A, B Cytokine array of human pan T cell cytokine secretion-profiles. A) TCR/CD28 activating-antibodies on anti-CD3/CD28/LAP beads induced cytokine secretion (black bars) over non-activating control beads (white bars). Loading of TGFβ1-LAP on these TCR/CD28 activating beads suppressed activation-induced secretion of cytokines in a dose-dependent manner (grey bars). B) Cytokines which were secreted by resting T cells showed little induction following TCR-activation were not affected by TGFβ1 on TCR/CD28 activating beads. The cytokine array analysis was performed once and is detailed in Additional file 2: Figure S2.