Figure 1From: Effectiveness of BCG vaccination to aged miceBCG vaccination to young and aged mice augments Th1 cytokine production by PPD stimulated splenocytes. Young (a, c) and aged (b, d) mice were immunized with 1 × 106 CFU of BCG or phosphate buffered saline (PBS). Eight weeks after immunization, the animals were intravenously challenged with 1 × 105 CFU of M. tuberculosis strain H37Rv. Four weeks after challenge, the levels of IL-2 (a, b) and IFN-γ (c, d) in the culture supernatants of splenocytes stimulated with PBS (open column) or PPD (solid column) were measured by ELISA (BD Biosciences). Data represent mean ± SD of three mice. *, p < 0.05, compared with PBS-stimulation (student's t-test).Back to article page