Pickering emulsion stabilized by Chinese Yam polysaccharides PLGA for enhanced humoral and cellular immune responses.

As an important ingredient of Chinese yam, Chinese yam polysaccharides have received wide attention for their remarkable adjuvant activity. Pickering emulsion is an attractive platform for the delivery of vaccines. Our previous study has demonstrated that the Chinese yam polysaccharides PLGA-stabilized Pickering emulsion (CYP-PPAS) is a potentially safe and efficient adjuvant to improve the immune response. In this work, we further investigate the adjuvant activity of CYP-PPAS on cellular immunity. In vitro, the CYP-PPAS increased antigen uptake efficiency by DCs. In vivo, CYP-PPAS triggered the recruitment of DCs and macrophages and subsequently facilitated DCs maturation and antigen migration to lymph nodes. Furthermore, CYP-PPAS induced a robust humoral response and Th1/Th2 immune response, enhanced the activation of CD4 and CD8 T lymphocyte subpopulations, and also promoted the activation of cytotoxic T lymphocyte response. As a result, the CYP-PPAS serves as a promising vaccine delivery system to induce robust humoral and cellular immunities against diseases.