Flow cytometry was performed on the uterine (a,c,e) and splenic (b,d,f) immune cells of ZIKV-infected (red triangles) and mock-infected (blue circles) pregnant and non-pregnant mice. Frequencies of CD4+ CD69+ (a-b), CD4+ CD25+ (c-d) CD4 T cells, and CD4+ CD25+ FoxP3+ Tregs (e-f) were measured. N=40 (3 independent experiments of 10 or 20 mice, N=8 mock non-pregnant, N=12 mock pregnant, N=8 ZIKV non-pregnant, N=12 ZIKV pregnant). Error bars represent the mean ± standard deviation.