Figure 6.

Purified aminopeptidase N (PepN) shows enhanced T cell inhibitory activity relative to Streptococcus pneumoniae (Spn) lysate and this effect is independent of toxicity. NP-specific cytotoxic T lymphocyte (CTL) were stimulated with peptide in the presence of increasing amounts of EF3030-derived lysate or purified PepN. Following stimulation, cells were stained with anti-CD8 and anti-IFNγ antibodies. 7-AAD was used to assess cell viability. (A) Mean ± SEM for PepN inhibition of IFNγ production. (B) Mean ± SEM of IFNγ mRNA following treatment of CTL with PepN. (C) Cell viability data are represented as the mean ± SEM. Data are from three independent experiments using at least two independently generated NP-specific CTL lines.