Table 1: Effects of media on fold expansion, viability and phenotype of thymic Tregs.

Cells were activated with Dynabeads Treg Xpander or CD3/CD28/CD2 T Cell Activator in ImmunoCult-XF, ImmunoCult-XF with serum replacement (SR), X-Vivo + SR or OpTmizer + SR. After 7 days the cells were restimulated with the same activators and after a total of 15 days of expansion fold expansion, viability and expression of FOXP3 was determined. All values are listed as median (range).

	Dynabeads Treg Xpander				CD3/CD28/CD2 T Cell Activator
	ImmunoCult-XF (n=8)	ImmunoCult-XF + SR (n=7)	X-Vivo + SR (n=5)	OpTmizer + SR (n=5)	ImmunoCult-XF (n=8)	ImmunoCult-XF + SR (n=7)	X-Vivo + SR (n=4)	OpTmizer + SR (n=5)
Fold expansion (day 15)	295 (40–475)	317 (7–1024)	92 (13–103)	73 (3–135)	177 (22–326)	194 (3–326)	28 (16–55)	41 (2–53)
Viability	90% (79–95%)	89% (68–91%)	92% (80–95%)	95% (79–97%)	90% (67–98%)	90% (68–96%)	89% (88–93%)	94% (94–95%)
%FOXP3+	78% (67–82%)	76% (68–89%)	85% (33–86%)	58% (43–65%)	70% (58–85%)	68% (47–72%)	78% (72–81%)	44% (34–63%)
% Suppression of proliferation (1:20 Treg to PBMC)	77% (43–95%)	89% (83–97%)	82% (46–96%)	78% (68–87%)	65% (51–92%)	58% (43–86%)	59% (45–67%)	---