Figure 4.
Direct and indirect donor T cell alloreactivity measured by IFN-γ ELISPOT at baseline, 6 months and 12 months post-randomization comparing between TAC maintained and SRL converted group. (A) IFN-γ production by PBMC incubated with PHA shows that cell viability was excellent in both groups. (B) IFN-γ production by PBMC incubated with irradiated donor cells showed no difference in direct T cell alloreactivity at 6- and 12-months. (p=0.082 for interaction group*time). (C and D) Indirect T cell alloreactivity, as measured by incubating PBMC either with a donors’ cell membrane preparation or donors’ HLA mismatched synthetic peptides, increased significantly over time in SRL group (p=0.009 and p=0.001 for interaction group*time, respectively). Results are expressed as mean ± SE for log-transformed ELISPOT counts. Analysis was performed using generalized estimating equations.