487 research outputs found

    Cc Chemokine Receptor (Ccr)3/Eotaxin Is Followed by Ccr4/Monocyte-Derived Chemokine in Mediating Pulmonary T Helper Lymphocyte Type 2 Recruitment after Serial Antigen Challenge in Vivo

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    Isolated peripheral blood CD4 cells from allergic individuals express CC chemokine receptor (CCR)3 and CCR4 after expansion in vitro. In addition, human T helper type 2 (Th2) cells polarized in vitro selectively express CCR3 and CCR4 at certain stages of activation/differentiation and respond preferentially to the ligands eotaxin and monocyte-derived chemokine (MDC). However, controversy arises when the in vivo significance of this distinct expression is discussed. To address the functional role of CCR3/eotaxin and CCR4/MDC during the in vivo recruitment of Th2 cells, we have transferred effector Th cells into naive mice to induce allergic airway disease. Tracking of these cells after repeated antigen challenge has established that both CCR3/eotaxin and CCR4/MDC axes contribute to the recruitment of Th2 cells to the lung, demonstrating the in vivo relevance of the expression of these receptors on Th2 cells. We have shown that involvement of the CCR3/eotaxin pathway is confined to early stages of the response in vivo, whereas repeated antigen stimulation results in the predominant use of the CCR4/MDC pathway. We propose that effector Th2 cells respond to both CCR3/eotaxin and CCR4/MDC pathways initially, but that a progressive increase in CCR4-positive cells results in the predominance of the CCR4/MDC axis in the long-term recruitment of Th2 cells in vivo

    VCAM-1 and VLA-4 Modulate Dendritic Cell IL-12p40 Production in Experimental Visceral Leishmaniasis

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    Vascular cell adhesion molecule-1 (VCAM-1) interacts with its major ligand very late antigen-4 (VLA-4) to mediate cell adhesion and transendothelial migration of leukocytes. We report an important role for VCAM-1/VLA-4 interactions in the generation of immune responses during experimental visceral leishmaniasis caused by Leishmania donovani. Our studies demonstrate that these molecules play no direct role in the recruitment of leukocytes to the infected liver, but instead contribute to IL-12p40-production by splenic CD8+ dendritic cells (DC). Blockade of VCAM-1/VLA-4 interactions using whole antibody or anti-VCAM-1 Fab′ fragments reduced IL-12p40 mRNA accumulation by splenic DC 5 hours after L. donovani infection. This was associated with reduced anti-parasitic CD4+ T cell activation in the spleen and lowered hepatic IFNγ, TNF and nitric oxide production by 14 days post infection. Importantly, these effects were associated with enhanced parasite growth in the liver in studies with either anti-VCAM-1 or anti-VLA-4 antibodies. These data indicate a role for VCAM-1 and VLA-4 in DC activation during infectious disease

    Nurses' perceptions and experiences of communication in the operating theatre: a focus group interview

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    UNLABELLED: Nurses' perceptions and experiences of communication in the operating theatre: a focus group interview BACKGROUND: Communication programmes are well established in nurse education. The focus of programmes is most often on communicating with patients with less attention paid to inter-professional communication or skills essential for working in specialised settings. Although there are many anecdotal reports of communication within the operating theatre, there are few empirical studies. This paper explores communication behaviours for effective practice in the operating theatre as perceived by nurses and serves as a basis for developing training. METHODS: A focus group interview was conducted with seven experienced theatre nurses from a large London teaching hospital. The interview explored their perceptions of the key as well as unique features of effective communication skills in the operating theatre. Data was transcribed and thematically analysed until agreement was achieved by the two authors. RESULTS: There was largely consensus on the skills deemed necessary for effective practice including listening, clarity of speech and being polite. Significant influences on the nature of communication included conflict in role perception and organisational issues. Nurses were often expected to work outside of their role which either directly or indirectly created barriers for effective communication. Perceptions of a lack of collaborative team effort also influenced communication. CONCLUSION: Although fundamental communication skills were identified for effective practice in the operating theatre, there were significant barriers to their use because of confusion over clarity of roles (especially nurses' roles) and the implications for teamwork. Nurses were dissatisfied with several aspects of communication. Future studies should explore the breadth and depth of this dissatisfaction in other operating theatres, its impact on morale and importantly on patient safety. Interprofessional communication training for operating theatre staff based in part on the key issues identified in this study may help to create clarity in roles and focus attention on effective teamwork and promote clinical safety

    Compartmentalization of total and virus-specific tissue-resident memory CD8+ T Cells in human lymphoid organs

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    Disruption of T cell memory during severe immune suppression results in reactivation of chronic viral infections, such as Epstein Barr virus (EBV) and Cytomegalovirus (CMV). How different subsets of memory T cells contribute to the protective immunity against these viruses remains poorly defined. In this study we examined the compartmentalization of virus-specific, tissue resident memory CD8+ T cells in human lymphoid organs. This revealed two distinct populations of memory CD8+ T cells, that were CD69+CD103+ and CD69+CD103-, and were retained within the spleen and tonsils in the absence of recent T cell stimulation. These two types of memory cells were distinct not only in their phenotype and transcriptional profile, but also in their anatomical localization within tonsils and spleen. The EBV-specific, but not CMV-specific, CD8+ memory T cells preferentially accumulated in the tonsils and acquired a phenotype that ensured their retention at the epithelial sites where EBV replicates. In vitro studies revealed that the cytokine IL-15 can potentiate the retention of circulating effector memory CD8+ T cells by down-regulating the expression of sphingosine-1-phosphate receptor, required for T cell exit from tissues, and its transcriptional activator, Kruppel-like factor 2 (KLF2). Within the tonsils the expression of IL-15 was detected in regions where CD8+ T cells localized, further supporting a role for this cytokine in T cell retention. Together this study provides evidence for the compartmentalization of distinct types of resident memory T cells that could contribute to the long-term protection against persisting viral infections

    BHPR research: qualitative1. Complex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis

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    Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 ♂, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duck”). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?”). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has gone”). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining about”). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes
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