Mycobacterium bovis (M. bovis), the cause of bovine tuberculosis, is endemic in Kruger National Park (KNP), South Africa. The risk of spread of M. bovis infection currently prevents translocation of white rhinoceros (Ceratotherium simum) from this population. Therefore, accurate assays are necessary for screening this threatened species. Interferon gamma (IFN-γ) release assays (IGRA) are commonly used for tuberculosis diagnosis in humans and other wildlife species. Hence, the aim of this study was to develop an IGRA for M. bovis detection in white rhinoceros. Heparinized whole blood was collected from immobilized white rhinoceros in KNP (n = 131) and incubated overnight in QuantiFERON®-TB Gold (QFT) blood collection tubes, after which the plasma was harvested following centrifugation. Tissue samples for mycobacterial culture were available from a subset of 21 rhinoceros. The concentration of IFN-γ in plasma samples was measured using the Mabtech equine IFN-γ ELISAPRO kit. An IGRA result was calculated as the difference in IFN-γ concentrations in the QFT Nil and TB antigen tubes. Using test results for the white rhinoceros with known infection status, a diagnostic cut-off value was calculated as 21 pg/ml. Additionally, cut-off values for IFN-γ concentrations for plasma from QFT Nil and QFT Mitogen tubes were calculated to increase confidence in IGRA result interpretation. The combination of the QFT stimulation platform and Mabtech equine IFN-γ ELISA is a promising diagnostic test to distinguish between of M. bovis-infected and -uninfected white rhinoceros.

中文翻译：

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干扰素-γ释放测定法可用于诊断白犀牛（Ceratotherium simum）中的牛分枝杆菌感染。

牛结核分枝杆菌（牛分枝杆菌）是牛结核病的病因，在南非克鲁格国家公园（KNP）流行。牛分枝杆菌感染的传播风险目前阻止了该种群白犀牛（白鼬）的易位。因此，准确的检测方法对于筛选这种受威胁物种是必要的。干扰素γ（IFN-γ）释放测定（IGRA）通常用于人类和其他野生动植物物种的结核病诊断。因此，本研究的目的是开发一种用于白犀牛中牛分枝杆菌检测的IGRA。从固定在KNP中的白犀牛（n = 131）收集肝素化的全血，并在QuantiFERON®-TBGold（QFT）采血管中孵育过夜，然后离心收集血浆。分枝杆菌培养的组织样品可从21个犀牛的子集中获得。使用Mabtech马IFN-γELISAPRO试剂盒测量血浆样品中IFN-γ的浓度。将IGRA结果计算为QFT Nil和TB抗原试管中IFN-γ浓度的差异。使用已知感染状态的白犀牛的测试结果，计算得出的诊断临界值为21 pg / ml。此外，计算了来自QFT Nil和QFT Mitogen管的血浆中IFN-γ浓度的临界值，以增加对IGRA结果解释的信心。QFT刺激平台和Mabtech马IFN-γELISA的组合是一种有前途的诊断测试，可以区分牛分枝杆菌感染和未感染的白犀牛。使用Mabtech马IFN-γELISAPRO试剂盒测量血浆样品中IFN-γ的浓度。将IGRA结果计算为QFT Nil和TB抗原试管中IFN-γ浓度的差异。使用已知感染状况的白犀牛的测试结果，计算出的诊断临界值为21 pg / ml。此外，计算了来自QFT Nil和QFT Mitogen管的血浆中IFN-γ浓度的临界值，以增加对IGRA结果解释的信心。QFT刺激平台和Mabtech马IFN-γELISA的组合是一种有前途的诊断测试，可以区分牛分枝杆菌感染和未感染的白犀牛。使用Mabtech马IFN-γELISAPRO试剂盒测量血浆样品中IFN-γ的浓度。将IGRA结果计算为QFT Nil和TB抗原试管中IFN-γ浓度的差异。使用已知感染状态的白犀牛的测试结果，计算得出的诊断临界值为21 pg / ml。此外，计算了来自QFT Nil和QFT Mitogen管的血浆中IFN-γ浓度的临界值，以增加对IGRA结果解释的信心。QFT刺激平台和Mabtech马IFN-γELISA的组合是一种有前途的诊断测试，可以区分牛分枝杆菌感染和未感染的白犀牛。使用已知感染状态的白犀牛的测试结果，计算得出的诊断临界值为21 pg / ml。此外，计算了来自QFT Nil和QFT Mitogen管的血浆中IFN-γ浓度的临界值，以增加对IGRA结果解释的信心。QFT刺激平台和Mabtech马IFN-γELISA的组合是一种有前途的诊断测试，可以区分牛分枝杆菌感染和未感染的白犀牛。使用已知感染状态的白犀牛的测试结果，计算得出的诊断临界值为21 pg / ml。此外，计算了来自QFT Nil和QFT Mitogen管的血浆中IFN-γ浓度的临界值，以增加对IGRA结果解释的信心。QFT刺激平台和Mabtech马IFN-γELISA的组合是一种有前途的诊断测试，可以区分牛分枝杆菌感染和未感染的白犀牛。