The Cell Adhesion Molecule “CAR” and Sialic Acid on Human Erythrocytes Influence Adenovirus In Vivo Biodistribution

Although it has been known for 50 years that adenoviruses (Ads) interact with erythrocytes ex vivo, the molecular and structural basis for this interaction, which has been serendipitously exploited for diagnostic tests, is unknown. In this study, we characterized the interaction between erythrocytes and unrelated Ad serotypes, human 5 (HAd5) and 37 (HAd37), and canine 2 (CAV-2). While these serotypes agglutinate human erythrocytes, they use different receptors, have different tropisms and/or infect different species. Using molecular, biochemical, structural and transgenic animal-based analyses, we found that the primary erythrocyte interaction domain for HAd37 is its sialic acid binding site, while CAV-2 binding depends on at least three factors: electrostatic interactions, sialic acid binding and, unexpectedly, binding to the coxsackievirus and adenovirus receptor (CAR) on human erythrocytes. We show that the presence of CAR on erythrocytes leads to prolonged in vivo blood half-life and significantly reduced liver infection when a CAR-tropic Ad is injected intravenously. This study provides i) a molecular and structural rationale for Ad–erythrocyte interactions, ii) a basis to improve vector-mediated gene transfer and iii) a mechanism that may explain the biodistribution and pathogenic inconsistencies found between human and animal models

Advancing a Conceptual Model of Evidence-Based Practice Implementation in Public Service Sectors

Implementation science is a quickly growing discipline. Lessons learned from business and medical settings are being applied but it is unclear how well they translate to settings with different historical origins and customs (e.g., public mental health, social service, alcohol/drug sectors). The purpose of this paper is to propose a multi-level, four phase model of the implementation process (i.e., Exploration, Adoption/Preparation, Implementation, Sustainment), derived from extant literature, and apply it to public sector services. We highlight features of the model likely to be particularly important in each phase, while considering the outer and inner contexts (i.e., levels) of public sector service systems

Exploring non-participation in primary care physical activity interventions: PACE-UP trial interview findings

Background: Trials in primary care to increase physical activity (PA) typically experience poor recruitment rates and may not recruit those with lower PA levels and who are most in need of the intervention. Despite the well-publicised benefits of physical activity, the majority of adults in the UK remain inactive and therefore at greater risk of many health problems. Our aim was to investigate the reasons for non-participation in the PACE-UP trial, which is a primary care pedometer based walking intervention. This is important for successful recruitment and retention in future PA trials and programmes. Method: We conducted semi-structured audio-recorded telephone interviews with thirty 45-75 year olds purposively sampled from those declining participation in the PACE-UP trial. Recruitment continued until data saturation and a demographically balanced sample was achieved. Interviews were transcribed verbatim, coded and subjected to thematic analysis. Results: Interviewees supported walking as suitable exercise for most people in this age group, recognised the importance of this type of research and general practice as an appropriate setting. Key reasons for declining were: the perception of being already ‘too active’; existing medical conditions; work; travel and other commitments. Less frequently cited reasons included reluctance to be randomised, the intervention’s duration, wearing a pedometer, perceived inappropriateness of trial literature and a preference for a different kind of PA or for a group activity. Conclusions: Whilst most interviewees perceived themselves to be sufficiently active, an important minority did not participate due to existing medical conditions and other commitments. Recruitment to future PA trials might be improved by tailoring activity to compensate for medical problems, and adapting PA interventions to fit around work and travel commitments. Ensuring patient literature is succinct and inclusive and equipment is user-friendly is important. Primary care is seen as an appropriate setting for PA trials and programmes.The PACE-UP trial was funded by the National Institute for Health Research Health Technology Assessment (NIHR HTA) Programme (project number HTA 10/32/02 ISRCTN42122561)