Figure 1. The livers of chronically infected mice contain proportionally fewer Foxp3⁺ Tregs compared to the spleen.

Bar graphs represent means with standard errors. Statistical analyses were done by Student's two-tailed t test. (A) Lymphocytes from spleens and livers of chronically infected mice were analyzed by flow cytometry for the percentage of CD4 positive cells and the percentage of that subset expressing Foxp3. The difference in percentage of CD4⁺ T cells between the spleen and the liver was statistically significant (*p< 0.05, n=8) and the difference between Foxp3⁺ CD4⁺ T cells in the spleen and liver was also statistically significant (*p< 0.00001, n=8). (B) Geometric mean fluorescent intensity (MFI) of intracellular Foxp3 staining of CD4⁺ T cells from the spleens and livers of chronically infected mice was not statistically different (p= 0.9184, n=6). (C) Overlays of representative histograms of CD69 expression on CD4⁺ Foxp3⁺ Tregs from the spleens and livers of naïve and chronically infected mice are shown. The bar graph depicts the mean percentage of Tregs that were CD69 positive (*p<0.05, n=10–16 per group, Bonferroni correction was used for multiple comparisons). (D) Foxp3⁺ CD4⁺ T cells from the spleens and livers of naïve mice and mice chronically infected with FV were analyzed for expression of CD62L, intracellular Ki-67, and CD25 (*p<0.0001, n=5–12). The differences between naïve and chronic values within the same tissue were not statistically different.