Zhang Jing, Feng Jing, Huang Yang, Zhou Boyan, Li Bing, Zhang Rongxin
Laboratory of Immunology and Inflammation, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou 510006, China.
Vaccines (Basel). 2023 Dec 8;11(12):1833. doi: 10.3390/vaccines11121833.
The COVID-19 pandemic remarkably accelerated vaccine research progress. The role of adjuvants in enhancing vaccine immune intensity and influencing immune types has been considered. Ginseng polysaccharide (GPS) has been demonstrated to have strong immunoregulatory properties. It is important to explore the feasibility of adding GPS to vaccine adjuvant components to improve the immune response effect of RBD vaccines. Here, we prepared a SARS-CoV-2 RBD antigen using the expression system and determined that subcutaneous administration of GPS at a dose of 40 mg/kg could effectively activate dendritic cells (DCs) and macrophages (MΦ) in mice. Compared with the RBD group, the RBD+GPS triggered stronger and persistent antibody responses. It is also notable that higher levels of RBD-specific IgG and IgA were distributed in the lungs of RBD+GPS-immunized BALB/c mice. In addition, the RBD+GPS also resulted in lower percentages of IFN-γ CD4 T cells and higher percentages of IFN-γ CD8 T cells and CD8 Tcm cells. These results suggest that GPS could be a promising vaccine immuno-enhancer for SARS-CoV-2 RBD subunit vaccines to establish stronger systemic and pulmonary mucosal protective immunity.
新冠疫情显著加速了疫苗研究进程。人们已开始考虑佐剂在增强疫苗免疫强度及影响免疫类型方面的作用。人参多糖（GPS）已被证明具有强大的免疫调节特性。探究将GPS添加到疫苗佐剂成分中以提高RBD疫苗免疫应答效果的可行性具有重要意义。在此，我们使用表达系统制备了新冠病毒RBD抗原，并确定以40mg/kg的剂量皮下注射GPS可有效激活小鼠体内的树突状细胞（DCs）和巨噬细胞（MΦ）。与RBD组相比，RBD+GPS引发了更强且持久的抗体反应。同样值得注意的是，在RBD+GPS免疫的BALB/c小鼠肺部，RBD特异性IgG和IgA水平更高。此外，RBD+GPS还导致IFN-γ CD4 T细胞百分比降低，IFN-γ CD8 T细胞和CD8 Tcm细胞百分比升高。这些结果表明，GPS有望成为一种用于新冠病毒RBD亚单位疫苗的免疫增强剂，以建立更强的全身和肺部黏膜保护性免疫。
