Table 1: Summary of DC Phenotype and Resulting T Cell Stimulatory Capacity

DC Treatment % CD11c+, IL-12+ T Cell Stimulation (CPM ± SEM) IFN-γ Production (pg/ml ± SEM)
Untreated 4 3100 ± 245 320 ± 126
LPS matured 13 21050 ± 230 3840 ± 355
TNF-α 5 6465 ± 322 1255 ± 585
TNF-α +LPS 68 22455 ± 365 6215 ± 245

DC were untreated, matured with LPS (1µg/ml for 4h) or treated with TNF-α (500U/ml for 4h). In addition, TNFα treated DC were pulsed for a further 4h with LPS (1µg/ml). DC were stained for cell surface expression of CD11c and intracellular IL-12 and analyzed by flow cytometry. Values in the first column represent the % of CD11c+ and IL-12+ cells.Data from a representative experiment (of 2 performed) are shown. Ova primed T-cells (>90% CD3+ by flow cytometry) were stimulated for 4 days with DC treated as above. DC were loaded with ova by pulsing 1 x 106 cells with 80 μg/ml of ova for 4h. The DC:T cell ratio was 1:20 in each test. The second column represents the proliferation of cells as measured by H3-thymidine incorporation. The third column IFN γ production as measured by CelELISA. Values are mean and SEM of 3 experiments.