Recognition of recombinant interferon-gamma from Felidae species by anti-cat antibodies

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 (IFN gamma) 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 IFN gamma antibodies can bind to recombinant IFN gamma (rIFN gamma) from other Felidae species, permitting use of the feline IGRA in a wider range of felids. Unique Felidae IFN gamma protein sequences and their corresponding coding nucleotide sequence were identified from online databases; plasmids with an IFN gamma-gene insert were synthesised to transform E. coli-DH5 alpha and subsequently transfect HEK 293 T cells to secrete rIFN gamma. Enzyme-linked immunosorbent assay using a commercial anti-cat IFN gamma kit was performed to detect rIFN gamma from Felidae, the domestic dog and cattle. Five unique rIFN gamma Felidae proteins were synthesised; anticat IFN gamma antibodies were able to bind to all five proteins, while cross-reactivity with canine and bovine rIFN gamma was negligible. This suggests that anti-cat IFN gamma antibodies are sufficient for detection of IFN gamma across other Felidae species, namely the lion, tiger, cheetah, cougar, Iberian lynx and the Canadian lynx.

Automated summary

Research has shown that anti-cat IFN gamma antibodies can effectively detect IFN gamma in other Felidae species such as lions, tigers, and cheetahs, aiding in the protection of animals threatened by mycobacterial infections.