27 research outputs found
A mammalian cell based FACS-panning platform for the selection of HIV-1 envelopes for vaccine development
An increasing number of broadly neutralizing monoclonal antibodies (bnMAb) against the HIV-1 envelope (Env) protein has been discovered recently. Despite this progress, vaccination efforts with the aim to re-elicit bnMAbs that provide protective immunity have failed so far. Herein, we describe the development of a mammalian cell based FACS-panning method in which bnMAbs are used as tools to select surface-exposed envelope variants according to their binding affinity. For that purpose, an HIV-1 derived lentiviral vector was developed to infect HEK293T cells at low multiplicity of infection (MOI) in order to link Env phenotype and genotype. For proof of principle, a gp145 Env model-library was established in which the complete V3 domain was substituted by five strain specific V3 loop sequences with known binding affinities to nMAb 447-52D, respectively. Env genes were recovered from selected cells by PCR, subcloned into a lentiviral vector (i) to determine and quantify the enrichment nMAb binders and (ii) to generate a new batch of transduction competent particles. After 2 selection cycles the Env variant with highest affinity was enriched 20-fold and represented 80% of the remaining Env population. Exploiting the recently described bnMAbs, this procedure might prove useful in selecting Env proteins from large Env libraries with the potential to elicit bnMAbs when used as vaccine candidates
Effectiveness of a community-based osteoporosis education and self-management course: a wait list controlled trial
Summary : Osteoporosis is an increasing burden on individuals and health resources. The Osteoporosis Prevention and Self-Management Course (OPSMC) was designed to assist individuals to prevent and manage osteoporosis; however, it had not been evaluated in an Australian setting. This randomised controlled trial showed that the course increased osteoporosis knowledge.Introduction and hypothesis : Osteoporosis is a major and growing public health concern. An OPSMC was designed to provide individuals with information and skills to prevent or manage osteoporosis, but its effectiveness has not previously been evaluated. This study aimed to determine whether OPSMC attendance improved osteoporosis knowledge, self-efficacy, self-management skills or behaviour.Materials and methods : Using a wait list randomised controlled trial design, 198 people (92% female) recruited from the community and aged over 40 (mean age = 63) were randomised into control (n = 95) and intervention (n = 103) groups. The OPSMC consists of four weekly sessions which run for 2 h and are led by two facilitators. The primary outcome were osteoporosis knowledge, health-directed behaviour, self-monitoring and insight and self-efficacy.Results : The groups were comparable at baseline. At 6-week follow-up, the intervention group showed a significant increase in osteoporosis knowledge compared with the control group; mean change 3.5 (p < 0.001) on a measure of 0–20. The intervention group also demonstrated a larger increase in health-directed behaviour, mean change 0.16 (p < 0.05), on a measure of 0–6.Conclusion : The results indicate that the OPSMC is an effective intervention for improving understanding of osteoporosis and some aspects of behaviour in the short term.<br /
Parent, Teacher, and Student Perspectives on How Corrective Lenses Improve Child Wellbeing and School Function
OBJECTIVES: Up to 20% of school-age children have a vision problem identifiable by screening, over 80% of which can be corrected with glasses. While vision problems are associated with poor school performance, few studies describe whether and how corrective lenses affect academic achievement and health. Further, there are virtually no studies exploring how children with correctable visual deficits, their parents, and teachers perceive the connection between vision care and school function. METHODS: We conducted a qualitative evaluation of Vision to Learn (VTL), a school-based program providing free corrective lenses to low-income students in Los Angeles. Nine focus groups with students, parents, and teachers from three schools served by VTL explored the relationships between poor vision, receipt of corrective lenses, and school performance and health. RESULTS: Twenty parents, 25 teachers, and 21 students from three elementary schools participated. Participants described how uncorrected visual deficits reduced students’ focus, perseverance, and class participation, affecting academic functioning and psychosocial stress; how receiving corrective lenses improved classroom attention, task persistence, and willingness to practice academic skills; and how serving students in school rather than in clinics increased both access to and use of corrective lenses. CONCLUSIONS FOR PRACTICE: Corrective lenses may positively impact families, teachers, and students coping with visual deficits by improving school function and psychosocial wellbeing. Practices that increase ownership and use of glasses, such as serving students in school, may significantly improve both child health and academic performance
Elicitation of Robust Tier 2 Neutralizing Antibody Responses in Nonhuman Primates by HIV Envelope Trimer Immunization Using Optimized Approaches
The development of stabilized recombinant HIV envelope trimers that mimic the virion surface molecule has increased enthusiasm for a neutralizing antibody (nAb)-based HIV vaccine. However, there is limited experience with recombinant trimers as immunogens in nonhuman primates, which are typically used as a model for humans. Here, we tested multiple immunogens and immunization strategies head-to-head to determine their impact on the quantity, quality, and kinetics of autologous tier 2 nAb development. A bilateral, adjuvanted, subcutaneous immunization protocol induced reproducible tier 2 nAb responses after only two immunizations 8 weeks apart, and these were further enhanced by a third immunization with BG505 SOSIP trimer. We identified immunogens that minimized non-neutralizing V3 responses and demonstrated that continuous immunogen delivery could enhance nAb responses. nAb responses were strongly associated with germinal center reactions, as assessed by lymph node fine needle aspiration. This study provides a framework for preclinical and clinical vaccine studies targeting nAb elicitation