Figure 2.

GZMB expression is increased upon T1-IFN priming of autoreactive CTLs. A–I: IGRP-CTL avatars were primed with IFNα, IFNβ, or IFNγ for 2 h. Cytokines were removed by washing, and then IGRP-CTL avatars were incubated for an additional 4 h in media or stimulated by coculture with βL5 cells. Representative histograms and mean fluorescence intensities (MFI) for GZMB (A–C), IFNγ (D–F), and FasL (G–I) are displayed. J–M: To determine the contribution of pathways important for CTL-mediated killing, IGRP-CTL avatars were cocultured with βL5 cells (10:1 E:T) in the presence of inhibitors known to block CTL cytotoxic function. Bars represent the percentage of βL5 cell lysis by IGRP-CTL avatars in the absence of inhibitors (J), with anti-Fas antibody (K), with CMA (L), and with pan-caspase inhibitor, Z-VAD-FMK (M). For representative histograms (A, D, and G), all lines within a panel are from a single donor. Data plotted in B, C, E, F, and H–M are mean ± SEM, where T cells from each donor (7 donors for B, C, E, F, H, and I and 5 donors for J–M) were weighted equally. There were at least three separate experiments for each donor. Statistical significance was assessed by a nonparametric paired t test with Wilcoxon post-test analysis. *P < 0.05; **P < 0.01; ***P < 0.001.