Rehmannia glutinosa polysaccharide liposome as a novel strategy for stimulating an efficient immune response and their effects on dendritic cells

Abstract

Nanomedicine, the medical application of nanotechnology, promises a seemingly limitless range of applications from drug delivery to adjuvants and therapeutics. Our current research is focused on natural polymer-based liposome adjuvants. With the aim of inducing protective and long-lasting immunity, the immunological adjuvant activity of Rehmannia glutinosa polysaccharide liposome (RGPL) was investigated. In vivo, the splenic lymphocyte proliferation ratios and ovalbumin-specific immunoglobulin G titers of ovalbumin-RGPL-vaccinated mice were significantly upregulated. In draining lymph nodes, the expression of MHC II⁺CD11c⁺ and CD86⁺CD11c⁺ was increased by RGPL; in addition, the percentages of central memory cells (T_CM) and effector memory cells (T_EM) were also elevated. RGPL could effectively provide adequate antigen exposure in lymph nodes. In vitro, RGPL could promote dendritic cell maturation and enhance dendritic cell functions, such as the mixed lymphocyte reaction and antigen presentation. Overall, the results demonstrated that RGPL has the potential to act as an effective controlled release vaccine adjuvant.

Keywords:

• Rehmannia glutinosa polysaccharide liposome
• adjuvant
• controlled release
• ovalbumin
• dendritic cells

Acknowledgments

The project was supported by the National Natural Science Foundation of China (grant nos 31372472, 31201880), the Special Fund for Agro-scientific Research in the Public Interest (grant nos 201303046, 201403051), and by the Priority Academic Program Development of Jiangsu Higher Education Institutions. We are grateful to all the other staff at the Institute of Traditional Chinese Veterinary Medicine of Nanjing Agricultural University for their assistance with the experiments.

Author contributions

Yee Huang and DW conceived the idea and designed the Rehmannia glutinosa polysaccharide liposome (RGPL). Yee Huang synthesized and characterized the RGPL. Yee Huang, TQ, Yifan Huang, ZL, and RB designed studies on cells and animals. Yee Huang, TQ, Yifan Huang, ZL, and RB performed the experiments on cells and animals. Yee Huang wrote the paper and all the authors commented on the manuscript. Yee Huang and DW supervised all the studies described in this report. All authors contributed toward data analysis, drafting and revising the paper and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.