Figure 1

Expansion of Treg after infection with F-MuLV. C57BL/6 mice were infected with F-MuLV and sacrificed 8 or 10 days after infection. Then, suspensions of spleen cells were prepared. Flow cytometry was used to quantify the numbers of CD8⁺ T cells specific for the H-2D^b-restricted F-MuLV glycosylated gag epitope (MHC I Tetramer⁺), and CD4⁺ T cells specific for the A^b-restricted FV-H19-Env epitope (MHC II Tetramer⁺) in the spleen. A. Numbers of CD8⁺ MHC I Tetramer⁺ T cells per one million spleen cells. B. Numbers of CD4⁺ MHC II Tetramer⁺ T cells per one million spleen cells. C. Numbers of CD4⁺ Foxp3⁺ T cells per one million spleen cells. D. Numbers of CD4⁺Foxp3⁺ T cells expressing Ki-67 per one million spleen cells. E. A representative dot plot shows the gating-strategy to identify CD4⁺ Foxp3⁺ that were Npn-1⁺ or Npn-1^-. Upper graph, numbers of CD4⁺Foxp3⁺Npn-1⁺ cells per one million nucleated cells. Lower panel, numbers of CD4⁺Foxp3⁺Npn-1^-cells per one million nucleated cells. F. A representative dot plot shows the expression of Helios and Ki67 on gated CD4⁺Foxp3⁺Npn-1⁺ nTregs (upper panel) and on gated CD4⁺Foxp3⁺Npn-1^-iTregs (lower panel). The numbers in the upper quadrants represent the percentages of Helios⁺ cells. Data was pooled from three independent experiments with similar results. Differences between naïve mice and mice infected for 10 days with F-MuLV were analyzed by an unpaired t-test. Statistically significant differences between the groups are indicated in the figure.