Shao Mingzhu, Cui Ning, Tang Yangyang, Chen Fanruo, Cui Yingying, Dang Guanghui, Liu Siguo
State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Street, Harbin, 150069, PR China.
NPJ Vaccines. 2023 May 20;8(1):72. doi: 10.1038/s41541-023-00675-1.
Mycobacterium avium subspecies paratuberculosis (MAP) causes paratuberculosis (PTB), which is a granulomatous enteritis in ruminants that threatens the dairy industry's healthy development and public health safety worldwide. Because the commercial inactivated vaccines are not completely protective and interfere with bovine tuberculosis diagnostics, we tested four fusion proteins, namely 66NC, 66CN, 90NC, and 90CN, which were constructed with MAP3527, Ag85B, and Hsp70 of MAP in different tandem combinations. Notably, 66NC, which encodes a 66 kDa fusion protein that combines in linear order MAP3527, Ag85B, and MAP3527 induced a powerful and specific IFN-γ response. Immunization of C57BL/6 mice with the 66NC fusion protein formulated in Montanide ISA 61 VG adjuvant generated robust Th1, Th2, and Th17 type immune responses and strong antibody responses. The 66NC vaccine protected C57BL/6 mice against virulent MAP K-10 infection. This resulted in a reduction of bacterial load and improvement of pathological damage in the liver and intestine, in addition to a reduction of body weight loss; significantly better protection than the reported 74 F vaccine was also induced. Furthermore, vaccine efficacy correlated with the levels of IFN-γ-, TNF-α-, and IL-17A-secreting antigen-specific CD4 and CD8 T lymphocytes as well as with serum IFN-γ and TNF-α levels after vaccination. These results demonstrate that recombinant protein 66NC is an efficient candidate for further development into a protective vaccine in terms of inducing specific protection against MAP.
鸟分枝杆菌副结核亚种（MAP）可引发副结核病（PTB），这是一种反刍动物的肉芽肿性肠炎，对全球乳制品行业的健康发展和公共卫生安全构成威胁。由于商业化灭活疫苗并非完全具有保护性，且会干扰牛结核病的诊断，我们测试了四种融合蛋白，即66NC、66CN、90NC和90CN，它们是由MAP的MAP3527、Ag85B和Hsp70以不同的串联组合构建而成。值得注意的是，66NC编码一种66 kDa的融合蛋白，该蛋白按线性顺序结合了MAP3527、Ag85B和MAP3527，可诱导强烈且特异性的IFN-γ反应。用在Montanide ISA 61 VG佐剂中配制的66NC融合蛋白免疫C57BL/6小鼠，可产生强大的Th1、Th2和Th17型免疫反应以及强烈的抗体反应。66NC疫苗可保护C57BL/6小鼠免受强毒力MAP K-10感染。这导致细菌载量降低，肝脏和肠道的病理损伤得到改善，同时体重减轻也有所减少；诱导的保护效果明显优于已报道的74F疫苗。此外，疫苗效力与接种后分泌IFN-γ、TNF-α和IL-17A的抗原特异性CD4和CD8 T淋巴细胞水平以及血清IFN-γ和TNF-α水平相关。这些结果表明，就诱导针对MAP的特异性保护而言，重组蛋白66NC是进一步开发成保护性疫苗的有效候选物。
