College of Life Science and Technology, Bayi Agricultural University, Daqing, Heilongjiang, China.
College of Animal Science and Veterinary Medicine, Bayi Agricultural University, Daqing, Heilongjiang, China.
Immun Inflamm Dis. 2021 Sep;9(3):971-983. doi: 10.1002/iid3.456. Epub 2021 May 19.
Staphylococcus aureus (S. aureus) is a gram-positive opportunistic pathogen, there are currently no high effective vaccine against S. aureus in humans and animals, the development of an efficient vaccine remains an important challenge to prevent S. aureus infection. Here, we prepared Als3-Th-cell-epitope-Target of RNAIII Activating Protein (TRAP) (ATT) proteins plus the novel combined adjuvants to develop a promising vaccine candidate against S. aureus.
The recombinant pET-28a (+)-att plasmids were constructed, and the ATT proteins were expressed and obtained, then, ATT plus Freund's adjuvant or the novel combined adjuvants of cytosine-phosphate-guanosine oligodeoxynucleotides (CpG), muramyl dipeptides (MDP), and FIA were immunized in mice. After booster immunization, the levels of interferon-γ (IFN-γ), interleukin-4 (IL-4), IL-10 and IL-17A cytokine were evaluated, the humoral immune responses against TRAP were detected in mice, and the survival rate of mice was confirmed by challenge assay.
The mice immunized with ATT plus Freund's adjuvant exhibited significantly higher level of IFN-γ, IL-4, IL-10, and IL-17A, and displayed the stronger humoral immune response against TRAP than control groups, importantly, the survival rate of these mice was significantly higher than control groups. In addition, compared with the control groups, ATT + CpG + MDP + FIA group was elicited significantly higher level of IFN-γ, IL-4, IL-10, and IL-17A and was triggered the stronger humoral immune responses against TRAP, moreover, generated the higher survival rate of mice.
Als3 epitopes significantly enhanced TRAP immunogenicity. ATT plus the novel combined adjuvants of CpG, MDP, and FIA induced the strong immune response and protection against S. aureus, revealing the combination of CpG, MDP, and FIA adjuvant acts the synergistic effect.
金黄色葡萄球菌（S. aureus）是一种革兰氏阳性机会致病菌，目前人类和动物中尚无针对金黄色葡萄球菌的高效疫苗，因此开发有效的疫苗仍然是预防金黄色葡萄球菌感染的重要挑战。在这里，我们制备了 Als3-Th 细胞表位-TRAP（ATT）蛋白加新型联合佐剂，以开发针对金黄色葡萄球菌的有前途的疫苗候选物。
构建了重组 pET-28a（+）-att 质粒，表达并获得了 ATT 蛋白，然后用 ATT 加弗氏佐剂或新型联合佐剂胞嘧啶-磷酸-鸟嘌呤寡脱氧核苷酸（CpG）、双肽基二肽（MDP）和 FIA 对小鼠进行免疫。加强免疫后，评估干扰素-γ（IFN-γ）、白细胞介素-4（IL-4）、白细胞介素-10（IL-10）和白细胞介素-17A 细胞因子水平，检测小鼠对 TRAP 的体液免疫反应，并通过攻毒试验确认小鼠的存活率。
用 ATT 加弗氏佐剂免疫的小鼠 IFN-γ、IL-4、IL-10 和 IL-17A 水平显著升高，对 TRAP 的体液免疫反应也比对照组强，重要的是，这些小鼠的存活率明显高于对照组。此外，与对照组相比，ATT+CpG+MDP+FIA 组诱导 IFN-γ、IL-4、IL-10 和 IL-17A 水平显著升高，对 TRAP 的体液免疫反应更强，而且产生了更高的小鼠存活率。
Als3 表位显著增强了 TRAP 的免疫原性。ATT 加新型 CpG、MDP 和 FIA 联合佐剂诱导了针对金黄色葡萄球菌的强烈免疫反应和保护作用，表明 CpG、MDP 和 FIA 佐剂联合具有协同作用。
