Fig. 6

Combination nanovaccine enhanced antigen-specific CD4⁺ T cell responses in aged mice. Lymphocytes from DO11.10 Tg mice (0.5 × 10⁶ CD4⁺ KJ1-26⁺ cells) were adoptively transferred into young (2–6 mo) and aged (18–20 mo) BALB/c mice (n = 4) which were subsequently immunized with 100 µg of OVA adjuvanted with a combination nanovaccine (NP, Mi, and CDN) or 100 µg of OVA adjuvanted with imiquimod (ImQ). Percentage of antigen-specific CD4⁺ T cells (CD4⁺ KJ1-26⁺) or T-effector memory cells (TEM: CD4⁺ KJ1-26⁺ CD44⁺ CD62L^lo) in the draining lymph nodes were examined at 3 days post-immunization. * Indicates significant difference between treatment groups, p ≤ 0.05. Error bars represent SEM. Dashed line represents background levels of the cell percentages in lymph nodes of mice treated with saline