Abstract:
Capripoxviruses are the causative agents of sheeppox, goatpox, and lumpy skin disease (LSD) in cattle, which cause economic losses to the livestock industry in Africa and Asia. Capripoxviruses are currently controlled using several live attenuated vaccines. It was previously demonstrated that a lumpy skin disease virus (LSDV) field isolate from Warmbaths (WB) South Africa, ORF 005 (IL-10) gene-deleted virus (LSDV WB005KO), was able to protect sheep and goats against sheeppox and goatpox. Subsequently, genes encoding the protective antigens for peste des petits ruminants (PPR) and Rift Valley fever (RVF) viruses have been inserted in the LSDV WB005KO construct in three different antigen forms (native, secreted, and fusion). These three multivalent vaccine candidates were evaluated for protection against PPR using a single immunization of 104 TCID50 in sheep. The vaccine candidates with the native and secreted antigens protected sheep against PPR clinical disease and decreased viral shedding, as detected using real-time RT-PCR in oral and nasal swabs. An anamnestic antibody response, measured using PPR virus-neutralizing antibody response production, was observed in sheep following infection. The vaccine candidates with the antigens expressed in their native form were evaluated for protection against RVF using a single immunization with doses of 104 or 105 TCID50 in sheep and goats. Following RVF virus infection, sheep and goats were protected against clinical disease and no viremia was detected in serum compared to control animals, where viremia was detected one day following infection. Sheep and goats developed RVFV-neutralizing antibodies prior to infection, and the antibody responses increased following infection. These results demonstrate that an LSD virus-vectored vaccine candidate can be used in sheep and goats to protect against multiple viral infections.
摘要:
羊痘病毒是羊痘的病原体,山羊痘,牛的块状皮肤病(LSD),这给非洲和亚洲的畜牧业造成了经济损失。目前使用几种减毒活疫苗来控制角痘病毒。先前已证明,从南非Warmbaths(WB)分离出块状皮肤病病毒(LSDV),ORF005(IL-10)基因缺失病毒(LSDVWB005KO),能够保护绵羊和山羊免受羊痘和山痘的侵害。随后,编码小反刍动物(PPR)和裂谷热(RVF)病毒保护性抗原的基因已以三种不同的抗原形式插入LSDVWB005KO构建体中(天然,分泌的,和融合)。在绵羊中使用104TCID50的单次免疫来评估这三种多价疫苗候选物对PPR的保护作用。具有天然和分泌抗原的候选疫苗可保护绵羊免受PPR临床疾病的侵害,并减少病毒的脱落。如使用实时RT-PCR在口腔和鼻拭子中检测到的。遗忘抗体反应,使用PPR病毒中和抗体反应产生进行测量,在感染后的绵羊中观察到。使用104或105TCID50剂量的单次免疫在绵羊和山羊中评估具有以其天然形式表达的抗原的疫苗候选物对RVF的保护作用。RVF病毒感染后,与对照动物相比,绵羊和山羊被保护免受临床疾病的侵害,血清中没有检测到病毒血症,感染后一天检测到病毒血症。绵羊和山羊在感染前产生了RVFV中和抗体,感染后抗体反应增加。这些结果表明,LSD病毒载体化的候选疫苗可用于绵羊和山羊以防止多种病毒感染。