FIG. 4.

Characteristics of the primary virus-specific CD8⁺-T-cell response. The B6 mice were infected i.n. with 10⁷ EID₅₀ of the HK variants. The spleen (A to D) and BAL fluid (E) populations were sampled on day 10 at the peak of the acute response, and the early phase of memory was measured on day 30 (A to D) for the spleen. The numbers of tetramer⁺ CD8⁺ T cells were calculated from total cell counts and the percentages of cells staining. The results are expressed as means ± standard deviations, and significant differences from the HK-WT values are indicated by an asterisk (P ≤ 0.05).