Figure 1.

Frequency, Function, and Gene Expression Signature of MCMV-Specific CD8⁺ T Cells

C57BL/6 mice were infected intravenously (i.v.) with 1 × 10⁶ pfus MCMV.

(A) Tetramer staining for M38- and M45-specific CD8⁺ T cells on 7 and 50 days postinfection in spleen. Mean percentages of live tetramer⁺ CD8⁺ T cells are indicated (n = 8; mean ± SEM).

(B) Time course for M38- (red) and M45- (blue) specific CD8⁺ T cells. Splenocytes from 0, 7, 21, 50, and 100 days postinfection mice were stained with tetramers and analyzed by flow cytometry. Mean percentages of live tetramer⁺ CD8⁺ lymphocytes are indicated (n = 8; mean ± SEM).

(C) Representative flow cytometry plots of splenocytes producing IFNγ or TNFα stimulated with either M38 or M45 peptide in mice 7 and 50 days postinfection, gated on live lymphocytes. Numbers indicate the percentage of IFNγ- and TNFα-positive CD8⁺ T cells (n = 8; mean ± SEM).

(D) Time course plotting the percentage of M38- (red) or M45- (blue) specific CD8⁺ T cells from the spleen producing IFNγ and TNFα after stimulation with either the M38 or M45 peptide. Mean percentage of IFNγ and TNFα producing cells within the CD8⁺ T cell compartment is indicated (n = 8; mean ± SEM).

(E) Number of genes upregulated (red) and downregulated (blue) in M38- and M45-specific CD8⁺ T cells 7 and 50 days postinfection, compared to naive CD8⁺ T cells. Filter criteria of at least 2-fold change with p ≤ 0.05 compared to naive CD8⁺ T cells are shown.

(F) Venn diagram showing the number of differentially expressed genes between M38-specific CD8⁺ T cells 7 (yellow) and 50 (red) days postinfection and M45-specific CD8⁺ T cells 7 (orange) and 50 (blue) days postinfection. Filter criteria of at least 2-fold change with p ≤ 0.05 compared to naive CD8⁺ T cells are shown. Upregulated genes are indicated in red and downregulated genes in blue.

(G) Representative flow cytometry plots of splenocytes expressing LAMP1 or producing effector molecules stimulated with either M38 or M45 peptide in mice days 7 and 50 postinfection, gated on live lymphocytes (n = 8; ±SEM). Longitudinal flow cytometry analysis shows the percentage of M38- (red) or M45- (blue) specific CD8⁺ T cells from the spleen producing effector molecules after stimulation with either the M38 or M45 peptide. Mean percentages of LAMP1-, XCL1-, CCL3-, CCL4-, CCL5-, and CCL9-positive cells within the CD8⁺ T cell compartment are indicated (n = 8; ±SEM).

See also Figure S1.