A) PBMC were untreated (medium) or stimulated with anti-CD3 (OKT3) in the presence or absence of UL11Fc (TB40), UL11Fc (Merlin), UL6Fc or the Fc control protein at the indicated concentrations for 48h. B) PBMC were untreated or stimulated with anti-CD3 or treated with 50nM UL11Fc (TB40), UL11Fc (Merlin) or Fc without anti-CD3 (UL11Fc/Fc) or with anti-CD3, following preincubation with the indicated concentrations of anti-CD45 (AICD45.2) where shown, for 96h. C) Enriched primary T cells were untreated or stimulated with anti-CD3 and anti-CD28 in the presence or absence of UL11Fc (TB40) or Fc as indicated, for 48h. IL-10 secretion into the supernatant was measured by ELISA. Single representative experiments from two or three replicates are shown. Error bars show standard deviation of technical replicates.