Figure 5. T_reg Activation and Expansion with IL-2 and construct administration in vivo.

(a) Splenic CD4⁺Foxp3⁺ Treg expansion and activation as measured by cell counts in the spleen (top) and ICOS, CD25, GITR and KI67 expression (bottom) in A/J and C57BL/6 (b) mice. (c) In vitro suppression of C57BL/6^CD45.1+ congenic T cell proliferation by CD4⁺Foxp3⁺ T_regs isolated from splenocytes of C57BL/6^{CD45.2+Foxp3+GFP+} mice treated with saline (black), wtIL-2 (blue), mutIL-2 (green) and OMCP-mutIL-2 (red) in vivo. Data representative of four separate in vitro experiments with comparison performed by unpaired t-test to saline-treated control at each ratio indicated and confirmed by ANOVA. (d) NK/Treg ratio in the spleen of A/J or C57BL/6 (e) mice treated with saline (black), wtIL-2 (blue), mutIL-2 (green) and OMCP-mutIL-2 (red) in vivo. All graphs in a,b,d,e represent an average cell count±s.e.m. from 5 to 10 mice per group performed as 4–7 separate experiments for each strain of mice. Comparison performed by unpaired t-test between groups as indicated by the lines. ns P>0.05; *P<0.05; **P<0.01; ***P<0.001; black=saline; blue=wtIL-2, red=OMCP-mutIL-2, green=mutIL-2; turkoise wtIL-2 complexed to anti-IL-2.