Cistanche deserticola polysaccharide- functionalized dendritic fibrous nano-silica -based adjuvant for H9N2 oral vaccine enhance systemic and mucosal immunity in chickens.

Avian influenza virus subtype H9N2 has the ability to infect birds and humans, further causing significant losses to the poultry industry and even posing a great threat to human health. Oral vaccine received particular interest for preventing majority infection due to its ability to elicit both mucosal and systemic immune responses, but their development is limited by the bad gastrointestinal (GI) environment, compact epithelium and mucus barrier, and the lack of effective mucosal adjuvants. Herein, we developed the dendritic fibrous nano-silica (DFNS) grafted with Cistanche deserticola polysaccharide (CDP) nanoparticles (CDP-DFNS) as an adjuvant for H9N2 vaccine. Encouragingly, CDP-DFNS facilitated the proliferation of T and B cells, and further induced the activation of T lymphocytes in vitro. Moreover, CDP-DFNS/H9N2 significantly promoted the antigen-specific antibodies levels in serum and intestinal mucosal of chickens, indicating the good ability to elicit both systemic and mucosal immunity. Additional, CDP-DFNS facilitate the activation of CD4 + and CD8 + T cells both in spleen and intestinal mucosal, and the indexes of immune organs. This study suggested that CDP-DFNS may be a new avenue for development of oral vaccine against pathogens that are transmitted via mucosal route.

Rosa laevigata Polysaccharides Ameliorate Dextran Sulfate Sodium-Induced Ulcerative Colitis of Beagles through Regulating Gut Microbiota.

Rosa laevigata Michx. polysaccharides (RLP) have been demonstrated to possess antioxidant and anti-inflammatory properties. However, the mechanisms and efficacy of these polysaccharide components in preventing ulcerative colitis (UC) remain to be elucidated. The efficacy and mechanisms of RLP were investigated in a study that utilized healthy adult beagles to establish a UC model, considering the similarities in gut microbiota between humans and dogs. In the study, the beagle model induced by sodium dextran sulfate exhibited typical symptoms of ulcerative colitis, such as weight loss and diarrhea. All these symptoms and changes were significantly ameliorated through oral supplementation of RLP. Additionally, microbial community analysis based on the 16S rDNA gene revealed that RLP alleviated UC by increasing the abundance of beneficial bacteria and reducing the abundance of harmful bacteria. In conclusion, our study has provided that RLP effectively alleviated colitis by preserving the intestinal barrier and regulating the gut microbiota composition.

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.

Structure analysis and antimutagenic activity of a novel salt-soluble polysaccharide from Auricularia polytricha.

BACKGROUND: Auricularia polytricha is known to be a highly nutritious foodstuff. We report here the purification, structure characterization and antimutagenic activity in vivo of a 0.9% NaCl solution-soluble polysaccharide (SSP) from the mycelia of A. polytricha. RESULTS: Analysis by high-performance liquid chromatography coupled to a TSK-G5000PWXL column and gel filtration chromatography on Sephacryl S-400 HR indicated that SSP is homogeneous with an average molecular weight of about 9.30 × 10(5) Da. The structure of SSP was revealed by chemical methods, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. Results indicated that SSP is a glucan consisting of a1,3-ß-glucan, 1,6-α-glucan, 1,4-α-glucan and 1,3-α-glucan backbone with a single 1,6-α-d-glucopyranosyl side-branching unit on every nine residues, on average, along the main chain. Atomic force microscopy indicates the presence of macromolecular species in morphology and shows a clear association of prolate particle. Meanwhile, SSP was found to significantly preventing micronuclei in polychromatic erythrocytes and reticulocytes of mice (P < 0.01). CONCLUSION: These results indicate that polysaccharide SSP from A. polytricha exhibits antimutagenic activity against the in vivo DNA-damaging effect of the indirectly acting alkylating agent cyclophosphamide.