Figure 3. The immuno-adjuvant effects of the macrophage inflammatory protein (MIP) plasmids on Gag plasmid (pGag) vaccination.
Determination of (a) Gag-specific humoral responses, (b) interferon-γ (IFN-γ) expression by enzyme-linked immunosorbent spot (ELISPOT), (c) cytotoxic T lymphocyte (CTL) response, and (d) IFN-γ production by T cells in immunized BALB/c mice. Mice were intramuscularly immunized twice, at weeks 0 and 2, with 50 μg of pGag alone or in conjunction with 50 μg of one of the MIP plasmids pMIP-1α, pMIP-3α, or pMIP-3β. Animals were killed 2 weeks after the second immunization, and sera and splenocytes were harvested. Gag-specific enzyme-linked immunosorbent assay was used to measure specific immunoglobulin G (IgG), IgG1, and IgG2a levels, and the splenocytes were studied for IFN-γ production using standard ELISPOT assay. Enriched T cells of the splenocytes were used for CTL assay. T cells were cultured at 5 × 106 cells/ml in the presence of interleukin-2 (IL-2) and p7g peptide for 5 days. Culture supernatants were collected and assayed for cytokine secretion using enzyme-linked immunosorbent assay kits for mouse IFN-γ and IL-4. E:T ratio, effector-to-target-cell ratio.