Cistanche deserticola polysaccharide-functionalized dendritic fibrous nano-silica as oral vaccine adjuvant delivery enhancing both the mucosal and systemic immunity.

Oral vaccines are a safe and convenient alternative to injected vaccines and have great potential to prevent major infectious diseases. However, the harsh gastrointestinal (GI) environment, mucus barriers, low immunogenicity, and lack of effective and safe mucosal adjuvants are the major challenges for oral vaccine delivery. In recent years, nanoparticle-based strategies have become attractive for improving oral vaccine delivery. Here, the dendritic fibrous nano-silica (DFNS) grafted with Cistanche deserticola polysaccharide (CDP) nanoparticles (CDP-DFNS) were prepared and investigated how to impact the immune responses. CDP-DFNS facilitated the antigen uptake in mouse bone marrow-derived dendritic cells (BMDCs), and induce the activation of DCs in vitro. Furthermore, in vivo experiments, the result showed that the uptake efficiency by Peyer's patches (PPs) of CDP-DFNS/BSA was the best. And CDP-DFNS/BSA then significantly activated the DCs in lamina propria (LP), and T/B cells in PPs and mesenteric lymph nodes (MLNs). Moreover, the memory T cell responses in later period of vaccination was stronger than other groups. In addition, CDP-DFNS/BSA enhanced BSA-specific antibody IgG, IgA production, and SIgA secretion, was effective at inducing a strong mixed Th1/Th2 response and mucosal antibody responses. These results indicated that CDP-DFNS deserves further consideration as an oral vaccine adjuvant delivery system.

Can mental imagery boost the effect of the positive cognitive bias modification of interpretation (CBM-I) on interpretation bias and memory bias?

BACKGROUND AND OBJECTIVES: Cognitive bias modification of interpretation (CBM-I) has been widely used and yielded mixed results. This experiment explored the unique role of mental imagery in positive CBM-I. METHODS: 60 participants (M = 23.13, SD = 1.04) were randomly assigned to a imagery-based positive CBM-I group (imagery group) and a conventional verbal-based positive CBM-I group (control group). The imagery group received additional practice in generating mental imagery and were instructed to fully focus on the imagery during the formal training. The dependent variables included interpretation bias (probe latencies and similarity ratings for recognition task), memory bias, and intrusive memory. RESULTS: (1) For the positive probe scenario, the reaction time of the two groups was shorter in the posterior five blocks than the anterior five blocks. However, the difference in latency between pre- and post- training for the imagery group was larger than that of the control group; (2) For the recognition task, the positive target statement score was significantly higher, while the negative one was significantly lower for the imagery group than that of the control group (3) The imagery group (vs. control); showed more beneficial effects on memory bias. LIMITATIONS: The limitations consisted of the difference in time of the manipulation between the two groups, the richness of the imagery operationalization, generalizability, and the lack of pre-manipulation of interpretation bias assessments. CONCLUSIONS: The imagery-based CBM-I led to more positive interpretation biases, less negative interpretations, and more positive memory biases, indicating that mental imagery can boost the effect of the positive CBM-I.

Supplementation of Alhagi honey polysaccharides contributes to the improvement of the intestinal immunity regulating the structure of intestinal flora in mice.

Alhagi honey polysaccharides (AH), a main active component of Alhagi honey, are known to possess excellent pharmacological activities and have been widely used as dietary supplements in traditional Chinese medicine for thousands of years. This study is aimed to investigate the heath effect of AH on murine intestinal mucosal immune function and composition of the gut microbiome. ICR mice received daily intragastric administration of AH (three dosages, 200 mg kg-1, 400 mg kg-1, and 800 mg kg-1) or saline for 7 consecutive days. Results indicated an improvement in the intestinal barrier function through increases in secretory immunoglobulin A (sIgA) and ß-defensins. Simultaneously, AH also significantly stimulated IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α cytokine secretion as compared to the control samples. Moreover, hematoxylin and eosin staining showed that AH enhanced the number of intraepithelial lymphocytes (IELs) in the small intestine. An obvious increase in the ratio of IgA+ cells of AH-treatment samples in the lamina propria was also detected by immunohistochemical staining. In addition, the CD3+, CD4+ and CD8+ T-cell ratio in mesenteric lymph nodes and Peyer's patches in the AH-treatment was significantly higher than that in the control group. Furthermore, 16S rDNA gene sequencing was used to monitor the dynamic changes in the gut microbiota. The result revealed that AH significantly increased the indexes of Shannon and obviously decreased the indexes of Simpson, suggesting the enhancement of the diversity and richness of the intestinal microbiome. Moreover, AH modulated the gut microbiome via increasing the abundance of probiotics and decreasing the levels of pathogenic bacteria. In summary, these results indicated that AH could be used as a prebiotic to enhance murine intestinal mucosal immunity and to modulate the gut microbiome.