The ability of antibodies against adhesion and costimulatory molecules to block the inhibitory effect of FDCs on sAg-induced autologous T-cell proliferation. Where indicated, 2 × 104 FDCs (A) or B cells (B) were incubated with 1 μg/mL of purified MoAb for 30 minutes and extensively washed before addition to cultures containing 105 autologous tonsil T cells and SEB at 100 ng/mL. Tritiated thymidine uptake was measured during the last 24 hours of a 3-day culture. Each bar represents the mean cpm + SEM of five (A) or three (B) independent experiments, and is expressed as a percentage of the response generated when T cells were cultured with only SEB. Cpm from cultures containing only T cells ranged from 535 to 1,591 in (A), and 1,004 to 3,155 in (B). Pretreatment of FDCs with antibodies against CD54 and CD106 significantly increased T-cell proliferation compared with untreated FDCs by ANOVA and Tukey’s analysis. Antibodies against CD80 and CD86 significantly reduced the ability of B cells to augment T-cell proliferation.
