RepoMed (Medizinische Hochschule Hannover)
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Violence against healthcare workers in the middle of a global health crisis:: what is it about policy and what to learn from international comparison?
Get PDFIntroduction Violence against healthcare workers is a global health problem threatening healthcare workforce retention and health system resilience in a fragile post-COVID 'normalisation' period. In this perspective article, we argue that violence against healthcare workers must be made a greater priority. Our novel contribution to the debate is a comparative health system and policy approach. Methods We have chosen a most different systems comparative approach concerning the epidemiological, political, and geographic contexts. Brazil (under the Bolsonaro government) and the United Kingdom (under the Johnson government) serve as examples of countries that were strongly hit by the pandemic in epidemiological terms while also displaying policy failures. New Zealand and Germany represent the opposite. A rapid assessment was undertaken based on secondary sources and country expertise. Results We found similar problems across countries. A global crisis makes healthcare workers vulnerable to violence. Furthermore, insufficient data and monitoring hamper effective prevention, and lack of attention may threaten women, the nursing profession, and migrant/minority groups the most. There were also relevant differences. No clear health system pattern can be identified. At the same time, professional associations and partly the media are strong policy actors against violence. Conclusion In all countries, muchmore involvement from political leadership is needed. In addition, attention to the political dimension and all forms of violence are essential
Reinforcement of cell-mediated immunity driven by tumor-associated Epstein-Barr virus (EBV)-specific T cells during targeted B-cell therapy with rituximab.
Get PDFIntroduction In immunocompromised patients, Epstein-Barr virus (EBV) infection or reactivation is associated with increased morbidity and mortality, including the development of B-cell lymphomas. The first-line treatment consists of reduction of immunosuppression and administration of rituximab (anti-CD20 antibody). Furthermore, the presence of EBV-specific T cells against latent EBV proteins is crucial for the control of EBV-associated diseases. Therefore, in addition to effective treatment strategies, appropriate monitoring of T cells of high-risk patients is of great importance for improving clinical outcome. In this study, we hypothesized that rituximab-mediated lysis of malignant EBV-infected B cells leads to the release and presentation of EBV-associated antigens and results in an augmentation of EBV-specific effector memory T-cell responses. Methods EBV-infected B lymphoblastoid cell lines (B-LCLs) were used as a model for EBV-associated lymphomas, which are capable of expressing latency stage II and III EBV proteins present in all known EBV-positive malignant cells. Rituximab was administered to obtain cell lysates containing EBV antigens (ACEBV). Efficiency of cross-presentation of EBV-antigen by B-LCLs compared to cross-presentation by professional antigen presenting cells (APCs) such as dendritic cells (DCs) and B cells was investigated by in vitro T-cell immunoassays. Deep T-cell profiling of the tumor-reactive EBV-specific T cells in terms of activation, exhaustion, target cell killing, and cytokine profile was performed, assessing the expression of T-cell differentiation and activation markers as well as regulatory and cytotoxic molecules by interferon-γ (IFN-γ) EliSpot assay, multicolor flow cytometry, and multiplex analyses. Results By inhibiting parts of the cross-presentation pathway, B-LCLs were shown to cross-present obtained exogenous ACEBV-derived antigens mainly through major histocompatibility complex (MHC) class I molecules. This mechanism is comparable to that for DCs and B cells and resulted in a strong EBV-specific CD8+ cytotoxic T-cell response. Stimulation with ACEBV-loaded APCs also led to the activation of CD4+ T helper cells, suggesting that longer peptide fragments are processed via the classical MHC class II pathway. In addition, B-LCLs were also found to be able to take up exogenous antigens from surrounding cells by endocytosis leading to induction of EBV-specific T-cell responses although to a much lesser extent than cross-presentation of ACEBV-derived antigens. Increased expression of activation markers CD25, CD71 and CD137 were detected on EBV-specific T cells stimulated with ACEBV-loaded APCs, which showed high proliferative and cytotoxic capacity as indicated by enhanced EBV-specific frequencies and increased secretion levels of cytotoxic effector molecules (e.g. IFN-γ, granzyme B, perforin, and granulysin). Expression of the regulatory proteins PD-1 and Tim-3 was induced but had no negative impact on effector T-cell functions. Conclusion In this study, we showed for the first time that rituximab-mediated lysis of EBV-infected tumor cells can efficiently boost EBV-specific endogenous effector memory T-cell responses through cross-presentation of EBV-derived antigens. This promotes the restoration of antiviral cellular immunity and presents an efficient mechanism to improve the treatment of CD20+ EBV-associated malignancies. This effect is also conceivable for other therapeutic antibodies or even for therapeutically applied unmodified or genetically modified T cells, which lead to the release of tumor antigens after specific cell lysis
