Nandini Prachita, Jakka Padmaja, Murugan Subathra, Mazumdar Varadendra, Kumar Deepak, Prakash Richa, Barbuddhe Sukhadeo B, Radhakrishnan Girish
National Institute of Animal Biotechnology (NIAB), Hyderabad, India.
Regional Centre for Biotechnology (RCB), Faridabad, India.
Front Microbiol. 2023 Oct 4;14:1253349. doi: 10.3389/fmicb.2023.1253349. eCollection 2023.
Brucellosis remains a worldwide zoonotic disease with a serious impact on public health and livestock productivity. Controlling brucellosis in livestock is crucial for limiting human infections in the absence of effective human vaccines. Brucellosis control measures are majorly dependent on rigorous monitoring of disease outbreaks and mass vaccination of livestock. Live attenuated vaccines are available for livestock vaccination that play a vital role in brucellosis control programs in many countries. Even though the existing animal vaccines confer protection against brucellosis, they carry some drawbacks, including their infectivity to humans and interference with sero-monitoring. The available serodiagnostic assays for brucellosis depend on detecting anti-LPS antibodies in the serum. Since diagnosis plays a vital role in controlling brucellosis, developing improved serodiagnostic assays with enhanced specificity, sensitivity and DIVA capability is required. Therefore, it is essential to identify novel antigens for developing improved vaccines and serodiagnostic assays for brucellosis. In the present study, we performed a high throughput immunoprofiling of protein microarray using brucellosis-positive human and animal serum samples. The screening identified several serodominant proteins of that exhibited common or differential reactivity with sera from animals and humans. Subsequently, we cloned, expressed, and purified ten serodominant proteins, followed by analyzing their potential to develop next-generation vaccines and improved serodiagnostic assays for brucellosis. Further, we demonstrated the protective efficacy of one of the serodominant proteins against the challenge in mice. We found that the seroreactive protein, Dps (BMEI1980), strongly reacted with brucellosis-positive serum samples, but it did not react with sera from S19-vaccinated cattle, indicating DIVA capability. A prototype lateral flow assay and indirect ELISA based on Dps protein exhibited high sensitivity, specificity, and DIVA capability. Thus, the present study identified promising candidates for developing improved vaccines and affordable, DIVA-capable serodiagnostic assays for animal and human brucellosis.
布鲁氏菌病仍然是一种全球性人畜共患病，对公众健康和家畜生产力有严重影响。在缺乏有效的人类疫苗的情况下，控制家畜中的布鲁氏菌病对于限制人类感染至关重要。布鲁氏菌病控制措施主要依赖于对疾病暴发的严格监测和家畜的大规模疫苗接种。有减毒活疫苗可用于家畜接种，在许多国家的布鲁氏菌病控制计划中发挥着至关重要的作用。尽管现有的动物疫苗可提供针对布鲁氏菌病的保护，但它们存在一些缺点，包括对人类的感染性以及对血清监测的干扰。现有的布鲁氏菌病血清学诊断检测依赖于检测血清中的抗脂多糖抗体。由于诊断在控制布鲁氏菌病中起着至关重要的作用，因此需要开发具有更高特异性、敏感性和鉴别诊断能力的改进型血清学诊断检测方法。因此，识别新型抗原以开发改进的布鲁氏菌病疫苗和血清学诊断检测方法至关重要。在本研究中，我们使用布鲁氏菌病阳性的人类和动物血清样本对蛋白质微阵列进行了高通量免疫分析。筛选确定了几种血清显性蛋白，它们与动物和人类血清表现出共同或不同的反应性。随后，我们克隆、表达并纯化了十种血清显性蛋白，然后分析它们开发下一代疫苗和改进的布鲁氏菌病血清学诊断检测方法的潜力。此外，我们证明了其中一种血清显性蛋白对小鼠感染攻击的保护效力。我们发现血清反应性蛋白Dps（BMEI1980）与布鲁氏菌病阳性血清样本强烈反应，但与S19疫苗接种牛的血清不反应，表明具有鉴别诊断能力。基于Dps蛋白的原型侧向流检测和间接ELISA表现出高灵敏度、特异性和鉴别诊断能力。因此，本研究确定了有前景的候选物，可用于开发改进的疫苗以及用于动物和人类布鲁氏菌病的具有鉴别诊断能力且价格合理的血清学诊断检测方法。
