Community engagement with immigrant communities involving health and wellness research: a systematic review protocol towards developing a taxonomy of community engagement definitions, frameworks, and methods.

INTRODUCTION: The importance of community engagement has been established globally in health and wellness research. A certain degree of ambiguity remains, however, regarding the meaning of community engagement, which term has been used for various purposes and implemented in various forms. In this study, we aimed to explore the different definitions of community engagement, discuss the various objectives that have been proposed and uncover the diverse ways this concept has been implemented among researchers working for the betterment of the health and wellness of immigrant communities in host countries. METHODS AND ANALYSIS: Taxonomy is a process for classifying complex and multifaceted matters using logical conceptual domains and dimensions for clearer way of contextualising. We will develop a taxonomy to organise the available literature on community engagement in immigrant health and wellness research in a way that captures user knowledge and understanding of its various meanings and processes. Specific methodological and analytical frameworks for systematic review and taxonomy development will guide each step. We will conduct a comprehensive systematic search in relevant databases, from inception to December 2019, using appropriate keywords followed by snowball search (single-citation tracking, reference lists). Papers will be included if they fall within predefined inclusion criteria (seen as most likely informative on elements pertaining to community engagement) and are written in English, regardless of design (conceptual, qualitative and quantitative). Two reviewers will independently employ two-stage screening (title-abstract screening followed by screening of the full text to determine inclusion). Finally, information that helps to develop taxonomy of the concept and practice of community engagement will be abstracted and used towards taxonomy development, where different levels of stakeholder research team members will be involved. ETHICS AND DISSEMINATION: Ethical approval is not required for this systematic review. We have opted for an integrated knowledge translation or a community-engaged knowledge mobilisation approach where we are engaged with community-based citizen researchers from the inception of our programme. We plan to disseminate the results of our review through meetings with key stakeholders, followed by journal publications and presentations at applicable platforms.

Intravascular neutrophil extracellular traps capture bacteria from the bloodstream during sepsis.

During the systemic inflammatory response of severe sepsis, neutrophils accumulate in the liver microcirculation, but their functional significance is largely unknown. We show that neutrophils migrate to liver sinusoids during endotoxemia and sepsis where they exert protective effects by releasing neutrophil extracellular traps (NETs), which are DNA-based structures that capture and eliminate microbes. NETs released into the vasculature ensnare bacteria from the bloodstream and prevent dissemination. NET production requires platelet-neutrophil interactions and can be inhibited by platelet depletion or disruption of integrin-mediated platelet-neutrophil binding. During sepsis, NET release increases bacterial trapping by 4-fold (beyond the basal level provided by resident intravascular macrophages). Blocking NET formation reduces the capture of circulating bacteria during sepsis, resulting in increased dissemination to distant organs. Thus, NETs ensnare circulating bacteria and provide intravascular immunity that protects against bacterial dissemination during septic infections.