , Pessoa de Meia-Idade , Tonsila Palatina/citologia , Fatores de Tempo , Vacinação , Vacinas Atenuadas , Adulto Jovem
11.
Scand J Immunol ; 90(4): e12801, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31269273

RESUMO

Influenza virus is a major respiratory pathogen, and vaccination is the main method of prophylaxis. In 2012, the trivalent live attenuated influenza vaccine (LAIV) was licensed in Europe for use in children. Vaccine-induced antibodies directed against the main viral surface glycoproteins, haemagglutinin (HA) and neuraminidase (NA) play important roles in limiting virus infection. The objective of this study was to dissect the influenza-specific antibody responses in children and adults, and T cell responses in children induced after LAIV immunization to the A/H1N1 virus. Blood samples were collected pre- and at 28 and 56 days post-vaccination from 20 children and 20 adults. No increase in micro-neutralization (MN) antibodies against A/H1N1 was observed after vaccination. A/H1N1 stalk-specific neutralizing and NA-inhibiting (NI) antibodies were boosted in children after LAIV. Interferon γ-producing T cells increased significantly in children, and antibody-dependent cellular-mediated cytotoxic (ADCC) cell activity increased slightly in children after vaccination, although this change was not significant. The results indicate that the NI assay is more sensitive to qualitative changes in serum antibodies after LAIV. There was a considerable difference in the immune response in children and adults after vaccination, which may be related to priming and previous influenza history. Our findings warrant further studies for evaluating LAIV vaccination immunogenicity.


Assuntos
Vírus da Influenza A Subtipo H1N1/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Vacinas Atenuadas/imunologia , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Criança , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Imunidade Humoral , Masculino , Vacinação
12.
Nurs Leadersh (Tor Ont) ; 32(1): 42-59, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31228344

RESUMO

This research examined the role and scope of licensed practical nurses (LPNs) in home care (HC) and case management. Case management is relatively new to LPNs in Alberta having been added to their list of competencies in 2015. The extent to which LPNs are performing functions and the circumstances or criteria that shape their reported case management functions and role are not clear. Our research questions were: a) What roles do LPNs play within HC and case management? and b) What roles could LPNs play within HC and case management given their scope of practice to achieve optimal client outcomes and system efficiencies? We used a mixed methods multiple case study design to engage LPNs in case management practice, their managers and HC leaders from rural, urban and suburban HC offices. Approaches for data collection included semi-structured interviews, participant observation, focus groups, document review and survey.


Assuntos
Serviços de Assistência Domiciliar/normas , Técnicos de Enfermagem/normas , Alberta , Administração de Caso/tendências , Serviços de Assistência Domiciliar/tendências , Humanos , Papel do Profissional de Enfermagem , Inquéritos e Questionários
14.
NPJ Vaccines ; 3: 37, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30131880

