7. METHODS 7.1 Study parameters/endpoints Before the vaccination and at two different time points after vaccination with γ-irradiated BCG (2 weeks and 3 months) blood will be drawn, from which PBMCs will be isolated by density centrifugation over Ficoll-Paque. Monocytes will be restimulated ex-vivo with different pathogens (M. tuberculosis (1µg/ml), S. aureus, C. albicans (both 1 x 10^6 microorganisms/ml), and E. coli LPS (10ng/ml). Cytokine production will be assessed after 24h (TNFa, IL 1b and IL-6), 48h (IFN, IL-10) and 7 days (IL-17, IL-22) stimulation, and compared with cytokine production before vaccination.