Mycobacterial infections cause a reasonable burden of morbidity and mortality in global feline populations, many of which are ‘Vulnerable’ or ‘Endangered’. Identifying these infections may facilitate efforts to protect these animals. An interferon-gamma (IFNγ) release assay (IGRA) to diagnose mycobacteriosis in domestic cats has been adapted for use in lions; however, the development of species-specific antibodies may be laborious. Therefore, we investigated whether anti-cat IFNγ antibodies can bind to recombinant IFNγ (rIFNγ) from other Felidae species, permitting use of the feline IGRA in a wider range of felids. Unique Felidae IFNγ protein sequences and their corresponding coding nucleotide sequence were identified from online databases; plasmids with an IFNγ-gene insert were synthesised to transform E. coli-DH5α and subsequently transfect HEK 293 T cells to secrete rIFNγ. Enzyme-linked immunosorbent assay using a commercial anti-cat IFNγ kit was performed to detect rIFNγ from Felidae, the domestic dog and cattle. Five unique rIFNγ Felidae proteins were synthesised; anti-cat IFNγ antibodies were able to bind to all five proteins, while cross-reactivity with canine and bovine rIFNγ was negligible. This suggests that anti-cat IFNγ antibodies are sufficient for detection of IFNγ across other Felidae species, namely the lion, tiger, cheetah, cougar, Iberian lynx and the Canadian lynx.

分枝杆菌感染在全球猫科动物种群中造成了合理的发病率和死亡率负担，其中许多是“易危”或“濒危”。识别这些感染可能有助于保护这些动物的努力。用于诊断家猫分枝杆菌病的干扰素-γ (IFNγ) 释放试验 (IGRA) 已适用于狮子；然而，物种特异性抗体的开发可能很费力。因此，我们研究了抗猫 IFNγ 抗体是否可以与来自其他猫科物种的重组 IFNγ (rIFNγ) 结合，从而允许在更广泛的猫科动物中使用猫 IGRA。从在线数据库中鉴定出独特的猫科 IFNγ 蛋白序列及其相应的编码核苷酸序列；合成具有 IFNγ 基因插入物的质粒以转化大肠杆菌-DH5α 并随后转染 HEK 293 T 细胞以分泌 rIFNγ。使用商业抗猫 IFNγ 试剂盒进行酶联免疫吸附测定以检测来自猫科、家犬和牛的 rIFNγ。合成了五种独特的 rIFNγ 猫科蛋白质；抗猫 IFNγ 抗体能够与所有五种蛋白质结合，而与犬和牛 rIFNγ 的交叉反应可以忽略不计。这表明抗猫 IFNγ 抗体足以检测其他猫科动物的 IFNγ，即狮子、老虎、猎豹、美洲狮、伊比利亚猞猁和加拿大猞猁。