RESUMO

Annual seasonal influenza vaccination is recommended for high-risk populations and often occupational groups such as healthcare workers (HCWs). Repeated annual vaccination has been reported to either have no impact or reduce antibody responses or protection. However, whether repeated vaccination influences T-cell responses has not been sufficiently studied, despite the increasing evidence of the protective roles of T-cell immunity. Here, we explored the impact of repeated annual vaccination with the same vaccine strain (H1N1pdm09) over multiple seasons in the post-2009 pandemic era and showed that repeated vaccination increased both T-cell and humoral responses. Using the T-cell FluroSpot and intracellular cytokine-staining, the hemagglutination inhibition (HI), and the memory B-cell (MBC) ELISpot assays, we investigated pre- and postvaccination T cells, antibodies, and MBCs in a cohort of HCWs repeatedly vaccinated with H1N1pdm09 for 5 years (pandemic vaccination in 2009 and subsequently annual seasonal vaccination containing H1N1pdm09 during 2010-2013). We found that the prevaccination H1N1pdm09-specific T cells, antibodies, and MBCs were significantly increased after 3-4 repeated vaccinations and maintained at high levels throughout seasons 2012 and 2013. The cross-reactive IFN-γ-secreting CD4+ cells recognizing conserved viral external or internal epitopes were also maintained throughout 2012 and 2013. Repeated vaccination improved the multifunctional memory CD4+ responses. Particularly, the IFN-γ+TNF-α+CD4+ T cells were boosted following each vaccination. HI antibodies were significantly induced after each vaccination over 5 years. Our findings indicate a broad impact of repeated annual vaccination, even with the same vaccine component, on the influenza-specific T-cell and humoral immunity and support the continuing recommendation of annual influenza vaccination. Despite the widespread implementation of annual influenza vaccination, the effect of repeated vaccinations on the immune response in subsequent seasons is poorly understood. A team led by Rebecca Jane Cox at the University of Bergen examined the humoral and T-cell response elicited by 2009's H1N1pdm09 seasonal vaccine. Since the H1N1pdm09 strain continued to circulate in subsequent years it was included in later vaccine formulations and the authors could therefore examine the effects of repeated annual vaccination over multiple seasons. They observed that H1N1pdm09-specific polyfunctional T-cell responses and antibodies were enhanced by multiple annual vaccinations. In particular, T cells showed progressive skewing to IFN-γ+TNF+ double producers, but the magnitude of the T-cell response tended to plateau after 3-4 repeated vaccinations. The findings suggest that including the same component in subsequent annual vaccines can significantly impact the influenza immune response.

15.
J Infect Dis ; 215(5): 740-749, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28007925

RESUMO

Background: Annual vaccination for healthcare workers and other high-risk groups is the mainstay of the public health strategy to combat influenza. Inactivated influenza vaccines confer protection by inducing neutralizing antibodies efficiently against homologous and closely matched virus strains. In the absence of neutralizing antibodies, cross-reactive T cells have been shown to limit disease severity. However, animal studies and a study in immunocompromised children suggested that repeated vaccination hampers CD8+ T cells. Yet the impact of repeated annual influenza vaccination on both cross-reactive CD4+ and CD8+ T cells has not been explored, particularly in healthy adults. Methods: We assembled a unique cohort of healthcare workers who received a single AS03-adjuvanted H1N1pdm09 vaccine in 2009 and subsequently either repeated annual vaccination or no further vaccination during 2010-2013. Blood samples were collected before the influenza season or vaccination to assess antibody and T-cell responses. Results: Antibody titers to H1N1pdm09 persisted above the protective level in both the repeated- and single-vaccination groups. The interferon γ+ (IFN-γ+) and multifunctional CD4+ T-cell responses were maintained in the repeated group but declined significantly in the single-vaccination group. The IFN-γ+CD8+ T cells remained stable in both groups. Conclusions: This study provides the immunological evidence base for continuing annual influenza vaccination in adults.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Estudos de Coortes , Reações Cruzadas , Feminino , Seguimentos , Humanos , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Masculino , Pessoa de Meia-Idade , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/uso terapêutico
16.
J Infect Dis ; 214(5): 722-31, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27247344

RESUMO

BACKGROUND: Tonsils play a key role in eliciting immune responses against respiratory pathogens. Little is known about how tonsils contribute to the local immune response after intranasal vaccination. Here, we uniquely report the mucosal humoral responses in tonsils and saliva after intranasal live attenuated influenza vaccine (LAIV) vaccination in children. METHODS: Blood, saliva, and tonsils samples were collected from 39 children before and after LAIV vaccination and from 16 age-matched, nonvaccinated controls. Serum antibody responses were determined by a hemagglutination inhibition (HI) assay. The salivary immunoglobulin A (IgA) level was measured by an enzyme-linked immunosorbent assay. Antibody-secreting cell (ASC) and memory B-cell (MBC) responses were enumerated in tonsils and blood. RESULTS: Significant increases were observed in levels of serum antibodies and salivary IgA to influenza A(H3N2) and influenza B virus strains as early as 14 days after vaccination but not to influenza A(H1N1). Influenza virus-specific salivary IgA levels correlated with serum HI responses, making this a new possible indicator of vaccine immunogenicity in children. LAIV augmented influenza virus-specific B-cell responses in tonsils and blood. Tonsillar MBC responses correlated with systemic MBC and serological responses. Naive children showed significant increases in MBC counts after LAIV vaccination. CONCLUSIONS: This is the first study to demonstrate that LAIV elicits humoral B-cell responses in tonsils of young children. Furthermore, salivary IgA analysis represents an easy method for measuring immunogenicity after vaccination.


