Department of Molecular Genetics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
Department of Microbiology, Immunology, and Infectious Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
Front Immunol. 2024 May 21;15:1392681. doi: 10.3389/fimmu.2024.1392681. eCollection 2024.
is a bacterial pathogen that causes a variety of infections across diverse animal species, with one of the most devastating associated diseases being hemorrhagic septicemia. Outbreaks of hemorrhagic septicemia in cattle and buffaloes are marked by rapid progression and high mortality. These infections have particularly harmful socio-economic impacts on small holder farmers in Africa and Asia who are heavily reliant on a small number of animals kept as a means of subsistence for milk and draft power purposes. A novel vaccine target, PmSLP-3, has been identified on the surface of hemorrhagic septicemia-associated strains of and was previously shown to elicit robust protection in cattle against lethal challenge with a serogroup B strain.
Here, we further investigate the protective efficacy of this surface lipoprotein, including evaluating the immunogenicity and protection upon formulation with a variety of adjuvants in both mice and cattle.
PmSLP-3 formulated with Montanide ISA 61 elicited the highest level of serum and mucosal IgG, elicited long-lasting serum antibodies, and was fully protective against serogroup B challenge. Studies were then performed to identify the minimum number of doses required and the needed protein quantity to maintain protection. Duration studies were performed in cattle, demonstrating sustained serum IgG titres for 3 years after two doses of vaccine and full protection against lethal serogroup B challenge at 7 months after a single vaccine dose. Finally, a serogroup E challenge study was performed, demonstrating that PmSLP-3 vaccine can provide protection against challenge by the two serogroups responsible for hemorrhagic septicemia.
Together, these data indicate that PmSLP-3 formulated with Montanide ISA 61 is an immunogenic and protective vaccine against hemorrhagic septicemia-causing strains in cattle.
是一种细菌病原体，可导致多种动物物种的感染，其中最具破坏性的相关疾病是出血性败血症。牛和水牛出血性败血症的爆发以快速发展和高死亡率为特征。这些感染对非洲和亚洲的小农户造成了特别有害的社会经济影响，他们严重依赖少数动物作为生存手段，用于提供牛奶和役力。一种新型疫苗靶标 PmSLP-3 已在与出血性败血症相关的菌株的表面上被鉴定出来，并且先前已经证明它可以在牛中引起针对血清群 B 菌株的致死性挑战的强大保护。
在这里，我们进一步研究了这种表面脂蛋白的保护效力，包括评估其在与各种佐剂联合使用时在小鼠和牛中的免疫原性和保护作用。
与 Montanide ISA 61 联合配制的 PmSLP-3 引起了最高水平的血清和粘膜 IgG，引起了持久的血清抗体，并完全保护免受血清群 B 挑战。然后进行了研究以确定维持保护所需的最小剂量数和所需的蛋白质量。在牛中进行了持续时间研究，表明在两次疫苗接种后，血清 IgG 滴度可持续 3 年，并且在单次疫苗接种后 7 个月可完全保护免受致命的血清群 B 挑战。最后，进行了血清群 E 挑战研究，表明 PmSLP-3 疫苗可以提供针对引起出血性败血症的两种血清群的挑战的保护。
总之，这些数据表明，与 Montanide ISA 61 联合配制的 PmSLP-3 是一种针对牛中引起出血性败血症的菌株的免疫原性和保护性疫苗。
