Figure 2. HLA-DR blockade reduces CD8⁺ T cell infiltration into and CTL development within implanted allogeneic vessel segments in vivo.

(A and B) Anti–HLA-DRα F(ab)′₂ fragment significantly (n = 6 per group) reduces total intimal T cell infiltration as detected by immunofluorescence (scale bar: 20 μm) (A) and CD8⁺ T cell–associated transcripts of cytokines and CTL effector molecules in rejected artery grafts at 21 days (B) as detected by qPCR normalized to either total mRNA or T cell–specific mRNA as indicated on the y axis. Arrows indicate infiltrating intimal CD45RO⁺ T cells. *P < 0.05, 2-tailed Student’s t test. CTL, cytotoxic T cell.