Immune responses in young and elderly mice.

<p>BALB/cBy mice of age 2 months (A, C, D, G, and H) or 20 months (B, E, F, I, and J) were immunized as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0153195#pone.0153195.g001" target="_blank">Fig 1</a>. <b>T cell responses:</b> Three weeks after the rAd immunization, T cell responses in lungs were determined by IFN-γ ELISPOT (A, B). IFN-γ responses of lung T cells are shown following stimulation with peptides NP_147–155, NP_55–69, and M2_e2–24. SARS M stimulated cells were used as controls. Bars show mean total lung IFN-γ secreting cell number per organ ± SEM for 3 or 4 mice per group. ***p≤0.05 comparison of A/NP+M2 versus B/NP by Mann-Whitney rank sum test determined for each peptide, performed only for those samples significantly above SARS M. <b>Antibody responses:</b> (C-J) Samples were collected three weeks after rAd from A/NP+M2 DNA prime-rAd boost (solid circles) and B/NP DNA prime-rAd boost (solid triangles) mice. Sera (C-F) or BAL (G-J) were analyzed by ELISA. Results show the mean of absorbance ± SEM of sera from 3–12 mice or BAL samples from 3–4 mice per group. Background from secondary antibody alone was subtracted.