Figure 6.

Proliferation of total lung digest cells and purified T cells to purified protein derivative (PPD). Total lung cells (Total) or co-cultures of purified T (LgT) cells and peritoneal (PMøs) or lung (LMøs) macrophages from non-vaccinated (NV, a) and BCG-vaccinated (BCG, b) guinea pigs 5 weeks following Mycobacterium tuberculosis infection were stimulated with PPD (25 μg/ml) for 4 days and the [³H]thymidine uptake was assessed. The cell populations were also treated with recombinant guinea pig interferon-γ (IFN-γ; 200 ng/ml) at the beginning of the culture period. The results represent mean ± SEM from 5–10 animals. Results are expressed as stimulation index. *P< 0·001 and ^‡P< 0·05 when compared with total cells as determined by anova.