Assuntos
Anticorpos Antivirais/análise , Linfócitos B/imunologia , Vacinas contra Influenza/imunologia , Tonsila Palatina/imunologia , Administração Intranasal , Adolescente , Células Apresentadoras de Antígenos/imunologia , Sangue/imunologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Imunoglobulina A/análise , Vacinas contra Influenza/administração & dosagem , Masculino , Saliva/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
17.
Vaccine ; 34(31): 3576-83, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27219339

RESUMO

BACKGROUND: We analyzed the impact of the anti-T-cell agents basiliximab and antithymocyte globulins (ATG) on antibody and cell-mediated immune responses after influenza vaccination in solid-organ transplant recipients. METHODS: 71 kidney and heart transplant recipients (basiliximab [n=43] and ATG [n=28]) received the trivalent influenza vaccine. Antibody responses were measured at baseline and 6 weeks post-vaccination by hemagglutination inhibition assay; T-cell responses were measured by IFN-γ ELISpot assays and intracellular cytokine staining (ICS); and influenza-specific memory B-cell (MBC) responses were evaluated using ELISpot. RESULTS: Median time of vaccination from transplantation was 29 months (IQR 8-73). Post-vaccination seroconversion rates were 26.8% for H1N1, 34.1% for H3N2 and 4.9% for influenza B in the basiliximab group and 35.7% for H1N1, 42.9% for H3N2 and 14.3% for influenza B in the ATG group (p=0.44, p=0.61, and p=0.21, respectively). The number of influenza-specific IFN-γ-producing cells increased significantly after vaccination (from 35 to 67.5 SFC/10(6) PBMC, p=0.0007), but no differences between treatment groups were observed (p=0.88). Median number of IgG-MBC did not increase after vaccination (H1N1, p=0.94; H3N2 p=0.34; B, p=0.79), irrespective of the type of anti-T-cell therapy. CONCLUSIONS: After influenza vaccination, a significant increase in antibody and T-cell immune responses but not in MBC responses was observed in transplant recipients. Immune responses were not significantly different between groups that received basiliximab or ATG.


Assuntos
Imunidade Celular , Imunidade Humoral , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Transplantados , Adulto , Anticorpos Monoclonais/uso terapêutico , Soro Antilinfocitário/uso terapêutico , Linfócitos B/imunologia , Basiliximab , Feminino , Transplante de Coração , Testes de Inibição da Hemaglutinação , Humanos , Memória Imunológica , Imunossupressores/uso terapêutico , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes de Fusão/uso terapêutico , Linfócitos T/imunologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-29250435

RESUMO

Traditionally, neutralising antibodies that are directed to the major surface glycoprotein hemagglutinin (HA) head domain are measured as surrogate correlates of protection against influenza. In addition to neutralization, hemagglutinin-specific antibodies may provide protection by mediating antibody-dependent cellular cytotoxicity (ADCC). During the 2009 pandemic, vaccination induced HA-specific antibodies that were mostly directed to the conserved HA stalk domain. However, the protective role of these antibodies has not been investigated in detail. We quantified the HA head and stalk-specific antibodies, their avidity, ability to neutralise virus and activate natural killer cells in an ADCC assay. We analyzed sera obtained from 14 healthcare workers who had low hemagglutination inhibition (HI) antibody titres at 3 months after pandemic H1N1 vaccination as well as from 22 controls. Vaccination resulted in a HA stalk dominant antibody response in both low responders and controls. Revaccination of low responders, 5 months later, resulted in a boost in antibodies, with HA head-specific antibodies dominating the response. Comparative analysis of head and stalk antibody avidities revealed that stalk-specific antibodies were qualitatively superior. Furthermore, stalk-specific antibodies mediated virus neutralization and had significantly higher ADCC activity than head-specific antibodies. Despite the head and stalk-specific antibodies being lower in low responders, they had comparable antibody avidity, ADCC functionality and neutralising capacity to those of controls who had high HI titres post-vaccination. Thus, our study has demonstrated that HA stalk-specific antibodies may have an important role in protection through neutralization and ADCC in low responders who do not maintain seroprotective HI antibodies.

