Activation of Lymphocytes Using Peptides NP To verify the predicted T cell epitopes in NP, ten synthetic peptides (Top nine of the 25 predicted peptides from NP and one unrelated peptide) were incubated with sensitized splenic lymphocytes for 5 d. Flow cytometry analysis showed that the proliferation of CD8 + T lymphocytes increased by 13.7% and 11.9% in cells stimulated with the peptides NP 89-97 and NP 198-206, respectively (Fig. 10) . Chicken IFN-c concentration in cells stimulated using peptides NP 89-97 and NP 198-206 were significantly higher than the control and unrelated peptide-stimulated cells (Fig. 11) . These results demonstrate that the peptides NP 89-97 and NP 198-206 are NP T cell epitopes in chickens of certain haplotypes.