74 research outputs found

    CD8+ immunodominance among Epstein-Barr virus lytic cycle antigens directly reflects the efficiency of antigen presentation in lytically infected cells

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    Antigen immunodominance is an unexplained feature of CD8+ T cell responses to herpesviruses, which are agents whose lytic replication involves the sequential expression of immediate early (IE), early (E), and late (L) proteins. Here, we analyze the primary CD8 response to Epstein-Barr virus (EBV) infection for reactivity to 2 IE proteins, 11 representative E proteins, and 10 representative L proteins, across a range of HLA backgrounds. Responses were consistently skewed toward epitopes in IE and a subset of E proteins, with only occasional responses to novel epitopes in L proteins. CD8+ T cell clones to representative IE, E, and L epitopes were assayed against EBV-transformed lymphoblastoid cell lines (LCLs) containing lytically infected cells. This showed direct recognition of lytically infected cells by all three sets of effectors but at markedly different levels, in the order IE > E ≫ L, indicating that the efficiency of epitope presentation falls dramatically with progress of the lytic cycle. Thus, EBV lytic cycle antigens display a hierarchy of immunodominance that directly reflects the efficiency of their presentation in lytically infected cells; the CD8+ T cell response thereby focuses on targets whose recognition leads to maximal biologic effect

    Epitope-specific Evolution of Human CD8+ T Cell Responses from Primary to Persistent Phases of Epstein-Barr Virus Infection

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    Primary virus infection often elicits a large CD8+ T cell response which subsequently contracts to a smaller memory T cell pool; the relationship between these two virus-specific populations is not well understood. Here we follow the human CD8+ T cell response to Epstein-Barr virus (EBV) from its primary phase in infectious mononucleosis (IM) through to the persistent carrier state. Using HLA-A2.1 or B8 tetramers specific for four lytic cycle and three latent cycle epitopes, we find marked differences in the epitope-specific composition of the T cell populations between the two phases of infection. The primary response is dominated by lytic epitope specificities which are severely culled (and in one case extinguished) with resolution of the acute infection; in contrast latent epitope specificities are less abundant, if present at all, in acute IM but often then increase their percentage representation in the CD8 pool. Even comparing epitopes of the same type, the relative size of responses seen in primary infection does not necessarily correlate with that seen in the longer term. We also follow the evolution of phenotypic change in these populations and show that, from a uniform CD45RA−RO+CCR7− phenotype in IM, lytic epitope responses show greater reversion to a CD45RA+RO− phenotype whereas latent epitope responses remain CD45RA−RO+ with a greater tendency to acquire CCR7. Interestingly these phenotypic distinctions reflect the source of the epitope as lytic or latent, and not the extent to which the response has been amplified in vivo

    Up-beat UK: a programme of research into the relationship between coronary heart disease and depression in primary care patients.

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    Coronary heart disease and depression are both common health problems and by 2020 will be the two leading causes of disability worldwide. Depression has been found to be more common in patients with coronary heart disease but the nature of this relationship is uncertain. In the United Kingdom general practitioners are now being remunerated for case-finding for depression in patients with coronary heart disease, however it is unclear how general practitioners should manage these patients. We aim to explore the relationship between coronary heart disease and depression in a primary care population and to develop an intervention for patients with coronary heart disease and depression

    Heightened Epstein-Barr virus immunity and potential cross-reactivities in multiple sclerosis

