Efficacy of using gama interferon assay for evaluation of vaccination with sheep pox vaccine against lumpy skin disease in cattle

الملخص EN

Critical considerations for optimizing and conducting assays for large population based studies are feasibility, amount of sample aliquots, processing time and cost.

Well-designed statistical approaches that quickly identify optimal conditions for a given assay could assist efficient completion of the laboratory assays, in the present study, the kinetics of interferon (IFN) expression was determined in whole blood after in vitro stimulation with sheep pox vaccine (SPV) to determine whether a rapid method to detect cell mediated immune responses to sheep pox (SPV) vaccination against lumpy skin disease virus (LSDV) in cattle and could be used either as a diagnostic test or to provide a correlation of protection in animals post-vaccination.

Using protocols based on the BOVIGAM assay for tuberculosis, whole blood samples from (SPV) vaccinated and control cattle, before and after vaccination, were incubated with different amounts of SPV and the supernatants were harvested at different intervals and assayed for interferon-gamma (IFN-γ) by an enzyme-linked immunosorbent assay (ELISA).

24 hours culture was suitable for estimating IFN-γ release.

Specific induction of IFN was detected in samples from vaccinated cattle after different time intervals post vaccination, however INF-γ can be detected 5 days post vaccination reaching its maximum at 14 day post vaccination on contrast to the antibody detection by serum neutrization test (SNT) and ELISA which detected at 15 days post vaccination (DPV) reaching its maximum 28 days PV.

Combining the results of the IFN-γ assay with SNT antibody titre and ELISA, provided the capacity of INF-γ assay to evaluate the immune status of vaccinated cattle with SPV against LSD as further development of this assay may provide a useful tool for the determination of LSD immune status, including the identification of vaccinated and infected cattle.