In the present study, we evaluated adjuvant potential of Poria cocos polysaccharide (PCP) on the Th1-type immune responses of C57/BL6 mice against ovalbumin (OVA). We first determined the effect of PCP on maturation of murine bone marrow derived dendritic cells (BMDCs), PCP significantly upregulated surface expression of MHCII, CD40, CD80, CD86 and enhanced production of IL-6 and IL-12p40. In addition, PCP affected receptor-mediated endocytosis, but not pinocytosis in BMDCs. Furthermore, OVA + PCP immunization induced specific cytotoxic CD8⁺ T cell killing of OVA (257–264) peptide pulsed cell. When mice were immunized subcutaneously in a week interval with OVA + PCP. Serum were collected for measuring OVA-specific antibody and splenocytes were harvested for analyzing CD69, IFN-γ ELISpot and cytokines production. The result indicated that OVA-specific IgG, IgG2a and IgG1 antibody levels in serum were significantly elevated by PCP compared with control. PCP increased OVA-specific IFN-γ-secreting CD8⁺, CD4⁺ T cells, promoted CD8⁺ T cell proliferation and up-regulated Th-1 type (IFN-γ, IL-2) cytokine production. In conclusion, data suggest that PCP enhanced cellular immune response and possess potential as a vaccine adjuvant for Th1 immune response.

在本研究中，我们评估了Por多糖（PCP）对C57 / BL6小鼠针对卵清蛋白（OVA）的Th1型免疫应答的佐剂潜力。我们首先确定了PCP对鼠骨髓源性树突状细胞（BMDC）成熟的影响，PCP显着上调了MHCII，CD40，CD80，CD86的表面表达，并增强了IL-6和IL-12p40的产生。此外，五氯苯酚可影响BMDCs受体介导的内吞作用，但不影响胞饮作用。此外，OVA + PCP免疫诱导特异性细胞毒性CD8 ⁺T细胞杀灭OVA（257–264）肽脉冲细胞。当用OVA + PCP在一周的间隔内对小鼠进行皮下免疫时。收集血清以测量OVA特异性抗体，并收集脾细胞用于分析CD69，IFN-γELISpot和细胞因子产生。结果表明，与对照组相比，PCP显着提高了血清中OVA特异性IgG，IgG2a和IgG1抗体的水平。PCP可增加OVA特异性分泌IFN-γ的CD8 ⁺，CD4 ⁺ T细胞，促进CD8 ⁺ T细胞增殖并上调Th-1型（IFN-γ，IL-2）细胞因子的产生。总之，数据表明PCP增强了细胞免疫应答，并具有作为Th1免疫应答的疫苗佐剂的潜力。