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    Background: Epstein-Barr virus (EBV) is a likely prerequisite for multiple sclerosis (MS) but the underlying mechanisms are unknown. We investigated antibody and T cell responses to EBV in persons with MS (pwMS), healthy EBV-seropositive controls (HC) and post-infectious mononucleosis (POST-IM) individuals up to 6 months after disease resolution. The ability of EBV-specific T cell responses to target antigens from the central nervous system (CNS) was also investigated.Methods: Untreated persons with relapsing-remitting MS, POST-IM individuals and HC were, as far as possible, matched for gender, age and HLA-DRB1*15:01. EBV load was determined by qPCR, and IgG responses to key EBV antigens were determined by ELISA, immunofluorescence and Western blot, and tetanus toxoid antibody responses by multiplex bead array. EBV-specific T cell responses were determined ex vivo by intracellular cytokine staining (ICS) and cross-reactivity of in vitro-expanded responses probed against 9 novel Modified Vaccinia Ankara (MVA) viruses expressing candidate CNS autoantigens. Results: EBV load in peripheral blood mononuclear cells (PBMC) was unchanged in pwMS compared to HC. Serologically, while tetanus toxoid responses were unchanged between groups, IgG responses to EBNA1 and virus capsid antigen (VCA) were significantly elevated (EBNA1 p = 0.0079, VCA p = 0.0298) but, importantly, IgG responses to EBNA2 and the EBNA3 family antigens were also more frequently detected in pwMS (EBNA2 p = 0.042 and EBNA3 p = 0.005). In ex vivo assays, T cell responses to autologous EBV-transformed B cells and to EBNA1 were largely unchanged numerically, but significantly increased IL-2 production was observed in response to certain stimuli in pwMS. EBV-specific polyclonal T cell lines from both MS and HC showed high levels of autoantigen recognition by ICS, and several neuronal proteins emerged as common targets including MOG, MBP, PLP and MOBP. Discussion: Elevated serum EBV-specific antibody responses in the MS group were found to extend beyond EBNA1, suggesting a larger dysregulation of EBV-specific antibody responses than previously recognised. Differences in T cell responses to EBV were more difficult to discern, however stimulating EBV-expanded polyclonal T cell lines with 9 candidate CNS autoantigens revealed a high level of autoreactivity and indicate a far-reaching ability of the virus-induced T cell compartment to damage the CNS

    Primary EBV infection induces an acute wave of activated antigen-specific cytotoxic CD4+ T cells

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    CD4+ T cells are essential for immune protection against viruses, yet their multiple roles remain ill-defined at the single-cell level in humans. Using HLA class II tetramers, we studied the functional properties and clonotypic architecture of EBV-specific CD4+ T cells in patients with infectious mononucleosis, a symptomatic manifestation of primary EBV infection, and in long-term healthy carriers of EBV.We found that primary infection elicited oligoclonal expansions of TH1-like EBV-specific CD4+ T cells armed with cytotoxic proteins that responded immediately ex vivo to challenge with EBV-infected B cells. Importantly, these acutely generated cytotoxic CD4+ T cells were highly activated and transcriptionally distinct from classically described cytotoxic CD4+ memory T cells that accumulate during other persistent viral infections, including CMVand HIV. In contrast, EBV-specific memory CD4+ T cells displayed increased cytokine polyfunctionality but lacked cytotoxic activity. These findings suggested an important effector role for acutely generated cytotoxic CD4+ T cells that could potentially be harnessed to improve the efficacy of vaccines against EBV

    UPBEAT-UK::a programme of research into the relationship between coronary heart disease and depression in primary care patients

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    Many people with coronary heart disease (CHD) are depressed and research on people who have had a heart attack found that depression increases the chance of further heart attacks. The UPBEAT-UK team conducted research with people on general practitioner CHD registers in 33 south London practices to: examine any link between CHD, depression and worse future heart disease; and develop case\ud management by practice nurses for people with CHD and depression. We followed 803 people with CHD for up to 3 years, assessing them for depression, chest pain and\ud worsening of heart disease, and also measured care costs. We asked patients, GPs and nurses how people with CHD and depression should be treated. From this, we developed care designed for each person called ‘personalised care’ (PC). We tested it in 41 people (while 40 people received their usual care from GPs)\ud with chest pain and depression, to assess how acceptable it is, whether or not it helps and what the costs would be. PC was acceptable to people, and those who received it reported less chest pain 6 and 12 months later. Costs were lower following PC but the difference was not statistically significant. Just under half of those with CHD had chest pain. Depression was frequent, but anxiety was more\ud common and increased the chances of both heart attacks and death. We conclude that further research is needed to understand the links between anxiety, chest pain and heart\ud disease, and to further develop our promising findings that PC can be helpful in reducing chest pain in\ud general practice

    The Impact of Occupational Therapy on the Self‐Management of Rheumatoid Arthritis: A Mixed Methods Systematic Review

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    Objective: To determine the impact of occupational therapy (OT) on the self‐management of function, pain, fatigue, and lived experience for people living with rheumatoid arthritis (RA). Methods: Five databases and gray literature were searched up to June 30, 2022. Three reviewers screened titles and abstracts, with two independently extracting and assessing full texts using the Cochrane risk of bias (quantitative) and Critical Appraisal Skills Programme (qualitative) tools to assess study quality. Studies were categorized into four intervention types. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) (quantitative) and GRADE‐ Confidence in Evidence from Reviews of Qualitative research (qualitative) were used to assess the quality of evidence for each intervention type. Results: Of 39 eligible papers, 29 were quantitative (n = 2,029), 4 qualitative (n = 50), and 6 mixed methods (n = 896). Good evidence supports patient education and behavior change programs for improving pain and function, particularly group sessions of joint protection education, but these do not translate to long‐term improvements for RA (>24 months). Comprehensive OT had mixed evidence (limited to home OT and an arthritis gloves program), whereas limited evidence was available for qualitative insights, splints and assistive devices, and self‐management for fatigue. Conclusion: Although patient education is promising for self‐managing RA, no strong evidence was found to support OT programs for self‐managing fatigue or patient experience and long‐term effectiveness. More research is required on lived experience, and the long‐term efficacy of self‐management approaches incorporating OT, particularly timing programs to meet the individual's conditional needs (i.e., early or established RA) to build on the few studies to date

    Public and professional involvement in a systematic review investigating the impact of occupational therapy on the self-management of rheumatoid arthritis

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    Introduction: Public and health professional involvement (PHPI) is essential in healthcare research yet uncommonly integrated into systematic reviews. We incorporated and evaluated PHPI in a mixed methods review of occupational therapy for self-management of rheumatoid arthritis (RA). Methods: Public partners were living with or caring for someone with RA. Our steering group comprised two public, two professionals (one occupational therapist, one rheumatologist), and one reviewer who planned the review’s PHPI (August 2021). Involvement was evaluated from public and health professional (PHP) perspectives using a survey and workshops (August–October 2022) exploring reasons for involvement, challenges and learning opportunities. Results: Alongside the steering group, 16 public and 6 professionals were involved throughout the review. Five public refined the search strategy, with three assisting in subsequent review activities. PHPs helped interpret findings during three public ( n = 12) and one professional workshop ( n = 4). Three occupational therapists and one public co-authored (ED) publications. In evaluation, PHPs felt valued and that their involvement was well-integrated. The researchers underestimated the time required for communicating and conducting PHPI in the review. Conclusions: PHPI is worthwhile, feasible and can be integrated within a systematic review. PHP partners considered participation valuable; researchers must prioritise time to prepare and communicate PHPI activities

    Early Virological and Immunological Events in Asymptomatic Epstein-Barr Virus Infection in African Children

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    Epstein-Barr virus (EBV) infection often occurs in early childhood and is asymptomatic. However, if delayed until adolescence, primary infection may manifest as acute infectious mononucleosis (AIM), a febrile illness characterised by global CD8+ T-cell lymphocytosis, much of it reflecting a huge expansion of activated EBV-specific CD8+ T-cells. While the events of AIM have been intensely studied, little is known about how these relate to asymptomatic primary infection. Here Gambian children (14–18 months old, an age at which many acquire the virus) were followed for the ensuing six months, monitoring circulating EBV loads, antibody status against virus capsid antigen (VCA) and both total and virus-specific CD8+ T-cell numbers. Many children were IgG anti-VCA-positive and, though no longer IgM-positive, still retained high virus loads comparable to AIM patients and had detectable EBV-specific T-cells, some still expressing activation markers. Virus loads and the frequency/activation status of specific T-cells decreased over time, consistent with resolution of a relatively recent primary infection. Six children with similarly high EBV loads were IgM anti-VCA-positive, indicating very recent infection. In three of these donors with HLA types allowing MHC-tetramer analysis, highly activated EBV-specific T-cells were detectable in the blood with one individual epitope response reaching 15% of all CD8+ T-cells. That response was culled and the cells lost activation markers over time, just as seen in AIM. However, unlike AIM, these events occurred without marked expansion of total CD8+ numbers. Thus asymptomatic EBV infection in children elicits a virus-specific CD8+ T-cell response that can control the infection without over-expansion; conversely, in AIM it appears the CD8 over-expansion, rather than virus load per se, is the cause of disease symptoms
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