Design of hepadnavirus core protein-based chimeric virus-like particles carrying epitopes from respiratory syncytial virus.

Respiratory syncytial virus (RSV) is one of the most important pathogens causing respiratory tract infection in humans, especially in infants and the elderly. The identification and structural resolution of the potent neutralizing epitopes on RSV fusion (F) protein enable an "epitope-focused" vaccine design. However, the display of RSV F epitope II on the surface of the widely-used human hepatitis B virus core antigen (HBcAg) has failed to induce neutralizing antibody response in mice. Here, we used the hepadnavirus core protein (HcAg) from different mammalian hosts as scaffolds to construct chimeric virus-like particles (VLPs) presenting the RSV F epitope II. Mouse immunization showed that different HcAg-based chimeric VLPs elicited significantly different neutralizing antibody responses, among which the HcAg derived from roundleaf bat (RBHcAg) is the most immunogenic. Furthermore, RBHcAg was used as the scaffold platform to present multiple RSV F epitopes, and the immunogenicity was further improved in comparison to that displaying a single epitope II. The designed RBHcAg-based multiple-epitope-presenting VLP formulated with MF59-like adjuvant elicited a potent and balanced Th1/Th2 immune response, and offered substantial protection in mice against the challenge of live RSV A2 virus. The designed chimeric VLPs may serve as the potential starting point for developing epitope-focused vaccines against RSV. Our study also demonstrated that RBHcAg is an effective VLP carrier for presenting foreign epitopes, providing a promising platform for epitope-focused vaccine design.

[Effects of B-GOS on cognitive behavior and depression of transgenic mice with Alzheimer's disease].

Objective: To investigate the effects of novel BimunoGalactooligosaccharides (B-GOS) on cognitive behavior and depression of APP/PS1/tau Alzheimer's disease transgenic mice. Methods: Five-month-old male APP/PS1/tau AD transgenic mice and C57BL/6J control mice were divide into C57+Vehicle group, C57+B-GOS group, APP/PS1/tau+Vehicle group and APP/PS1/tau+B-GOS group, with 10 mice in each group. After continuous administration of B-GOS for 5 months, the cognitive behavior and depressive mood changes of mice in each group were detected by open field experiment, new object recognition experiment, Y maze experiment, Morris water maze experiment, tail suspension test, forced swimming test and conditioned fear experiment, respectively. Results: ①Open field experiment: the percentage of activity time in the central area of open field in APP/PS1/tau+Vehicle group mice was significantly lower than that in C57+Vehicle group mice (P＜0.01), and was remarkably increased after B-GOS intervention (P＜0.05). ② New object recognition experiment: the new object recognition index (NOI) of APP/PS1/tau+Vehicle group mice was significantly lower than that of C57+Vehicle group mice (P＜0.01), and was observably increased after B-GOS intervention (P＜0.05). ③ Y maze experiment: the spontaneous alternation correct rate of APP/PS1/tau+Vehicle group mice was notably lower than that in C57+Vehicle group (P＜0.01), and was distinctly increased after B-GOS intervention (P＜0.01). ④ Classical water maze experiment: the escape latency of APP/PS1/tau+Vehicle group mice on the 4th and 5th days was significantly longer than that of C57+Vehicle group mice (P＜0.01), which was markedly shortened after B-GOS intervention (P＜0.05). During the space exploration phase, the percentage of swimming time in the target quadrant and the times of crossing the platform in APP/PS1/tau+Vehicle group mice were significantly lower than those in C57+Vehicle group mice (P＜0.01), which were notably increased after B-GOS intervention (P＜0.01). ⑤ Tail suspension test and forced swimming test: the percentage of immobility time in APP/PS1/tau+Vehicle group mice was dramatically higher than that in C57+Vehicle group mice (P＜0.01), and was obviously reduced after B-GOS intervention (P＜ 0.01). ⑥ Conditioned fear experiment: before conditioned stimulus (CS), the freezing ratio of mice in each group had no statistical difference (P＞0.05). After CS, the freezing ratio of APP/PS1/tau+Vehicle group mice was significantly lower than that of C57+Vehicle group mice (P＜0.01), and was notably increased after B-GOS intervention (P＜0.01). Conclusion: B-GOS could reverse the cognitive behavioral impairment of APP/PS1/tau mice and alleviate their depression to a large extent.

Color fringe-projected technique for measuring dynamic objects based on bidimensional empirical mode decomposition.

A triple-frequency color fringe-projected technique is presented to measure dynamic objects. Three fringe patterns with a carrier frequency ratio of 1:3:9 are encoded in red, green, and blue channels of a color fringe pattern and projected onto an object's surface. Bidimensional empirical mode decomposition is used for decoupling the cross talk among color channels and for extracting the fundamental frequency components of the three fringe patterns. The unwrapped phase distribution of the high-frequency fringe is retrieved by a three-step phase unwrapping strategy to recover the object's height distribution. Owing to its use of only a single snapshot, the technique is suitable for measuring dynamically changing objects with large discontinuity or spatially isolated surfaces.