Fig. 8: Continuous expression of GFI1 is required to maintain CD8⁺ T cell persistence following chronic viral infection.

a, Representative flow cytometry plot (left) and quantification (right) of R26^Cre-ERT2/+Gfi1^fl/+ and R26^Cre-ERT2/+Gfi1^fl/fl CD8⁺ P14 T cells in peripheral blood of MCMV-ie2-gp33-infected C57BL/6 mice that received 1:1 mix of congenically labeled R26^Cre-ERT2/+Gfi1^fl/+ and R26^Cre-ERT2/+Gfi1^fl/fl CD8⁺ P14 T cells 30 days before tamoxifen treatment and were infected with MCMV-ie2-gp33 1 day post CD8⁺ T cell adoptive transfer; mean values are shown; error bars, s.e.m. b, Number of R26^Cre-ERT2/+Gfi1^fl/+ and R26^Cre-ERT2/+Gfi1^fl/fl CD8⁺ P14 T cells in spleen at D14 and D28 after tamoxifen treatment as in a; mean values are shown; error bars, s.e.m. c, Expression of TCF1, EOMES and BCL-2 in R26^Cre-ERT2/+Gfi1^fl/+ and R26^Cre-ERT2/+Gfi1^fl/fl CD8⁺ P14 T cells at D28 after tamoxifen treatment as in a. d, Representative histogram at D28 (right) and quantification at D14 and D28 (left) of Ki-67 expression in splenic R26^Cre-ERT2/+Gfi1^fl/+ and R26^Cre-ERT2/+Gfi1^fl/fl CD8⁺ P14 T cells as in a. In b–d, data are pooled from two independent experiments (n = 9 or 10 mice per time point). P values were calculated using a two-tailed paired t-test.