Abstract:
Mycobacterium bovis (M. bovis) infection in wildlife, including lions (Panthera leo), has
implications for individual and population health. Tools for the detection of infected lions are needed
for diagnosis and disease surveillance. This study aimed to evaluate the Mabtech Cat interferon
gamma (IFN-
) ELISABasic kit for detection of native lion IFN-
in whole blood samples stimulated
using the QuantiFERON® TB Gold Plus (QFT) platform as a potential diagnostic assay. The ELISA
was able to detect lion IFN-
in mitogen-stimulated samples, with good parallelism, linearity, and
a working range of 15.6–500 pg/mL. Minimal matrix interference was observed in the recovery of
domestic cat rIFN-
in lion plasma. Both intra- and inter-assay reproducibility had a coefficient
of variation less than 10%, while the limit of detection and quantification were 7.8 pg/mL and
31.2 pg/mL, respectively. The diagnostic performance of the QFT Mabtech Cat interferon gamma
release assay (IGRA) was determined using mycobacterial antigen-stimulated samples from M. bovis
culture-confirmed infected (n = 8) and uninfected (n = 4) lions. A lion-specific cut-off value (33 pg/mL)
was calculated, and the sensitivity and specificity were determined to be 87.5% and 100%, respectively.
Although additional samples should be tested, the QFT Mabtech Cat IGRA could identify M. bovisinfected
African lions.