Figure 5.

CD28-tolerized T-cells retain pathogen reactivity. Proliferation of human CD3⁺ T-cells after re-stimulation with Candida albicans or foreign third-party alloantigen. (A–C) Data points for primary mixed leukocyte reactions (MLRs) are derived from Figure 2B (+ α-huCD28) for comparison. The number of proliferated cells in primary MLRs ranged from 1 × 10² to 9 × 10³. T-cell proliferation, shown as number of proliferated cells, was analyzed by flow cytometry after a 7-day re-stimulation with (A) autologous dendritic cells with C. albicans, (B) without C. albicans as a control for possible antigen-independent proliferation, or (C) with foreign third-party alloantigen. Each point is the mean of triplicate determinations of different recipient–donor pairs used as biological replicates. **p < 0.005; ns = not significant, p > 0.05.