Figure 6.

Effect of VCG on the proliferation of immune or naïve CD4+ T cells. Purified Chlamydia sensitized CD4⁺ immune (A) or naïve (B) T cells were cultured with BMDCs or VCG-pulsed BMDCs for 24 h and restimulated in vitro with chlamydial antigen (10⁶ IFU/ml UV-irradiated EBs) for 3 days. The antigen-specific proliferative response was determined using the BrdU incorporation assay; incorporation was detected by addition of ABTS substrate and the optical density was read at 405 nm using a scanning multi-well spectrophotometer. Results are expressed as the stimulation index (SI), the ratio between absorbance values of stimulated and non-stimulated cells and the bars represent the mean and S.D. of three independent experiments. **p < 0.001 (BMDCs versus BMDCs + EBs; BMDCs + EBs + VCG).