Third SARS-CoV-2 vaccination and breakthrough infections enhance humoral and cellular immunity against variants of concern
Get PDFIntroduction SARS-CoV-2 vaccination is the leading strategy to prevent severe courses after SARS-CoV-2 infection. In our study, we analyzed humoral and cellular immune responses in detail to three consecutive homologous or heterologous SARS-CoV-2 vaccinations and breakthrough infections. Methods Peripheral blood samples of n=20 individuals were analyzed in the time course of three SARS-CoV-2 vaccinations and/or breakthrough infection. S1-, RBD-, S2- and N-specific IgG antibodies were quantified using Luminex-based multiplex assays and electrochemiluminescence multiplex assays for surrogate neutralization in plasma. Changes in cellular immune components were determined via flow cytometry of whole blood samples. Results All individuals (n=20) responded to vaccination with increasing S1-/RBD-/S2-specific IgG levels, whereas specific plasma IgA displayed individual variability. The third dose increased antibody inhibitory capacity (AIC) against immune-escape variants Beta and Omicron BA.1 independently of age. The mRNA-primed vaccination induced IgG and IgA immunity more efficiently, whereas vector-primed individuals displayed higher levels of memory T and B cells. Vaccinees showed SARS-CoV-2-specific T cell responses, which were further improved and specified after Omicron breakthrough infections in parallel to the appearance of new variant-specific antibodies. Discussion In conclusion, the third vaccination was essential to increase IgG levels, mandatory to boost AIC against immune-escape variants, and induced SARS-CoV-2-specific T cells. Breakthrough infection with Omicron generates additional spike specificities covering all known variants
Evaluation of a multimodal pain therapy approach with relapse prophylaxis for back pain (MMS-RFP study): a study protocol for a cluster randomised controlled trial
Get PDFIntroduction The need for an interdisciplinary multimodal approach to the treatment of back pain has already been demonstrated by various studies. However, when considering the periods of incapacity to work in the longitudinal course after the multimodal pain therapy (MPT), limits in terms of its sustainable effect become clear. Patients who receive MPT subsequently return to standard outpatient care, which is associated with a risk of relapse. A 12-month relapse prophylaxis (RP) programme, intended to follow a 4-week MPT, was developed to help patients make the transition to health-conscious and physically active behaviour in everyday life and to identify and prevent impending relapses at an early stage. The evaluation, based on a cluster randomised controlled trial, seeks to provide information on the benefits of early and intensive RP as part of MPT, examine whether it is cost effective, reduces the days of incapacity to work and increases functional capacity, as well as to examine other parameters. Methods and analysis The study population comprises members of a regional statutory health insurance fund in Germany, who are ≤62 years old, gainfully employed and have been incapacitated for work for at least 21 days due to a diagnosis of back pain. Over a recruitment period of 24 months, a maximum of 368 individuals can potentially be included in the MPT. The intervention group (IG) and control group (CG) will both receive MPT, after randomisation IG will receive RP and CG will receive no further therapy or support as part of the trial. The evaluation is carried out on the following levels: structural, process and results quality. Cost effectiveness is also assessed by means of a health economic evaluation. In addition to the collection of qualitative and quantitative primary data, claims data from the regional health insurance fund are also included in the analysis. Ethics and dissemination This study has received approval by the ethics committee of the Hannover Medical School (reference number: 8548_BO_S_2019). The study results will be disseminated in national and international journals and conference presentations. Trial registration number DRKS00017654
