Suppression assay
After expansion Treg were stained with eFluor 670 Cell Proliferation Dye
and co-cultured with CFSE stained, FACS sorted, allogenic CD8+ T cells
at 1:1, 1:2, 1:4, 1:8 and 1:0 Tcell:Treg ratios in the presence of anti
CD3/CD28 beads at 1:10 cell/bead ratio. Cell culture was harvested at
day 5 and the percentage of proliferating (CFSE diluted) T cells was
calculated. The percentage of suppression was calculated as 100-[100 x
(percentage of proliferating cells with Treg present)/(percentage of
proliferating cells without Tresp present)].