Fig. 3

Stable engraftment is required for long-term tolerance. a–e BM (10⁷ cells) from non-Tg, MII.OVA and actin.OVA mice was transferred i.v. to B6.SJL mice under low-dose irradiation (300 cGy TBI). Rapamycin (rapa) or PBS was administered i.p. for 22 days commencing at BM transfer (BMT). Four weeks (a) or 25 weeks (b) after BMT, mice were sham (PBS/QuilA) or OVA (OVA/QuilA) immunised. Age-matched, unirradiated and untransplanted mice were immunised and analysed in parallel. One week later an in-vivo CTL assay was performed. Blood was collected at the indicated time-points and whole blood rapamycin concentration determined by HPLC (c). CD8⁺ (d) and CD4⁺ (e) T cells were enumerated in blood by flow cytometry. Data are pooled from three or four experiments and show individual mice with mean ± SEM (a, b), pooled from two experiments where mice from all experimental groups were pooled at each time-point and show individual mice with mean ± SEM (c) or pooled from three or four experiments and depict mean ± SEM (n = 8/group). ANOVA with Tukey’s post test. *PBS > rapa (p < 0.05), **PBS > rapa (p < 0.01 or greater), ***PBS > rapa (p < 0.001 or greater)