Abstract
A safe and effective vaccine adjuvant is important in modern vaccines. Various Chinese herbal polysaccharides can activate the immune system. Cistanche deserticola (CD) is a traditional Chinese herb and an adjuvant candidate. Here, we confirmed that water-extractable polysaccharides of CD (WPCD) could modulate immune responses in vitro and in vivo. In a dose-dependent manner, WPCD significantly promoted the maturation and function of murine marrow-derived dendritic cells (BM-DCs) through up-regulating the expression levels of MHC-II, CD86, CD80, and CD40, allogenic T cell proliferation, and the yields of IL-12 and TNF-α via toll-like receptor4 (TLR4), as indicated by in vitro experiments. In addition, its immunomodulatory activity was also observed in mice. WPCD effectively improved the titers of IgG, IgG1 and IgG2a and markedly enhanced the proliferation of T and B cells, the production of IFN-γ and IL-4 in CD4+ T cells and the expression level of IFN-γ in CD8+ T cells better than Alum. Furthermore, WPCD could markedly up-regulate the expression levels of CD40 and CD80 on DCs in spleen and down-regulate the Treg frequency. The study suggests that polysaccharides of Cistanche deserticola are a safe and effective vaccine adjuvant for eliciting both humoral immunity and cellular immunity by activating DCs via TLR4 signaling pathway.
Highlights
Vaccines are important for controlling or preventing diseases
We examined the specific immune response to ovalbumin (OVA) in mice treated with water-extractable polysaccharides of CD (WPCD), including titers of IgG, IgG1 and IgG2a subclass, T- and B- proliferation, and the production of cytokine
The cells gated with SSC and FSC showed that the treatment with different doses of WPCD did not change the morphology of BM-DCs
Summary
Vaccines are important for controlling or preventing diseases. Newly generated and current developing vaccines are highly purified recombinant antigens with a higher safety, but purified antigens cannot stimulate a satisfactory immune response compared with attenuated or inactivated pathogen preparations. With the aid of adjuvants, vaccines can induce persistent immune responses [1,2]. Various adjuvants have been identified and extensively studied. These adjuvants endow vaccines with several advantages, including decreasing the required amount of antigens, minimizing the number of immunizations required for normal immune responses, and inducing more rapid, broader, and stronger immune responses [3,4,5]. Many potent adjuvants have been developed, such as lipolysaccharide (LPS) and Freund’s complete adjuvant (FCA), they are not widely applied due to their toxicity. More effective and safer adjuvants should be developed to promote the better prophylactic and therapeutic vaccines against infectious and noninfectious diseases
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
