Figure 1.
Dimethyldioctadecylammonium/monophosphoryl lipid-A (DDA/MPL) and aluminium hydroxide [Al(OH)3] adjuvants induce antigen-specific T-helper 1 (Th1) and T-helper 2 (Th2) responses, respectively. BALB/c or C57BL/6 mice were immunized three times with Ag85B–ESAT-6 in either DDA/MPL (black bars/symbols) or Al(OH)3 (grey bars/symbols). (a) One week after the final immunization the amount of interferon-γ (IFN-γ) and interleukin-5 (IL-5) in the supernatants of pooled blood lymphocytes from six mice restimulated with antigen was determined by enzyme-linked immunosorbent assay (ELISA). Bars represent the means of triplicate determinations and error bars represent the standard error of the means. (b) Four months after the final immunization, antigen-specific IgG2a and IgG1 antibody responses in pooled serum from four mice were determined by enzyme-linked immunosorbent assay (ELISA). The cytokine levels of naïve control mice were < 0·30 pg/ml and the antibody absorbance optical density (OD) levels were < 0·1. The results are representative of at least three individual experiments.