Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis) infection, disrupts conservation programs of threatened species such as the white rhinoceros (Ceratotherium simum). Interferon gamma release assays have been developed for the diagnosis of M. bovis infection in rhinoceros, however, the discovery of additional diagnostic biomarkers might improve the accuracy of case detection. The aim of this pilot study was therefore to evaluate a novel unbiased approach to candidate biomarker discovery and preliminary validation. Whole blood samples from twelve white rhinoceros were incubated in Nil and TB antigen tubes of the QuantiFERON® TB Gold (In-Tube) system after which RNA was extracted and reverse transcribed. Using the equine RT² profiler PCR array, relative gene expression analysis of samples from two immune sensitized rhinoceros identified CCL4, CCL8, IL23A, LTA, NODAL, TNF, CSF3, CXCL10 and GPI as upregulated in response to antigen stimulation. Novel gene expression assays (GEAs) were designed for selected candidates, i.e. CCL4, CXCL10 and IFNG, and analysis of QFT-processed samples showed the CXCL10 GEA could distinguish between five M. bovis-infected and five uninfected rhinoceros. These findings confirm the value of the equine RT² profiler PCR array as a useful tool for screening biomarkers for the diagnosis of M. bovis infection in rhinoceros.

由牛分枝杆菌（M. bovis）感染引起的牛结核病（bTB）破坏了诸如白犀牛（Ceratotherium simum）等濒危物种的保护程序。已经开发了干扰素γ释放试验来诊断牛分枝杆菌然而，在犀牛感染中，发现其他诊断性生物标志物可能会提高病例检测的准确性。因此，该初步研究的目的是评估一种新颖的，偏向候选生物标志物发现和初步验证的方法。将来自十二只白犀牛的全血样品在QuantiFERON®TB Gold（管内）系统的Nil和TB抗原试管中孵育，然后提取RNA并进行反转录。使用马RT ² Profiler PCR阵列，对来自两个免疫致敏犀牛的样品的相对基因表达分析，确定了CCL4，CCL8，IL23A，LTA，NODAL，TNF，CSF3，CXCL10和GPI响应抗原刺激而被上调。针对选定的候选基因（即CCL4，CXCL10和IFNG）设计了新的基因表达测定法（GEA），对QFT处理过的样品进行分析后发现，CXCL10 GEA可以区分5例感染牛分枝杆菌和5例未感染的犀牛。这些发现证实了马RT ² Profiler PCR阵列作为筛选生物标志物以诊断犀牛中牛分枝杆菌感染的有用工具的价值。