Fig. 2

Aged mice produce fewer HMPV-specific CD8 + T cells in the lung. A, B Aged infected mice had decreased CD8⁺ N11 tetramer⁺ cells in lung (shaded bars) and BAL (open bars) compared to young infected mice at day 7 post-infection. Both N11 percent of CD8⁺ tetramer⁺ T cells and absolute cell number is shown. Absolute cell number was calculated by Biolegend Precision Counting Beads. C Representative flow plots from young and aged infected lung, respectively. D-E Aged uninfected mice had fewer tetramer precursor cells in the spleen and lymph nodes compared to young uninfected mice. Tetramer precursors were enriched from uninfected mouse spleen and lymph node via magnetic column selection using APC-labeled beads. F Representative flow plots of CD8⁺ tetramer precursor cells shown. *P < 0.05, **P < 0.01, unpaired t-test