19.
Hum Vaccin Immunother ; 11(7): 1654-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26009966

RESUMO

Healthcare workers (HCW) were prioritized for vaccination during the 2009 influenza A(H1N1)pdm09 pandemic. We conducted a clinical trial in October 2009 where 237 HCWs were immunized with a AS03-adjuvanted A(H1N1)pdm09 monovalent vaccine. In the current study, we analyzed the homologous and cross-reactive H1N1 humoral responses using prototype vaccine strains dating back to 1977 by the haemagglutinin inhibition (HI), single radial hemolysis SRH), antibody secreting cell (ASC) and memory B cell (MBC) assays. The cellular responses were assessed by interferon-γ (IFN-γ) ELISPOT and by intracellular staining (ICS) for the Th1 cytokines IFN-γ, interleukin-2 (IL-2) and tumor necrosis factor-α (TNF-α). All assays were performed using blood samples obtained prior to (day 0) and 7, 14 and 21 d post-pandemic vaccination, except for ASC (day 7) and ICS (days 0 and 21). Vaccination elicited rapid HI, SRH and ASC responses against A(H1N1)pdm09 which cross reacted with seasonal H1N1 strains. MBC responses were detected against the homologous and seasonal H1N1 strains before vaccination and were boosted 2 weeks post-vaccination. An increase in cellular responses as determined by IFN-γ ELISPOT and ICS were observed 1-3 weeks after vaccination. Collectively, our data show that the AS03-adjuvanted A(H1N1)pdm09 vaccine induced rapid cellular and humoral responses against the vaccine strain and the response cross-reacted against prototype H1N1 strains dating back to 1977.


Assuntos
Adjuvantes Imunológicos , Pessoal de Saúde , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Esqualeno/imunologia , alfa-Tocoferol/imunologia , Adulto , Anticorpos Antivirais/sangue , Reações Cruzadas , Combinação de Medicamentos , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Imunidade Celular , Imunidade Humoral , Esquemas de Imunização , Influenza Humana/prevenção & controle , Interferon gama/imunologia , Masculino , Pessoa de Meia-Idade , Polissorbatos , Fatores de Tempo
20.
J Nurs Manag ; 22(8): 1027-41, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23758834

RESUMO

AIM: The aim of this review was to report the effectiveness of strategies for retaining experienced Registered Nurses. BACKGROUND: Nursing researchers have noted that the projected nursing shortage, if not rectified, is expected to affect healthcare cost, job satisfaction and quality patient care. Retaining experienced nurses would help to mitigate the shortage, facilitate the transfer of knowledge and provision of quality care to patients. EVALUATION: A systematic review of studies on interventions that promote the retention of experienced Registered Nurses in health care settings. KEY ISSUES: Twelve studies were included in the final analysis. Most studies reported improved retention as a result of the intervention. Team work and individually targeted strategies including mentoring, leadership interest and in-depth orientation increased job satisfaction and produced higher retention results. CONCLUSIONS: Few published studies have examined interventions that promote the retention of experienced Registered Nurses in healthcare. Retention was highest when multiple interventions were used. Further research is needed to inform nurse leaders of ways to retain nurses and to maintain quality care in health care settings. IMPLICATIONS FOR NURSING MANAGEMENT AND LEADERSHIP: Programmes targeting the retention of experienced nurses need to be considered when implementing measures to decrease the nursing shortage and its effects on quality care.


Assuntos
Competência Clínica , Hospitais/normas , Papel do Profissional de Enfermagem/psicologia , Lealdade ao Trabalho , Setor de Assistência à Saúde/normas , Humanos , Liderança , Enfermeiras e Enfermeiros/psicologia
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