Figure 2.

Analysis of CD4⁺IFN-γ-secreting cells. (A) Representative experiment with PBMCs stimulated with individual porcine reproductive and respiratory syndrome virus (PRRSV) peptides, the whole virus, phytohaemagglutinin (PHA) (positive control) or medium along (unstimulated control). For extracellular labeling, an anti-CD4 antibody conjugated with fluorescein isothiocyanate (FITC) was used, and for intracellular staining, an anti-pig IFN-γ antibody conjugated with phycoerythrin (PE) was used. The selected population corresponded to CD4⁺IFN-γ⁺ cells. (B) Frequency of CD4⁺ IFN-γ-secreting cells in immunized pigs. The results were obtained by subtracting the percentage of CD4⁺IFN-γ⁺ cells in the unstimulated cell group from the percentage of double-positive cells in the experimental group.