Fig. 11. (A –D ) The effect of different concentrations of thiopental on T-cell activation. CD3⁺T lymphocytes were isolated from the blood of healthy donors, incubated with thiopental in vitro  for 1 h at the concentrations indicated, and subsequently stimulated by cross-linking of the CD2 receptor using a CD2–CD2-receptor-ligand-antibody mix. Twelve hours later, the cells were assessed for CD69 expression by fluorescence-associated cell sorting analysis. Similar results were obtained in three additional independent experiments.