Protein-bound polysaccharide activates dendritic cells and enhances OVA-specific T cell response as vaccine adjuvant.

ABSTRACT: Protein-bound polysaccharide-K (PSK) is a hot water extract from Trametes versicolor mushroom. It has been used traditionally in Asian countries for its immune stimulating and anti-cancer effects. We have recently found that PSK can activate Toll-like receptor 2 (TLR2). TLR2 is highly expressed on dendritic cells (DC), so the current study was undertaken to evaluate the effect of PSK on DC activation and the potential of using PSK as a vaccine adjuvant. In vitro experiments using mouse bone marrow-derived DC (BMDC) demonstrated that PSK induces DC maturation as shown by dose-dependent increase in the expression of CD80, CD86, MHCII, and CD40. PSK also induces the production of multiple inflammatory cytokines by DC, including IL-12, TNF-?, and IL-6, at both mRNA and protein levels. In vivo experiments using PSK as an adjuvant to OVAp323-339 vaccine showed that PSK as adjuvant leads to enlarged draining lymph nodes with higher number of activated DC. PSK also stimulates proliferation of OVA-specific T cells, and induces T cells that produce multiple cytokines, IFN-?, IL-2, and TNF-?. Altogether, these results demonstrate the ability of PSK to activate DC in vitro and in vivo and the potential of using PSK as a novel vaccine adjuvant.

SUBMITTER: Engel AL 

PROVIDER: S-EPMC3783519 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature