Figure 6.
Specific IFN-γ production to ICV’89 PPRV strain and H9 peptide in PBMCs from BoHV-4-A-PPRV-H-ΔTK-inoculated sheep detected by ELISPOT assay. PBMCs from sheep inoculated with PBS (black), control vector (BoHV-4-A-ΔTK) (blue), or BoHV-4-A-PPRV-H-ΔTK (red) were isolated at days 0 and 7 post-boost (PB), day 42 post-immunization, and day 7 post-challenge (PC) and cultured for 48 h in the presence of BEI-inactivated ICV’89 PPRV strain virus (A) or H9 peptide from PPRV-H protein (B). The production of IFN-γ was measured using an ELISPOT assay. Data are presented as average (± SEM) IFN-γ spots above background for 106 cells in each treatment group. A positive control of PBMCs activated with 1.25 μg/ml Con-A (Sigma) was always included to validate the ELISPOT assay. *p < 0.05 and **p < 0.005 Mann–Whitney test. The black arrow (D42) denotes the time of virulent PPRV ICV’89 challenge in all animals.