Sub-Nucleocapsid Nanoparticles: A Nasal Vaccine against Respiratory Syncytial Virus

Background: Bronchiolitis caused by the respiratory syncytial virus (RSV) in infants less than two years old is a growing public health concern worldwide, and there is currently no safe and effective vaccine. A major component of RSV nucleocapsid, the nucleoprotein (N), has been so far poorly explored as a potential vaccine antigen, even though it is a target of protective anti-viral T cell responses and is remarkably conserved between human RSV A and B serotypes. We recently reported a method to produce recombinant N assembling in homogenous rings composed of 10–11 N subunits enclosing a bacterial RNA. These nanoparticles were named sub-nucleocapsid ring structure (N SRS). Methodology and Principal Findings: The vaccine potential of N SRS was evaluated in a well-characterized and widely acknowledged mouse model of RSV infection. BALB/c adult mice were immunized intranasally with N SRS adjuvanted with the detoxified E. coli enterotoxin LT(R192G). Upon RSV challenge, vaccinated mice were largely protected against virus replication in the lungs, with a mild inflammatory lymphocytic and neutrophilic reaction in their airways. Mucosal immunization with N SRS elicited strong local and systemic immunity characterized by high titers of IgG1, IgG2a and IgA anti-N antibodies, antigen-specific CD8+ T cells and IFN-c-producing CD4+ T cells. Conclusions/Significance: This is the first report of using nanoparticles formed by the recombinant nucleocapsid protein as an efficient and safe intra-nasal vaccine against RSV

Dose-Response Association of Tai Chi and Cognition among Community-Dwelling Older Adults: A Systematic Review and Meta-Analysis

Previous studies indicated that Tai Chi might be an effective way to improve or prevent cognitive impairments in older populations. However, existing research does not provide clear recommendations about the optimal dose of Tai Chi practice, which is the most effective in improving cognitive function in older adults. The purpose of this systematic review and meta-analysis was to investigate the dose–response relationship between Tai Chi and cognition in community-dwelling older adults. A total of 16 studies with 1121 subjects were included in this study. Meta-regression analyses of Tai Chi duration (Tai Chi session duration, Tai Chi practice duration per week, study duration, and Tai Chi practice duration for the entire study) on the study effect size (ES) were performed to examine the dose–response association of Tai Chi and cognition. The results showed that there was a positive effect of Tai Chi on cognitive function, but there were no statistically significant dose duration effects on cognition. The findings suggest that Tai Chi has beneficial effects on cognitive function, but a longer duration was not associated with larger effects. In order to establish evidence-based clinical interventions using Tai Chi, future research should clearly demonstrate intervention protocol, particularly the style and intensity of Tai Chi