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This paper first provides that Chinese yam polysaccharide (CYP) is encapsulated by PLGA using a double emulsion solvent evaporation method and aims to screen the optimal preparation of CYP-PLGA nanoparticles (CYPP) using response surface methodology (RSM). The volume ratio of the internal water phase to the organic phase (W1:O), the volume ratio of the primary emulsion to the external water phase (PE:W2) and the concentration of Poloxamer 188 (F68) are deemed key variables for the encapsulation efficiency of CYPP. The results demonstrated that the data were accurately fitted into the RSM model. According to the RSM, the optimal scheme was a volume ratio of W1:O of 1:9, a volume ratio of PE: W2 of 1:10 and a concentration of F68 (W/V) of 0.7%. TEM and SEM images demonstrated that the nanoparticles had a spherical shape and smooth surface. The CYP and CYPP in vitro release studies demonstrated that the CYPP showed a release rate 53.41% lower than the release rate of CYP after 48h. The result of pro-proliferation and flow cytometry emerged that the CYPP were more effective compared with the free CYP and blank PLGA nanoparticles in promoting lymphocyte proliferation and triggering the transformation of T lymphocytes into Th cells., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Liposome-based vaccine delivery systems are known to enhance immune responses. Ganoderma lucidum polysaccharides (GLP) have been widely studied as immunomodulator and it could be as inducers of strong immune responses. In the research, GLP and ovalbumin (OVA) were encapsulated into liposome as vaccine and inoculated to mice. The magnitude and kinetics of the humoral and cellular immune responses were investigated. The results showed that GLP-OVA-loaded liposomes (GLPL/OVA) could induce more powerful antigen-specific immune responses than each single-component formulation. Mice immunized with GLPL/OVA displayed higher antigen-specific IgG antibodies, better splenocytes proliferation, higher cytokine secretion by splenocytes and significant activation of CD3+CD4+ and CD3+CD8+ T cells. Thus the GLPL/OVA formulation produced a heightened humoral and cellular immune response, with an overall Th1 bias. Enhanced immune responses elicited by the GLPL/OVA formulation might be attributed to effective activation and mature of DC in draining lymph nodes. Overall, these findings indicate that GLPL have the potential to enhance immune responses as vaccine delivery systems., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) has been approved by the US Food and Drug Administration and has frequently been used to develop potential vaccine delivery systems. The immunoregulation and immunopotentiation of Chinese yam polysaccharide (CYP) have been widely demonstrated. In the current study, cell uptake mechanisms in dendritic cells (DCs) were monitoredin vitrousing confocal laser scanning microscopy, transmission electron microscopy, and flow cytometry. To study a CYP-PLGA nanoparticle-adjuvanted delivery system, CYP and ovalbumin (OVA) were encapsulated in PLGA nanoparticles (CYPPs) to act as a vaccine, and the formulation was tested in immunized mice. The CYPPs more easily underwent uptake by DCsin vitro, and CYPP/OVA could stimulate more effective antigen-specific immune responses than any of the single-component formulationsin vivo. Mice immunized using CYPP/OVA exhibited more secretion of OVA-specific IgG antibodies, better proliferation, and higher cytokine secretion by splenocytes and significant activation of CD3+CD4+and CD3+CD8+T cells. Overall, the CYPP/OVA formulation produced a stronger humoral and cellular immune response and a mixed Th1/Th2 immune response with a greater Th1 bias in comparison with the other formulations. In conclusion, the data demonstrate that the CYPP-adjuvanted delivery system has the potential to strengthen immune responses and lay the foundation for novel adjuvant design. [ABSTRACT FROM AUTHOR]

In previous researches, the results showed that Lycium barbarum polysaccharides (LBP) encapsulated with liposome could enhance the immune activity of LBP. Therefore, the present study was designed to investigate the effects of LBPL on spleen lymphocytes and macrophages of mice in vitro and evaluate the immunological adjuvant activity of PCV2 vaccine in vivo . The results showed that LBPL could significantly promote splenocyte proliferation synergistically with PHA or LPS, increase the ratio of CD4 + to CD8 + T cells and promote the cytokine secretion of macrophages; enhance PCV2-specific IgG antibody responses, promote Th1 cytokines (IFN-γ and TNF-a) and Th2 cytokine (IL-4) secretion. The histomorphological observation of spleen demonstrated that LBPL as a vaccine adjuvant also has good improvement and stimulating effect on the immune organ. [ABSTRACT FROM AUTHOR]

The activation of murine peritoneal macrophages by Ganoderma lucidum polysaccharides liposomes (GLPL) was investigated in vitro. After treatment with GLPL, the changes of the nitric oxide (NO) secretion and iNOS (inducible nitric oxide synthase) activity were evaluated. The results showed that NO production and iNOS activity of macrophages were enhanced compared to GLP and BL group. In addition, both the phagocytic activity and levels of cytokines IL-1β, TNF-α and IFN-γ were enhanced in the peritoneal macrophages of mice by stimulation of GLPL. The expression of the major histocompatibility complex class II molecule (MHC II) on the surface of peritoneal macrophages significantly increased. These indicated that GLPL could enhance the activation of peritoneal macrophages and their potential for use as a delivery system of GLP. [ABSTRACT FROM AUTHOR]