B29 induced Tregs are suppressive in vitro.

Abstract

<p>Mice were either injected with anti-CD25 antibody to deplete CD25^<b>+</b> cells, or with PBS as a control. 7 days after injection, mice (n = 3 per treatment) were immunized with either B29 (upper graph) or pOVA (lower graph). 10 days later autologous CD4^<b>+</b>CD25^<b>-</b> responder cells (white bars) and CD4^<b>+</b>CD25^<b>+</b> cells were isolated and pooled for co-culture in various ratios in the presence of anti-CD3 antibody to activate the cells. As a control, also CD4^<b>+</b>CD25^<b>-</b> responder cells from naïve (N) donors (black bars) were used to test the suppressive capacity of B29-induced Tregs or pOVA-induced Tregs on the same population of responder T cells. ^<b>3</b>H-thymidine incorporation was determined and cpm data are shown as the mean of triplicate samples (± s.e.m.). % supp. is the proliferative response of responder T cells cultures alone, compared to responder T cells co-cultured with Tregs. Data shown are representative for two independent experiments. P values are from an unpaired two-tailed Student t-test in which cpm from CD4^<b>+</b>CD25^<b>-</b> cells were compared to cpm from CD4^<b>+</b>CD25^<b>+</b> cells. ** P < 0.01, *** P < 0.001.</p